/* =============================================================================
   claude-howto landing — "Terminal Luxe" (dark) / "Ivory" (light)
   All colors flow through CSS custom properties: `:root` holds the light
   tokens, `html.dark` overrides them with the Terminal Luxe palette, and the
   no-JS media query mirrors `html.dark` (the inline script removes .no-js
   when JS runs, so a no-JS visitor on a dark OS still gets dark colors).
   Emerald #22C55E stays decorative in both themes — lines, borders, the
   subway track, the progress ring, checkmarks — never a background fill.
   Green *text* uses --green (#15803D in light for WCAG AA contrast).
   ============================================================================= */

:root {
  /* ---------- Dark palette constants ----------
     Referenced by both the html.dark block and the no-JS media query below,
     so the Terminal Luxe values live once here and both blocks stay in sync. */
  --d-bg: #141413;
  --d-panel: rgba(255, 255, 255, 0.03);
  --d-panel-2: rgba(255, 255, 255, 0.05);
  --d-line: rgba(255, 255, 255, 0.09);
  --d-line-soft: rgba(255, 255, 255, 0.06);
  --d-line-hover: rgba(255, 255, 255, 0.2);
  --d-line-strong: rgba(255, 255, 255, 0.3);
  --d-line-bright: rgba(255, 255, 255, 0.35);
  --d-node-ring: rgba(255, 255, 255, 0.28);
  --d-text: #fff;
  --d-text-dim: rgba(255, 255, 255, 0.7);
  --d-text-faint: rgba(255, 255, 255, 0.5);
  --d-green: #22c55e;
  --d-amber: #f59e0b;
  --d-blue: #3b82f6;
  --d-red: #ef4444;
  --d-grid: rgba(255, 255, 255, 0.028);
  --d-grain: 0.035;
  --d-nav: rgba(20, 20, 19, 0.75);
  --d-nav-menu: rgba(20, 20, 19, 0.95);
  --d-selection: #fff;
  --d-em-glow: 0 0 32px rgba(34, 197, 94, 0.35);
  --d-shadow-btn:
    0 0 28px var(--green-glow), inset 0 0 18px rgba(34, 197, 94, 0.06);
  --d-shadow-card:
    0 14px 40px rgba(0, 0, 0, 0.5), 0 0 30px rgba(34, 197, 94, 0.05);
  --d-shadow-done: 0 0 26px rgba(34, 197, 94, 0.06);
  --d-shadow-term:
    0 0 0 1px rgba(0, 0, 0, 0.6),
    0 24px 70px rgba(0, 0, 0, 0.65),
    0 0 60px rgba(34, 197, 94, 0.07);

  /* ---------- Semantic tokens — "Ivory" light defaults ----------
     Warm near-white canvas, black text, black-at-low-alpha borders, soft
     shadows for depth instead of glows. */
  --bg: #faf9f5;
  --panel: rgba(96, 78, 46, 0.045);
  --panel-2: rgba(96, 78, 46, 0.075);
  --line: rgba(0, 0, 0, 0.11);
  --line-soft: rgba(0, 0, 0, 0.07);
  --line-hover: rgba(0, 0, 0, 0.18);
  --line-strong: rgba(0, 0, 0, 0.26);
  --line-bright: rgba(0, 0, 0, 0.34);
  --node-ring: rgba(0, 0, 0, 0.26);
  --text: #101210;
  --text-dim: rgba(0, 0, 0, 0.68);
  --text-faint: rgba(0, 0, 0, 0.56);
  --green: #15803d;
  --amber: #b45309;
  --blue: #1d4ed8;
  --red: #dc2626;
  --grid: rgba(0, 0, 0, 0.038);
  --grain: 0.05;
  --nav: rgba(251, 250, 247, 0.8);
  --nav-menu: rgba(251, 250, 247, 0.96);
  --selection: #101210;
  --em-glow: 0 0 28px rgba(34, 197, 94, 0.16);
  --shadow-btn:
    0 0 24px rgba(34, 197, 94, 0.16), inset 0 0 18px rgba(34, 197, 94, 0.05);
  --shadow-card:
    0 14px 40px rgba(16, 20, 17, 0.1), 0 0 30px rgba(34, 197, 94, 0.05);
  --shadow-done:
    0 10px 32px rgba(16, 20, 17, 0.08), 0 0 26px rgba(34, 197, 94, 0.07);
  --shadow-term:
    0 0 0 1px rgba(0, 0, 0, 0.16),
    0 24px 60px rgba(16, 20, 17, 0.18),
    0 0 60px rgba(34, 197, 94, 0.09);

  /* ---------- Theme-independent emerald ----------
     #22C55E family for lines, borders, the subway track, the progress ring
     stroke and checkmarks — identical in both themes. */
  --green-vivid: #22c55e;
  --green-soft: rgba(34, 197, 94, 0.7);
  --green-line: rgba(34, 197, 94, 0.35);
  --green-glow: rgba(34, 197, 94, 0.22);
  --green-tint-03: rgba(34, 197, 94, 0.03);
  --green-tint-045: rgba(34, 197, 94, 0.045);
  --green-tint-05: rgba(34, 197, 94, 0.05);
  --green-tint-06: rgba(34, 197, 94, 0.06);
  --green-tint-18: rgba(34, 197, 94, 0.18);
  --green-tint-28: rgba(34, 197, 94, 0.28);
  --green-tint-45: rgba(34, 197, 94, 0.45);
  --green-tint-55: rgba(34, 197, 94, 0.55);
  --green-none: rgba(34, 197, 94, 0);
  --amber-line: rgba(245, 158, 11, 0.5);

  /* ---------- Dark "chip" surfaces ----------
     The hero terminal and the copy-code chips stay dark in both themes;
     their internals read only these tokens so they never flip. */
  --chip-bg: #030604;
  --chip-panel: rgba(255, 255, 255, 0.05);
  --chip-line: rgba(255, 255, 255, 0.09);
  --chip-line-soft: rgba(255, 255, 255, 0.06);
  --chip-text: #fff;
  --chip-dim: rgba(255, 255, 255, 0.7);
  --chip-faint: rgba(255, 255, 255, 0.5);
  --chip-green: #22c55e;
  --chip-blue: #3b82f6;
  --chip-amber: #f59e0b;

  --font-display: "Fraunces", "Iowan Old Style", Georgia, serif;
  --font-body: "Manrope", system-ui, -apple-system, "Segoe UI", sans-serif;
  --font-mono: "JetBrains Mono", ui-monospace, "SF Mono", Menlo, monospace;
  --wrap: 72rem;
  --ease-out: cubic-bezier(0.16, 1, 0.3, 1);
  color-scheme: light;
}

/* ---------- Terminal Luxe dark tokens ---------- */

html.dark {
  --bg: var(--d-bg);
  --panel: var(--d-panel);
  --panel-2: var(--d-panel-2);
  --line: var(--d-line);
  --line-soft: var(--d-line-soft);
  --line-hover: var(--d-line-hover);
  --line-strong: var(--d-line-strong);
  --line-bright: var(--d-line-bright);
  --node-ring: var(--d-node-ring);
  --text: var(--d-text);
  --text-dim: var(--d-text-dim);
  --text-faint: var(--d-text-faint);
  --green: var(--d-green);
  --amber: var(--d-amber);
  --blue: var(--d-blue);
  --red: var(--d-red);
  --grid: var(--d-grid);
  --grain: var(--d-grain);
  --nav: var(--d-nav);
  --nav-menu: var(--d-nav-menu);
  --selection: var(--d-selection);
  --em-glow: var(--d-em-glow);
  --shadow-btn: var(--d-shadow-btn);
  --shadow-card: var(--d-shadow-card);
  --shadow-done: var(--d-shadow-done);
  --shadow-term: var(--d-shadow-term);
  color-scheme: dark;
}

/* No-JS: no inline script ran, so follow the OS scheme directly.
   Keep this block identical to html.dark above. */
@media (prefers-color-scheme: dark) {
  html.no-js {
    --bg: var(--d-bg);
    --panel: var(--d-panel);
    --panel-2: var(--d-panel-2);
    --line: var(--d-line);
    --line-soft: var(--d-line-soft);
    --line-hover: var(--d-line-hover);
    --line-strong: var(--d-line-strong);
    --line-bright: var(--d-line-bright);
    --node-ring: var(--d-node-ring);
    --text: var(--d-text);
    --text-dim: var(--d-text-dim);
    --text-faint: var(--d-text-faint);
    --green: var(--d-green);
    --amber: var(--d-amber);
    --blue: var(--d-blue);
    --red: var(--d-red);
    --grid: var(--d-grid);
    --grain: var(--d-grain);
    --nav: var(--d-nav);
    --nav-menu: var(--d-nav-menu);
    --selection: var(--d-selection);
    --em-glow: var(--d-em-glow);
    --shadow-btn: var(--d-shadow-btn);
    --shadow-card: var(--d-shadow-card);
    --shadow-done: var(--d-shadow-done);
    --shadow-term: var(--d-shadow-term);
    color-scheme: dark;
  }
}

/* ---------- Reset ---------- */

*,
*::before,
*::after {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
  scroll-padding-top: 5.5rem;
}

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: var(--font-body);
  font-size: 1rem;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

/* Faint blueprint grid over the whole page */
body::before {
  content: "";
  position: fixed;
  inset: 0;
  z-index: 0;
  pointer-events: none;
  background-image:
    linear-gradient(var(--grid) 1px, transparent 1px),
    linear-gradient(90deg, var(--grid) 1px, transparent 1px);
  background-size: 72px 72px;
  mask-image: radial-gradient(ellipse 120% 90% at 50% 0%, #000 30%, transparent 78%);
  -webkit-mask-image: radial-gradient(ellipse 120% 90% at 50% 0%, #000 30%, transparent 78%);
}

/* Film grain */
body::after {
  content: "";
  position: fixed;
  inset: -50%;
  z-index: 90;
  pointer-events: none;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='160' height='160'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.9' numOctaves='2' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='160' height='160' filter='url(%23n)' opacity='0.5'/%3E%3C/svg%3E");
  opacity: var(--grain);
}

main,
.nav,
.footer {
  position: relative;
  z-index: 1;
}

img {
  max-width: 100%;
}

a {
  color: var(--green);
  text-decoration: none;
}

a:hover {
  text-decoration: underline;
  text-underline-offset: 3px;
}

code {
  font-family: var(--font-mono);
  font-size: 0.875em;
  color: var(--green);
  border: 1px solid var(--green-line);
  border-radius: 5px;
  padding: 0.08em 0.4em;
  white-space: nowrap;
}

:focus-visible {
  outline: 2px solid var(--green-vivid);
  outline-offset: 3px;
  border-radius: 4px;
}

::selection {
  background: var(--green-tint-28);
  color: var(--selection);
}

.skip-link {
  position: absolute;
  left: 1rem;
  top: -3rem;
  z-index: 200;
  padding: 0.5rem 1rem;
  border: 1px solid var(--green-vivid);
  border-radius: 8px;
  background: var(--bg);
  color: var(--green);
  font-family: var(--font-mono);
  font-size: 0.8rem;
  transition: top 0.2s;
}

.skip-link:focus {
  top: 0.75rem;
}

.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

/* ---------- Buttons ---------- */

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  padding: 0.8rem 1.6rem;
  border-radius: 10px;
  border: 1px solid transparent;
  font-family: var(--font-body);
  font-size: 0.95rem;
  font-weight: 600;
  letter-spacing: 0.01em;
  cursor: pointer;
  transition:
    border-color 0.25s var(--ease-out),
    box-shadow 0.25s var(--ease-out),
    color 0.25s var(--ease-out),
    translate 0.25s var(--ease-out),
    background-color 0.25s var(--ease-out);
}

#continue-btn[hidden] {
  display: none;
}

.btn:hover {
  text-decoration: none;
  translate: 0 -1px;
}

.btn-primary {
  color: var(--green);
  border-color: var(--green-soft);
  background: transparent;
}

.btn-primary:hover {
  color: var(--green);
  border-color: var(--green-vivid);
  box-shadow: var(--shadow-btn);
}

.btn-ghost {
  color: var(--text);
  border-color: var(--line);
  background: transparent;
}

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

.btn-sm {
  padding: 0.5rem 1.05rem;
  font-size: 0.85rem;
  border-radius: 8px;
}

/* ---------- Nav ---------- */

.nav {
  position: sticky;
  top: 0;
  z-index: 80;
  border-bottom: 1px solid var(--line-soft);
  background: var(--nav);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
}

.nav-inner {
  max-width: var(--wrap);
  margin: 0 auto;
  display: flex;
  align-items: center;
  gap: 1.25rem;
  padding: 0.85rem 1.5rem;
}

.nav-brand {
  display: inline-flex;
  align-items: center;
  gap: 0.6rem;
  color: var(--text);
}

.nav-brand:hover {
  text-decoration: none;
}

.nav-logo {
  height: 30px;
  width: auto;
}

/* Logo swap: light wordmark on the Ivory theme, dark wordmark on
   Terminal Luxe. The no-JS media query mirrors html.dark. */
.logo-dark {
  display: none;
}

html.dark .logo-light {
  display: none;
}

html.dark .logo-dark {
  display: inline;
}

@media (prefers-color-scheme: dark) {
  html.no-js .logo-light {
    display: none;
  }

  html.no-js .logo-dark {
    display: inline;
  }
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 1.6rem;
  margin-left: auto;
}

.nav-links a {
  color: var(--text-dim);
  font-size: 0.88rem;
  font-weight: 500;
  transition: color 0.2s;
}

.nav-links a:hover {
  color: var(--text);
  text-decoration: none;
}

.nav-actions {
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

.nav-links + .nav-actions {
  margin-left: 0;
}

.nav-toggle {
  display: none;
  align-items: center;
  justify-content: center;
  width: 40px;
  height: 40px;
  border: 1px solid var(--line);
  border-radius: 9px;
  background: transparent;
  color: var(--text-dim);
  cursor: pointer;
}

.nav-toggle svg {
  width: 18px;
  height: 18px;
}

.nav-toggle .menu-close {
  display: none;
}

.nav-toggle[aria-expanded="true"] .menu-open {
  display: none;
}

.nav-toggle[aria-expanded="true"] .menu-close {
  display: block;
}

/* ---------- Theme toggle ---------- */

.theme-toggle {
  position: relative;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 40px;
  height: 40px;
  flex: none;
  border: 1px solid var(--line);
  border-radius: 9px;
  background: transparent;
  color: var(--text-dim);
  cursor: pointer;
  transition:
    color 0.2s,
    border-color 0.2s;
}

.theme-toggle:hover {
  color: var(--text);
  border-color: var(--line-strong);
}

.no-js .theme-toggle {
  display: none;
}

.theme-toggle svg {
  position: absolute;
  left: 50%;
  top: 50%;
  width: 18px;
  height: 18px;
  translate: -50% -50%;
  transition:
    opacity 0.25s var(--ease-out),
    rotate 0.3s var(--ease-out);
}

.theme-toggle .ti-sun {
  opacity: 0;
  rotate: -80deg;
}

html.dark .theme-toggle .ti-sun {
  opacity: 1;
  rotate: 0deg;
}

html.dark .theme-toggle .ti-moon {
  opacity: 0;
  rotate: 80deg;
}

/* Cross-fade colors for ~200ms while the theme flips. The class is added
   by JS on toggle only — never on first paint. */
html.theme-anim body,
html.theme-anim body * {
  transition:
    background-color 0.2s ease,
    color 0.2s ease,
    border-color 0.2s ease,
    box-shadow 0.2s ease !important;
}

/* ---------- Hero ---------- */

.hero {
  max-width: var(--wrap);
  margin: 0 auto;
  padding: 5.5rem 1.5rem 4rem;
}

.hero-grid {
  display: grid;
  grid-template-columns: minmax(0, 1.05fr) minmax(0, 0.95fr);
  gap: 3.5rem;
  align-items: center;
}

.eyebrow {
  margin: 0 0 1.4rem;
  font-family: var(--font-mono);
  font-size: 0.78rem;
  color: var(--green);
  letter-spacing: 0.06em;
}

.eyebrow-row {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 0.4rem 0.85rem;
  margin-bottom: 1.4rem;
}

.eyebrow-row .eyebrow {
  margin-bottom: 0;
}

.version-pill {
  font-family: var(--font-mono);
  font-size: 0.66rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--green);
  border: 1px solid var(--green-line);
  border-radius: 999px;
  padding: 0.24rem 0.7rem;
  white-space: nowrap;
}

.hero-title {
  margin: 0 0 1.4rem;
  font-family: var(--font-display);
  font-size: clamp(2.6rem, 5.6vw, 4.3rem);
  font-weight: 480;
  line-height: 1.04;
  letter-spacing: -0.015em;
  font-variation-settings: "opsz" 144;
}

.hero-title em {
  font-style: italic;
  color: var(--green);
  text-shadow: var(--em-glow);
}

.hero-sub {
  margin: 0 0 2rem;
  max-width: 34rem;
  font-size: 1.08rem;
  line-height: 1.7;
  color: var(--text-dim);
}

.hero-cta {
  display: flex;
  flex-wrap: wrap;
  gap: 0.9rem;
  margin-bottom: 2.6rem;
}

.hero-stats {
  display: flex;
  flex-wrap: wrap;
  gap: 0;
  margin: 0;
  padding: 0;
  border-top: 1px solid var(--line-soft);
}

.stat {
  padding: 1rem 1.8rem 0 0;
  margin-right: 1.8rem;
  border-right: 1px solid var(--line-soft);
}

.stat:last-child {
  border-right: 0;
  margin-right: 0;
  padding-right: 0;
}

.stat dt {
  font-family: var(--font-mono);
  font-size: 0.68rem;
  text-transform: uppercase;
  letter-spacing: 0.14em;
  color: var(--text-faint);
  margin-bottom: 0.25rem;
}

.stat dd {
  margin: 0;
  font-family: var(--font-display);
  font-size: 1.45rem;
  font-weight: 500;
  line-height: 1.2;
  white-space: nowrap;
}

/* ---------- Terminal ---------- */

.term {
  border: 1px solid var(--green-line);
  border-radius: 14px;
  background:
    linear-gradient(180deg, var(--green-tint-045), var(--green-none) 34%),
    var(--chip-bg);
  box-shadow: var(--shadow-term);
  overflow: hidden;
}

.term-bar {
  display: flex;
  align-items: center;
  gap: 7px;
  padding: 0.7rem 1rem;
  border-bottom: 1px solid var(--chip-line-soft);
}

.term-dot {
  width: 10px;
  height: 10px;
  border-radius: 50%;
  border: 1px solid var(--chip-line);
  background: var(--chip-panel);
}

.term-title {
  margin-left: auto;
  font-family: var(--font-mono);
  font-size: 0.7rem;
  color: var(--chip-faint);
  letter-spacing: 0.04em;
}

.term-body {
  padding: 1.1rem 1.25rem 1.35rem;
  font-family: var(--font-mono);
  font-size: 0.82rem;
  line-height: 1.85;
  min-height: 17.5rem;
}

.t-line {
  display: flex;
  gap: 0.55rem;
  white-space: pre-wrap;
  word-break: break-word;
  min-height: 1.5em;
}

.t-pp {
  color: var(--chip-green);
  flex: none;
}

.t-pp-in {
  color: var(--chip-blue);
}

.t-tt {
  color: var(--chip-text);
}

.t-tt.t-typing::after,
.t-line.t-caret .t-tt::after {
  content: "▌";
  margin-left: 1px;
  color: var(--chip-green);
  animation: caret-blink 1.05s steps(1) infinite;
}

.t-line.t-caret .t-tt:empty::after {
  margin-left: 0.15rem;
}

@keyframes caret-blink {
  0%, 55% { opacity: 1; }
  56%, 100% { opacity: 0; }
}

.t-line[data-c="dim"] { color: var(--chip-faint); }
.t-line[data-c="ok"] { color: var(--chip-green); }
.t-line[data-c="info"] { color: var(--chip-blue); }
.t-line[data-c="warn"] { color: var(--chip-amber); }

/* ---------- Sections ---------- */

.section {
  max-width: var(--wrap);
  margin: 0 auto;
  padding: 5rem 1.5rem 3rem;
}

.kicker {
  margin: 0 0 0.9rem;
  font-family: var(--font-mono);
  font-size: 0.75rem;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--green);
}

.kicker::before {
  content: "▸ ";
}

.section-title {
  margin: 0 0 1.1rem;
  font-family: var(--font-display);
  font-size: clamp(1.9rem, 3.6vw, 2.9rem);
  font-weight: 480;
  line-height: 1.12;
  letter-spacing: -0.01em;
}

.section-title em {
  font-style: italic;
  color: var(--green);
}

.section-sub {
  margin: 0 0 2.5rem;
  max-width: 40rem;
  color: var(--text-dim);
  font-size: 1.02rem;
}

/* ---------- Why cards ---------- */

.cards {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 1rem;
}

.card {
  min-width: 0;
  padding: 1.6rem 1.4rem 1.5rem;
  border: 1px solid var(--line);
  border-radius: 14px;
  background: var(--panel);
  transition:
    border-color 0.3s var(--ease-out),
    translate 0.3s var(--ease-out),
    box-shadow 0.3s var(--ease-out);
}

.card:hover {
  border-color: var(--green-line);
  translate: 0 -3px;
  box-shadow: var(--shadow-card);
}

.card-glyph {
  display: inline-flex;
  padding: 0.55rem;
  border: 1px solid var(--green-line);
  border-radius: 10px;
  color: var(--green);
  margin-bottom: 1.1rem;
}

.card-glyph svg {
  width: 20px;
  height: 20px;
}

.card h3 {
  margin: 0 0 0.55rem;
  font-family: var(--font-display);
  font-size: 1.15rem;
  font-weight: 560;
  letter-spacing: -0.01em;
}

.card p {
  margin: 0;
  font-size: 0.9rem;
  line-height: 1.65;
  color: var(--text-dim);
}

/* ---------- Versus ---------- */

.versus {
  border: 1px solid var(--line);
  border-radius: 14px;
  background: var(--panel);
  overflow: hidden;
}

.versus-head,
.versus-row {
  display: grid;
  grid-template-columns: minmax(7rem, 0.55fr) minmax(0, 1fr) minmax(0, 1.2fr);
  gap: 1.25rem;
  padding: 0.95rem 1.5rem;
  align-items: baseline;
}

.versus-head {
  border-bottom: 1px solid var(--line);
  font-family: var(--font-mono);
  font-size: 0.7rem;
  text-transform: uppercase;
  letter-spacing: 0.14em;
}

.versus-head .v-docs {
  color: var(--text-faint);
}

.versus-head .v-guide {
  color: var(--green);
}

.versus-row {
  border-bottom: 1px solid var(--line-soft);
  font-size: 0.92rem;
}

.versus-row:last-child {
  border-bottom: 0;
}

.v-label {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: var(--text-faint);
  letter-spacing: 0.04em;
}

.v-docs {
  color: var(--text-faint);
}

.v-guide {
  color: var(--text);
  position: relative;
  padding-left: 0.9rem;
}

.v-guide::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.3em;
  bottom: 0.3em;
  width: 2px;
  border-radius: 2px;
  background: var(--green-vivid);
  box-shadow: 0 0 12px var(--green-glow);
}

/* ---------- Progress panel ---------- */

.progress-panel {
  display: flex;
  align-items: center;
  gap: 2rem;
  margin: 0 0 3.5rem;
  padding: 1.5rem 1.75rem;
  border: 1px solid var(--line);
  border-radius: 16px;
  background: var(--panel);
}

.no-js .progress-panel {
  display: none;
}

.ring-wrap {
  position: relative;
  width: 104px;
  height: 104px;
  flex: none;
}

.ring {
  width: 104px;
  height: 104px;
  transform: rotate(-90deg);
}

.ring circle {
  fill: none;
  stroke-width: 7;
}

.ring-bg {
  stroke: var(--line);
}

.ring-fg {
  stroke: var(--green-vivid);
  stroke-linecap: round;
  stroke-dasharray: 326.7;
  stroke-dashoffset: 326.7;
  filter: drop-shadow(0 0 6px var(--green-tint-45));
  transition: stroke-dashoffset 0.7s var(--ease-out);
}

.ring-label {
  position: absolute;
  inset: 0;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 0;
}

.ring-pct {
  font-family: var(--font-display);
  font-size: 1.55rem;
  font-weight: 560;
  line-height: 1;
}

.ring-cap {
  font-family: var(--font-mono);
  font-size: 0.58rem;
  text-transform: uppercase;
  letter-spacing: 0.12em;
  color: var(--text-faint);
  margin-top: 0.2rem;
}

.progress-mid {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 1rem 2rem;
  min-width: 0;
}

.counts {
  margin: 0;
  font-size: 0.95rem;
  color: var(--text-dim);
  flex: 1 1 auto;
}

.counts b {
  color: var(--text);
  font-weight: 700;
  font-family: var(--font-mono);
}

.counts-sep {
  margin: 0 0.6rem;
  color: var(--text-faint);
}

.progress-actions {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.75rem;
}

#continue-btn {
  max-width: 100%;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.all-done {
  color: var(--green);
  font-family: var(--font-mono);
  font-size: 0.85rem;
}

/* ---------- Subway ---------- */

.subway {
  position: relative;
}

.track {
  position: absolute;
  left: 15px;
  top: 0;
  bottom: 0;
  width: 2px;
  background: var(--line-soft);
  border-radius: 2px;
}

.track-fill {
  width: 100%;
  height: 0;
  border-radius: 2px;
  background: linear-gradient(180deg, var(--green-vivid), var(--green-tint-55));
  box-shadow: 0 0 14px var(--green-glow);
  transition: height 0.2s linear;
}

.level {
  position: relative;
  margin-bottom: 3rem;
}

.level:last-child {
  margin-bottom: 0;
}

.level-head {
  padding-left: 3.4rem;
  margin-bottom: 1.4rem;
}

.level-name {
  margin: 0 0 0.35rem;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--green);
}

.level-title {
  margin: 0 0 0.4rem;
  font-family: var(--font-display);
  font-size: 1.6rem;
  font-weight: 520;
  letter-spacing: -0.01em;
}

.level-sum {
  margin: 0;
  max-width: 36rem;
  color: var(--text-dim);
  font-size: 0.94rem;
}

.stations {
  list-style: none;
  margin: 0;
  padding: 0;
}

.station {
  position: relative;
  padding-left: 3.4rem;
  margin-bottom: 1.1rem;
}

.node {
  position: absolute;
  left: 9px;
  top: 2.05rem;
  width: 14px;
  height: 14px;
  border-radius: 50%;
  border: 2px solid var(--node-ring);
  background: var(--bg);
  transition:
    border-color 0.35s var(--ease-out),
    box-shadow 0.35s var(--ease-out);
}

.station[data-status="in-progress"] .node,
.station[data-status="done"] .node {
  border-color: var(--green-vivid);
  box-shadow: 0 0 14px var(--green-glow);
}

.station[data-status="done"] .node::after {
  content: "";
  position: absolute;
  inset: 3px;
  border-radius: 50%;
  background: var(--green-vivid);
  box-shadow: 0 0 8px var(--green-glow);
}

.station-card {
  border: 1px solid var(--line);
  border-radius: 14px;
  background: var(--panel);
  padding: 1.3rem 1.5rem 1.1rem;
  transition:
    border-color 0.3s var(--ease-out),
    box-shadow 0.3s var(--ease-out);
}

.station-card:hover {
  border-color: var(--line-hover);
}

.station[data-status="in-progress"] .station-card {
  border-color: var(--green-line);
}

.station[data-status="done"] .station-card {
  border-color: var(--green-line);
  box-shadow: var(--shadow-done);
}

.station-head {
  display: flex;
  align-items: flex-start;
  gap: 1.1rem;
}

.station-num {
  font-family: var(--font-display);
  font-size: 1.9rem;
  font-weight: 300;
  font-style: italic;
  line-height: 1;
  color: var(--text-faint);
  flex: none;
  min-width: 2.2rem;
  padding-top: 0.15rem;
}

.station[data-status="done"] .station-num,
.station[data-status="in-progress"] .station-num {
  color: var(--green);
}

.station-meta {
  flex: 1;
  min-width: 0;
}

.station-title {
  margin: 0 0 0.3rem;
  font-family: var(--font-display);
  font-size: 1.25rem;
  font-weight: 560;
  letter-spacing: -0.01em;
}

.station-title a {
  color: var(--text);
  transition: color 0.2s;
}

.station-title a:hover {
  color: var(--green);
  text-decoration: none;
}

.station-tag {
  margin: 0;
  font-size: 0.88rem;
  color: var(--text-dim);
}

.station-side {
  display: flex;
  flex-direction: column;
  align-items: flex-end;
  gap: 0.5rem;
  flex: none;
}

.station-time {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  color: var(--text-faint);
  letter-spacing: 0.05em;
}

.pill {
  display: inline-flex;
  align-items: center;
  padding: 0.18rem 0.65rem;
  border-radius: 999px;
  border: 1px solid var(--line);
  font-family: var(--font-mono);
  font-size: 0.66rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--text-faint);
  white-space: nowrap;
}

.station[data-status="in-progress"] .pill {
  color: var(--amber);
  border-color: var(--amber-line);
}

.station[data-status="done"] .pill {
  color: var(--green);
  border-color: var(--green-soft);
}

.station-bar {
  display: flex;
  align-items: center;
  gap: 0.9rem;
  margin-top: 1rem;
}

.bar {
  flex: 1;
  height: 3px;
  border-radius: 3px;
  background: var(--line-soft);
  overflow: hidden;
}

.bar i {
  display: block;
  height: 100%;
  width: 0;
  border-radius: 3px;
  background: var(--green-vivid);
  box-shadow: 0 0 8px var(--green-glow);
  transition: width 0.5s var(--ease-out);
}

.bar-count {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  color: var(--text-faint);
  flex: none;
}

.station-toggle {
  display: inline-flex;
  align-items: center;
  gap: 0.45rem;
  margin-top: 0.9rem;
  padding: 0.35rem 0.7rem;
  border: 1px solid var(--line);
  border-radius: 7px;
  background: transparent;
  color: var(--text-dim);
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.05em;
  cursor: pointer;
  transition: color 0.2s, border-color 0.2s;
}

.no-js .station-toggle {
  display: none;
}

.station-toggle:hover {
  color: var(--text);
  border-color: var(--line-strong);
}

.station-toggle svg {
  width: 12px;
  height: 12px;
  transition: rotate 0.3s var(--ease-out);
}

.station-toggle[aria-expanded="true"] svg {
  rotate: 180deg;
}

.lessons {
  list-style: none;
  margin: 0.9rem 0 0;
  padding: 0.9rem 0 0;
  border-top: 1px solid var(--line-soft);
}

.lessons[hidden] {
  display: none;
}

.lesson {
  display: flex;
  align-items: center;
  gap: 0.3rem;
  padding: 0.42rem 0;
  font-size: 0.9rem;
}

.check {
  position: relative;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 44px;
  height: 44px;
  flex: none;
  border: 0;
  background: transparent;
  color: var(--green-vivid);
  cursor: pointer;
  padding: 0;
}

.check::before {
  content: "";
  position: absolute;
  width: 19px;
  height: 19px;
  border: 1px solid var(--line-strong);
  border-radius: 5px;
  transition: border-color 0.25s, box-shadow 0.25s;
}

.no-js .check {
  display: none;
}

.check svg {
  width: 13px;
  height: 13px;
}

.check-mark,
.check-dash {
  stroke-dasharray: 20;
  stroke-dashoffset: 20;
  transition: stroke-dashoffset 0.35s var(--ease-out);
}

.check[aria-checked="true"]::before {
  border-color: var(--green-vivid);
  box-shadow: 0 0 10px var(--green-tint-18);
}

.check[aria-checked="true"] .check-mark {
  stroke-dashoffset: 0;
}

.check[aria-checked="mixed"] {
  color: var(--amber);
}

.check[aria-checked="mixed"]::before {
  border-color: var(--amber);
}

.check[aria-checked="mixed"] .check-dash {
  stroke-dashoffset: 0;
}

.check:hover::before {
  border-color: var(--green-vivid);
}

.lesson-link {
  color: var(--text-dim);
  flex: 1;
  min-width: 0;
  transition: color 0.2s;
}

.lesson-link:hover {
  color: var(--text);
  text-decoration: none;
}

.lesson[data-status="done"] .lesson-link {
  color: var(--text-faint);
  text-decoration: line-through;
  text-decoration-color: var(--green-soft);
  text-decoration-thickness: 1px;
}

.lesson-status {
  flex: none;
  font-family: var(--font-mono);
  font-size: 0.65rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--text-faint);
}

.lesson[data-status="in-progress"] .lesson-status {
  color: var(--amber);
}

.lesson[data-status="done"] .lesson-status {
  color: var(--green);
}

/* ---------- Steps ---------- */

.steps {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 1rem;
  counter-reset: step;
}

.step {
  position: relative;
  min-width: 0;
  padding: 1.6rem 1.4rem;
  border: 1px solid var(--line);
  border-radius: 14px;
  background: var(--panel);
  transition: border-color 0.3s var(--ease-out), translate 0.3s var(--ease-out);
}

.step:hover {
  border-color: var(--green-line);
  translate: 0 -3px;
}

.step-num {
  font-family: var(--font-display);
  font-style: italic;
  font-weight: 300;
  font-size: 2rem;
  color: var(--green);
  line-height: 1;
  display: block;
  margin-bottom: 0.9rem;
}

.step h3 {
  margin: 0 0 0.5rem;
  font-family: var(--font-display);
  font-size: 1.15rem;
  font-weight: 560;
}

.step p {
  margin: 0 0 1.1rem;
  font-size: 0.88rem;
  color: var(--text-dim);
}

.code {
  display: flex;
  align-items: center;
  gap: 0.6rem;
  padding: 0.55rem 0.65rem 0.55rem 0.85rem;
  border: 1px solid var(--chip-line);
  border-radius: 9px;
  background: var(--chip-bg);
  overflow: hidden;
}

.code code {
  flex: 1;
  min-width: 0;
  border: 0;
  padding: 0;
  font-size: 0.74rem;
  color: var(--chip-text);
  overflow-x: auto;
  white-space: nowrap;
  scrollbar-width: none;
}

.code code::-webkit-scrollbar {
  display: none;
}

.copy {
  display: inline-flex;
  align-items: center;
  gap: 0.3rem;
  flex: none;
  border: 1px solid var(--chip-line);
  border-radius: 6px;
  background: transparent;
  color: var(--chip-dim);
  font-family: var(--font-mono);
  font-size: 0.62rem;
  letter-spacing: 0.06em;
  padding: 0.3rem 0.5rem;
  cursor: pointer;
  transition: color 0.2s, border-color 0.2s;
}

.copy svg {
  width: 12px;
  height: 12px;
}

.copy:hover {
  color: var(--chip-green);
  border-color: var(--green-soft);
}

.copy.copied {
  color: var(--chip-green);
  border-color: var(--green-vivid);
}

.step-link {
  font-family: var(--font-mono);
  font-size: 0.82rem;
  color: var(--green);
}

/* ---------- Footer ---------- */

.footer {
  margin-top: 4rem;
  border-top: 1px solid var(--line-soft);
  background: linear-gradient(180deg, var(--green-tint-03), transparent 40%);
}

.footer-inner {
  max-width: var(--wrap);
  margin: 0 auto;
  padding: 3rem 1.5rem 2rem;
  display: grid;
  grid-template-columns: 1.4fr 1fr 1fr 1fr;
  gap: 2rem;
}

.footer-logo {
  height: 36px;
  width: auto;
  margin-bottom: 0.9rem;
}

.footer-note {
  margin: 0;
  max-width: 18rem;
  font-size: 0.84rem;
  color: var(--text-faint);
}

.footer-head {
  margin: 0 0 0.9rem;
  font-family: var(--font-mono);
  font-size: 0.68rem;
  text-transform: uppercase;
  letter-spacing: 0.16em;
  color: var(--text-faint);
}

.footer-col a {
  display: block;
  margin-bottom: 0.5rem;
  font-size: 0.88rem;
  color: var(--text-dim);
}

.footer-col a:hover {
  color: var(--green);
}

.footer-version {
  display: block;
  margin-top: 0.9rem;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  color: var(--green);
}

.footer-base {
  max-width: var(--wrap);
  margin: 0 auto;
  padding: 1.2rem 1.5rem 1.6rem;
  border-top: 1px solid var(--line-soft);
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 1rem;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  color: var(--text-faint);
}

.footer-top:hover {
  text-decoration: none;
}

/* ---------- Reveal ---------- */

.js .reveal {
  opacity: 0;
  translate: 0 18px;
  transition:
    opacity 0.8s var(--ease-out) var(--d, 0s),
    translate 0.8s var(--ease-out) var(--d, 0s);
}

.js .reveal.in {
  opacity: 1;
  translate: 0 0;
}

/* ---------- Responsive ---------- */

@media (max-width: 62rem) {
  .hero-grid {
    grid-template-columns: 1fr;
    gap: 2.6rem;
  }

  .term-body {
    min-height: 0;
  }

  .cards {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .footer-inner {
    grid-template-columns: 1fr 1fr;
  }
}

@media (max-width: 56rem) {
  .nav:not(.nav-enhanced) .nav-inner {
    flex-wrap: wrap;
  }

  .nav-links {
    order: 3;
    width: 100%;
    margin-left: 0;
    flex-wrap: wrap;
    gap: 0.25rem 1rem;
  }

  .nav-enhanced .nav-links {
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    display: none;
    width: auto;
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    padding: 0.4rem 1rem 1rem;
    border-bottom: 1px solid var(--line-soft);
    background: var(--nav-menu);
    backdrop-filter: blur(14px);
    -webkit-backdrop-filter: blur(14px);
  }

  .nav-enhanced .nav-links.open {
    display: flex;
  }

  .nav-enhanced .nav-links a {
    padding: 0.7rem 0.5rem;
    font-size: 0.95rem;
    border-bottom: 1px solid var(--line-soft);
  }

  .nav-enhanced .nav-links a:last-child {
    border-bottom: 0;
  }

  .nav-enhanced .nav-toggle {
    display: inline-flex;
  }

  .nav-links + .nav-actions {
    margin-left: auto;
  }

  .versus-head,
  .versus-row {
    grid-template-columns: 1fr;
    gap: 0.3rem;
    padding: 0.9rem 1.2rem;
  }

  .versus-head {
    display: none;
  }

  .versus-row .v-docs::before {
    content: "Docs · ";
    font-family: var(--font-mono);
    font-size: 0.68rem;
    text-transform: uppercase;
    letter-spacing: 0.1em;
    color: var(--text-faint);
  }

  .versus-row .v-guide::before {
    content: "Guide · ";
    position: static;
    width: auto;
    background: none;
    box-shadow: none;
    font-family: var(--font-mono);
    font-size: 0.68rem;
    text-transform: uppercase;
    letter-spacing: 0.1em;
    color: var(--green);
    padding-left: 0;
  }

  .versus-row .v-guide {
    padding-left: 0;
    color: var(--text);
  }

  .progress-panel {
    flex-direction: column;
    align-items: flex-start;
    gap: 1.3rem;
  }

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

@media (max-width: 30rem) {
  .nav-cta {
    display: none;
  }
}

@media (max-width: 40rem) {
  .nav-inner {
    gap: 0.9rem;
    padding: 0.7rem 1rem;
  }

  .nav-logo {
    height: 26px;
  }

  .nav-actions {
    gap: 0.5rem;
  }

  .btn-sm {
    padding: 0.45rem 0.9rem;
  }

  .hero {
    padding-top: 3.5rem;
  }

  .station {
    padding-left: 2.6rem;
  }

  .level-head {
    padding-left: 2.6rem;
  }

  .track {
    left: 11px;
  }

  .node {
    left: 5px;
    top: 1.9rem;
  }

  .station-head {
    flex-wrap: wrap;
  }

  .station-side {
    flex-direction: row;
    align-items: center;
    width: 100%;
    justify-content: space-between;
  }

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

  .hero-stats {
    display: grid;
    grid-template-columns: minmax(0, 1fr) minmax(0, 1fr);
    gap: 0 1.2rem;
  }

  .stat {
    border-right: 0;
    margin-right: 0;
    padding-right: 0;
    padding-bottom: 0.6rem;
    min-width: 0;
  }

  .stat dd {
    white-space: normal;
  }

  .footer-inner {
    grid-template-columns: 1fr;
    gap: 1.6rem;
  }
}

/* ---------- Reduced motion ---------- */

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

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

  .js .reveal {
    opacity: 1;
    translate: none;
  }

  .t-tt.t-typing::after,
  .t-line.t-caret .t-tt::after {
    animation: none;
  }
}