:root {
  --bg: #f6f8f7;
  --surface: #ffffff;
  --surface-soft: #edf3f1;
  --ink: #14201e;
  --muted: #60706c;
  --line: #dce4e1;
  --primary: #087f73;
  --primary-dark: #05665d;
  --accent: #c64f3a;
  --gold: #a87808;
  --success: #27785f;
  --shadow: 0 10px 30px rgba(20, 32, 30, 0.08);
  --radius: 6px;
  --container: 1180px;
  --article: 760px;
  --header-height: 68px;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
  scroll-padding-top: calc(var(--header-height) + 24px);
}

body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif;
  font-size: 16px;
  line-height: 1.72;
  letter-spacing: 0;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

body.menu-open,
html.boot-pending body {
  overflow: hidden;
}

img {
  display: block;
  max-width: 100%;
}

a {
  color: var(--primary);
  text-underline-offset: 3px;
}

a:hover {
  color: var(--primary-dark);
}

button,
input,
select {
  font: inherit;
}

button,
a {
  -webkit-tap-highlight-color: transparent;
}

:focus-visible {
  outline: 3px solid rgba(8, 127, 115, 0.28);
  outline-offset: 3px;
}

[hidden] {
  display: none !important;
}

.skip-link {
  position: fixed;
  top: 8px;
  left: 12px;
  z-index: 2000;
  padding: 9px 13px;
  background: var(--surface);
  border: 1px solid var(--primary);
  border-radius: 4px;
  color: var(--ink);
  transform: translateY(-150%);
}

.skip-link:focus {
  transform: translateY(0);
}

.container {
  width: min(var(--container), calc(100% - 40px));
  margin-inline: auto;
}

.narrow {
  width: min(var(--article), calc(100% - 40px));
  margin-inline: auto;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 1000;
  height: var(--header-height);
  background: rgba(246, 248, 247, 0.96);
  border-bottom: 1px solid var(--line);
}

.header-inner {
  height: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  color: var(--ink);
  font-size: 17px;
  font-weight: 750;
  text-decoration: none;
  white-space: nowrap;
}

.brand-mark {
  width: 32px;
  height: 32px;
  display: grid;
  place-items: center;
  border-radius: 5px;
  background: var(--primary);
  color: #fff;
  font-size: 15px;
  font-weight: 800;
}

.site-nav {
  display: flex;
  align-items: center;
  gap: 3px;
}

.site-nav a {
  min-height: 42px;
  display: inline-flex;
  align-items: center;
  padding: 0 12px;
  border-radius: 4px;
  color: #34433f;
  font-size: 14px;
  font-weight: 600;
  text-decoration: none;
}

.site-nav a:hover,
.site-nav a[aria-current="page"] {
  background: var(--surface-soft);
  color: var(--primary-dark);
}

.nav-toggle {
  width: 44px;
  height: 44px;
  display: none;
  place-items: center;
  padding: 0;
  border: 1px solid var(--line);
  border-radius: 5px;
  background: var(--surface);
  color: var(--ink);
  cursor: pointer;
}

.nav-toggle-lines,
.nav-toggle-lines::before,
.nav-toggle-lines::after {
  width: 19px;
  height: 2px;
  display: block;
  background: currentColor;
  content: "";
  transition: transform 180ms ease, opacity 180ms ease;
}

.nav-toggle-lines::before {
  transform: translateY(-6px);
}

.nav-toggle-lines::after {
  transform: translateY(4px);
}

.menu-open .nav-toggle-lines {
  background: transparent;
}

.menu-open .nav-toggle-lines::before {
  transform: translateY(0) rotate(45deg);
}

.menu-open .nav-toggle-lines::after {
  transform: translateY(-2px) rotate(-45deg);
}

.nav-scrim {
  display: none;
}

.boot-screen {
  display: none;
}

.js.boot-pending .boot-screen,
.js.boot-ready .boot-screen {
  position: fixed;
  inset: 0;
  z-index: 3000;
  display: grid;
  place-items: center;
  background: var(--bg);
}

.boot-core {
  width: min(360px, calc(100% - 48px));
  text-align: center;
}

.boot-symbol {
  width: 58px;
  height: 58px;
  display: grid;
  place-items: center;
  margin: 0 auto 20px;
  border: 1px solid var(--primary);
  border-radius: 6px;
  color: var(--primary);
  font-size: 22px;
  font-weight: 800;
  animation: boot-pulse 900ms ease-in-out infinite alternate;
}

.boot-title {
  margin: 0;
  font-size: 22px;
  font-weight: 760;
}

.boot-status {
  margin: 8px 0 18px;
  color: var(--muted);
  font-size: 13px;
}

.boot-line {
  position: relative;
  width: 100%;
  height: 2px;
  overflow: hidden;
  background: var(--line);
}

.boot-line::after {
  position: absolute;
  inset: 0 auto 0 0;
  width: 42%;
  background: var(--primary);
  content: "";
  animation: boot-line 850ms ease-in-out infinite;
}

.boot-ready .boot-screen {
  opacity: 0;
  visibility: hidden;
  transition: opacity 220ms ease, visibility 0s linear 220ms;
}

.hero-actions-centered {
  justify-content: center;
}

.footer-bottom-compact {
  margin-top: 0;
}

.page-progress {
  position: fixed;
  top: 0;
  left: 0;
  z-index: 3100;
  width: 0;
  height: 3px;
  background: var(--accent);
  opacity: 0;
  pointer-events: none;
  transition: width 260ms ease, opacity 150ms ease;
}

.nav-pending .page-progress {
  width: 74%;
  opacity: 1;
}

.page-leaving .page-progress {
  width: 94%;
}

.page-main {
  opacity: 1;
  transform: translateY(0);
  transition: opacity 190ms ease, transform 190ms ease;
}

.page-leaving .page-main {
  opacity: 0.78;
  transform: translateY(-6px);
}

.hero {
  position: relative;
  height: min(680px, calc(100svh - 120px));
  min-height: 520px;
  overflow: hidden;
  background: #273431;
  color: #fff;
}

.hero::after {
  position: absolute;
  inset: 0;
  background: rgba(7, 20, 18, 0.58);
  content: "";
}

.hero-image {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
  object-position: center;
}

.hero-inner {
  position: relative;
  z-index: 1;
  height: 100%;
  display: flex;
  align-items: center;
}

.hero-copy {
  width: min(690px, 100%);
  padding-block: 54px;
}

.kicker {
  margin: 0 0 14px;
  color: #bfe9e2;
  font-size: 13px;
  font-weight: 700;
}

.hero h1 {
  max-width: 680px;
  margin: 0;
  font-size: 58px;
  line-height: 1.13;
  letter-spacing: 0;
}

.hero-lead {
  max-width: 620px;
  margin: 24px 0 30px;
  color: #e5efed;
  font-size: 18px;
  line-height: 1.78;
}

.hero-actions,
.section-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

.button {
  min-height: 44px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 9px 16px;
  border: 1px solid transparent;
  border-radius: 5px;
  font-weight: 700;
  text-decoration: none;
  cursor: pointer;
}

.button-primary {
  background: var(--primary);
  color: #fff;
}

.button-primary:hover {
  background: var(--primary-dark);
  color: #fff;
}

.button-light {
  background: rgba(255, 255, 255, 0.94);
  color: var(--ink);
}

.button-light:hover {
  background: #fff;
  color: var(--primary-dark);
}

.button-outline {
  border-color: var(--line);
  background: var(--surface);
  color: var(--ink);
}

.button-outline:hover {
  border-color: var(--primary);
  color: var(--primary-dark);
}

.section {
  padding-block: 78px;
}

.section-tight {
  padding-block: 54px;
}

.section-surface {
  background: var(--surface);
  border-block: 1px solid var(--line);
}

.section-ink {
  background: #172522;
  color: #fff;
}

.section-heading {
  display: flex;
  align-items: end;
  justify-content: space-between;
  gap: 28px;
  margin-bottom: 34px;
}

.section-heading > div {
  max-width: 720px;
}

.eyebrow {
  margin: 0 0 8px;
  color: var(--primary);
  font-size: 12px;
  font-weight: 750;
}

.section-ink .eyebrow {
  color: #82d4c8;
}

.section-heading h2,
.page-intro h1,
.article-header h1 {
  margin: 0;
  line-height: 1.24;
  letter-spacing: 0;
}

.section-heading h2 {
  font-size: 34px;
}

.section-heading p,
.page-intro p {
  margin: 12px 0 0;
  color: var(--muted);
}

.section-ink .section-heading p {
  color: #b9c9c5;
}

.text-link {
  display: inline-flex;
  align-items: center;
  gap: 7px;
  font-weight: 700;
  white-space: nowrap;
}

.learning-track {
  position: relative;
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 22px;
}

.learning-track::before {
  position: absolute;
  top: 31px;
  left: 10%;
  right: 10%;
  height: 2px;
  background: var(--line);
  content: "";
}

.track-step {
  position: relative;
  padding-top: 62px;
}

.track-number {
  position: absolute;
  top: 0;
  left: 0;
  z-index: 1;
  width: 64px;
  height: 64px;
  display: grid;
  place-items: center;
  border: 2px solid var(--surface);
  border-radius: 50%;
  background: var(--primary);
  color: #fff;
  font-size: 14px;
  font-weight: 800;
  box-shadow: 0 0 0 1px var(--primary);
}

.track-step:nth-child(2) .track-number {
  background: var(--gold);
  box-shadow: 0 0 0 1px var(--gold);
}

.track-step:nth-child(3) .track-number {
  background: var(--accent);
  box-shadow: 0 0 0 1px var(--accent);
}

.track-step h3 {
  margin: 20px 0 8px;
  font-size: 21px;
}

.track-step p {
  margin: 0 0 13px;
  color: var(--muted);
}

.topic-list,
.plain-list {
  margin: 0;
  padding-left: 20px;
}

.topic-list li,
.plain-list li {
  margin-block: 5px;
}

.card-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 18px;
}

.note-card,
.resource-card {
  min-width: 0;
  display: flex;
  flex-direction: column;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--surface);
  box-shadow: var(--shadow);
}

.note-card {
  padding: 22px;
}

.note-card:hover {
  border-color: #9fc7c1;
}

.card-meta,
.article-meta,
.crumbs {
  display: flex;
  flex-wrap: wrap;
  gap: 8px 14px;
  color: var(--muted);
  font-size: 13px;
}

.tag {
  display: inline-flex;
  align-items: center;
  min-height: 25px;
  padding: 2px 8px;
  border-radius: 4px;
  background: var(--surface-soft);
  color: var(--primary-dark);
  font-size: 12px;
  font-weight: 700;
}

.note-card h3,
.resource-card h3 {
  margin: 16px 0 9px;
  font-size: 20px;
  line-height: 1.38;
}

.note-card h3 a,
.resource-card h3 a {
  color: var(--ink);
  text-decoration: none;
}

.note-card h3 a:hover,
.resource-card h3 a:hover {
  color: var(--primary);
}

.note-card p,
.resource-card p {
  margin: 0 0 20px;
  color: var(--muted);
}

.note-card .text-link,
.resource-card .text-link {
  margin-top: auto;
}

.watch-list {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  border-top: 1px solid rgba(255, 255, 255, 0.15);
}

.watch-item {
  padding: 26px 26px 28px 0;
  border-bottom: 1px solid rgba(255, 255, 255, 0.15);
}

.watch-item + .watch-item {
  padding-left: 26px;
  border-left: 1px solid rgba(255, 255, 255, 0.15);
}

.watch-item time {
  color: #82d4c8;
  font-size: 12px;
  font-weight: 700;
}

.watch-item h3 {
  margin: 9px 0;
  font-size: 20px;
}

.watch-item p {
  margin: 0;
  color: #b9c9c5;
}

.split-feature {
  display: grid;
  grid-template-columns: minmax(0, 0.95fr) minmax(0, 1.05fr);
  gap: 48px;
  align-items: center;
}

.feature-image {
  width: 100%;
  aspect-ratio: 4 / 3;
  object-fit: cover;
  border-radius: var(--radius);
}

.feature-copy h2 {
  margin: 0 0 14px;
  font-size: 34px;
  line-height: 1.25;
}

.feature-copy p {
  color: var(--muted);
}

.page-intro {
  padding-block: 76px 50px;
  border-bottom: 1px solid var(--line);
  background: var(--surface);
}

.page-intro h1 {
  max-width: 820px;
  font-size: 46px;
}

.page-intro p {
  max-width: 720px;
  font-size: 17px;
}

.crumbs {
  margin-bottom: 20px;
}

.crumbs a {
  color: var(--muted);
}

.filters {
  display: grid;
  grid-template-columns: minmax(240px, 1fr) auto;
  gap: 18px;
  align-items: end;
  margin-bottom: 28px;
  padding: 18px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--surface);
}

.search-field {
  display: grid;
  gap: 7px;
  color: var(--muted);
  font-size: 13px;
  font-weight: 700;
}

.search-input {
  width: 100%;
  height: 46px;
  padding: 0 13px;
  border: 1px solid #bcc9c5;
  border-radius: 5px;
  background: #fff;
  color: var(--ink);
}

.search-input:focus {
  border-color: var(--primary);
  outline: 3px solid rgba(8, 127, 115, 0.15);
}

.filter-buttons {
  display: flex;
  flex-wrap: wrap;
  gap: 7px;
}

.filter-button {
  min-height: 42px;
  padding: 7px 12px;
  border: 1px solid var(--line);
  border-radius: 5px;
  background: var(--surface);
  color: var(--ink);
  font-weight: 650;
  cursor: pointer;
}

.filter-button:hover,
.filter-button[aria-pressed="true"] {
  border-color: var(--primary);
  background: var(--surface-soft);
  color: var(--primary-dark);
}

.results-bar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 18px;
  margin-bottom: 16px;
  color: var(--muted);
  font-size: 14px;
}

.empty-state {
  padding: 48px 20px;
  border-block: 1px solid var(--line);
  text-align: center;
}

.empty-state h2 {
  margin: 0 0 8px;
  font-size: 22px;
}

.empty-state p {
  margin: 0 0 18px;
  color: var(--muted);
}

.path-stages {
  display: grid;
  gap: 30px;
}

.path-stage {
  display: grid;
  grid-template-columns: 150px minmax(0, 1fr);
  gap: 34px;
  padding-block: 30px;
  border-top: 1px solid var(--line);
}

.stage-label {
  color: var(--primary);
  font-size: 13px;
  font-weight: 800;
}

.stage-label strong {
  display: block;
  margin-top: 4px;
  color: var(--ink);
  font-size: 28px;
}

.stage-content h2 {
  margin: 0 0 9px;
  font-size: 27px;
}

.stage-content > p {
  margin: 0 0 20px;
  color: var(--muted);
}

.stage-columns {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 20px;
}

.stage-columns h3 {
  margin: 0 0 7px;
  font-size: 15px;
}

.stage-columns p,
.stage-columns ul {
  margin: 0;
  color: var(--muted);
  font-size: 14px;
}

.article-header {
  padding-block: 62px 44px;
  border-bottom: 1px solid var(--line);
  background: var(--surface);
}

.article-header h1 {
  max-width: 880px;
  font-size: 44px;
}

.article-deck {
  max-width: 760px;
  margin: 16px 0 22px;
  color: var(--muted);
  font-size: 18px;
}

.article-layout {
  display: grid;
  grid-template-columns: minmax(0, var(--article)) 230px;
  gap: 58px;
  align-items: start;
  width: min(1070px, calc(100% - 40px));
  margin-inline: auto;
  padding-block: 54px 80px;
}

.article-body {
  min-width: 0;
  color: #24312e;
  font-size: 17px;
  line-height: 1.86;
}

.article-body h2 {
  margin: 54px 0 16px;
  color: var(--ink);
  font-size: 28px;
  line-height: 1.32;
}

.article-body h3 {
  margin: 34px 0 11px;
  color: var(--ink);
  font-size: 21px;
}

.article-body p,
.article-body ul,
.article-body ol {
  margin-block: 0 20px;
}

.article-body blockquote {
  margin: 30px 0;
  padding: 18px 22px;
  border-left: 4px solid var(--primary);
  background: var(--surface-soft);
  color: #34433f;
}

.article-body code {
  padding: 2px 5px;
  border-radius: 3px;
  background: #e7eeec;
  color: #9d3929;
  font-family: Consolas, "SFMono-Regular", monospace;
  font-size: 0.9em;
}

.article-aside {
  position: sticky;
  top: calc(var(--header-height) + 24px);
  padding-left: 20px;
  border-left: 1px solid var(--line);
}

.article-aside h2 {
  margin: 0 0 12px;
  font-size: 14px;
}

.article-aside ol {
  margin: 0;
  padding-left: 18px;
}

.article-aside li {
  margin-block: 8px;
  color: var(--muted);
  font-size: 13px;
}

.article-aside a {
  color: inherit;
  text-decoration: none;
}

.source-list {
  padding-top: 24px;
  border-top: 1px solid var(--line);
}

.reading-progress {
  position: fixed;
  top: var(--header-height);
  left: 0;
  z-index: 990;
  width: 0;
  height: 2px;
  background: var(--primary);
  pointer-events: none;
}

.model-table-wrap {
  overflow-x: auto;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--surface);
}

.model-table {
  width: 100%;
  min-width: 760px;
  border-collapse: collapse;
}

.model-table th,
.model-table td {
  padding: 15px 17px;
  border-bottom: 1px solid var(--line);
  text-align: left;
  vertical-align: top;
}

.model-table th {
  background: var(--surface-soft);
  color: #40504c;
  font-size: 13px;
}

.model-table tr:last-child td {
  border-bottom: 0;
}

.notice {
  margin-bottom: 26px;
  padding: 16px 18px;
  border-left: 4px solid var(--gold);
  background: #fff8df;
  color: #55471d;
}

.resource-card {
  padding: 20px;
}

.about-principles {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 18px;
}

.principle {
  padding-top: 18px;
  border-top: 3px solid var(--primary);
}

.principle:nth-child(2) {
  border-top-color: var(--gold);
}

.principle:nth-child(3) {
  border-top-color: var(--accent);
}

.principle h3 {
  margin: 0 0 7px;
}

.principle p {
  margin: 0;
  color: var(--muted);
}

.site-footer {
  padding-block: 42px 34px;
  border-top: 1px solid var(--line);
  background: #edf2f0;
}

.footer-grid {
  display: grid;
  grid-template-columns: 1.2fr 0.8fr;
  gap: 40px;
  align-items: start;
}

.footer-brand {
  margin: 0 0 6px;
  font-size: 17px;
  font-weight: 780;
}

.footer-copy {
  max-width: 580px;
  margin: 0;
  color: var(--muted);
  font-size: 14px;
}

.footer-links {
  display: flex;
  flex-wrap: wrap;
  justify-content: flex-end;
  gap: 8px 18px;
}

.footer-links a {
  color: #41514d;
  font-size: 14px;
  text-decoration: none;
}

.footer-bottom {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: 10px 24px;
  margin-top: 30px;
  padding-top: 18px;
  border-top: 1px solid #d2dcda;
  color: var(--muted);
  font-size: 13px;
}

.footer-bottom p {
  margin: 0;
}

.footer-bottom a {
  color: inherit;
}

.back-to-top {
  position: fixed;
  right: max(18px, env(safe-area-inset-right));
  bottom: max(18px, env(safe-area-inset-bottom));
  z-index: 900;
  width: 44px;
  height: 44px;
  display: grid;
  place-items: center;
  border: 1px solid var(--line);
  border-radius: 50%;
  background: var(--surface);
  color: var(--ink);
  box-shadow: var(--shadow);
  font-size: 20px;
  cursor: pointer;
  opacity: 0;
  visibility: hidden;
  transform: translateY(8px);
  transition: opacity 160ms ease, transform 160ms ease, visibility 0s linear 160ms;
}

.back-to-top.visible {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
  transition-delay: 0s;
}

.not-found {
  min-height: calc(100svh - var(--header-height));
  display: grid;
  place-items: center;
  padding-block: 60px;
}

.not-found-inner {
  max-width: 650px;
  text-align: center;
}

.not-found-code {
  margin: 0;
  color: var(--primary);
  font-size: 84px;
  font-weight: 850;
  line-height: 1;
}

.not-found h1 {
  margin: 16px 0 10px;
  font-size: 34px;
}

.not-found p {
  margin: 0 0 25px;
  color: var(--muted);
}

@keyframes boot-pulse {
  from { opacity: 0.68; transform: translateY(2px); }
  to { opacity: 1; transform: translateY(-2px); }
}

@keyframes boot-line {
  0% { transform: translateX(-110%); }
  100% { transform: translateX(340%); }
}

@media (max-width: 1023px) {
  :root {
    --header-height: 64px;
  }

  .nav-toggle {
    display: grid;
  }

  .site-nav {
    position: fixed;
    top: var(--header-height);
    right: 0;
    bottom: 0;
    z-index: 1100;
    width: min(360px, 88vw);
    display: flex;
    align-items: stretch;
    flex-direction: column;
    gap: 3px;
    padding: 20px;
    background: var(--surface);
    box-shadow: -14px 0 38px rgba(20, 32, 30, 0.15);
    transform: translateX(105%);
    visibility: hidden;
    transition: transform 200ms ease, visibility 0s linear 200ms;
  }

  .site-nav a {
    min-height: 48px;
    padding-inline: 14px;
    font-size: 16px;
  }

  .menu-open .site-nav {
    transform: translateX(0);
    visibility: visible;
    transition-delay: 0s;
  }

  .nav-scrim {
    position: fixed;
    inset: var(--header-height) 0 0;
    z-index: 1050;
    display: block;
    border: 0;
    background: rgba(10, 22, 20, 0.46);
    opacity: 0;
    visibility: hidden;
    transition: opacity 180ms ease, visibility 0s linear 180ms;
  }

  .menu-open .nav-scrim {
    opacity: 1;
    visibility: visible;
    transition-delay: 0s;
  }

  .card-grid,
  .watch-list,
  .about-principles {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .watch-item:nth-child(3) {
    padding-left: 0;
    border-left: 0;
  }

  .article-layout {
    grid-template-columns: minmax(0, 1fr);
  }

  .article-aside {
    position: static;
    grid-row: 1;
    padding: 18px;
    border: 1px solid var(--line);
    border-radius: var(--radius);
    background: var(--surface);
  }
}

@media (max-width: 767px) {
  .container,
  .narrow,
  .article-layout {
    width: min(100% - 28px, var(--container));
  }

  .brand {
    font-size: 15px;
  }

  .hero {
    height: min(620px, calc(100svh - 112px));
    min-height: 510px;
  }

  .hero-image {
    object-position: 56% center;
  }

  .hero::after {
    background: rgba(7, 20, 18, 0.66);
  }

  .hero h1 {
    font-size: 38px;
  }

  .hero-lead {
    font-size: 16px;
  }

  .section {
    padding-block: 52px;
  }

  .section-tight {
    padding-block: 42px;
  }

  .section-heading {
    align-items: start;
    flex-direction: column;
    gap: 15px;
    margin-bottom: 26px;
  }

  .section-heading h2,
  .feature-copy h2 {
    font-size: 28px;
  }

  .learning-track,
  .card-grid,
  .watch-list,
  .split-feature,
  .about-principles,
  .stage-columns,
  .footer-grid {
    grid-template-columns: minmax(0, 1fr);
  }

  .learning-track {
    gap: 16px;
  }

  .learning-track::before {
    top: 24px;
    bottom: 24px;
    left: 24px;
    right: auto;
    width: 2px;
    height: auto;
  }

  .track-step {
    min-height: 88px;
    padding: 0 0 24px 78px;
  }

  .track-number {
    width: 50px;
    height: 50px;
  }

  .track-step h3 {
    margin-top: 0;
  }

  .watch-item,
  .watch-item + .watch-item,
  .watch-item:nth-child(3) {
    padding: 22px 0;
    border-left: 0;
  }

  .split-feature {
    gap: 30px;
  }

  .feature-image {
    aspect-ratio: 16 / 10;
  }

  .page-intro {
    padding-block: 54px 38px;
  }

  .page-intro h1,
  .article-header h1 {
    font-size: 34px;
  }

  .filters {
    grid-template-columns: minmax(0, 1fr);
    padding: 14px;
  }

  .filter-buttons {
    overflow-x: auto;
    flex-wrap: nowrap;
    padding-bottom: 3px;
  }

  .filter-button {
    flex: 0 0 auto;
  }

  .path-stage {
    grid-template-columns: minmax(0, 1fr);
    gap: 15px;
  }

  .article-header {
    padding-block: 46px 34px;
  }

  .article-deck {
    font-size: 16px;
  }

  .article-layout {
    gap: 32px;
    padding-block: 36px 56px;
  }

  .article-body {
    font-size: 16px;
  }

  .article-body h2 {
    font-size: 25px;
  }

  .footer-links {
    justify-content: flex-start;
  }

  .footer-bottom {
    flex-direction: column;
  }

  .not-found-code {
    font-size: 64px;
  }
}

@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }

  *,
  *::before,
  *::after {
    scroll-behavior: auto !important;
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
}