/* Exam study plans (scripts/build_study_plan.py). Course-neutral: the page
   sets --hue on <html>, chapter chips set their own --hue inline. */

:root {
  --bg: #f6f5fb;
  --surface: #ffffff;
  --surface-2: #f1eff8;
  --surface-3: #e9e6f3;
  --border: #e1ddec;
  --text: #17152b;
  --dim: #5d5974;
  --faint: #8b87a3;
  --good: hsl(152 60% 32%);
  --good-soft: hsl(152 60% 40% / 0.11);
  --skip: hsl(352 60% 46%);
  --skip-soft: hsl(352 80% 55% / 0.08);
  --lit: 48%;
  --shadow: 0 1px 2px rgba(30, 20, 70, 0.05), 0 8px 26px rgba(40, 25, 90, 0.06);
  --mono: "JetBrains Mono", ui-monospace, monospace;
  --serif: "Fraunces", Georgia, serif;
  --sans: "Inter", system-ui, -apple-system, "Segoe UI", sans-serif;
  --pad: clamp(12px, 3vw, 44px);
  color-scheme: light;
}

html[data-theme="dark"] {
  --bg: #090b14;
  --surface: #121627;
  --surface-2: #0f1322;
  --surface-3: #1a2036;
  --border: #252c47;
  --text: #eceffb;
  --dim: #a0a8c6;
  --faint: #6f789a;
  --good: hsl(152 58% 60%);
  --good-soft: hsl(152 55% 50% / 0.14);
  --skip: hsl(352 85% 72%);
  --skip-soft: hsl(352 80% 60% / 0.1);
  --lit: 68%;
  --shadow: 0 1px 2px rgba(0, 0, 0, 0.5), 0 12px 32px rgba(0, 0, 0, 0.4);
  color-scheme: dark;
}

html,
[style*="--hue"] {
  --accent: hsl(var(--hue, 262) 72% var(--lit));
  --accent-soft: hsl(var(--hue, 262) 85% var(--lit) / 0.11);
  --accent-line: hsl(var(--hue, 262) 70% var(--lit) / 0.38);
  --accent-fill: hsl(var(--hue, 262) 70% 42%);
}

/* html-theme-sync.js injects overflow-x:hidden, which breaks the sticky bar */
html:not(#sp),
html:not(#sp) body {
  overflow-x: clip;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
  scroll-padding-top: 76px;
}

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font: 15.5px/1.6 var(--sans);
  -webkit-font-smoothing: antialiased;
}

a {
  color: var(--accent);
}

.wrap {
  max-width: 1680px;
  margin: 0 auto;
  padding: 0 var(--pad);
}

/* ---------- top bar ---------- */
.topbar {
  position: sticky;
  top: 0;
  z-index: 30;
  background: color-mix(in srgb, var(--bg) 88%, transparent);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border);
}

.topbar .wrap {
  display: flex;
  align-items: center;
  gap: 8px 18px;
  min-height: 58px;
  flex-wrap: wrap;
  padding-top: 8px;
  padding-bottom: 8px;
}

.brand {
  font: 600 12.5px/1 var(--mono);
  letter-spacing: 0.06em;
  color: var(--dim);
  white-space: nowrap;
}

.brand b {
  color: var(--text);
}

.topnav {
  display: flex;
  gap: 4px;
  flex-wrap: wrap;
}

.topnav a {
  font-size: 13.5px;
  font-weight: 600;
  text-decoration: none;
  color: var(--dim);
  padding: 6px 12px;
  border-radius: 999px;
}

.topnav a:hover {
  color: var(--text);
  background: var(--surface-3);
}

.topbar-end {
  margin-left: auto;
  display: flex;
  align-items: center;
  gap: 8px;
}

.btn {
  font: 600 13px/1 var(--sans);
  color: var(--text);
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 999px;
  padding: 9px 14px;
  cursor: pointer;
}

.btn:hover {
  border-color: var(--accent-line);
}

.plan-cal {
  display: inline-flex;
  margin-top: 14px;
  text-decoration: none;
  border-color: var(--accent-line);
}

.btn:focus-visible,
.budget input:focus-visible + span,
.done input:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
}

/* ---------- hero ---------- */
.hero {
  padding: clamp(22px, 4vw, 52px) 0 6px;
}

.eyebrow {
  font: 600 12px/1.4 var(--mono);
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--accent);
}

h1 {
  font-family: var(--serif);
  font-weight: 650;
  font-size: clamp(30px, 4.6vw, 54px);
  line-height: 1.05;
  margin: 8px 0 12px;
  letter-spacing: -0.01em;
}

.lede {
  color: var(--dim);
  font-size: clamp(15px, 1.3vw, 17.5px);
  margin: 0;
}

.facts {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin: 16px 0 0;
  padding: 0;
  list-style: none;
}

.facts li {
  font-size: 13.5px;
  color: var(--dim);
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 999px;
  padding: 5px 12px;
}

.facts b {
  color: var(--text);
}

/* ---------- time budget ---------- */
.budget-panel {
  margin: 24px 0 0;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 16px;
  padding: 16px;
  box-shadow: var(--shadow);
}

.budget-panel legend {
  font: 600 12px/1 var(--mono);
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--dim);
  padding: 0;
  margin-bottom: 12px;
}

.budget {
  border: 0;
  margin: 0;
  padding: 0;
  min-width: 0;
}

.budget-options {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(min(100%, 200px), 1fr));
  gap: 8px;
}

.budget label {
  cursor: pointer;
}

.budget input {
  position: absolute;
  opacity: 0;
  pointer-events: none;
}

.budget label > span {
  display: block;
  height: 100%;
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 10px 14px;
  background: var(--surface-2);
}

.budget label b {
  display: block;
  font-weight: 650;
}

.budget label small {
  font: 500 12.5px/1.4 var(--mono);
  color: var(--dim);
}

.budget input:checked + span {
  border-color: var(--accent);
  background: var(--accent-soft);
  box-shadow: inset 0 0 0 1px var(--accent);
}

.progress {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-top: 14px;
  font-size: 14px;
  color: var(--dim);
}

.progress .track {
  flex: 1;
  height: 8px;
  border-radius: 999px;
  background: var(--surface-3);
  overflow: hidden;
}

.progress .fill {
  display: block;
  height: 100%;
  width: 0;
  background: var(--good);
  border-radius: inherit;
  transition: width 0.25s ease;
}

.progress b {
  color: var(--text);
}

/* ---------- sections ---------- */
.part {
  padding: 34px 0 6px;
}

.part > h2,
.tier-head h2 {
  font-family: var(--serif);
  font-weight: 650;
  font-size: clamp(22px, 2.4vw, 30px);
  line-height: 1.15;
  margin: 0;
}

.part > p {
  color: var(--dim);
  margin: 6px 0 16px;
}

.tier {
  margin: 0 0 26px;
}

.tier[hidden] {
  display: none;
}

.tier-head {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 4px 14px;
  margin: 0 0 12px;
}

.tier-head .tier-tag {
  font: 600 11.5px/1 var(--mono);
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: #fff;
  background: var(--accent-fill);
  border-radius: 999px;
  padding: 5px 10px;
}

.tier-head p {
  margin: 0;
  color: var(--dim);
  flex-basis: 100%;
}

.tier-head .tier-time {
  font: 600 13px/1 var(--mono);
  color: var(--dim);
}

/* ---------- plan items ---------- */
.items {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(min(100%, 440px), 1fr));
  gap: 12px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.item {
  display: grid;
  grid-template-columns: auto 1fr;
  gap: 4px 14px;
  background: var(--surface);
  border: 1px solid var(--border);
  border-left: 3px solid var(--accent);
  border-radius: 14px;
  padding: 14px 16px;
}

.item.is-done {
  border-left-color: var(--good);
  background: color-mix(in srgb, var(--surface) 80%, var(--good-soft));
}

.item .num {
  font: 700 13px/26px var(--mono);
  width: 26px;
  height: 26px;
  text-align: center;
  border-radius: 50%;
  background: var(--accent-soft);
  color: var(--accent);
}

.item.is-done .num {
  background: var(--good);
  color: var(--surface);
}

.item h3 {
  font-size: 16px;
  line-height: 1.35;
  margin: 1px 0 0;
}

.item h3 a {
  color: var(--text);
  text-decoration: none;
}

.item h3 a:hover {
  color: var(--accent);
  text-decoration: underline;
}

.item.is-done h3 a {
  color: var(--dim);
}

.item .body {
  grid-column: 2;
  min-width: 0;
}

.meta {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 6px;
  margin: 6px 0 8px;
}

.chip {
  font: 600 11.5px/1 var(--mono);
  padding: 4px 8px;
  border-radius: 999px;
  color: var(--accent);
  background: var(--accent-soft);
  border: 1px solid var(--accent-line);
  white-space: nowrap;
}

.mins {
  font: 600 12px/1 var(--mono);
  color: var(--dim);
  margin-left: auto;
  white-space: nowrap;
}

.focus,
.why {
  margin: 0;
  font-size: 14.5px;
}

.focus {
  color: var(--text);
}

.focus b,
.why b {
  font-weight: 650;
}

.why {
  color: var(--dim);
  margin-top: 4px;
}

.done {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  margin-top: 10px;
  font-size: 13.5px;
  font-weight: 600;
  color: var(--dim);
  cursor: pointer;
}

.done input {
  width: 17px;
  height: 17px;
  margin: 0;
  accent-color: var(--good);
  cursor: pointer;
}

/* ---------- skip ---------- */
.skips {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(min(100%, 380px), 1fr));
  gap: 12px;
}

.skip {
  background: var(--surface);
  border: 1px solid var(--border);
  border-left: 3px solid var(--skip);
  border-radius: 14px;
  padding: 14px 16px;
}

.skip h3 {
  font-size: 15.5px;
  line-height: 1.35;
  margin: 0 0 6px;
}

.skip h3 a {
  color: var(--text);
  text-decoration: none;
}

.skip h3 a:hover {
  text-decoration: underline;
}

.skip-tag {
  display: inline-block;
  font: 600 11px/1 var(--mono);
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--skip);
  background: var(--skip-soft);
  border-radius: 999px;
  padding: 4px 8px;
  margin-bottom: 8px;
}

.skip p {
  margin: 0;
  font-size: 14.5px;
  color: var(--dim);
}

.instead {
  display: inline-block;
  margin-top: 10px;
  font-size: 14px;
  font-weight: 600;
  text-decoration: none;
}

.instead:hover {
  text-decoration: underline;
}

/* ---------- later ---------- */
.later {
  background: var(--surface-2);
  border: 1px solid var(--border);
  border-radius: 14px;
  padding: 16px;
}

.later p {
  margin: 0 0 12px;
  color: var(--dim);
}

.later ul {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.later a {
  display: inline-block;
  font-size: 13.5px;
  font-weight: 600;
  text-decoration: none;
  color: var(--text);
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 999px;
  padding: 6px 12px;
}

.later a:hover {
  border-color: var(--accent-line);
}

.foot {
  color: var(--faint);
  font-size: 13px;
  margin: 34px 0 40px;
}

@media (max-width: 640px) {
  .topbar .wrap {
    gap: 6px 10px;
  }
  .topnav a {
    padding: 5px 9px;
    font-size: 13px;
  }
  .item,
  .skip {
    padding: 12px 13px;
  }
  .item {
    gap: 4px 10px;
  }
  .mins {
    margin-left: 0;
  }
}

@media print {
  .topbar,
  .budget-panel,
  .done {
    display: none;
  }
  .tier[hidden] {
    display: block;
  }
}