/* GhostPen site: the app's own palette (frontend/src/styles.css). */
:root {
  --night: #111317;
  --ink: #16181d;
  --paper: #e6e8ec;
  --blue: #6d8bff;
  --blue-light: #9fb3ff;

  --bg: var(--night);
  --surface: var(--ink);
  --surface-2: #1d2026;
  --text: var(--paper);
  --muted: rgba(230, 232, 236, 0.68);
  --faint: rgba(230, 232, 236, 0.44);
  --border: rgba(230, 232, 236, 0.09);
  --border-strong: rgba(230, 232, 236, 0.16);
  --accent: var(--blue);
  --accent-2: var(--blue-light);
  --accent-ink: #0b0e16;
  --glow: rgba(109, 139, 255, 0.24);
  --code-bg: #14161b;
  --shadow: 0 1px 0 rgba(255, 255, 255, 0.03) inset, 0 20px 40px -24px rgba(0, 0, 0, 0.6);

  --font: "Inter", ui-sans-serif, system-ui, -apple-system, "Segoe UI", sans-serif;
  --mono: "JetBrains Mono", ui-monospace, "SFMono-Regular", Menlo, monospace;
  --radius: 12px;
  --max: 1200px;
  color-scheme: dark;
}

@media (prefers-color-scheme: light) {
  :root {
    --bg: #f7f8fb;
    --surface: #ffffff;
    --surface-2: #eef1f7;
    --text: #1b1e24;
    --muted: rgba(27, 30, 36, 0.68);
    --faint: rgba(27, 30, 36, 0.45);
    --border: rgba(27, 30, 36, 0.09);
    --border-strong: rgba(27, 30, 36, 0.16);
    --accent: #3b6cff;
    --accent-2: var(--blue);
    --glow: rgba(59, 108, 255, 0.2);
    --code-bg: #16181d;
    --shadow: 0 20px 40px -28px rgba(27, 30, 36, 0.35);
    color-scheme: light;
  }
}

* { box-sizing: border-box; }
html { scroll-padding-top: 80px; -webkit-text-size-adjust: 100%; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font: 400 17px/1.68 var(--font);
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}
img { max-width: 100%; height: auto; }
a { color: var(--accent); text-decoration: none; }
a:hover { color: var(--accent-2); }
:focus-visible { outline: 2px solid var(--accent); outline-offset: 2px; border-radius: 4px; }
code, pre { font-family: var(--mono); }
:not(pre) > code {
  font-size: 0.88em;
  background: var(--surface-2);
  border: 1px solid var(--border);
  border-radius: 6px;
  padding: 0.1em 0.38em;
}

/* ---------- Top bar ---------- */
.topbar {
  position: sticky; top: 0; z-index: 20;
  background: color-mix(in srgb, var(--bg) 78%, transparent);
  backdrop-filter: saturate(160%) blur(14px);
  -webkit-backdrop-filter: saturate(160%) blur(14px);
  border-bottom: 1px solid var(--border);
}
.topbar-inner {
  max-width: var(--max); margin: 0 auto; height: 64px;
  display: flex; align-items: center; gap: 24px; padding: 0 24px;
}
.brand { display: flex; align-items: center; gap: 10px; color: var(--text); }
.brand:hover { color: var(--text); }
.brand-mark { border-radius: 7px; }
.brand-name { font-weight: 800; font-size: 22px; letter-spacing: -0.04em; }
.topnav { margin-left: auto; display: flex; align-items: center; gap: 4px; }
.topnav a {
  color: var(--muted); font-weight: 500; font-size: 16.5px;
  padding: 8px 12px; border-radius: 8px;
}
.topnav a:hover, .topnav a.active { color: var(--text); background: var(--surface-2); }
.topnav-gh { border: 1px solid var(--border-strong); margin-left: 6px; }
.version-badge {
  font: 500 12.5px var(--mono); color: var(--accent);
  border: 1px solid color-mix(in srgb, var(--accent) 45%, transparent);
  border-radius: 999px; padding: 3px 9px; margin-left: 6px;
}
.menu-toggle { display: none; margin-left: auto; background: none; border: 0; padding: 8px; cursor: pointer; }
.menu-toggle span { display: block; width: 20px; height: 2px; background: var(--text); margin: 4px 0; border-radius: 2px; }

/* ---------- Buttons ---------- */
.btn {
  display: inline-flex; align-items: center; justify-content: center;
  font-weight: 600; font-size: 16.5px; padding: 12px 20px; border-radius: 10px;
  transition: transform .15s ease, background .15s ease, border-color .15s ease;
}
.btn:hover { transform: translateY(-1px); }
.btn-primary {
  color: var(--accent-ink);
  background: linear-gradient(180deg, var(--blue-light), var(--blue));
  box-shadow: 0 8px 24px -10px var(--glow);
}
.btn-primary:hover { color: var(--accent-ink); }
.btn-ghost { color: var(--text); border: 1px solid var(--border-strong); background: var(--surface); }
.btn-ghost:hover { color: var(--text); border-color: var(--accent); }

/* ---------- Home ---------- */
.hero { position: relative; overflow: hidden; padding: 96px 24px 72px; text-align: center; }
.hero-glow {
  position: absolute; left: 50%; top: -220px; width: 900px; height: 700px; transform: translateX(-50%);
  background: radial-gradient(closest-side, var(--glow), transparent 70%);
  pointer-events: none;
}
.hero-inner { position: relative; max-width: 860px; margin: 0 auto; }
.hero-mark { width: 96px; height: 96px; border-radius: 22px; box-shadow: 0 18px 50px -18px var(--glow); }
.eyebrow {
  margin: 28px 0 0; font: 500 13px var(--mono); letter-spacing: 0.02em; color: var(--faint);
}
.hero-title {
  margin: 14px 0 0; font-size: clamp(40px, 7vw, 72px); line-height: 1.04;
  font-weight: 800; letter-spacing: -0.045em;
}
.accent {
  background: linear-gradient(180deg, var(--blue-light), var(--blue));
  -webkit-background-clip: text; background-clip: text; color: transparent;
}
.hero-lead { margin: 22px auto 0; max-width: 640px; font-size: 19px; color: var(--muted); }
.hero-actions { display: flex; gap: 12px; justify-content: center; flex-wrap: wrap; margin-top: 32px; }
.install-tabs { display: flex; justify-content: center; gap: 4px; margin: 36px auto 0; }
.install-tab {
  font: 500 13px var(--font); color: var(--muted); background: transparent;
  border: 1px solid transparent; border-radius: 999px; padding: 6px 14px; cursor: pointer;
}
.install-tab:hover { color: var(--text); }
.install-tab[aria-selected="true"] { color: var(--text); background: var(--surface); border-color: var(--border-strong); }
.install[hidden] { display: none; }
.install {
  display: flex; align-items: center; gap: 12px; margin: 12px auto 0; max-width: 720px;
  background: var(--code-bg); border: 1px solid var(--border-strong); border-radius: var(--radius);
  padding: 10px 10px 10px 18px; text-align: left; box-shadow: var(--shadow);
}
.install code { background: none; border: 0; padding: 0; flex: 1; min-width: 0; overflow-x: auto; white-space: nowrap; color: #e6e8ec; font-size: 15px; scrollbar-width: none; }
.install-prompt { color: var(--blue); font-family: var(--mono); user-select: none; }
.copy-btn {
  font: 500 12.5px var(--font); color: #e6e8ec; background: rgba(230, 232, 236, 0.08);
  border: 1px solid rgba(230, 232, 236, 0.14); border-radius: 8px; padding: 7px 12px; cursor: pointer;
}
.copy-btn:hover { border-color: var(--blue); }
.copy-btn.copied { color: var(--blue); }

.section { max-width: var(--max); margin: 0 auto; padding: 72px 24px; }
.section-head { max-width: 640px; margin-bottom: 36px; }
.section-head h2 { margin: 0; font-size: clamp(28px, 4vw, 38px); letter-spacing: -0.035em; line-height: 1.15; }
.section-head p { margin: 12px 0 0; color: var(--muted); font-size: 17px; }

.feature-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 16px; }
.feature {
  background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius);
  padding: 24px; transition: border-color .2s ease, transform .2s ease;
}
.feature:hover { border-color: color-mix(in srgb, var(--accent) 45%, transparent); transform: translateY(-2px); }
.feature-icon svg { width: 20px; height: 20px; stroke: currentColor; fill: none; stroke-width: 1.8; stroke-linecap: round; stroke-linejoin: round; }
.feature-icon {
  width: 40px; height: 40px; display: grid; place-items: center;
  border-radius: 10px; background: color-mix(in srgb, var(--accent) 14%, transparent);
  color: var(--accent);
}
.feature h3 { margin: 16px 0 6px; font-size: 17px; letter-spacing: -0.01em; }
.feature p { margin: 0; color: var(--muted); font-size: 16px; }

.code-pair { display: grid; grid-template-columns: 1fr 1fr; gap: 16px; }
.code-card { margin: 0; background: var(--code-bg); border: 1px solid var(--border-strong); border-radius: var(--radius); overflow: hidden; box-shadow: var(--shadow); }
.code-card figcaption {
  display: flex; align-items: center; gap: 8px; padding: 10px 16px;
  font: 500 12.5px var(--mono); color: rgba(230, 232, 236, 0.6);
  border-bottom: 1px solid rgba(230, 232, 236, 0.08);
}
.dot { width: 8px; height: 8px; border-radius: 50%; background: var(--blue); }
.code-card pre { margin: 0; padding: 18px 20px; overflow-x: auto; font-size: 14.5px; line-height: 1.7; color: #e6e8ec; }

.shots { display: grid; grid-template-columns: repeat(3, 1fr); gap: 16px; }
.shots figure { margin: 0; }
.shots img {
  display: block; width: 100%; aspect-ratio: 4 / 3; object-fit: cover; object-position: top;
  border-radius: var(--radius); border: 1px solid var(--border-strong); background: var(--surface);
}
.shots figcaption { margin-top: 10px; font-size: 15px; color: var(--muted); }
.shots figcaption strong { color: var(--text); }

.platforms { display: grid; grid-template-columns: repeat(3, 1fr); gap: 16px; }
.platform { background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius); padding: 24px; }
.platform h3 { margin: 0 0 6px; font-size: 18px; }
.platform p { margin: 0 0 16px; color: var(--muted); font-size: 16px; }
.status, .badge-planned {
  display: inline-block; font: 600 12px var(--font); border-radius: 999px; padding: 3px 10px;
}
.status-ok { color: #3ecf8e; background: rgba(62, 207, 142, 0.12); }
.status-beta { color: var(--accent); background: color-mix(in srgb, var(--accent) 14%, transparent); }
.status-planned, .badge-planned { color: var(--muted); background: var(--surface-2); border: 1px solid var(--border-strong); }

.table-wrap { overflow-x: auto; border: 1px solid var(--border); border-radius: var(--radius); }
table { width: 100%; border-collapse: collapse; font-size: 16px; }
th, td { text-align: left; padding: 12px 16px; border-bottom: 1px solid var(--border); vertical-align: top; }
th { font-weight: 600; background: var(--surface); }
tr:last-child td { border-bottom: 0; }
.compare td:first-child { color: var(--muted); white-space: nowrap; }

.cta {
  max-width: 880px; margin: 24px auto 96px; padding: 56px 24px; text-align: center;
  border: 1px solid var(--border-strong); border-radius: 20px;
  background: radial-gradient(600px 240px at 50% 0%, var(--glow), transparent 70%), var(--surface);
}
.cta h2 { margin: 0; font-size: clamp(26px, 4vw, 34px); letter-spacing: -0.03em; }
.cta p { color: var(--muted); margin: 12px 0 0; }

/* ---------- Docs ---------- */
.docs {
  max-width: var(--max); margin: 0 auto; padding: 0 24px;
  display: grid; grid-template-columns: 232px minmax(0, 1fr) 200px; gap: 48px;
}
.sidebar, .toc { position: sticky; top: 64px; align-self: start; max-height: calc(100vh - 64px); overflow-y: auto; padding: 32px 0; }
.sidebar h4, .toc h4 {
  margin: 20px 0 8px; font: 600 12px var(--font); text-transform: uppercase; letter-spacing: 0.08em; color: var(--faint);
}
.sidebar h4:first-child, .toc h4:first-child { margin-top: 0; }
.sidebar a {
  display: block; color: var(--muted); font-size: 16px; padding: 6px 12px; margin-left: -12px;
  border-radius: 8px; border-left: 2px solid transparent;
}
.sidebar a:hover { color: var(--text); background: var(--surface); }
.sidebar a.active { color: var(--text); background: var(--surface); border-left-color: var(--accent); font-weight: 500; }
.toc ul { list-style: none; margin: 0; padding: 0; }
.toc ul ul { padding-left: 12px; }
.toc a { display: block; color: var(--faint); font-size: 14.5px; padding: 4px 0; }
.toc a:hover { color: var(--text); }

.doc { padding: 40px 0 72px; min-width: 0; }
.prose { max-width: 74ch; }
.prose h1 { font-size: clamp(32px, 4.5vw, 44px); letter-spacing: -0.04em; line-height: 1.1; margin: 0 0 12px; }
.doc-lead { font-size: 19px; color: var(--muted); margin: 0 0 32px; }
.prose .content h1, .prose h2 { font-size: 26px; letter-spacing: -0.025em; margin: 48px 0 12px; padding-top: 8px; border-top: 1px solid var(--border); padding-top: 28px; }
.prose .content h2, .prose h3 { font-size: 19px; letter-spacing: -0.01em; margin: 32px 0 8px; }
.prose p, .prose li { color: color-mix(in srgb, var(--text) 88%, transparent); }
.prose ul, .prose ol { padding-left: 1.3em; }
.prose li { margin: 4px 0; }
.prose li::marker { color: var(--accent); }
.prose blockquote {
  margin: 20px 0; padding: 12px 18px; border-left: 3px solid var(--accent);
  background: var(--surface); border-radius: 0 10px 10px 0; color: var(--muted);
}
.prose blockquote p { margin: 6px 0; }
.prose table { margin: 20px 0; border: 1px solid var(--border); border-radius: var(--radius); border-collapse: separate; border-spacing: 0; width: 100%; }
.prose .content { overflow-wrap: anywhere; }
.prose img { border-radius: var(--radius); border: 1px solid var(--border-strong); }
.prose pre {
  position: relative; margin: 20px 0; padding: 18px 20px; overflow-x: auto;
  background: var(--code-bg); color: #e6e8ec; border: 1px solid var(--border-strong);
  border-radius: var(--radius); font-size: 15px; line-height: 1.7;
}
.prose pre code { background: none; border: 0; padding: 0; font-size: inherit; color: inherit; }
.prose pre .copy-btn { position: absolute; top: 8px; right: 8px; opacity: 0; transition: opacity .15s; }
.prose pre:hover .copy-btn { opacity: 1; }
.doc-foot { margin-top: 48px; font-size: 15px; }
.edit-link { color: var(--faint); }
.pager { display: grid; grid-template-columns: 1fr 1fr; gap: 16px; margin-top: 24px; }
.pager a { border: 1px solid var(--border); border-radius: var(--radius); padding: 14px 18px; color: var(--text); background: var(--surface); }
.pager a:hover { border-color: var(--accent); }
.pager small { display: block; color: var(--faint); font-size: 13.5px; }
.pager-next { grid-column: 2; text-align: right; }

/* ---------- Footer ---------- */
.site-footer { border-top: 1px solid var(--border); padding: 48px 0 32px; }
.footer-inner { max-width: var(--max); margin: 0 auto; padding: 0 24px; display: flex; justify-content: space-between; gap: 32px; flex-wrap: wrap; }
.footer-brand { display: flex; align-items: center; align-content: flex-start; gap: 8px; flex-wrap: wrap; max-width: 320px; font-weight: 800; letter-spacing: -0.03em; font-size: 18px; }
.footer-brand p { flex-basis: 100%; margin: 6px 0 0; font-weight: 400; letter-spacing: 0; font-size: 15px; color: var(--muted); }
.footer-cols { display: flex; gap: 64px; }
.footer-cols h4 { margin: 0 0 10px; font-size: 14px; color: var(--faint); text-transform: uppercase; letter-spacing: 0.08em; }
.footer-cols a { display: block; color: var(--muted); font-size: 15px; padding: 3px 0; }
.footer-cols a:hover { color: var(--text); }
.footer-legal { max-width: var(--max); margin: 32px auto 0; padding: 0 24px; color: var(--faint); font-size: 14px; }
.footer-legal a { color: var(--muted); }

/* ---------- Responsive ---------- */
@media (max-width: 1180px) {
  .docs { grid-template-columns: 220px minmax(0, 1fr); }
  .toc { display: none; }
}
@media (max-width: 900px) {
  .menu-toggle { display: block; }
  .topnav {
    display: none; position: absolute; top: 64px; left: 0; right: 0; flex-direction: column; align-items: stretch;
    background: var(--bg); border-bottom: 1px solid var(--border); padding: 8px 16px 16px;
  }
  .topnav.open { display: flex; }
  .topnav-gh, .version-badge { margin-left: 0; }
  .version-badge { align-self: flex-start; margin-top: 8px; }
  .feature-grid, .platforms, .shots { grid-template-columns: 1fr 1fr; }
  .code-pair { grid-template-columns: 1fr; }
  .docs { grid-template-columns: 1fr; gap: 0; padding: 0 16px; }
  .sidebar { position: static; max-height: none; padding: 20px 0 0; border-bottom: 1px solid var(--border); }
  .sidebar nav { display: flex; flex-wrap: wrap; gap: 4px; }
  .sidebar h4 { flex-basis: 100%; margin: 8px 0 4px; }
  .sidebar a { margin: 0; border: 1px solid var(--border); border-radius: 999px; padding: 4px 12px; font-size: 15px; }
  .sidebar a.active { border-color: var(--accent); }
}
@media (max-width: 600px) {
  .topbar-inner { padding: 0 16px; }
  .hero { padding: 64px 16px 48px; }
  .section { padding: 48px 16px; }
  .feature-grid, .platforms, .shots { grid-template-columns: 1fr; }
  .footer-cols { gap: 40px; }
  .cta { margin: 16px 16px 64px; }
}

/* ---------- GhostPen landing ---------- */
.hero-shot {
  position: relative; max-width: 1040px; margin: 8px auto 0; padding: 0 24px;
  display: grid; grid-template-columns: 1.9fr 1fr; gap: 20px; align-items: end;
}
.hero-shot img { display: block; border-radius: 14px; border: 1px solid var(--border-strong); box-shadow: 0 30px 80px -30px rgba(0, 0, 0, 0.7), 0 0 0 1px rgba(255, 255, 255, 0.02); }
.download { margin-top: 32px; }
.download-main { display: inline-flex; flex-direction: column; align-items: center; gap: 8px; }
.download-note { font-size: 14.5px; color: var(--faint); }
.download-note a { color: var(--muted); text-decoration: underline; text-underline-offset: 2px; }
.btn-lg { font-size: 16.5px; padding: 15px 26px; border-radius: 12px; gap: 10px; }
.btn svg { width: 18px; height: 18px; stroke: currentColor; fill: none; stroke-width: 2; stroke-linecap: round; stroke-linejoin: round; }

.steps { display: grid; grid-template-columns: repeat(3, 1fr); gap: 16px; counter-reset: step; }
.step { background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius); padding: 24px; }
.step::before {
  counter-increment: step; content: counter(step);
  display: grid; place-items: center; width: 32px; height: 32px; border-radius: 50%;
  font: 700 15px var(--font); color: var(--accent-ink); background: linear-gradient(180deg, var(--blue-light), var(--blue));
}
.step h3 { margin: 14px 0 6px; font-size: 17px; }
.step p { margin: 0; color: var(--muted); font-size: 16px; }
kbd {
  font: 500 0.82em var(--mono); padding: 0.12em 0.45em; border-radius: 6px;
  background: var(--surface-2); border: 1px solid var(--border-strong); border-bottom-width: 2px;
}

.split { display: grid; grid-template-columns: 1fr 1fr; gap: 48px; align-items: center; }
.split + .split { margin-top: 72px; }
.split.reverse .split-text { order: 2; }
.split-text h3 { margin: 0; font-size: clamp(24px, 3vw, 30px); letter-spacing: -0.03em; line-height: 1.2; }
.split-text p { color: var(--muted); font-size: 16.5px; }
.split-text ul { padding-left: 1.2em; color: var(--muted); }
.split-text li { margin: 6px 0; }
.split-text li::marker { color: var(--accent); }
.split img { border-radius: 14px; border: 1px solid var(--border-strong); box-shadow: var(--shadow); }
.tag { display: inline-block; font: 600 12px var(--font); letter-spacing: 0.02em; color: var(--accent); background: color-mix(in srgb, var(--accent) 14%, transparent); border-radius: 999px; padding: 3px 10px; margin-bottom: 14px; }

.downloads { display: grid; grid-template-columns: repeat(3, 1fr); gap: 16px; }
.dl-card { background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius); padding: 24px; display: flex; flex-direction: column; gap: 10px; }
.dl-card.current { border-color: color-mix(in srgb, var(--accent) 55%, transparent); box-shadow: 0 0 0 1px color-mix(in srgb, var(--accent) 30%, transparent) inset; }
.dl-card h3 { margin: 0; font-size: 18px; }
.dl-card p { margin: 0; color: var(--muted); font-size: 15.5px; }
.dl-links { display: flex; flex-direction: column; gap: 8px; margin-top: 6px; }
.dl-links a {
  display: flex; justify-content: space-between; align-items: center; gap: 12px;
  padding: 10px 14px; border: 1px solid var(--border-strong); border-radius: 10px; color: var(--text); font-weight: 500; font-size: 15.5px;
}
.dl-links a:hover { border-color: var(--accent); color: var(--text); }
.dl-links small { color: var(--faint); font: 500 12px var(--mono); }
.dl-empty { color: var(--faint); font-size: 15px; }

.stat-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 16px; }
.stat { background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius); padding: 20px; }
.stat b { display: block; font-size: 28px; letter-spacing: -0.03em; }
.stat span { color: var(--muted); font-size: 15px; }

@media (max-width: 900px) {
  .hero-shot, .split, .steps, .downloads { grid-template-columns: 1fr; }
  .split.reverse .split-text { order: 0; }
  .stat-grid { grid-template-columns: 1fr 1fr; }
}