:root {
  --bg: #f7f5ef;
  --surface: #ffffff;
  --ink: #1d1a2b;
  --muted: #6f6b7a;
  --soft: #8a8492;
  --line: #e9e4da;
  --coral: #ff6b5e;
  --peach: #ff7a59;
  --pink: #ff5e87;
  --violet: #7c5cff;
  --sky: #1f9fb8;
  --green: #2f9e61;
  --yellow: #d99a17;
  --rose: #e35b7d;
  --container: 1140px;
  --shadow-sm: 0 8px 24px rgba(60, 45, 90, 0.06);
  --shadow-md: 0 24px 60px rgba(60, 45, 90, 0.10);
  --shadow-lg: 0 34px 80px rgba(60, 45, 90, 0.14);
}

* { margin: 0; padding: 0; box-sizing: border-box; }
[hidden] { display: none !important; }

html { scroll-behavior: smooth; scroll-padding-top: 92px; }

body {
  font-family: -apple-system, BlinkMacSystemFont, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Segoe UI", sans-serif;
  color: var(--ink);
  line-height: 1.7;
  background:
    radial-gradient(900px 560px at 90% -6%, rgba(255, 176, 141, 0.20), transparent 62%),
    radial-gradient(760px 520px at -8% 10%, rgba(177, 160, 255, 0.16), transparent 60%),
    var(--bg);
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}

::selection { background: rgba(255, 122, 89, 0.28); color: var(--ink); }
a { color: inherit; text-decoration: none; }
button { font: inherit; color: inherit; border: none; background: none; cursor: pointer; }
svg { display: block; }
ul { list-style: none; }

.icon {
  width: 20px;
  height: 20px;
  fill: none;
  stroke: currentColor;
  stroke-width: 1.8;
  stroke-linecap: round;
  stroke-linejoin: round;
  flex: none;
}

.container {
  width: min(calc(100% - 48px), var(--container));
  margin-inline: auto;
}

/* Header */
.site-header {
  position: sticky;
  top: 0;
  z-index: 60;
  background: rgba(247, 245, 239, 0.86);
  border-bottom: 1px solid rgba(29, 26, 43, 0.06);
  backdrop-filter: blur(18px);
  -webkit-backdrop-filter: blur(18px);
}

.nav {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 72px;
  position: relative;
  gap: 18px;
}

.logo { display: inline-flex; align-items: center; gap: 10px; flex: none; }

.logo-mark {
  width: 36px;
  height: 36px;
  border-radius: 11px;
  background: linear-gradient(135deg, var(--coral), var(--violet));
  display: grid;
  place-items: center;
  box-shadow: 0 7px 18px rgba(255, 107, 94, 0.3);
}

.logo-mark svg { width: 19px; height: 19px; }

.logo-text {
  display: flex;
  flex-direction: column;
  line-height: 1.1;
  font-size: 17px;
  font-weight: 800;
}

.logo-text small {
  margin-top: 3px;
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 0.26em;
  color: var(--soft);
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 22px;
  font-size: 13px;
  color: #5b5666;
}

.nav-links a {
  position: relative;
  padding: 6px 0;
  white-space: nowrap;
  transition: color 0.2s;
}

.nav-links a::after {
  content: "";
  position: absolute;
  left: 0;
  right: 100%;
  bottom: 1px;
  height: 2px;
  border-radius: 2px;
  background: linear-gradient(90deg, var(--coral), var(--violet));
  transition: right 0.24s ease;
}

.nav-links a:hover, .nav-links a.active { color: var(--ink); }
.nav-links a:hover::after, .nav-links a.active::after { right: 0; }

.nav-right { display: flex; align-items: center; gap: 10px; }

.menu-btn {
  display: none;
  width: 42px;
  height: 42px;
  border: 1px solid var(--line);
  border-radius: 12px;
  background: #fff;
  place-items: center;
}

.mobile-only { display: none; }

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 11px 20px;
  border-radius: 999px;
  font-weight: 700;
  font-size: 13px;
  white-space: nowrap;
  transition: transform 0.22s ease, box-shadow 0.22s ease, background 0.22s ease, border-color 0.22s ease;
}

.btn .icon { width: 15px; height: 15px; }

.btn-dark {
  background: var(--ink);
  color: #fff;
  box-shadow: 0 8px 20px rgba(29, 26, 43, 0.18);
}

.btn-dark:hover { transform: translateY(-2px); background: #2d2940; }

.btn-primary {
  background: linear-gradient(135deg, var(--peach), var(--pink));
  color: #fff;
  box-shadow: 0 10px 24px rgba(255, 94, 135, 0.25);
}

.btn-primary:hover { transform: translateY(-2px); box-shadow: 0 14px 30px rgba(255, 94, 135, 0.35); }

.btn-soft {
  background: #fff;
  color: var(--ink);
  border: 1px solid var(--line);
  box-shadow: var(--shadow-sm);
}

.btn-soft:hover { transform: translateY(-2px); border-color: #d4cdc1; }

.btn-sm { padding: 9px 16px; font-size: 12px; }

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  margin-bottom: 12px;
  font-size: 12px;
  font-weight: 800;
  letter-spacing: 0.22em;
  text-transform: uppercase;
  color: var(--coral);
}

.eyebrow::before {
  content: "";
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: currentColor;
}

/* Course hero */
.course-hero {
  position: relative;
  padding: 56px 0 52px;
  border-bottom: 1px solid var(--line);
  background:
    radial-gradient(620px 340px at 92% 0%, var(--tint, #fff0e8), transparent 66%),
    linear-gradient(180deg, #fffdfa, var(--bg));
}

.breadcrumb {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 7px;
  margin-bottom: 28px;
  font-size: 12px;
  color: var(--soft);
}

.breadcrumb a:hover { color: var(--ink); }
.breadcrumb i { font-style: normal; color: #c4bdce; }

.course-hero-grid {
  display: grid;
  grid-template-columns: 1.2fr 0.8fr;
  gap: 54px;
  align-items: center;
}

.layer-tag {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 6px 12px;
  border-radius: 999px;
  background: var(--tint, #fff0e8);
  color: var(--accent, var(--coral));
  font-size: 12px;
  font-weight: 800;
  letter-spacing: 0.16em;
}

.layer-tag::before {
  content: "";
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: currentColor;
}

.course-hero h1 {
  margin: 16px 0 14px;
  font-size: clamp(2rem, 4vw, 3.2rem);
  line-height: 1.2;
  letter-spacing: -0.03em;
  font-weight: 800;
}

.course-hero p.lead {
  max-width: 660px;
  font-size: 14.5px;
  line-height: 1.95;
  color: var(--muted);
}

.meta-chips { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 22px; }

.meta-chips span {
  padding: 5px 10px;
  border-radius: 999px;
  background: #fff;
  border: 1px solid var(--line);
  font-size: 12px;
  color: var(--soft);
}

.hero-acceptance {
  padding: 23px;
  border-radius: 20px;
  border: 1px solid var(--line);
  border-top: 4px solid var(--accent, var(--coral));
  background: #fff;
  box-shadow: var(--shadow-md);
}

.hero-acceptance > span {
  display: block;
  font-size: 12px;
  font-weight: 800;
  letter-spacing: 0.18em;
  color: var(--accent, var(--coral));
  text-transform: uppercase;
}

.hero-acceptance h2 {
  margin: 10px 0 8px;
  font-size: 15px;
  line-height: 1.45;
}

.hero-acceptance p {
  font-size: 12px;
  line-height: 1.8;
  color: var(--muted);
}

.hero-acceptance a {
  display: inline-flex;
  align-items: center;
  gap: 5px;
  margin-top: 14px;
  font-size: 12px;
  font-weight: 700;
  color: var(--accent, var(--coral));
}

/* Layout */
.course-layout {
  display: grid;
  grid-template-columns: 238px minmax(0, 1fr);
  gap: 50px;
  align-items: start;
  padding: 54px 0 88px;
}

.course-sidebar { position: sticky; top: 96px; }
.side-block + .side-block { margin-top: 26px; }

.side-title {
  margin-bottom: 9px;
  font-size: 12px;
  font-weight: 800;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--soft);
}

.module-nav { display: grid; gap: 2px; }

.module-nav a {
  display: flex;
  align-items: baseline;
  gap: 8px;
  padding: 6px 9px;
  border-radius: 8px;
  font-size: 12px;
  line-height: 1.45;
  color: #716b7a;
  transition: 0.18s;
}

.module-nav a:hover { background: #fff; color: var(--ink); }

.module-nav a.active {
  background: var(--tint, #fff0e8);
  color: var(--accent, var(--coral));
  font-weight: 700;
}

.module-nav b {
  font-family: "SF Mono", "Menlo", ui-monospace, monospace;
  font-size: 12px;
  font-weight: 700;
  opacity: 0.65;
  flex: none;
}

.toc { display: grid; gap: 1px; }

.toc a {
  padding: 4px 9px;
  border-left: 2px solid transparent;
  font-size: 12px;
  color: #847e8c;
  transition: 0.18s;
}

.toc a:hover { color: var(--ink); border-left-color: var(--accent, var(--coral)); }

.course-content { min-width: 0; }

/* Sections */
.lesson-section {
  padding-bottom: 40px;
  margin-bottom: 36px;
  border-bottom: 1px solid var(--line);
}

.lesson-section:last-of-type { border-bottom: none; }

.lesson-section h2 {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-bottom: 14px;
  font-size: 24px;
  line-height: 1.35;
  letter-spacing: -0.02em;
}

.lesson-section h2 .num {
  display: inline-flex;
  padding: 3px 7px;
  border-radius: 6px;
  background: var(--tint, #fff0e8);
  color: var(--accent, var(--coral));
  font-family: "SF Mono", "Menlo", ui-monospace, monospace;
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 0.06em;
}

.lesson-section h3 { margin: 24px 0 8px; font-size: 16.5px; line-height: 1.45; }
.lesson-section h4 { margin: 18px 0 6px; font-size: 13.5px; color: var(--ink); }

.lesson-section p {
  margin: 10px 0;
  font-size: 13.3px;
  line-height: 1.95;
  color: #5d5866;
}

.lesson-section strong { color: var(--ink); }
.lesson-section em { font-style: normal; color: var(--accent, var(--coral)); font-weight: 600; }

.lesson-section ul, .lesson-section ol {
  display: grid;
  gap: 7px;
  margin: 12px 0;
  font-size: 13px;
  color: #5d5866;
}

.lesson-section ul li { position: relative; padding-left: 16px; }

.lesson-section ul li::before {
  content: "•";
  position: absolute;
  left: 0;
  color: var(--accent, var(--coral));
  font-weight: 800;
}

.lesson-section ol { padding-left: 19px; list-style: decimal; }
.lesson-section ol li { padding-left: 2px; }
.lesson-section ol li::marker { color: var(--accent, var(--coral)); font-weight: 700; }

/* Tables */
.table-wrap { overflow-x: auto; margin: 16px 0; border-radius: 14px; border: 1px solid var(--line); }

.data-table {
  width: 100%;
  min-width: 600px;
  border-collapse: collapse;
  font-size: 12px;
  background: #fff;
}

.data-table th {
  padding: 10px 12px;
  background: var(--tint, #fff0e8);
  color: var(--ink);
  text-align: left;
  font-size: 12px;
  font-weight: 800;
  letter-spacing: 0.03em;
  vertical-align: bottom;
}

.data-table td {
  padding: 10px 12px;
  border-top: 1px solid var(--line);
  color: #5d5866;
  line-height: 1.7;
  vertical-align: top;
}

.data-table tbody tr:nth-child(even) td { background: #fdfcf9; }
.data-table code { font-size: 12px; }

/* Callouts and code */
.callout {
  margin: 16px 0;
  padding: 14px 16px;
  border-left: 3px solid var(--accent, var(--coral));
  border-radius: 0 12px 12px 0;
  background: var(--tint, #fff0e8);
  font-size: 12.3px;
  line-height: 1.85;
  color: #5d5866;
}

.callout strong { color: var(--accent, var(--coral)); }
.callout.warn { background: #fff8e6; border-left-color: var(--yellow); }
.callout.warn strong { color: #9a6b0b; }

.code {
  display: block;
  margin: 14px 0;
  padding: 14px 16px;
  border-radius: 12px;
  background: #1d1a2b;
  color: #f1eeff;
  font-family: "SF Mono", "Menlo", "Consolas", ui-monospace, monospace;
  font-size: 12px;
  line-height: 1.85;
  white-space: pre-wrap;
  overflow-wrap: anywhere;
}

.code .c-comment { color: #918aa6; }
.code .c-key { color: #ffb199; }
.code .c-val { color: #b9e6c8; }

code {
  padding: 1px 5px;
  border-radius: 4px;
  background: #f2eee6;
  color: #7c4a3a;
  font-family: "SF Mono", "Menlo", ui-monospace, monospace;
  font-size: 0.9em;
}

/* Acceptance */
.acceptance {
  padding: 26px;
  border-radius: 20px;
  border: 1px solid var(--line);
  border-top: 4px solid var(--accent, var(--coral));
  background: linear-gradient(150deg, var(--tint, #fff0e8), #fff 70%);
  box-shadow: var(--shadow-sm);
}

.acceptance h2 {
  display: flex;
  align-items: center;
  gap: 9px;
  margin-bottom: 10px;
  font-size: 19px;
}

.acceptance h2 .icon { width: 20px; height: 20px; color: var(--accent, var(--coral)); }

.acceptance > p {
  font-size: 12.8px;
  line-height: 1.9;
  color: #5d5866;
}

.acceptance .deliverable {
  margin: 15px 0;
  padding: 13px 15px;
  border-radius: 12px;
  background: rgba(255, 255, 255, 0.7);
  border: 1px dashed rgba(29, 26, 43, 0.14);
  font-size: 12px;
  line-height: 1.8;
}

.acceptance .deliverable strong { color: var(--accent, var(--coral)); }

.checklist-head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  margin: 16px 0 8px;
  font-size: 12px;
  font-weight: 800;
  letter-spacing: 0.08em;
  color: var(--soft);
  text-transform: uppercase;
}

.checklist { display: grid; gap: 8px; }

.checklist label {
  display: flex;
  align-items: flex-start;
  gap: 9px;
  font-size: 12.3px;
  line-height: 1.65;
  color: #4f4a58;
  cursor: pointer;
}

.checklist input {
  width: 15px;
  height: 15px;
  margin-top: 2px;
  accent-color: var(--accent, var(--coral));
  flex: none;
  cursor: pointer;
}

.checklist label:has(input:checked) { color: var(--soft); text-decoration: line-through; }

/* Practice steps */
.steps {
  display: grid;
  gap: 10px;
  margin: 14px 0;
  counter-reset: step;
}

.step {
  display: flex;
  gap: 12px;
  align-items: flex-start;
  padding: 12px 14px;
  border: 1px solid var(--line);
  border-radius: 12px;
  background: #fff;
  font-size: 12.3px;
  line-height: 1.75;
  color: #5d5866;
}

.step::before {
  counter-increment: step;
  content: counter(step, decimal-leading-zero);
  font-family: "SF Mono", "Menlo", ui-monospace, monospace;
  font-size: 12px;
  font-weight: 700;
  color: var(--accent, var(--coral));
  flex: none;
  padding-top: 2px;
}

/* Self test */
.self-tests { display: grid; gap: 8px; margin-top: 14px; }

.self-test {
  border: 1px solid var(--line);
  border-radius: 12px;
  background: #fff;
  overflow: hidden;
}

.self-test summary {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 14px;
  padding: 13px 15px;
  list-style: none;
  cursor: pointer;
  font-size: 12.3px;
  font-weight: 600;
  line-height: 1.6;
}

.self-test summary::-webkit-details-marker { display: none; }

.self-test summary::after {
  content: "+";
  color: var(--accent, var(--coral));
  font-size: 17px;
  font-weight: 400;
  flex: none;
}

.self-test[open] summary::after { content: "−"; }

.self-test .answer {
  padding: 11px 15px 14px;
  border-top: 1px dashed var(--line);
  font-size: 12px;
  line-height: 1.85;
  color: var(--muted);
}

/* Pager */
.module-pager {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 12px;
  margin-top: 8px;
}

.pager-card {
  display: block;
  padding: 16px 18px;
  border: 1px solid var(--line);
  border-radius: 14px;
  background: #fff;
  transition: 0.22s;
}

.pager-card:hover { transform: translateY(-2px); border-color: var(--accent, var(--coral)); box-shadow: var(--shadow-sm); }
.pager-card span { font-size: 12px; font-weight: 700; letter-spacing: 0.12em; color: var(--soft); text-transform: uppercase; }
.pager-card strong { display: block; margin-top: 4px; font-size: 13px; }
.pager-card.next { text-align: right; }
.pager-card.placeholder { visibility: hidden; }

/* Curriculum hub */
.hub-hero {
  padding: 64px 0 58px;
  border-bottom: 1px solid var(--line);
  background:
    radial-gradient(700px 360px at 88% 0%, #ffe4ec, transparent 64%),
    radial-gradient(560px 300px at 4% 20%, #e8e1ff, transparent 64%),
    linear-gradient(180deg, #fffdfa, var(--bg));
}

.hub-hero-grid {
  display: grid;
  grid-template-columns: 1.15fr 0.85fr;
  gap: 54px;
  align-items: center;
}

.hub-hero h1 {
  margin: 16px 0 14px;
  font-size: clamp(2.2rem, 4.4vw, 3.5rem);
  line-height: 1.18;
  letter-spacing: -0.035em;
  font-weight: 800;
}

.hub-hero p { max-width: 650px; font-size: 14.5px; line-height: 1.95; color: var(--muted); }

.hub-stats {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 10px;
  margin-top: 26px;
  max-width: 520px;
}

.hub-stat {
  padding: 14px;
  border-radius: 14px;
  background: #fff;
  border: 1px solid var(--line);
  box-shadow: var(--shadow-sm);
}

.hub-stat strong { display: block; font-size: 22px; line-height: 1.2; letter-spacing: -0.02em; }
.hub-stat span { display: block; margin-top: 3px; font-size: 12px; color: var(--soft); }

.hub-side {
  padding: 24px;
  border-radius: 22px;
  background: #fff;
  border: 1px solid var(--line);
  box-shadow: var(--shadow-md);
}

.hub-side > span {
  display: block;
  font-size: 12px;
  font-weight: 800;
  letter-spacing: 0.16em;
  color: var(--coral);
  text-transform: uppercase;
}

.hub-side h2 { margin: 9px 0 12px; font-size: 16px; line-height: 1.5; }

.hub-side ol { display: grid; gap: 8px; padding-left: 18px; font-size: 12px; color: var(--muted); }
.hub-side ol li::marker { color: var(--coral); font-weight: 700; }

.hub-list { padding: 54px 0 84px; }

.hub-list-head {
  display: flex;
  align-items: flex-end;
  justify-content: space-between;
  gap: 20px;
  margin-bottom: 26px;
}

.hub-list-head h2 { font-size: clamp(1.7rem, 3vw, 2.3rem); letter-spacing: -0.025em; }
.hub-list-head p { margin-top: 8px; font-size: 12.5px; color: var(--muted); }

.module-list { display: grid; gap: 10px; }

.module-row {
  display: grid;
  grid-template-columns: 64px minmax(0, 1fr) auto;
  gap: 20px;
  align-items: center;
  padding: 22px 24px;
  border: 1px solid var(--line);
  border-radius: 18px;
  background: #fff;
  transition: transform 0.22s ease, box-shadow 0.22s ease, border-color 0.22s ease;
}

.module-row:hover {
  transform: translateX(4px);
  border-color: var(--accent, var(--coral));
  box-shadow: var(--shadow-sm);
}

.module-num {
  font-family: "SF Mono", "Menlo", ui-monospace, monospace;
  font-size: 22px;
  font-weight: 800;
  letter-spacing: -0.03em;
  color: var(--accent, var(--coral));
  opacity: 0.85;
}

.module-info h3 { font-size: 17px; letter-spacing: -0.01em; }
.module-info p { margin-top: 5px; font-size: 12px; line-height: 1.75; color: var(--muted); }

.module-tags { display: flex; flex-wrap: wrap; gap: 5px; margin-top: 10px; }

.module-tag {
  padding: 3px 8px;
  border-radius: 999px;
  background: var(--tint, #fff0e8);
  color: var(--accent, var(--coral));
  font-size: 12px;
  font-weight: 700;
}

.module-go {
  display: flex;
  align-items: center;
  gap: 7px;
  font-size: 12px;
  font-weight: 700;
  color: var(--accent, var(--coral));
  white-space: nowrap;
}

.module-go .icon { width: 14px; height: 14px; }

/* Footer */
footer { border-top: 1px solid rgba(29, 26, 43, 0.07); padding: 34px 0 36px; }

.footer-grid {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 24px;
  flex-wrap: wrap;
}

.footer-brand p { margin-top: 10px; font-size: 12px; color: var(--soft); }

.footer-links { display: flex; flex-wrap: wrap; gap: 20px; font-size: 12px; color: #77717f; }
.footer-links a:hover { color: var(--ink); }

.footer-bottom {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  flex-wrap: wrap;
  margin-top: 26px;
  padding-top: 16px;
  border-top: 1px solid rgba(29, 26, 43, 0.06);
  font-size: 12px;
  color: #99939f;
}

/* Responsive */
@media (max-width: 1080px) {
  .nav-links { gap: 16px; font-size: 12.5px; }
}

@media (max-width: 960px) {
  .nav-links {
    position: fixed;
    top: 72px;
    left: 0;
    right: 0;
    display: none;
    flex-direction: column;
    align-items: stretch;
    gap: 2px;
    padding: 14px 24px 22px;
    background: #fffdf9;
    border-bottom: 1px solid var(--line);
    box-shadow: 0 26px 50px rgba(60, 45, 90, 0.12);
  }

  .site-header.open .nav-links { display: flex; }
  .nav-links a { padding: 11px 4px; }
  .nav-links a::after { display: none; }
  .nav-cta { display: none; }
  .menu-btn { display: grid; }
  .mobile-only { display: inline-flex; color: var(--coral) !important; font-weight: 700; }

  .course-hero, .hub-hero { padding: 42px 0 40px; }
  .course-hero-grid, .hub-hero-grid { grid-template-columns: 1fr; gap: 30px; }
  .hero-acceptance { max-width: 560px; }

  .course-layout { grid-template-columns: 1fr; gap: 32px; padding: 38px 0 70px; }
  .course-sidebar { position: static; }
  .module-nav { grid-template-columns: repeat(2, 1fr); }
  .toc { display: none; }
  .side-block + .side-block { margin-top: 18px; }

  .module-row { grid-template-columns: 52px minmax(0, 1fr); }
  .module-go { grid-column: 2; }

  .hub-stats { max-width: none; }
}

@media (max-width: 640px) {
  .container { width: calc(100% - 40px); }
  .course-hero h1 { font-size: clamp(1.8rem, 8.5vw, 2.5rem); }
  .course-hero p.lead { font-size: 13px; }
  .course-hero-grid { gap: 24px; }
  .hero-acceptance { padding: 18px; }
  .lesson-section h2 { font-size: 21px; }
  .lesson-section p { font-size: 12.8px; }
  .acceptance { padding: 20px 17px; }
  .module-pager { grid-template-columns: 1fr; }
  .pager-card.next { text-align: left; }

  .hub-stats { grid-template-columns: 1fr 1fr; }
  .hub-stat:last-child { grid-column: 1 / -1; }
  .hub-list-head { display: block; }
  .module-row { padding: 18px; gap: 14px; grid-template-columns: 40px minmax(0, 1fr); }
  .module-num { font-size: 17px; }
  .module-info h3 { font-size: 15.5px; }
  .module-info p { font-size: 12px; }
  .module-tags { display: none; }
  .module-go { font-size: 12px; }
}

/* ============================================================
   Readability & simplification pass
   ============================================================ */
:root {
  --bg: #f7f5ef;
  --surface: #ffffff;
  --ink: #1d1a2b;
  --muted: #514c5c;
  --soft: #6b6575;
  --line: #e1dcd2;
  --coral: #c8473a;
  --peach: #c25537;
  --pink: #b83b5e;
  --violet: #5a3fc7;
  --sky: #0e6f80;
  --green: #236b43;
  --yellow: #8a5a00;
  --rose: #a93b58;
  --container: 1200px;
  --shadow-sm: 0 4px 12px rgba(29, 26, 43, 0.06);
  --shadow-md: 0 10px 26px rgba(29, 26, 43, 0.08);
  --shadow-lg: 0 14px 34px rgba(29, 26, 43, 0.10);
}

body {
  background: var(--bg);
  font-size: 16px;
  line-height: 1.8;
}

h1 { font-size: clamp(2.2rem, 4vw, 3.4rem) !important; line-height: 1.22 !important; }
h2 { font-size: clamp(1.7rem, 3vw, 2.3rem) !important; line-height: 1.32 !important; }
h3 { font-size: 18px !important; line-height: 1.45 !important; }
p, li { font-size: 16px; line-height: 1.8; }

.course-hero, .hub-hero {
  background: #fff !important;
  border-bottom: 1px solid var(--line);
}

.course-hero h1, .hub-hero h1 { letter-spacing: -0.03em; }
.course-hero p.lead, .hub-hero p { font-size: 16px !important; line-height: 1.8 !important; color: var(--muted) !important; }
.course-hero-grid, .hub-hero-grid { gap: 46px; }

.breadcrumb { font-size: 13px !important; }
.layer-tag { font-size: 12px !important; background: #f3f0e9 !important; color: var(--accent, var(--coral)) !important; }
.meta-chips span { font-size: 13px !important; }
.hero-acceptance { background: #fff; box-shadow: var(--shadow-sm); }
.hero-acceptance > span { font-size: 12px !important; }
.hero-acceptance h2 { font-size: 18px !important; }
.hero-acceptance p { font-size: 15px !important; line-height: 1.75 !important; }
.hero-acceptance a { font-size: 13px !important; }

.course-layout { gap: 44px; }
.side-title { font-size: 12px !important; }
.module-nav a { font-size: 13px !important; line-height: 1.5; }
.toc a { font-size: 13px !important; line-height: 1.6; }

.lesson-section h2 { font-size: clamp(1.7rem, 3vw, 2.3rem) !important; }
.lesson-section h3 { font-size: 18px !important; }
.lesson-section h4 { font-size: 16px !important; }
.lesson-section p, .lesson-section li { font-size: 16px !important; line-height: 1.8 !important; }
.lesson-section p, .lesson-section ul, .lesson-section ol { max-width: 72ch; }
.lesson-section ul li { font-size: 16px !important; }
.lesson-section ol li { font-size: 16px !important; }
.lesson-section .data-table, .lesson-section .data-table p, .lesson-section .data-table li { font-size: 14px !important; }
.data-table th { font-size: 13px !important; background: #f3f0e9 !important; }
.data-table td { font-size: 14px !important; }
.data-table code { font-size: 13px !important; }

.callout {
  background: #f3f0e9 !important;
  color: var(--ink) !important;
  border-left: 3px solid var(--accent, var(--coral)) !important;
  font-size: 15px !important;
  line-height: 1.75 !important;
}
.callout strong { color: var(--accent, var(--coral)) !important; }
.callout.warn { background: #f7f2e5 !important; border-left-color: var(--yellow) !important; }

.code {
  background: #f3f0e9 !important;
  color: var(--ink) !important;
  border: 1px solid var(--line);
  font-size: 14px !important;
  line-height: 1.8 !important;
}
.code .c-comment { color: #665f6e !important; }
.code .c-key { color: #a3422e !important; }
.code .c-val { color: #236b43 !important; }

.acceptance {
  background: #fff !important;
  border: 1px solid var(--line) !important;
  border-left: 3px solid var(--accent, var(--coral)) !important;
  border-top: 1px solid var(--line) !important;
  box-shadow: none;
}
.acceptance h2 { font-size: 22px !important; }
.acceptance > p, .acceptance .deliverable { font-size: 16px !important; line-height: 1.8 !important; }
.acceptance .deliverable { background: #f7f5ef; }
.checklist-head { font-size: 12px !important; }
.checklist label { font-size: 15px !important; line-height: 1.7 !important; }
.checklist input { width: 16px; height: 16px; }

.step { font-size: 15px !important; line-height: 1.75 !important; }
.self-test summary { font-size: 15px !important; line-height: 1.7 !important; }
.self-test .answer { font-size: 15px !important; line-height: 1.8 !important; }

.module-row {
  border-left: 3px solid var(--accent, var(--coral));
  background: #fff;
}
.module-row.extra { border-style: dashed; }
.module-row:hover { transform: translateY(-2px); }
.module-num { font-size: 22px !important; }
.module-info h3 { font-size: 18px !important; }
.module-info p { font-size: 15px !important; line-height: 1.75 !important; }
.module-tag { font-size: 12px !important; }
.module-hours { display: block; margin-top: 6px; font-size: 13px !important; color: var(--soft) !important; }
.module-go { font-size: 13px !important; }

.hub-list-head p { font-size: 16px !important; line-height: 1.8 !important; }
.hub-side > span { font-size: 12px !important; }
.hub-side h2 { font-size: 18px !important; }
.hub-side ol, .hub-side li { font-size: 15px !important; line-height: 1.75 !important; }
.hub-stat strong { font-size: 26px !important; }
.hub-stat span { font-size: 13px !important; }

.pager-card span { font-size: 12px !important; }
.pager-card strong { font-size: 15px !important; }
.pager-card:hover { transform: translateY(-2px); }
.module-list { gap: 12px; }

.submodule {
  margin: 24px 0;
  padding: 22px;
  background: #fff;
  border: 1px solid var(--line);
  border-left: 3px solid var(--accent, var(--coral));
  border-radius: 16px;
}
.submodule-head {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  justify-content: space-between;
  gap: 10px;
  margin-bottom: 10px;
}
.submodule-head h3 { margin: 0; }
.submodule-head span { font-size: 13px !important; color: var(--soft); }
.submodule > p { font-size: 16px !important; line-height: 1.8 !important; max-width: 72ch; }
.lesson-plan { display: grid; gap: 0; margin: 14px 0 18px; padding: 0; list-style: none; }
.lesson-plan li {
  display: flex;
  gap: 10px;
  align-items: baseline;
  padding: 9px 0;
  border-bottom: 1px dashed var(--line);
  font-size: 15px !important;
  line-height: 1.7 !important;
}
.lesson-plan li:last-child { border-bottom: none; }
.lesson-plan b {
  flex: none;
  font-family: "SF Mono", "Menlo", ui-monospace, monospace;
  font-size: 12px !important;
  color: var(--accent, var(--coral));
}
.submodule-acceptance {
  margin-top: 16px;
  padding: 15px 16px;
  background: #f7f5ef;
  border-radius: 12px;
  font-size: 15px !important;
  line-height: 1.75 !important;
}
.submodule-acceptance strong { color: var(--accent, var(--coral)); }

footer { border-top: 1px solid var(--line); }
.footer-links, .footer-brand p, .footer-bottom { font-size: 13px !important; }
.footer-bottom { font-size: 12px !important; }

.career-section { padding: 0 0 76px; }
.career-head { max-width: 720px; margin-bottom: 26px; }
.career-head p { margin-top: 10px; font-size: 15px !important; line-height: 1.75 !important; color: var(--muted) !important; }
.career-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 18px; }
.career-card {
  padding: 24px;
  background: #fff;
  border: 1px solid var(--line);
  border-left: 3px solid var(--accent, var(--coral));
  border-radius: 18px;
}
.career-stage { display: block; margin-bottom: 8px; font-size: 12px !important; font-weight: 800; letter-spacing: 0.14em; color: var(--accent, var(--coral)); }
.career-card h3 { margin: 0 0 4px; font-size: 21px !important; }
.career-layer { margin-bottom: 0 !important; font-size: 13px !important; color: var(--soft) !important; }
.career-salary { display: inline-block; margin: 12px 0 10px; padding: 6px 10px; border-radius: 6px; background: #f3f0e9; color: var(--accent, var(--coral)); font-size: 15px !important; font-weight: 700; }
.career-card > p { margin: 8px 0; font-size: 15px !important; line-height: 1.75 !important; color: var(--muted) !important; }
.career-card ul { display: grid; gap: 6px; margin: 12px 0 16px; padding-left: 16px; font-size: 14px !important; line-height: 1.7 !important; color: var(--muted); }
.career-card li::marker { color: var(--accent, var(--coral)); }
.career-links { display: flex; flex-wrap: wrap; gap: 8px; padding-top: 14px; border-top: 1px dashed var(--line); }
.career-links a { font-size: 13px !important; font-weight: 700; color: var(--accent, var(--coral)); }
.career-links a:hover { text-decoration: underline; }

.final-challenge { padding: 0 0 86px; }
.final-card {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 28px;
  padding: 28px;
  background: #fff;
  border: 1px solid var(--line);
  border-left: 3px solid var(--yellow);
  border-radius: 20px;
  transition: transform 0.22s ease, box-shadow 0.22s ease;
}
.final-card:hover { transform: translateY(-2px); box-shadow: var(--shadow-md); }
.final-tag { display: block; margin-bottom: 8px; font-size: 12px !important; font-weight: 800; letter-spacing: 0.14em; color: var(--yellow); }
.final-card h2 { margin-bottom: 8px; }
.final-card p { max-width: 72ch; font-size: 15px !important; line-height: 1.75 !important; color: var(--muted) !important; }
.final-go { display: inline-flex; align-items: center; gap: 7px; flex: none; font-size: 14px !important; font-weight: 700; color: var(--yellow); }

.download-box h4 { margin: 0; font-size: 16px !important; color: var(--ink); }

@media (max-width: 960px) {
  .course-hero, .hub-hero { padding: 40px 0 38px; }
  .course-layout { gap: 28px; padding: 36px 0 66px; }
  .module-nav a { font-size: 13px !important; }
  .lesson-section p, .lesson-section li { font-size: 16px !important; }
  .career-grid { grid-template-columns: 1fr; }
}

@media (max-width: 640px) {
  .course-hero h1 { font-size: clamp(2.2rem, 8.5vw, 2.6rem) !important; }
  .course-hero p.lead { font-size: 16px !important; }
  .lesson-section h2 { font-size: clamp(1.7rem, 6vw, 2.3rem) !important; }
  .lesson-section p, .lesson-section li { font-size: 16px !important; }
  .acceptance { padding: 20px 17px; }
  .module-row { padding: 18px; }
  .module-info p { font-size: 15px !important; }
  .submodule { padding: 18px 16px; }
  .final-card { flex-direction: column; align-items: flex-start; padding: 22px; }
}