:root {
  --bg: #ffffff;
  --surface: #fafafd;
  --surface-strong: #f4f2fa;
  --ink: #17182b;
  --ink-2: #4d4f63;
  --ink-3: #85879a;
  --line: #e8e8f1;
  --line-strong: #dcdce8;
  --brand: #8a63cf;
  --brand-deep: #704daf;
  --pink: #ec85bd;
  --purple: #c489ef;
  --blue: #9a86f5;
  --grad: linear-gradient(115deg, #9a86f5, #c489ef 55%, #ec85bd);
  --serif: "Noto Serif JP", serif;
  --sans: "Inter", "Noto Sans JP", -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  --shell: 1080px;
  --article: 720px;
  --ease: cubic-bezier(.2, .7, .2, 1);
}

* { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; }
body {
  min-width: 320px;
  background: var(--bg);
  color: var(--ink-2);
  font-family: var(--sans);
  font-size: 16px;
  line-height: 1.8;
  letter-spacing: .01em;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}
a { color: inherit; text-decoration: none; }
img { display: block; max-width: 100%; }
button { font: inherit; }
.shell { width: 100%; max-width: var(--shell); margin: 0 auto; padding: 0 28px; }
.skip-link {
  position: fixed; left: 12px; top: -60px; z-index: 300;
  padding: 10px 16px; border: 1px solid var(--line-strong); border-radius: 9px;
  background: #fff; color: var(--ink); font-size: 13px; font-weight: 600;
  box-shadow: 0 8px 24px rgba(23, 24, 43, .12);
}
.skip-link:focus { top: 12px; }
a:focus-visible, button:focus-visible {
  outline: 2px solid var(--brand); outline-offset: 3px; border-radius: 5px;
}

/* Shared header */
.topbar { height: 3px; background: var(--grad); }
.site-header {
  position: sticky; top: 0; z-index: 100;
  border-bottom: 1px solid rgba(232, 232, 241, .9);
  background: rgba(255, 255, 255, .88);
  backdrop-filter: saturate(1.35) blur(16px);
  -webkit-backdrop-filter: saturate(1.35) blur(16px);
}
.nav-shell { min-height: 66px; display: flex; align-items: center; justify-content: space-between; gap: 24px; }
.brand { display: inline-flex; align-items: center; gap: 11px; min-width: 0; }
.brand-mark { width: 30px; height: 30px; flex: none; }
.brand-name {
  color: #414356; font-family: var(--serif); font-size: 17px;
  font-weight: 600; letter-spacing: .06em; line-height: 1.15; white-space: nowrap;
}
.brand-en {
  display: block; margin-top: 2px; color: var(--ink-3); font-family: var(--sans);
  font-size: 9px; font-weight: 500; letter-spacing: .29em; text-transform: uppercase;
}
.nav-actions { display: flex; align-items: center; gap: 24px; }
.nav-link {
  display: inline-flex; min-height: 44px; align-items: center;
  color: var(--ink-2); font-size: 13px; font-weight: 600; letter-spacing: .04em;
}
.nav-link:hover, .nav-link[aria-current="page"] { color: var(--brand-deep); }
.nav-button {
  position: relative; display: inline-flex; min-height: 42px; align-items: center; justify-content: center;
  padding: 7px 18px; border-radius: 999px; background: var(--grad); color: #fff;
  font-size: 12.5px; font-weight: 700; letter-spacing: .03em;
  box-shadow: 0 8px 20px -10px rgba(138, 99, 207, .45);
  transition: transform .2s var(--ease), box-shadow .2s var(--ease);
}
.nav-button::after { content: ""; position: absolute; inset: -2px -4px; }
.nav-button:hover { transform: translateY(-1px); box-shadow: 0 11px 24px -10px rgba(138, 99, 207, .6); }

/* Columns index */
.columns-hero { position: relative; overflow: hidden; padding: 96px 0 84px; }
.columns-hero::before {
  content: ""; position: absolute; width: 480px; height: 480px; top: -260px; right: -120px;
  border-radius: 50%; background: radial-gradient(circle, rgba(196, 137, 239, .1), transparent 68%);
  pointer-events: none;
}
.columns-hero-inner { position: relative; max-width: 760px; }
.eyebrow, .section-label {
  color: var(--brand); font-size: 11.5px; font-weight: 700; letter-spacing: .22em; text-transform: uppercase;
}
.columns-hero h1 {
  margin-top: 17px; color: var(--ink); font-family: var(--serif); font-size: clamp(34px, 6vw, 54px);
  font-weight: 700; letter-spacing: .03em; line-height: 1.38;
}
.columns-hero-lead {
  max-width: 650px; margin-top: 24px; color: var(--ink-2); font-family: var(--serif);
  font-size: clamp(15px, 2.2vw, 17px); letter-spacing: .025em; line-height: 2;
}
.featured-section { padding: 0 0 88px; }
.section-heading { display: flex; align-items: center; gap: 16px; margin-bottom: 20px; }
.section-heading::after { content: ""; height: 1px; flex: 1; background: var(--line); }
.featured-card {
  display: grid; grid-template-columns: minmax(280px, .9fr) minmax(0, 1.1fr);
  overflow: hidden; border: 1px solid var(--line); border-radius: 24px; background: #fff;
  box-shadow: 0 22px 60px -42px rgba(35, 27, 67, .42);
  transition: transform .3s var(--ease), box-shadow .3s var(--ease), border-color .3s;
}
.featured-card:hover { transform: translateY(-3px); border-color: #d8d2eb; box-shadow: 0 28px 70px -40px rgba(35, 27, 67, .5); }
.featured-visual {
  min-height: 390px; overflow: hidden; background: #f2effa;
}
.featured-visual-image { display: block; width: 100%; height: 100%; object-fit: cover; object-position: center; }
.featured-content { display: flex; flex-direction: column; justify-content: center; padding: 48px 50px; }
.article-meta { display: flex; flex-wrap: wrap; align-items: center; gap: 10px 18px; margin-bottom: 19px; }
.featured-content .article-meta-cat,
.featured-content .article-meta-date,
.featured-content .article-meta-readtime { font-size: 12.5px; font-weight: 400; }
.featured-title {
  color: var(--ink); font-family: var(--serif); font-weight: 600;
  letter-spacing: .02em; text-wrap: balance;
}
.featured-title-main { display: block; font-size: clamp(23px, 2.7vw, 30px); line-height: 1.55; }
.featured-title-sub { display: block; margin-top: 10px; color: var(--ink-2); font-size: clamp(16px, 1.8vw, 20px); font-weight: 500; line-height: 1.65; }
.featured-excerpt { margin-top: 19px; color: var(--ink-2); font-size: 14px; line-height: 1.95; }
.read-more {
  display: inline-flex; align-items: center; gap: 8px; align-self: flex-start;
  min-height: 44px; margin-top: 26px; color: var(--brand-deep); font-size: 13px; font-weight: 700;
}
.read-more span { transition: transform .2s var(--ease); }
.featured-card:hover .read-more span { transform: translateX(4px); }

.story-list-section { padding: 0 0 88px; }
.story-list { border-top: 1px solid var(--line); }
.story-list-card {
  display: grid; grid-template-columns: 250px minmax(0, 1fr) auto; align-items: center; gap: 30px;
  min-height: 190px; padding: 24px 4px; border-bottom: 1px solid var(--line);
  transition: background-color .2s ease;
}
.story-list-card:hover { background: #fbfbfd; }
.story-list-visual { overflow: hidden; aspect-ratio: 1672 / 941; border-radius: 13px; background: #f2effa; }
.story-list-visual img { width: 100%; height: 100%; object-fit: cover; transition: transform .4s var(--ease); }
.story-list-card:hover .story-list-visual img { transform: scale(1.015); }
.story-list-content .article-meta { margin-bottom: 11px; }
.story-list-content .article-meta-cat,
.story-list-content .article-meta-date,
.story-list-content .article-meta-readtime { font-size: 12px; font-weight: 400; }
.story-list-title { color: var(--ink); font-family: var(--serif); font-size: 21px; font-weight: 600; line-height: 1.55; }
.story-list-subtitle { margin-top: 4px; color: var(--ink-2); font-family: var(--serif); font-size: 15px; line-height: 1.65; }
.story-list-excerpt { margin-top: 10px; color: var(--ink-3); font-size: 12.5px; line-height: 1.75; }
.story-list-arrow { padding: 0 14px; color: var(--ink-3); font-size: 19px; transition: transform .2s ease; }
.story-list-card:hover .story-list-arrow { transform: translateX(3px); }

.topics { padding: 82px 0; border-top: 1px solid var(--line); border-bottom: 1px solid var(--line); background: var(--surface); }
.topics-head { max-width: 650px; }
.topics h2, .editorial-note h2 {
  margin-top: 14px; color: var(--ink); font-family: var(--serif); font-size: clamp(25px, 3.8vw, 34px);
  font-weight: 600; line-height: 1.5;
}
.topics-lead { margin-top: 16px; color: var(--ink-2); font-size: 14.5px; line-height: 1.95; }
.topics-grid { display: grid; grid-template-columns: repeat(4, 1fr); margin-top: 42px; border-top: 1px solid var(--line); }
.topic { padding: 26px 20px 4px 0; border-right: 1px solid var(--line); }
.topic + .topic { padding-left: 25px; }
.topic:last-child { border-right: 0; }
.topic-number { color: var(--brand); font-size: 10px; font-weight: 700; letter-spacing: .16em; }
.topic h3 { margin-top: 11px; color: var(--ink); font-family: var(--serif); font-size: 18px; font-weight: 600; }
.topic p { margin-top: 9px; color: var(--ink-3); font-size: 12.5px; line-height: 1.8; }
.editorial-note { padding: 96px 0 104px; }
.editorial-intro {
  display: grid; grid-template-columns: minmax(220px, .75fr) minmax(0, 1.25fr);
  gap: clamp(48px, 8vw, 96px); align-items: start; max-width: 920px; margin: 0 auto;
}
.editorial-heading .section-label { color: var(--ink-3); }
.editorial-copy { padding-top: 7px; }
.editorial-copy p { margin: 0; color: var(--ink-2); font-family: var(--serif); font-size: 15px; line-height: 2.05; }
.editorial-copy p + p { margin-top: 16px; }

/* Article page */
.breadcrumbs { padding-top: 25px; }
.breadcrumbs ol { display: flex; flex-wrap: wrap; gap: 7px; list-style: none; color: var(--ink-3); font-size: 11px; }
.breadcrumbs li:not(:last-child)::after { content: "/"; margin-left: 7px; color: #b8b9c6; }
.breadcrumbs a:hover { color: var(--brand); }
.article-page { padding-bottom: 24px; }
.article-header { max-width: 900px; margin: 0 auto; padding: 64px 28px 42px; text-align: left; }
.article-kicker {
  display: flex; align-items: center; gap: 11px; margin-bottom: 17px;
  color: var(--brand); font-size: 10px; font-weight: 700; letter-spacing: .2em; text-transform: uppercase;
}
.article-kicker::before { content: ""; width: 28px; height: 1px; background: var(--grad); }
.article-header .article-meta {
  flex-direction: row; align-items: center; justify-content: flex-start;
  gap: 22px; margin: 25px 0 0;
}
.article-categories, .article-facts { display: flex; align-items: center; flex-wrap: wrap; }
.article-meta-cat {
  display: inline-flex; align-items: center; color: #9279c7;
  font-size: 15.5px; font-weight: 400; letter-spacing: .045em;
}
.article-categories .article-meta-cat + .article-meta-cat::before {
  content: "/"; margin: 0 9px; color: #c8c3d7; font-weight: 400;
}
.article-meta-date, .article-meta-readtime {
  display: inline-flex; align-items: center; color: var(--ink-3);
  font-size: 15.5px; font-weight: 500; letter-spacing: .035em;
}
.article-facts > * + *::before { content: "·"; margin: 0 9px; color: #c8c3d7; }
.article-title {
  max-width: 820px; color: var(--ink); font-family: var(--serif); font-weight: 600;
  letter-spacing: .01em; text-wrap: balance;
}
.article-title-main {
  display: block; font-size: clamp(32px, 4vw, 44px); line-height: 1.4;
}
.article-title-sub {
  display: block; margin-top: 14px; color: var(--ink-2);
  font-size: clamp(19px, 2.4vw, 24px); font-weight: 500; line-height: 1.55;
}
.article-title--hybrid .article-title-main {
  color: var(--ink-2); font-family: var(--sans); font-weight: 700; letter-spacing: .02em;
}
.article-title--hybrid .article-title-sub { font-family: var(--serif); }
.article-author {
  display: grid; grid-template-columns: 116px minmax(0, 1fr);
  grid-template-areas: "portrait copy"; align-items: center;
  width: 100%; max-width: var(--article); gap: 22px; margin: 42px auto 0;
  padding: 0 28px; background: #fff; text-align: left;
}
.article-author-portrait {
  grid-area: portrait; width: 116px; height: 142px; align-self: end; overflow: hidden;
}
.article-author-portrait img { width: 100%; height: 100%; object-fit: contain; object-position: center bottom; }
.article-author-copy { grid-area: copy; }
.article-author-copy p { margin: 0; }
.article-author-label {
  color: var(--brand); font-size: 9.5px; font-weight: 700;
  letter-spacing: .1em; line-height: 1.4;
}
.article-author-name {
  margin-top: 6px !important; color: var(--ink); font-family: var(--serif);
  font-size: 17.5px; font-weight: 600; letter-spacing: .07em; line-height: 1.45;
}
.article-author-role {
  margin-top: 4px !important; color: var(--ink-3); font-size: 10.5px;
  letter-spacing: .025em; line-height: 1.55;
}
.article-author-note {
  margin-top: 9px !important; color: var(--ink-2); font-size: 11px;
  letter-spacing: .015em; line-height: 1.75;
}
.article-eyecatch {
  width: min(calc(100% - 48px), 900px); aspect-ratio: 1672 / 941;
  margin: 0 auto; overflow: hidden; border: 1px solid var(--line); border-radius: 22px;
  background: #f2effa;
  box-shadow: 0 24px 70px -48px rgba(52, 42, 95, .55);
}
.article-eyecatch img { display: block; width: 100%; height: 100%; object-fit: cover; }
.article-body {
  max-width: var(--article); margin: 0 auto; padding: 44px 28px 50px;
  color: #3c3e50; font-family: var(--sans); font-size: 16.5px;
  font-weight: 400; letter-spacing: .012em; line-height: 2;
  font-feature-settings: "palt" 1; font-kerning: normal;
}
.article-body p { margin-bottom: 26px; }
.article-body h2 {
  position: relative; margin: 68px 0 28px; padding: 0 0 17px;
  border-bottom: 1px solid var(--line); color: var(--ink); font-family: var(--serif); font-size: 24px; font-weight: 600;
  letter-spacing: .035em; line-height: 1.6;
}
.article-body h2::after {
  content: ""; position: absolute; left: 0; bottom: -1px; width: 58px; height: 2px; background: var(--grad);
}
.article-body h3 { margin: 44px 0 20px; color: var(--ink); font-family: var(--serif); font-size: 19px; font-weight: 600; line-height: 1.7; }
.article-body strong { color: var(--ink); font-weight: 700; background: linear-gradient(transparent 72%, rgba(196, 137, 239, .14) 0); }
.article-body em { color: var(--brand-deep); font-style: normal; }
.article-source-link {
  color: var(--brand-deep); text-decoration: underline; text-decoration-color: rgba(138, 99, 207, .28);
  text-decoration-thickness: 1px; text-underline-offset: .22em;
}
.article-source-link:hover { text-decoration-color: var(--brand-deep); }
.article-body blockquote {
  position: relative; margin: 46px 0; padding: 31px 32px 28px 66px; border: 0;
  border-radius: 0; background: #faf9f6; color: #3f4052;
  font-family: var(--serif); font-size: 16.5px; line-height: 2.05;
}
.article-body blockquote::before {
  content: "“"; position: absolute; top: 14px; left: 20px; color: #d6d1c9;
  font-family: Georgia, serif; font-size: 66px; font-weight: 400; line-height: 1;
}
.article-body blockquote p { margin: 0; }
.article-body blockquote cite { display: block; margin-top: 18px; color: var(--ink-3); font-family: var(--sans); font-size: 11px; font-style: normal; letter-spacing: .02em; text-align: right; }
.profile-snapshot {
  margin: 54px 0 66px; padding: 30px 0 8px;
  border-top: 1px solid var(--line-strong); border-bottom: 1px solid var(--line-strong);
}
.profile-snapshot-label, .profile-lens-label {
  margin-bottom: 8px !important; color: var(--ink-3); font-size: 10px;
  font-weight: 600; letter-spacing: .16em; text-transform: uppercase;
}
.article-body .profile-snapshot h2, .article-body .profile-lens h2 {
  margin: 0 0 23px; padding: 0; border: 0; font-size: 21px;
}
.article-body .profile-snapshot h2::after, .article-body .profile-lens h2::after { display: none; }
.profile-snapshot-list > div {
  display: grid; grid-template-columns: 112px minmax(0, 1fr); gap: 20px;
  padding: 14px 0; border-top: 1px solid var(--line);
}
.profile-snapshot-list dt { color: var(--ink-3); font-size: 12px; font-weight: 500; letter-spacing: .04em; }
.profile-snapshot-list dd { color: var(--ink); font-family: var(--serif); font-size: 14.5px; line-height: 1.8; }
.person-timeline { position: relative; margin: 42px 0 22px; list-style: none; }
.person-timeline::before {
  content: ""; position: absolute; top: 9px; bottom: 18px; left: 75px;
  width: 1px; background: var(--line-strong);
}
.person-timeline li {
  position: relative; display: grid; grid-template-columns: 58px minmax(0, 1fr);
  gap: 38px; padding: 0 0 34px;
}
.person-timeline li::before {
  content: ""; position: absolute; top: 8px; left: 71px; width: 9px; height: 9px;
  border: 2px solid #b9a4dd; border-radius: 50%; background: #fff;
}
.person-timeline time { padding-top: 1px; color: #8975b2; font-size: 12px; font-weight: 600; letter-spacing: .035em; }
.article-body .person-timeline h3 { margin: 0 0 6px; font-size: 17px; line-height: 1.65; }
.article-body .person-timeline p { margin: 0; color: var(--ink-2); font-size: 14.5px; line-height: 1.9; }
.article-source-note { margin-top: 16px; color: var(--ink-3); font-size: 11.5px; line-height: 1.85; }
.profile-lens {
  margin: 54px 0 62px; padding: 27px 0 24px;
  border-top: 1px solid var(--line-strong); border-bottom: 1px solid var(--line-strong);
}
.profile-lens ol { display: grid; grid-template-columns: repeat(4, 1fr); list-style: none; }
.profile-lens li { padding: 4px 18px 2px; border-left: 1px solid var(--line); }
.profile-lens li:first-child { padding-left: 0; border-left: 0; }
.profile-lens li:last-child { padding-right: 0; }
.profile-lens li > span { display: block; color: #a390c9; font-size: 9.5px; font-weight: 600; letter-spacing: .1em; }
.profile-lens li > strong { display: block; margin-top: 6px; background: none; font-family: var(--serif); font-size: 15px; font-weight: 600; }
.profile-lens li > p { margin: 7px 0 0; color: var(--ink-3); font-size: 11.5px; line-height: 1.75; }
.article-considerations { margin: 34px 0 40px; list-style: none; border-top: 1px solid var(--line-strong); }
.article-considerations li {
  display: grid; grid-template-columns: 116px minmax(0, 1fr); gap: 23px;
  padding: 20px 0; border-bottom: 1px solid var(--line);
}
.article-considerations strong { background: none; font-size: 13px; font-weight: 600; }
.article-considerations span { color: var(--ink-2); font-size: 14px; line-height: 1.9; }
.article-references { margin-top: 68px; padding-top: 29px; border-top: 1px solid var(--line-strong); }
.article-body .article-references h2 { margin: 0 0 22px; padding: 0; border: 0; font-size: 18px; }
.article-body .article-references h2::after { display: none; }
.article-references ol { padding-left: 19px; color: var(--ink-3); }
.article-references li { padding-left: 5px; font-size: 11.5px; line-height: 1.7; }
.article-references li + li { margin-top: 9px; }
.article-references a { text-decoration: underline; text-decoration-color: rgba(133, 135, 154, .3); text-underline-offset: .18em; }
.article-references a:hover { color: var(--brand-deep); text-decoration-color: currentColor; }

/* Relativity article diagrams */
.relativity-first-answer {
  margin: 50px 0 62px; padding: 29px 0 27px;
  border-top: 1px solid var(--line-strong); border-bottom: 1px solid var(--line-strong);
}
.relativity-figure-label {
  margin-bottom: 8px !important; color: #9a88bc; font-size: 10px;
  font-weight: 600; letter-spacing: .16em; line-height: 1.5; text-transform: uppercase;
}
.article-body .relativity-first-answer h2 {
  margin: 0 0 18px; padding: 0; border: 0; font-size: 21px;
}
.article-body .relativity-first-answer h2::after { display: none; }
.relativity-first-answer p { font-size: 15.5px; }
.concept-figure {
  margin: 46px -22px; padding: 30px 28px 25px; overflow: hidden;
  border-top: 1px solid var(--line-strong); border-bottom: 1px solid var(--line-strong);
  background: #faf9f6;
}
.concept-figure figcaption {
  margin-top: 22px; color: var(--ink-3); font-size: 11.5px;
  letter-spacing: .01em; line-height: 1.8;
}
.article-inline-visual { margin: 46px -22px 58px; }
.article-inline-visual img {
  display: block; width: 100%; height: auto; aspect-ratio: 1672 / 941;
  border-radius: 20px; object-fit: cover;
}
.article-inline-visual figcaption {
  margin: 14px 4px 0; color: var(--ink-3); font-size: 13px;
  letter-spacing: .01em; line-height: 1.8;
}
.relativity-family-grid {
  display: grid; grid-template-columns: minmax(0, 1fr) 74px minmax(0, 1fr);
  align-items: center; gap: 8px; margin-top: 22px;
}
.relativity-family-grid section { min-height: 245px; padding: 24px; background: #fff; }
.relativity-family-grid time {
  display: block; color: #9279c7; font-size: 11px; font-weight: 600; letter-spacing: .08em;
}
.article-body .relativity-family-grid h3 {
  margin: 7px 0 9px; font-size: 18px; line-height: 1.6;
}
.relativity-family-grid section > p { margin-bottom: 15px; color: var(--ink-2); font-size: 12.5px; line-height: 1.8; }
.relativity-family-grid ul { padding-left: 1.15em; color: var(--ink-3); }
.relativity-family-grid li { font-size: 11.5px; line-height: 1.8; }
.relativity-family-arrow { color: #a897c9; font-size: 22px; text-align: center; }
.relativity-family-arrow span {
  display: block; margin-bottom: 3px; color: var(--ink-3); font-size: 9px; letter-spacing: .08em;
}
.relativity-timeline { position: relative; margin: 42px 0 24px; list-style: none; }
.relativity-timeline::before {
  content: ""; position: absolute; top: 9px; bottom: 19px; left: 77px;
  width: 1px; background: var(--line-strong);
}
.relativity-timeline li {
  position: relative; display: grid; grid-template-columns: 60px minmax(0, 1fr);
  gap: 40px; padding: 0 0 34px;
}
.relativity-timeline li::before {
  content: ""; position: absolute; top: 8px; left: 73px; width: 9px; height: 9px;
  border: 2px solid #b9a4dd; border-radius: 50%; background: #fff;
}
.relativity-timeline time { color: #8975b2; font-size: 12px; font-weight: 600; letter-spacing: .035em; }
.article-body .relativity-timeline h3 { margin: 0 0 6px; font-size: 17px; }
.article-body .relativity-timeline p { margin: 0; color: var(--ink-2); font-size: 14px; line-height: 1.9; }
.relativity-aside {
  margin: 42px 0; padding: 22px 0 4px; border-top: 1px solid var(--line);
}
.relativity-aside p:last-child { font-family: var(--serif); font-size: 14.5px; line-height: 1.95; }
.relativity-aside strong { background: none; }
.light-clock-figure svg, .spacetime-figure svg { display: block; width: 100%; height: auto; margin-top: 10px; }
.diagram-heading { fill: #353647; font-family: var(--sans); font-size: 13px; font-weight: 600; }
.diagram-note { fill: #85879a; font-family: var(--sans); font-size: 11px; }
.diagram-mirror { stroke: #6f6685; stroke-width: 8; stroke-linecap: round; }
.diagram-beam { fill: none; stroke: url(#beamGradient); stroke-width: 5; stroke-linecap: round; stroke-linejoin: round; }
.diagram-light { fill: #f3b98f; filter: drop-shadow(0 0 5px rgba(243, 185, 143, .65)); }
.diagram-motion { fill: none; stroke: #aaa4b8; stroke-width: 2; }
.diagram-motion-fill { fill: #aaa4b8; }
.elevator-grid {
  display: grid; grid-template-columns: minmax(0, 1fr) 50px minmax(0, 1fr);
  align-items: center; gap: 12px; margin-top: 24px;
}
.elevator-grid section { text-align: center; }
.elevator-scene-title { margin-bottom: 14px !important; color: var(--ink); font-size: 13px; font-weight: 600; }
.elevator-grid section > p:last-child { margin: 13px 0 0; color: var(--ink-3); font-size: 11.5px; line-height: 1.7; }
.elevator-equals { color: #a897c9; font-size: 24px; text-align: center; }
.elevator-cabin {
  position: relative; width: 138px; height: 168px; margin: 0 auto;
  border: 2px solid #a9a1b8; border-radius: 70px 70px 13px 13px; background: #fff;
}
.elevator-cabin::before, .elevator-cabin::after {
  content: ""; position: absolute; left: 50%; transform: translateX(-50%);
}
.elevator-cabin::before { bottom: -10px; width: 104px; height: 3px; border-radius: 2px; background: #726881; }
.elevator-cabin.accelerating::after {
  top: -30px; width: 2px; height: 24px; background: #b49cd9;
  box-shadow: -6px 7px 0 -1px #b49cd9, 6px 7px 0 -1px #b49cd9;
}
.elevator-cabin.gravity::after {
  top: -23px; width: 12px; height: 12px; border-radius: 50%; background: #dd9daf;
  box-shadow: 0 195px 0 22px #d7d1e4;
}
.elevator-person {
  position: absolute; left: 50%; bottom: 15px; width: 22px; height: 58px;
  transform: translateX(-50%); border-radius: 13px 13px 5px 5px; background: #655d78;
}
.elevator-person::before {
  content: ""; position: absolute; top: -18px; left: 4px; width: 14px; height: 14px;
  border-radius: 50%; background: #655d78;
}
.elevator-ball {
  position: absolute; right: 25px; top: 62px; width: 11px; height: 11px;
  border-radius: 50%; background: #f3b98f; box-shadow: 0 37px 0 -3px rgba(243, 185, 143, .35);
}
.spacetime-grid-lines path { fill: none; stroke: #d5d0df; stroke-width: 1.3; }
.spacetime-orbit { fill: none; stroke: #9279c7; stroke-width: 2.5; stroke-dasharray: 7 6; }
.spacetime-planet { fill: #6a5ca0; }
.spacetime-light { fill: none; stroke: #f3b98f; stroke-width: 4; stroke-linecap: round; }
.relativity-predictions { margin: 34px 0 42px; border-top: 1px solid var(--line-strong); }
.relativity-predictions > div {
  display: grid; grid-template-columns: 126px minmax(0, 1fr); gap: 22px;
  padding: 20px 0; border-bottom: 1px solid var(--line);
}
.relativity-predictions dt { color: var(--ink); font-family: var(--serif); font-size: 14px; font-weight: 600; }
.relativity-predictions dd { color: var(--ink-2); font-size: 14px; line-height: 1.9; }
.gps-equation {
  display: grid; grid-template-columns: minmax(0, 1fr) 28px minmax(0, 1fr) 28px minmax(0, 1fr);
  align-items: center; gap: 6px; margin-top: 24px;
}
.gps-effect { min-height: 192px; padding: 23px 15px; background: #fff; text-align: center; }
.gps-effect.result { background: #f5f1fb; }
.gps-value { display: block; color: #725fa0; font-family: var(--serif); font-size: 34px; font-weight: 600; line-height: 1.2; }
.gps-unit { display: block; margin: 3px 0 13px; color: var(--ink-3); font-size: 9.5px; letter-spacing: .03em; }
.gps-effect strong { display: block; background: none; font-size: 12px; font-weight: 600; }
.gps-effect p { margin: 8px 0 0; color: var(--ink-3); font-size: 10.5px; line-height: 1.65; }
.gps-sign { color: #aaa0bb; font-size: 20px; text-align: center; }
.relativity-misconceptions strong { min-width: 0; }

/* Mercury perihelion article */
.mercury-precession-figure svg { display: block; width: 100%; height: auto; margin: 6px 0 2px; }
.mercury-orbit { fill: none; stroke-width: 3; }
.mercury-orbit-a { stroke: #88a9ad; opacity: .72; }
.mercury-orbit-b { stroke: #d4a079; opacity: .67; }
.mercury-orbit-c { stroke: #9b85bd; opacity: .64; }
.mercury-dot { fill: #514b5c; }
.mercury-advance-arrow { fill: none; stroke: #786b91; stroke-width: 2.5; stroke-linecap: round; }
.mercury-arrow-head { fill: #786b91; }
.arcsecond-scale { display: grid; gap: 25px; margin: 24px 0 14px; }
.arcsecond-scale > div {
  display: grid; grid-template-columns: minmax(0, 1fr) auto; gap: 7px 22px;
  align-items: end; color: var(--ink-2); font-size: 12px;
}
.arcsecond-scale strong { color: var(--ink); font-size: 12px; font-weight: 600; }
.arcsecond-scale i { grid-column: 1 / -1; display: block; height: 8px; border-radius: 99px; }
.moon-scale i { width: 100%; background: #d8e1e1; }
.mercury-scale i { width: max(2.4%, 13px); background: #d6a078; box-shadow: 0 0 0 5px rgba(214, 160, 120, .1); }
.mercury-ledger {
  display: grid; grid-template-columns: minmax(0, 1fr) 30px minmax(0, 1fr) 30px minmax(0, 1fr);
  align-items: stretch; gap: 5px; margin: 24px 0 14px;
}
.mercury-ledger > div { display: flex; min-height: 142px; flex-direction: column; justify-content: space-between; padding: 22px 19px; background: #fff; }
.mercury-ledger > div span { color: var(--ink-3); font-size: 11px; line-height: 1.75; }
.mercury-ledger > div strong { color: var(--ink); font-family: var(--serif); font-size: 15px; line-height: 1.6; }
.mercury-ledger > .ledger-residual { background: #faf1e9; }
.mercury-ledger > .ledger-residual strong { color: #9b664c; }
.ledger-symbol { align-self: center; color: #aaa1b5; font-size: 22px; text-align: center; }
.gravity-comparison-grid { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 12px; margin-top: 23px; }
.gravity-comparison-grid section { padding: 25px 24px 23px; background: #fff; }
.article-body .gravity-comparison-grid h3 { margin: 4px 0 19px; font-family: var(--serif); font-size: 18px; }
.gravity-comparison-grid .comparison-year { margin: 0; color: var(--ink-3); font-family: var(--sans); font-size: 10px; letter-spacing: .14em; }
.gravity-comparison-grid section > p:last-child { margin: 18px 0 0; color: var(--ink-2); font-size: 11.5px; line-height: 1.85; }
.comparison-orbit { position: relative; width: min(100%, 230px); height: 126px; margin: 0 auto; overflow: hidden; }
.comparison-orbit::before,
.comparison-orbit::after {
  content: ""; position: absolute; left: 50%; top: 50%; width: 184px; height: 82px;
  border: 1.8px solid #9caeb0; border-radius: 50%; transform: translate(-50%, -50%);
}
.newton-orbit::after { display: none; }
.einstein-orbit::before { border-color: #a58cc0; transform: translate(-50%, -50%) rotate(-5deg); }
.einstein-orbit::after { border-color: rgba(216, 157, 113, .62); transform: translate(-50%, -50%) rotate(8deg); }
.comparison-sun { position: absolute; z-index: 3; left: 39%; top: 50%; width: 34px; height: 34px; border-radius: 50%; background: #dfa06d; transform: translate(-50%, -50%); box-shadow: 0 0 0 7px rgba(223, 160, 109, .12); }
.comparison-planet { position: absolute; z-index: 4; right: 19px; top: 40px; width: 9px; height: 9px; border-radius: 50%; background: #504b59; }
.comparison-grid-warp {
  position: absolute; inset: 3px 7px; border-radius: 50%; opacity: .55;
  background: repeating-radial-gradient(ellipse at 39% 50%, transparent 0 17px, rgba(143, 123, 173, .23) 18px 19px);
}
.article-callout {
  margin: 48px 0 54px; padding: 6px 34px 4px; border: 0; border-radius: 0;
  background: transparent;
}
.article-callout-title { margin-bottom: 18px; color: var(--brand); font-family: var(--sans); font-size: 10.5px; font-weight: 700; letter-spacing: .22em; text-transform: uppercase; }
.article-callout-title::after {
  content: ""; display: block; width: 32px; height: 1px; margin-top: 10px; background: #c8b6df;
}
.article-callout p { margin-bottom: 16px; font-size: 15.5px; line-height: 1.95; }
.article-callout p:last-child { margin-bottom: 0; }
.article-divider { position: relative; width: 120px; height: 1px; margin: 64px auto; background: var(--grad); opacity: .55; }
.article-divider::after { content: "✦"; position: absolute; left: 50%; top: 50%; transform: translate(-50%, -53%); padding: 0 12px; background: #fff; color: var(--brand); font-family: var(--sans); font-size: 11px; }
.article-signature { max-width: 760px; margin: 0 auto 42px; padding: 0 28px; text-align: right; }
.article-signature-name { margin-bottom: 3px !important; color: var(--ink); font-size: 14px; font-weight: 600; letter-spacing: .08em; }
.article-signature-role { margin-bottom: 0 !important; color: var(--ink-3); font-family: var(--sans); font-size: 10.5px; letter-spacing: .08em; }
.article-related-reading { max-width: 760px; margin: 0 auto 48px; padding: 0 28px; }
.article-related-reading-title {
  margin-bottom: 16px; color: var(--ink); font-family: var(--serif);
  font-size: 18px; font-weight: 600; letter-spacing: .04em;
}
.article-related-reading-list { display: grid; gap: 12px; }
.article-related-reading-link {
  display: grid; grid-template-columns: minmax(0, 1fr) auto; align-items: center; gap: 24px;
  padding: 25px 27px; background: #faf9f6; color: inherit;
  transition: background-color .2s ease, transform .2s ease;
}
.article-related-reading-link:hover { background: #f6f4ef; transform: translateY(-1px); }
.article-related-reading-copy { display: block; min-width: 0; }
.article-related-reading-kind { display: block; margin-bottom: 7px; color: var(--ink-3); font-size: 10.5px; letter-spacing: .06em; }
.article-related-reading-name { display: block; color: var(--ink); font-family: var(--serif); font-size: 18px; font-weight: 600; line-height: 1.55; }
.article-related-reading-excerpt { display: block; margin-top: 7px; color: var(--ink-2); font-size: 12.5px; line-height: 1.75; }
.article-related-reading-arrow { color: var(--ink-3); font-family: var(--sans); font-size: 18px; transition: transform .2s ease; }
.article-related-reading-link:hover .article-related-reading-arrow { transform: translateX(3px); }
.article-cta {
  max-width: 800px; margin: 0 auto 36px; padding: 52px 40px; border: 1px solid var(--line);
  border-radius: 22px; background: linear-gradient(125deg, #fbf8ff, #f1f3ff); text-align: center;
}
.article-cta-eyebrow { color: var(--brand); font-size: 10.5px; font-weight: 700; letter-spacing: .24em; text-transform: uppercase; }
.article-cta-title { margin-top: 14px; color: var(--ink); font-family: var(--serif); font-size: 24px; font-weight: 600; line-height: 1.65; }
.article-cta-lead { max-width: 600px; margin: 17px auto 25px; color: var(--ink-2); font-family: var(--serif); font-size: 14px; line-height: 1.95; }
.article-cta-btn {
  display: inline-flex; min-height: 48px; align-items: center; justify-content: center;
  padding: 12px 25px; border-radius: 999px; background: var(--grad); color: #fff;
  font-size: 13px; font-weight: 700; box-shadow: 0 12px 26px -13px rgba(138, 99, 207, .5);
}
.article-back-link {
  display: flex; min-height: 48px; align-items: center; justify-content: center; gap: 8px;
  width: fit-content; margin: 0 auto 82px; color: var(--brand-deep); font-size: 13px; font-weight: 700;
}
.article-back-link::before { content: "←"; }

/* Kant: Critique of Pure Reason */
.kant-entry {
  margin: 54px 0 66px; padding: 29px 0 28px;
  border-top: 1px solid var(--line-strong); border-bottom: 1px solid var(--line-strong);
}
.article-body .kant-entry h2 {
  margin: 0 0 16px; padding: 0; border: 0; font-size: 21px;
}
.article-body .kant-entry h2::after { display: none; }
.kant-entry p:last-child {
  margin: 0; color: var(--ink); font-family: var(--serif); font-size: 19px; line-height: 1.9;
}
.kant-two-layers { margin: 34px 0 42px; border-top: 1px solid var(--line-strong); }
.kant-two-layers > div {
  display: grid; grid-template-columns: 152px minmax(0, 1fr); gap: 25px;
  padding: 21px 0; border-bottom: 1px solid var(--line);
}
.kant-two-layers dt { color: var(--ink); font-family: var(--serif); font-size: 16px; font-weight: 600; }
.kant-two-layers dd { color: var(--ink-2); font-size: 16px; line-height: 1.85; }
.kant-cognition-flow {
  display: grid; grid-template-columns: minmax(0, 1fr) 34px minmax(0, 1fr) 34px minmax(0, 1fr);
  align-items: center; gap: 7px; margin-top: 5px;
}
.kant-cognition-stage {
  min-height: 146px; display: flex; flex-direction: column; justify-content: center;
  padding: 21px 17px; background: #fff; text-align: center;
}
.kant-cognition-center { background: #f5f1fb; }
.kant-cognition-stage span { color: var(--ink-3); font-size: 13px; line-height: 1.6; }
.kant-cognition-stage strong {
  display: block; margin-top: 9px; background: none; font-family: var(--serif); font-size: 16px; line-height: 1.65;
}
.kant-cognition-arrow { color: #a795c8; font-size: 22px; text-align: center; }
.kant-terms strong { white-space: nowrap; }
.kant-big-questions {
  margin: 34px 0 42px; padding: 0; list-style: none; border-top: 1px solid var(--line-strong);
}
.kant-big-questions li {
  position: relative; padding: 17px 10px 17px 31px; border-bottom: 1px solid var(--line);
  color: var(--ink); font-family: var(--serif); font-size: 17px; line-height: 1.75;
}
.kant-big-questions li::before {
  content: ""; position: absolute; left: 7px; top: 29px; width: 6px; height: 6px;
  border: 1px solid #a994cc; border-radius: 50%;
}
.kant-reflection {
  position: relative; margin: 38px 0 48px; padding: 0; list-style: none;
}
.kant-reflection::before {
  content: ""; position: absolute; left: 20px; top: 15px; bottom: 22px;
  width: 1px; background: var(--line-strong);
}
.kant-reflection li {
  position: relative; display: grid; grid-template-columns: 42px minmax(0, 1fr); gap: 22px;
  padding: 0 0 30px;
}
.kant-reflection li > span {
  position: relative; z-index: 1; display: flex; width: 42px; height: 42px;
  align-items: center; justify-content: center; border: 1px solid #c7b6df; border-radius: 50%;
  background: #fff; color: #8c75b8; font-size: 11px; font-weight: 600;
}
.kant-reflection strong { display: block; background: none; font-family: var(--serif); font-size: 18px; line-height: 1.65; }
.kant-reflection p { margin: 7px 0 0; color: var(--ink-2); font-size: 16px; line-height: 1.85; }
.kant-series { margin: 38px 0 44px; border-top: 1px solid var(--line-strong); }
.kant-series-item {
  display: grid; grid-template-columns: 96px 190px minmax(0, 1fr); gap: 22px; align-items: baseline;
  padding: 22px 0; border-bottom: 1px solid var(--line);
}
.kant-series-item > span { color: var(--ink-3); font-size: 11px; font-weight: 600; letter-spacing: .1em; }
.article-body .kant-series-item h3 { margin: 0; font-size: 18px; }
.kant-series-item p { margin: 0; color: var(--ink-2); font-size: 15px; line-height: 1.8; }
.kant-series-item.current > span { color: var(--brand-deep); }
.kant-series a.kant-series-item { color: inherit; transition: color .2s ease; }
.kant-series a.kant-series-item:hover h3 { color: var(--brand-deep); }

/* Kant: Critique of Practical Reason */
.practical-reason-pair {
  display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 26px;
  margin: 36px 0 44px; border-top: 1px solid var(--line-strong); border-bottom: 1px solid var(--line-strong);
}
.practical-reason-pair section { padding: 26px 4px 25px; }
.practical-reason-pair section + section { padding-left: 28px; border-left: 1px solid var(--line); }
.practical-reason-pair span,
.practical-imperative-label {
  color: #9a88bc; font-size: 11px; font-weight: 600; letter-spacing: .13em;
}
.article-body .practical-reason-pair h3,
.article-body .practical-imperatives h3 {
  margin: 8px 0 10px; font-size: 19px; line-height: 1.55;
}
.practical-reason-pair p,
.practical-imperatives section > p:last-child {
  margin: 0; color: var(--ink-2); font-size: 16px; line-height: 1.85;
}
.practical-work-line {
  display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); margin: 42px 0 52px;
  border-top: 1px solid var(--line-strong); border-bottom: 1px solid var(--line-strong);
}
.practical-work-line > div { min-width: 0; padding: 24px 22px 25px; }
.practical-work-line > div + div { border-left: 1px solid var(--line); }
.practical-work-line time { display: block; color: #9279c7; font-size: 13px; font-weight: 600; }
.practical-work-line strong {
  display: block; margin-top: 7px; background: none; font-family: var(--serif); font-size: 15px; line-height: 1.65;
}
.practical-work-line span { display: block; margin-top: 7px; color: var(--ink-3); font-size: 13px; line-height: 1.75; }
.practical-imperatives {
  display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 0;
  margin: 36px 0 44px; border-top: 1px solid var(--line-strong); border-bottom: 1px solid var(--line-strong);
}
.practical-imperatives section { padding: 26px 26px 28px 4px; }
.practical-imperatives section + section { padding-left: 28px; padding-right: 4px; border-left: 1px solid var(--line); }
.practical-imperative-label { margin: 0 !important; }
.practical-criticisms strong { white-space: normal; }

/* Kant: Critique of Judgment */
.judgment-two-worlds {
  display: grid; grid-template-columns: minmax(0, 1fr) 48px minmax(0, 1fr);
  align-items: center; margin: 36px 0 46px;
  border-top: 1px solid var(--line-strong); border-bottom: 1px solid var(--line-strong);
}
.judgment-two-worlds section { padding: 27px 5px 28px; }
.judgment-two-worlds section:last-child { text-align: right; }
.judgment-two-worlds section > span,
.judgment-kind-label,
.judgment-purpose-pair section > span {
  color: #9a88bc; font-size: 11px; font-weight: 600; letter-spacing: .13em;
}
.article-body .judgment-two-worlds h3,
.article-body .judgment-kinds h3,
.article-body .judgment-purpose-pair h3,
.article-body .judgment-sublime-pair h3 {
  margin: 8px 0 9px; font-size: 19px; line-height: 1.55;
}
.judgment-two-worlds p,
.judgment-kinds section > p:last-child,
.judgment-purpose-pair p,
.judgment-sublime-pair section > p:last-child {
  margin: 0; color: var(--ink-2); font-size: 16px; line-height: 1.85;
}
.judgment-bridge-mark { color: #a994cc; font-size: 22px; text-align: center; }
.judgment-kinds,
.judgment-purpose-pair,
.judgment-sublime-pair {
  display: grid; grid-template-columns: repeat(2, minmax(0, 1fr));
  margin: 36px 0 46px; border-top: 1px solid var(--line-strong); border-bottom: 1px solid var(--line-strong);
}
.judgment-kinds section,
.judgment-purpose-pair section,
.judgment-sublime-pair section { padding: 27px 26px 28px 4px; }
.judgment-kinds section + section,
.judgment-purpose-pair section + section,
.judgment-sublime-pair section + section {
  padding-right: 4px; padding-left: 28px; border-left: 1px solid var(--line);
}
.judgment-kind-label { margin: 0 !important; }
.judgment-criticisms strong { white-space: normal; }

@media (max-width: 760px) {
  .practical-reason-pair,
  .practical-imperatives { grid-template-columns: 1fr; gap: 0; }
  .practical-reason-pair section,
  .practical-reason-pair section + section,
  .practical-imperatives section,
  .practical-imperatives section + section { padding: 22px 0; border: 0; }
  .practical-reason-pair section + section,
  .practical-imperatives section + section { border-top: 1px solid var(--line); }
  .article-body .practical-reason-pair h3,
  .article-body .practical-imperatives h3 { font-size: 19px; }
  .practical-reason-pair p,
  .practical-imperatives section > p:last-child { font-size: 16px; }
  .practical-work-line { grid-template-columns: 1fr; }
  .practical-work-line > div,
  .practical-work-line > div + div { padding: 20px 0; border: 0; }
  .practical-work-line > div + div { border-top: 1px solid var(--line); }
  .practical-work-line strong { font-size: 16px; }
  .practical-work-line span { font-size: 14px; }

  .judgment-two-worlds { grid-template-columns: 1fr; }
  .judgment-two-worlds section,
  .judgment-two-worlds section:last-child { padding: 22px 0; text-align: left; }
  .judgment-two-worlds section:last-child { border-top: 1px solid var(--line); }
  .judgment-bridge-mark {
    width: 34px; height: 34px; margin: -17px auto; border: 1px solid var(--line-strong);
    border-radius: 50%; background: #fff; font-size: 0; line-height: 34px; position: relative; z-index: 1;
  }
  .judgment-bridge-mark::after { content: "\2195"; font-size: 18px; }
  .judgment-kinds,
  .judgment-purpose-pair,
  .judgment-sublime-pair { grid-template-columns: 1fr; }
  .judgment-kinds section,
  .judgment-kinds section + section,
  .judgment-purpose-pair section,
  .judgment-purpose-pair section + section,
  .judgment-sublime-pair section,
  .judgment-sublime-pair section + section { padding: 22px 0; border: 0; }
  .judgment-kinds section + section,
  .judgment-purpose-pair section + section,
  .judgment-sublime-pair section + section { border-top: 1px solid var(--line); }
  .article-body .judgment-two-worlds h3,
  .article-body .judgment-kinds h3,
  .article-body .judgment-purpose-pair h3,
  .article-body .judgment-sublime-pair h3 { font-size: 19px; }
}

@media (max-width: 760px) {
  .kant-entry { margin: 44px 0 52px; padding: 25px 0 24px; }
  .article-body .kant-entry h2 { font-size: 19px; }
  .kant-entry p:last-child { font-size: 18px; }
  .kant-two-layers > div { grid-template-columns: 1fr; gap: 7px; padding: 19px 0; }
  .kant-two-layers dt { font-size: 17px; }
  .kant-two-layers dd { font-size: 16px; }
  .kant-cognition-flow { grid-template-columns: 1fr; gap: 0; }
  .kant-cognition-stage { min-height: 0; padding: 22px 16px; }
  .kant-cognition-stage span { font-size: 13px; }
  .kant-cognition-stage strong { font-size: 17px; }
  .kant-cognition-arrow { padding: 7px 0; transform: rotate(90deg); }
  .kant-big-questions li { padding-left: 29px; font-size: 17px; }
  .kant-reflection li { gap: 17px; }
  .kant-reflection strong { font-size: 17px; }
  .kant-reflection p { font-size: 16px; }
  .kant-series-item { grid-template-columns: 1fr; gap: 5px; padding: 21px 0; }
  .article-body .kant-series-item h3 { font-size: 18px; }
  .kant-series-item p { font-size: 16px; }
}

/* Shared footer */
.site-footer { padding: 56px 0 38px; border-top: 1px solid var(--line); background: var(--surface); }
.footer-top { display: flex; flex-wrap: wrap; justify-content: space-between; gap: 38px; margin-bottom: 36px; }
.footer-brand-copy { margin-top: 13px; max-width: 330px; color: var(--ink-3); font-size: 12.5px; line-height: 1.85; }
.footer-links { display: flex; flex-wrap: wrap; gap: 46px; }
.footer-group h2 { margin-bottom: 12px; color: var(--ink-3); font-size: 10.5px; font-weight: 700; letter-spacing: .14em; text-transform: uppercase; }
.footer-group a { display: block; min-height: 34px; color: var(--ink-2); font-size: 13px; }
.footer-group a:hover { color: var(--brand); }
.footer-bottom { display: flex; flex-wrap: wrap; align-items: center; justify-content: space-between; gap: 12px 20px; padding-top: 21px; border-top: 1px solid var(--line); }
.footer-copy, .footer-legal a { color: var(--ink-3); font-size: 11.5px; }
.footer-legal { display: flex; flex-wrap: wrap; gap: 10px 16px; }
.footer-legal a:hover { color: var(--brand); }
.sp-only { display: none; }

@media (max-width: 760px) {
  .shell { padding: 0 20px; }
  .nav-shell { min-height: 62px; gap: 12px; }
  .brand-mark { width: 28px; height: 28px; }
  .brand-name { font-size: 15px; }
  .brand-en { font-size: 8px; letter-spacing: .24em; }
  .nav-actions { gap: 11px; }
  .nav-link { font-size: 12px; }
  .nav-button { min-height: 40px; padding: 8px 14px; font-size: 11.5px; }
  .columns-hero { padding: 62px 0 54px; }
  .columns-hero h1 { margin-top: 13px; font-size: 35px; line-height: 1.4; }
  .columns-hero-lead { margin-top: 18px; font-size: 15px; line-height: 1.9; }
  .featured-section { padding-bottom: 64px; }
  .featured-card { grid-template-columns: 1fr; border-radius: 19px; }
  .featured-visual { min-height: 0; aspect-ratio: 1672 / 941; }
  .featured-content { padding: 27px 23px 29px; }
  .featured-content .article-meta-cat,
  .featured-content .article-meta-date,
  .featured-content .article-meta-readtime { font-size: 12px; }
  .featured-title-main { font-size: 21px; line-height: 1.6; }
  .featured-title-sub { margin-top: 7px; font-size: 16px; line-height: 1.65; }
  .featured-excerpt { font-size: 14px; line-height: 1.9; }
  .read-more { margin-top: 18px; }
  .story-list-section { padding-bottom: 64px; }
  .story-list-card { grid-template-columns: 112px minmax(0, 1fr); gap: 17px; min-height: 0; padding: 19px 0; }
  .story-list-content .article-meta { margin-bottom: 8px; }
  .story-list-content .article-meta-cat,
  .story-list-content .article-meta-date,
  .story-list-content .article-meta-readtime { font-size: 10.5px; }
  .story-list-title { font-size: 16.5px; line-height: 1.55; }
  .story-list-subtitle { margin-top: 2px; font-size: 12.5px; line-height: 1.55; }
  .story-list-excerpt, .story-list-arrow { display: none; }
  .topics { padding: 62px 0; }
  .topics-grid { grid-template-columns: repeat(2, 1fr); margin-top: 32px; }
  .topic { padding: 22px 18px 22px 0; border-bottom: 1px solid var(--line); }
  .topic + .topic { padding-left: 18px; }
  .topic:nth-child(2) { border-right: 0; }
  .topic:nth-child(3), .topic:nth-child(4) { border-bottom: 0; }
  .topic:nth-child(3) { padding-left: 0; }
  .editorial-note { padding: 64px 0; }
  .editorial-intro { grid-template-columns: 1fr; gap: 25px; }
  .editorial-copy { padding-top: 0; }
  .editorial-copy p { font-size: 14.5px; line-height: 2; }
  .breadcrumbs { padding-top: 18px; }
  .article-header { padding: 42px 20px 31px; }
  .article-kicker { margin-bottom: 14px; font-size: 9px; }
  .article-header .article-meta { gap: 10px 18px; margin-top: 19px; }
  .article-title-main { font-size: clamp(27px, 7.8vw, 32px); line-height: 1.45; }
  .article-title-sub { margin-top: 10px; font-size: clamp(17px, 5.1vw, 20px); line-height: 1.55; }
  .article-meta-cat { font-size: 14.5px; }
  .article-meta-date, .article-meta-readtime { font-size: 14.5px; }
  .article-author {
    grid-template-columns: 88px minmax(0, 1fr); gap: 16px; margin-top: 36px;
    padding: 0 20px;
  }
  .article-author-portrait { width: 88px; height: 108px; }
  .article-author-name { font-size: 16px; }
  .article-author-role { font-size: 9.5px; }
  .article-author-note { margin-top: 7px !important; font-size: 10.3px; line-height: 1.68; }
  .article-eyecatch { width: calc(100% - 34px); border-radius: 17px; }
  .article-body { padding: 34px 20px 42px; font-size: 16px; line-height: 1.95; }
  .article-body p { margin-bottom: 24px; }
  .article-body h2 { margin: 54px 0 23px; padding-bottom: 14px; font-size: 21px; line-height: 1.62; }
  .article-body blockquote { margin: 38px -4px; padding: 26px 20px 23px 49px; font-size: 15.5px; }
  .article-body blockquote::before { top: 13px; left: 14px; font-size: 52px; }
  .profile-snapshot { margin: 44px 0 52px; padding-top: 25px; }
  .article-body .profile-snapshot h2, .article-body .profile-lens h2 { font-size: 19px; }
  .profile-snapshot-list > div { grid-template-columns: 82px minmax(0, 1fr); gap: 15px; padding: 12px 0; }
  .profile-snapshot-list dt { font-size: 11px; }
  .profile-snapshot-list dd { font-size: 13.5px; }
  .person-timeline { margin-top: 34px; }
  .person-timeline::before { left: 55px; }
  .person-timeline li { grid-template-columns: 40px minmax(0, 1fr); gap: 30px; padding-bottom: 29px; }
  .person-timeline li::before { left: 51px; }
  .person-timeline time { font-size: 10.5px; }
  .article-body .person-timeline h3 { font-size: 15.5px; }
  .article-body .person-timeline p { font-size: 13.5px; line-height: 1.85; }
  .profile-lens { margin: 44px 0 50px; padding: 24px 0 20px; }
  .profile-lens ol { grid-template-columns: repeat(2, 1fr); }
  .profile-lens li { padding: 10px 15px 16px; }
  .profile-lens li:first-child { padding-left: 0; }
  .profile-lens li:nth-child(3) { padding-left: 0; border-left: 0; border-top: 1px solid var(--line); }
  .profile-lens li:nth-child(4) { border-top: 1px solid var(--line); }
  .profile-lens li > p { font-size: 11px; }
  .article-considerations li { grid-template-columns: 1fr; gap: 6px; padding: 17px 0; }
  .article-considerations span { font-size: 13.5px; line-height: 1.85; }
  .article-references { margin-top: 55px; }
  .relativity-first-answer { margin: 42px 0 50px; padding: 25px 0 22px; }
  .article-body .relativity-first-answer h2 { font-size: 19px; }
  .relativity-first-answer p { font-size: 15px; }
  .concept-figure { margin: 38px -2px; padding: 24px 17px 21px; }
  .concept-figure figcaption { font-size: 10.8px; }
  .article-inline-visual { margin: 34px -2px 46px; }
  .article-inline-visual img { border-radius: 14px; }
  .article-inline-visual figcaption { margin: 12px 2px 0; font-size: 13px; line-height: 1.75; }
  .relativity-family-grid { grid-template-columns: 1fr; gap: 10px; }
  .relativity-family-grid section { min-height: 0; padding: 20px; }
  .relativity-family-arrow { transform: rotate(90deg); font-size: 19px; }
  .relativity-family-arrow span { display: none; }
  .relativity-timeline::before { left: 56px; }
  .relativity-timeline li { grid-template-columns: 41px minmax(0, 1fr); gap: 31px; padding-bottom: 29px; }
  .relativity-timeline li::before { left: 52px; }
  .relativity-timeline time { font-size: 10.5px; }
  .article-body .relativity-timeline h3 { font-size: 15.5px; }
  .article-body .relativity-timeline p { font-size: 13.5px; line-height: 1.85; }
  .light-clock-figure svg, .spacetime-figure svg { min-width: 0; }
  .diagram-heading { font-size: 14px; }
  .diagram-note { font-size: 12px; }
  .elevator-grid { grid-template-columns: 1fr 24px 1fr; gap: 5px; }
  .elevator-cabin { width: 112px; height: 145px; }
  .elevator-grid section > p:last-child { font-size: 10px; }
  .elevator-person { height: 49px; }
  .elevator-cabin.gravity::after { box-shadow: 0 170px 0 18px #d7d1e4; }
  .relativity-predictions > div { grid-template-columns: 1fr; gap: 6px; padding: 17px 0; }
  .relativity-predictions dd { font-size: 13.5px; line-height: 1.85; }
  .gps-equation { grid-template-columns: 1fr; gap: 7px; }
  .gps-effect { display: grid; grid-template-columns: 82px minmax(0, 1fr); grid-template-rows: auto auto; min-height: 0; padding: 17px 15px; text-align: left; }
  .gps-value { grid-row: 1 / 3; align-self: center; font-size: 29px; text-align: center; }
  .gps-unit { grid-column: 1; grid-row: 3; margin: 0; text-align: center; }
  .gps-effect strong { grid-column: 2; align-self: end; }
  .gps-effect p { grid-column: 2; margin-top: 4px; }
  .gps-sign { transform: rotate(90deg); line-height: 1; }
  .mercury-precession-figure svg { margin-top: 1px; }
  .arcsecond-scale { gap: 22px; margin-top: 20px; }
  .arcsecond-scale > div { grid-template-columns: 1fr; gap: 3px; }
  .arcsecond-scale strong { font-size: 11.5px; }
  .arcsecond-scale i { grid-column: 1; margin-top: 5px; }
  .mercury-ledger { grid-template-columns: 1fr; gap: 7px; }
  .mercury-ledger > div { min-height: 0; padding: 18px 17px; }
  .mercury-ledger > div strong { margin-top: 6px; }
  .ledger-symbol { transform: rotate(90deg); font-size: 18px; line-height: 1; }
  .gravity-comparison-grid { grid-template-columns: 1fr; gap: 10px; }
  .gravity-comparison-grid section { padding: 22px 20px; }
  .comparison-orbit { height: 116px; }
  .article-signature { margin-bottom: 34px; padding: 0 20px; }
  .article-related-reading { margin-bottom: 36px; padding: 0 20px; }
  .article-related-reading-title { margin-bottom: 13px; font-size: 17px; }
  .article-related-reading-link { gap: 15px; padding: 21px 20px; }
  .article-related-reading-kind { font-size: 10px; }
  .article-related-reading-name { font-size: 16.5px; }
  .article-related-reading-excerpt { font-size: 11.5px; }
  .article-callout { margin: 40px 0 48px; padding: 3px 12px 2px; border-radius: 0; }
  .article-callout p { font-size: 15px; }
  .article-divider { margin: 52px auto; }
  .article-cta { margin: 0 20px 28px; padding: 36px 22px; border-radius: 18px; }
  .article-cta-title { font-size: 21px; }
  .article-cta-lead { font-size: 13.5px; }
  .article-cta-btn { width: 100%; }
  .article-back-link { margin-bottom: 60px; }
  .site-footer { padding: 46px 0 30px; }
  .footer-top { flex-direction: column; gap: 28px; }
  .footer-links { width: 100%; gap: 26px; }
  .footer-group { min-width: 125px; }
}

@media (max-width: 390px) {
  .shell { padding: 0 17px; }
  .nav-link { display: none; }
  .columns-hero h1 { font-size: 32px; }
  .featured-content { padding-left: 20px; padding-right: 20px; }
  .article-author { padding-left: 18px; padding-right: 18px; }
  .article-body { padding-left: 18px; padding-right: 18px; }
  .footer-links { gap: 22px; }
}

/* Readability type scale
   Body 18px / supporting copy 16px / metadata 14px.
   Decorative labels remain smaller, but meaningful text does not. */
.nav-link { font-size: 14px; }
.nav-button { min-height: 42px; font-size: 15px; }
.eyebrow, .section-label { font-size: 12px; }
.columns-hero-lead { font-size: 18px; line-height: 1.9; }
.featured-content .article-meta-cat,
.featured-content .article-meta-date,
.featured-content .article-meta-readtime { font-size: 14px; }
.featured-excerpt { font-size: 16px; line-height: 1.85; }
.read-more { font-size: 16px; }
.story-list-content .article-meta-cat,
.story-list-content .article-meta-date,
.story-list-content .article-meta-readtime { font-size: 14px; }
.story-list-subtitle { font-size: 16px; }
.story-list-excerpt { font-size: 16px; line-height: 1.8; }
.topics-lead, .topic p { font-size: 16px; line-height: 1.85; }
.topic-number { font-size: 12px; }
.editorial-copy p { font-size: 17px; line-height: 1.9; }

.breadcrumbs ol { font-size: 13px; }
.article-kicker { font-size: 12px; }
.article-author-label { font-size: 12px; }
.article-author-name { font-size: 18px; }
.article-author-role { font-size: 14px; line-height: 1.6; }
.article-author-note { font-size: 15px; line-height: 1.75; }
.article-body { font-size: 18px; line-height: 1.95; }
.article-body h2 { font-size: 26px; }
.article-body h3 { font-size: 21px; }
.article-body blockquote { font-size: 18px; line-height: 1.95; }
.article-body blockquote cite { font-size: 13px; }
.profile-snapshot-label, .profile-lens-label,
.relativity-figure-label { font-size: 12px; }
.profile-snapshot-list dt { font-size: 14px; }
.profile-snapshot-list dd { font-size: 16px; }
.person-timeline time, .relativity-timeline time { font-size: 14px; }
.article-body .person-timeline h3,
.article-body .relativity-timeline h3 { font-size: 19px; }
.article-body .person-timeline p,
.article-body .relativity-timeline p { font-size: 16px; line-height: 1.85; }
.article-source-note { font-size: 13px; }
.profile-lens li > span { font-size: 12px; }
.profile-lens li > strong { font-size: 16px; }
.profile-lens li > p { font-size: 14px; line-height: 1.8; }
.article-considerations strong { font-size: 15px; }
.article-considerations span { font-size: 16px; line-height: 1.85; }
.article-references li { font-size: 13px; line-height: 1.8; }

.relativity-first-answer p { font-size: 17px; }
.concept-figure figcaption { font-size: 13px; }
.relativity-family-grid time { font-size: 13px; }
.relativity-family-grid section > p,
.relativity-family-grid li { font-size: 15px; line-height: 1.8; }
.relativity-aside p:last-child { font-size: 16px; }
.diagram-heading { font-size: 15px; }
.diagram-note { font-size: 13px; }
.elevator-scene-title { font-size: 16px; }
.elevator-grid section > p:last-child { font-size: 14px; line-height: 1.75; }
.relativity-predictions dt { font-size: 16px; }
.relativity-predictions dd { font-size: 16px; line-height: 1.85; }
.gps-unit { font-size: 12px; }
.gps-effect strong { font-size: 15px; }
.gps-effect p { font-size: 14px; line-height: 1.7; }
.arcsecond-scale > div, .arcsecond-scale strong { font-size: 14px; }
.mercury-ledger > div span { font-size: 14px; }
.mercury-ledger > div strong { font-size: 16px; }
.gravity-comparison-grid .comparison-year { font-size: 12px; }
.gravity-comparison-grid section > p:last-child { font-size: 15px; line-height: 1.85; }
.article-callout-title { font-size: 12px; }
.article-callout p { font-size: 17px; }

.article-signature-name { font-size: 16px; }
.article-signature-role { font-size: 13px; }
.article-related-reading-kind { font-size: 13px; }
.article-related-reading-name { font-size: 19px; }
.article-related-reading-excerpt { font-size: 15px; line-height: 1.8; }
.article-cta-eyebrow { font-size: 12px; }
.article-cta-lead { font-size: 17px; line-height: 1.85; }
.article-cta-btn { min-height: 52px; font-size: 16px; }
.article-back-link { font-size: 15px; }
.footer-brand-copy { font-size: 14px; }
.footer-group h2 { font-size: 12px; }
.footer-group a { min-height: 40px; font-size: 14px; }
.footer-copy, .footer-legal a { font-size: 13px; }

@media (max-width: 760px) {
  .nav-link { font-size: 14px; }
  .nav-button { min-height: 42px; padding: 7px 15px; font-size: 14px; }
  .columns-hero-lead { font-size: 17px; }
  .featured-title-main { font-size: 23px; }
  .featured-title-sub { font-size: 17px; }
  .featured-excerpt { font-size: 16px; }
  .story-list-content .article-meta-cat,
  .story-list-content .article-meta-date,
  .story-list-content .article-meta-readtime { font-size: 13px; }
  .story-list-title { font-size: 18px; }
  .story-list-subtitle { font-size: 15px; }
  .editorial-copy p { font-size: 16px; }

  .article-author-name { font-size: 17px; }
  .article-author-role { font-size: 13px; }
  .article-author-note { font-size: 14px; line-height: 1.7; }
  .article-body { font-size: 18px; line-height: 1.9; }
  .article-body h2 { font-size: 24px; }
  .article-body h3 { font-size: 20px; }
  .article-body blockquote { font-size: 17px; }
  .profile-snapshot-list dt { font-size: 13px; }
  .profile-snapshot-list dd { font-size: 15px; }
  .person-timeline time, .relativity-timeline time { font-size: 13px; }
  .article-body .person-timeline h3,
  .article-body .relativity-timeline h3 { font-size: 18px; }
  .article-body .person-timeline p,
  .article-body .relativity-timeline p { font-size: 16px; }
  .profile-lens li > p { font-size: 14px; }
  .article-considerations span { font-size: 16px; }
  .relativity-first-answer p { font-size: 17px; }
  .concept-figure figcaption { font-size: 13px; }
  .elevator-grid section > p:last-child { font-size: 13px; }
  .relativity-predictions dd { font-size: 16px; }
  .arcsecond-scale strong { font-size: 14px; }
  .article-related-reading-kind { font-size: 13px; }
  .article-related-reading-name { font-size: 18px; }
  .article-related-reading-excerpt { font-size: 15px; }
  .article-callout p { font-size: 17px; }
  .article-cta-lead { font-size: 16px; }

  .profile-lens ol {
    grid-template-columns: 1fr;
    gap: 20px;
    margin-left: 7px;
    padding-left: 23px;
    border-left: 1px solid var(--line-strong);
  }
  .profile-lens li,
  .profile-lens li:first-child,
  .profile-lens li:nth-child(3),
  .profile-lens li:nth-child(4) {
    padding: 0;
    border: 0;
  }
  .profile-lens li > span { margin-bottom: 3px; }
  .profile-lens li > strong { margin-top: 0; font-size: 17px; }
  .profile-lens li > p { margin-top: 4px; font-size: 15px; line-height: 1.8; }
}

@media (hover: none) {
  .featured-card:hover, .nav-button:hover { transform: none; }
}
@media (prefers-reduced-motion: reduce) {
  * { scroll-behavior: auto !important; transition: none !important; }
}