/* ===========================================================
   apvlv — landing page
   Dark glassmorphism with neon gradient orbs.
   =========================================================== */

:root {
  --bg: #07080f;
  --bg-2: #0a0b14;
  --surface: rgba(255, 255, 255, 0.04);
  --surface-2: rgba(255, 255, 255, 0.06);
  --border: rgba(255, 255, 255, 0.08);
  --border-strong: rgba(255, 255, 255, 0.14);

  --fg: #eef0f7;
  --fg-dim: #aab0c0;
  --fg-mute: #717789;
  --fg-faint: #4b5066;

  --brand: #8b5cf6;
  --brand-2: #06b6d4;
  --brand-3: #f472b6;
  --accent: #22d3ee;
  --ok: #34d399;
  --warn: #fbbf24;
  --danger: #f87171;

  --grad-hero: linear-gradient(135deg, #8b5cf6 0%, #06b6d4 50%, #34d399 100%);
  --grad-text: linear-gradient(120deg, #c4b5fd 0%, #67e8f9 45%, #a7f3d0 100%);
  --grad-border: linear-gradient(135deg, rgba(139, 92, 246, 0.6), rgba(6, 182, 212, 0.6));

  --font-sans: "Inter", -apple-system, BlinkMacSystemFont, "Segoe UI", system-ui, sans-serif;
  --font-mono: "JetBrains Mono", ui-monospace, "SF Mono", Menlo, Consolas, monospace;

  --radius-sm: 8px;
  --radius: 14px;
  --radius-lg: 20px;
  --radius-xl: 28px;

  --container: 1200px;
  --pad: clamp(20px, 4vw, 32px);

  --t: cubic-bezier(0.4, 0, 0.2, 1);
}

* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  scroll-behavior: smooth;
  scroll-padding-top: 80px;
}

body {
  font-family: var(--font-sans);
  font-size: 16px;
  line-height: 1.6;
  color: var(--fg);
  background: var(--bg);
  background-image:
    radial-gradient(1200px 700px at 80% -10%, rgba(139, 92, 246, 0.12), transparent 60%),
    radial-gradient(900px 600px at -10% 30%, rgba(6, 182, 212, 0.10), transparent 60%);
  background-attachment: fixed;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  overflow-x: hidden;
  min-height: 100vh;
}

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

a {
  color: var(--fg);
  text-decoration: none;
  transition: color 0.2s var(--t);
}
a:hover { color: #fff; }

code, .mono { font-family: var(--font-mono); font-size: 0.92em; }
p code, li code {
  background: var(--surface);
  border: 1px solid var(--border);
  padding: 1px 6px;
  border-radius: 6px;
  color: var(--accent);
  font-size: 0.86em;
}

.container {
  width: 100%;
  max-width: var(--container);
  margin: 0 auto;
  padding: 0 var(--pad);
}

/* ============ background orbs ============ */

.bg-orbs {
  position: fixed;
  inset: 0;
  z-index: -1;
  pointer-events: none;
  overflow: hidden;
}

.orb {
  position: absolute;
  border-radius: 50%;
  filter: blur(80px);
  opacity: 0.55;
  animation: drift 22s ease-in-out infinite;
}

.orb-a {
  width: 520px; height: 520px;
  background: radial-gradient(circle at 30% 30%, #8b5cf6, transparent 70%);
  top: -120px; right: -100px;
}
.orb-b {
  width: 480px; height: 480px;
  background: radial-gradient(circle at 30% 30%, #06b6d4, transparent 70%);
  top: 30%; left: -180px;
  animation-delay: -7s;
}
.orb-c {
  width: 420px; height: 420px;
  background: radial-gradient(circle at 30% 30%, #f472b6, transparent 70%);
  bottom: -120px; right: 20%;
  animation-delay: -14s;
}

@keyframes drift {
  0%, 100% { transform: translate(0, 0) scale(1); }
  33%      { transform: translate(40px, -30px) scale(1.06); }
  66%      { transform: translate(-30px, 50px) scale(0.96); }
}

.grid-overlay {
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(255, 255, 255, 0.025) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255, 255, 255, 0.025) 1px, transparent 1px);
  background-size: 48px 48px;
  mask-image: radial-gradient(ellipse at center, #000 30%, transparent 80%);
  -webkit-mask-image: radial-gradient(ellipse at center, #000 30%, transparent 80%);
}

/* ============ nav ============ */

.nav {
  position: sticky;
  top: 0;
  z-index: 100;
  backdrop-filter: blur(18px) saturate(140%);
  -webkit-backdrop-filter: blur(18px) saturate(140%);
  background: rgba(7, 8, 15, 0.55);
  border-bottom: 1px solid transparent;
  transition: border-color 0.2s var(--t), background 0.2s var(--t);
}
.nav.is-scrolled {
  background: rgba(7, 8, 15, 0.78);
  border-bottom-color: var(--border);
}

.nav-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 64px;
  gap: 24px;
}

.brand {
  display: flex;
  align-items: center;
  gap: 10px;
  font-weight: 700;
  letter-spacing: -0.01em;
  color: #fff;
}

.brand-mark {
  width: 30px;
  height: 30px;
  display: grid;
  place-items: center;
  border-radius: 9px;
  background: var(--grad-hero);
  color: #fff;
  box-shadow: 0 6px 20px -8px rgba(139, 92, 246, 0.6);
}
.brand-mark svg { width: 18px; height: 18px; }

.brand-name {
  font-size: 17px;
  font-weight: 700;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 4px;
  margin-left: auto;
}
.nav-links a {
  padding: 8px 14px;
  font-size: 14px;
  color: var(--fg-dim);
  border-radius: 8px;
  transition: all 0.2s var(--t);
}
.nav-links a:hover {
  color: #fff;
  background: var(--surface);
}

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

.lang-toggle {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  background: var(--surface);
  border: 1px solid var(--border);
  color: var(--fg-dim);
  font: inherit;
  font-size: 12.5px;
  font-weight: 500;
  padding: 6px 10px;
  border-radius: 8px;
  cursor: pointer;
  transition: all 0.2s var(--t);
}
.lang-toggle:hover { color: #fff; border-color: var(--border-strong); }
.lang-toggle [data-lang] {
  transition: color 0.2s var(--t);
}
.lang-toggle .lang-sep { color: var(--fg-faint); }
html[lang="en"] .lang-toggle [data-lang="en"],
html[lang="zh"] .lang-toggle [data-lang="zh"] {
  color: var(--accent);
  font-weight: 600;
}

.menu-toggle {
  display: none;
  width: 38px; height: 38px;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 8px;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  gap: 4px;
  cursor: pointer;
  padding: 0;
}
.menu-toggle span {
  display: block;
  width: 16px; height: 1.5px;
  background: var(--fg);
  border-radius: 2px;
  transition: transform 0.25s var(--t), opacity 0.25s var(--t);
}
.menu-toggle[aria-expanded="true"] span:nth-child(1) { transform: translateY(5.5px) rotate(45deg); }
.menu-toggle[aria-expanded="true"] span:nth-child(2) { opacity: 0; }
.menu-toggle[aria-expanded="true"] span:nth-child(3) { transform: translateY(-5.5px) rotate(-45deg); }

/* ============ buttons ============ */

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 11px 20px;
  border-radius: 10px;
  font-size: 14.5px;
  font-weight: 500;
  letter-spacing: -0.005em;
  border: 1px solid transparent;
  cursor: pointer;
  transition: all 0.2s var(--t);
  font-family: inherit;
  white-space: nowrap;
}

.btn-sm { padding: 7px 12px; font-size: 13px; gap: 6px; }

.btn-primary {
  background: var(--grad-hero);
  color: #fff;
  border-color: transparent;
  box-shadow: 0 8px 28px -10px rgba(139, 92, 246, 0.55),
              inset 0 0 0 1px rgba(255, 255, 255, 0.12);
}
.btn-primary:hover {
  transform: translateY(-1px);
  box-shadow: 0 14px 36px -10px rgba(139, 92, 246, 0.7),
              inset 0 0 0 1px rgba(255, 255, 255, 0.2);
  color: #fff;
}

.btn-ghost {
  background: var(--surface);
  color: var(--fg);
  border-color: var(--border);
}
.btn-ghost:hover {
  background: var(--surface-2);
  border-color: var(--border-strong);
  color: #fff;
}

/* ============ hero ============ */

.hero {
  position: relative;
  padding: clamp(60px, 10vw, 120px) 0 clamp(40px, 6vw, 80px);
  text-align: center;
}

.badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 6px 14px;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 999px;
  font-size: 12.5px;
  color: var(--fg-dim);
  font-weight: 500;
  margin-bottom: 28px;
  letter-spacing: 0.01em;
}
.badge-dot {
  width: 6px; height: 6px;
  background: var(--ok);
  border-radius: 50%;
  box-shadow: 0 0 0 4px rgba(52, 211, 153, 0.15);
}

.hero-title {
  font-size: clamp(34px, 6vw, 68px);
  font-weight: 800;
  letter-spacing: -0.035em;
  line-height: 1.08;
  margin-bottom: 24px;
  max-width: 20ch;
  margin-left: auto;
  margin-right: auto;
}
.hero-title > span { display: inline; }

.gradient-text {
  background: var(--grad-text);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}

.hero-sub {
  font-size: clamp(15.5px, 1.5vw, 18px);
  color: var(--fg-dim);
  max-width: 64ch;
  margin: 0 auto 36px;
  line-height: 1.65;
}

.hero-actions {
  display: flex;
  gap: 12px;
  justify-content: center;
  flex-wrap: wrap;
  margin-bottom: 60px;
}

/* ============ hero terminal ============ */

.hero-terminal {
  max-width: 880px;
  margin: 0 auto;
  position: relative;
}

.hero-terminal::before {
  content: "";
  position: absolute;
  inset: -2px;
  border-radius: calc(var(--radius-lg) + 2px);
  background: var(--grad-hero);
  opacity: 0.6;
  filter: blur(24px);
  z-index: -1;
}

.terminal {
  background: rgba(10, 11, 20, 0.88);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border: 1px solid var(--border-strong);
  border-radius: var(--radius-lg);
  overflow: hidden;
  text-align: left;
  box-shadow: 0 30px 80px -20px rgba(0, 0, 0, 0.6);
}

.terminal-bar {
  display: flex;
  align-items: center;
  gap: 7px;
  padding: 12px 16px;
  background: rgba(255, 255, 255, 0.02);
  border-bottom: 1px solid var(--border);
}
.terminal-bar .dot {
  width: 11px; height: 11px;
  border-radius: 50%;
}
.dot.red { background: #ff5f56; }
.dot.yellow { background: #ffbd2e; }
.dot.green { background: #27c93f; }
.terminal-title {
  margin-left: 12px;
  font-family: var(--font-mono);
  font-size: 12.5px;
  color: var(--fg-mute);
}

.terminal-body {
  padding: 22px 24px;
  font-family: var(--font-mono);
  font-size: 13.5px;
  line-height: 1.75;
  color: var(--fg);
  overflow-x: auto;
}
.terminal-body code { font-family: inherit; }
.t-prompt { color: var(--brand-3); }
.t-cmd    { color: var(--accent); font-weight: 600; }
.t-arg    { color: #c4b5fd; }
.t-str    { color: #a7f3d0; }
.t-ok     { color: var(--ok); font-weight: 700; }
.t-dim    { color: var(--fg-faint); }

/* ============ sections ============ */

.section {
  padding: clamp(64px, 9vw, 110px) 0;
  position: relative;
}

.section-head {
  text-align: center;
  margin-bottom: 56px;
  max-width: 60ch;
  margin-left: auto;
  margin-right: auto;
}

.eyebrow {
  display: inline-block;
  font-size: 12.5px;
  font-weight: 600;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: 14px;
}

.section h2 {
  font-size: clamp(28px, 4.4vw, 44px);
  font-weight: 700;
  letter-spacing: -0.025em;
  line-height: 1.15;
  margin-bottom: 16px;
}

.section-sub {
  color: var(--fg-dim);
  font-size: 16px;
  margin-top: 12px;
}

/* ============ grid + cards ============ */

.grid {
  display: grid;
  gap: 18px;
}
.grid-3 { grid-template-columns: repeat(3, 1fr); }
.grid-4 { grid-template-columns: repeat(4, 1fr); }

.card {
  position: relative;
  padding: 26px 24px 28px;
  background: linear-gradient(180deg, rgba(255, 255, 255, 0.045) 0%, rgba(255, 255, 255, 0.02) 100%);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  transition: transform 0.25s var(--t), border-color 0.25s var(--t), background 0.25s var(--t);
  overflow: hidden;
}
.card::before {
  content: "";
  position: absolute;
  inset: 0;
  border-radius: inherit;
  padding: 1px;
  background: var(--grad-border);
  -webkit-mask: linear-gradient(#000 0 0) content-box, linear-gradient(#000 0 0);
  mask: linear-gradient(#000 0 0) content-box, linear-gradient(#000 0 0);
  -webkit-mask-composite: xor;
  mask-composite: exclude;
  opacity: 0;
  transition: opacity 0.3s var(--t);
}
.card:hover {
  transform: translateY(-3px);
  border-color: transparent;
}
.card:hover::before { opacity: 1; }

.card-icon {
  width: 42px;
  height: 42px;
  display: grid;
  place-items: center;
  border-radius: 11px;
  background: linear-gradient(135deg, rgba(139, 92, 246, 0.18), rgba(6, 182, 212, 0.18));
  border: 1px solid var(--border-strong);
  color: var(--accent);
  margin-bottom: 18px;
}
.card-icon svg { width: 22px; height: 22px; }

.card h3 {
  font-size: 17px;
  font-weight: 600;
  letter-spacing: -0.01em;
  margin-bottom: 8px;
  color: #fff;
}
.card p {
  color: var(--fg-dim);
  font-size: 14.5px;
  line-height: 1.65;
}

/* ============ formats ============ */

.backend {
  position: relative;
  padding: 26px 22px;
  background: linear-gradient(180deg, rgba(255,255,255,0.04), rgba(255,255,255,0.015));
  border: 1px solid var(--border);
  border-radius: var(--radius);
  transition: all 0.25s var(--t);
}
.backend:hover {
  transform: translateY(-3px);
  border-color: var(--border-strong);
  background: linear-gradient(180deg, rgba(255,255,255,0.06), rgba(255,255,255,0.02));
}

.backend-mark {
  width: 44px; height: 44px;
  border-radius: 12px;
  display: grid; place-items: center;
  margin-bottom: 16px;
  background: linear-gradient(135deg, rgba(139,92,246,0.2), rgba(34,211,238,0.2));
  border: 1px solid var(--border-strong);
  color: var(--accent);
}
.backend-mark svg { width: 24px; height: 24px; }
.backend h3 {
  font-size: 17px;
  font-weight: 600;
  color: #fff;
  margin-bottom: 10px;
}
.backend p {
  color: var(--fg-dim);
  font-size: 14px;
  line-height: 1.6;
  margin-bottom: 16px;
}
.backend-cli {
  display: block;
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--accent);
  background: rgba(0, 0, 0, 0.3);
  border: 1px solid var(--border);
  padding: 8px 10px;
  border-radius: 8px;
  overflow-x: auto;
  white-space: nowrap;
}

/* ============ keyboard tokens ============ */

kbd {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 12.5px;
  font-weight: 500;
  color: var(--accent);
  background: rgba(0, 0, 0, 0.32);
  border: 1px solid var(--border-strong);
  border-bottom-width: 2px;
  padding: 3px 8px;
  border-radius: 6px;
  white-space: nowrap;
  line-height: 1.4;
}

/* ============ command reference (tabs + rows) ============ */

.cmd-panel {
  background: rgba(10, 11, 20, 0.7);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  overflow: hidden;
  backdrop-filter: blur(10px);
}

.tabs {
  display: flex;
  border-bottom: 1px solid var(--border);
  background: rgba(255, 255, 255, 0.015);
}
.tab {
  flex: 1;
  padding: 13px 12px;
  background: transparent;
  border: none;
  color: var(--fg-mute);
  font: inherit;
  font-size: 13.5px;
  font-weight: 500;
  cursor: pointer;
  position: relative;
  transition: color 0.2s var(--t);
}
.tab:hover { color: var(--fg); }
.tab.is-active { color: #fff; }
.tab.is-active::after {
  content: "";
  position: absolute;
  bottom: -1px; left: 0; right: 0;
  height: 2px;
  background: var(--grad-hero);
}

.tabpanel { display: none; }
.tabpanel.is-active { display: block; }

.cmd-rows { display: flex; flex-direction: column; }
.cmd-row {
  display: grid;
  grid-template-columns: minmax(110px, 168px) 1fr;
  gap: 20px;
  align-items: baseline;
  padding: 13px 22px;
  border-bottom: 1px solid var(--border);
}
.cmd-row:last-child { border-bottom: none; }
.cmd-row:hover { background: rgba(255, 255, 255, 0.02); }
.cmd-row .keys { display: flex; flex-wrap: wrap; gap: 6px; }
.cmd-row p {
  color: var(--fg-dim);
  font-size: 14px;
  line-height: 1.55;
}

/* ============ settings ============ */

.settings-board {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 14px;
  margin-bottom: 18px;
}
.setting {
  padding: 16px 18px;
  background: linear-gradient(180deg, rgba(255,255,255,0.04), rgba(255,255,255,0.015));
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  transition: border-color 0.2s var(--t), background 0.2s var(--t);
}
.setting:hover {
  border-color: var(--border-strong);
  background: linear-gradient(180deg, rgba(255,255,255,0.06), rgba(255,255,255,0.02));
}
.setting kbd { margin-bottom: 10px; }
.setting p { color: var(--fg-dim); font-size: 13.5px; line-height: 1.55; }

.subhead {
  font-size: 13px;
  font-weight: 600;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--fg-mute);
  margin: 38px 0 16px;
}

/* ============ build / quickstart ============ */

.qs {
  display: grid;
  grid-template-columns: 1fr 1.4fr;
  gap: 40px;
  align-items: flex-start;
}

.qs-steps { display: flex; flex-direction: column; gap: 22px; }

.qs-step {
  display: flex;
  gap: 16px;
  align-items: flex-start;
}
.qs-num {
  flex: 0 0 auto;
  width: 32px; height: 32px;
  display: grid; place-items: center;
  border-radius: 50%;
  background: var(--grad-hero);
  color: #fff;
  font-weight: 700;
  font-size: 14px;
  box-shadow: 0 6px 18px -6px rgba(139,92,246,0.5);
}
.qs-step h4 {
  font-size: 16px;
  font-weight: 600;
  color: #fff;
  margin-bottom: 4px;
}
.qs-step p {
  font-size: 14px;
  color: var(--fg-dim);
  line-height: 1.6;
}

.qs-tabs {
  background: rgba(10, 11, 20, 0.7);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  overflow: hidden;
  backdrop-filter: blur(10px);
}

.code { background: transparent; }
.code-bar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 9px 14px;
  background: rgba(255, 255, 255, 0.02);
  border-bottom: 1px solid var(--border);
  font-size: 12px;
  color: var(--fg-mute);
}
.copy {
  background: transparent;
  border: 1px solid var(--border);
  color: var(--fg-dim);
  padding: 4px 10px;
  border-radius: 6px;
  font: inherit;
  font-size: 11.5px;
  cursor: pointer;
  transition: all 0.2s var(--t);
}
.copy:hover { color: #fff; border-color: var(--border-strong); }
.copy.is-copied { color: var(--ok); border-color: rgba(52,211,153,0.4); }

.code pre {
  padding: 18px 20px;
  overflow-x: auto;
  font-family: var(--font-mono);
  font-size: 13px;
  line-height: 1.7;
  color: var(--fg);
}
.code pre code { font-family: inherit; }
.c-comment { color: var(--fg-faint); font-style: italic; }

/* ============ CTA ============ */

.cta-section { padding-top: 40px; padding-bottom: 100px; }

.cta {
  position: relative;
  text-align: center;
  padding: 56px 32px;
  border-radius: var(--radius-xl);
  background:
    radial-gradient(ellipse at top, rgba(139, 92, 246, 0.18), transparent 70%),
    radial-gradient(ellipse at bottom right, rgba(6, 182, 212, 0.15), transparent 60%),
    rgba(10, 11, 20, 0.6);
  border: 1px solid var(--border-strong);
  overflow: hidden;
  backdrop-filter: blur(12px);
}
.cta::before {
  content: "";
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(255,255,255,0.03) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255,255,255,0.03) 1px, transparent 1px);
  background-size: 32px 32px;
  mask-image: radial-gradient(circle at center, #000 30%, transparent 75%);
  -webkit-mask-image: radial-gradient(circle at center, #000 30%, transparent 75%);
  pointer-events: none;
}
.cta > * { position: relative; }
.cta h2 {
  font-size: clamp(26px, 4vw, 38px);
  font-weight: 700;
  letter-spacing: -0.025em;
  margin-bottom: 14px;
}
.cta p {
  color: var(--fg-dim);
  font-size: 16px;
  max-width: 56ch;
  margin: 0 auto 28px;
}
.cta-actions {
  display: flex;
  justify-content: center;
  gap: 12px;
  flex-wrap: wrap;
}

/* ============ footer ============ */

.footer {
  border-top: 1px solid var(--border);
  padding: 56px 0 28px;
  background: rgba(7, 8, 15, 0.6);
  backdrop-filter: blur(10px);
}
.footer-inner {
  display: grid;
  grid-template-columns: 1fr 2fr;
  gap: 40px;
  margin-bottom: 40px;
}
.footer-tag {
  color: var(--fg-mute);
  font-size: 13.5px;
  margin-top: 10px;
}
.footer-cols {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 28px;
}
.footer-cols h5 {
  font-size: 12.5px;
  font-weight: 600;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--fg-mute);
  margin-bottom: 14px;
}
.footer-cols a {
  display: block;
  color: var(--fg-dim);
  font-size: 14px;
  margin-bottom: 8px;
}
.footer-cols a:hover { color: #fff; }

.footer-bottom {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding-top: 24px;
  border-top: 1px solid var(--border);
  color: var(--fg-mute);
  font-size: 13px;
}
.footer-build { color: var(--fg-faint); }

/* ============ responsive ============ */

@media (max-width: 980px) {
  .grid-3 { grid-template-columns: repeat(2, 1fr); }
  .grid-4 { grid-template-columns: repeat(2, 1fr); }
  .qs { grid-template-columns: 1fr; }
  .settings-board { grid-template-columns: repeat(2, 1fr); }
  .footer-inner { grid-template-columns: 1fr; }
}

@media (max-width: 720px) {
  .nav-links { display: none; }
  .menu-toggle { display: flex; }
  .nav-actions .btn { display: none; }

  .nav.menu-open + main { pointer-events: none; }
  .nav.menu-open .nav-links {
    display: flex;
    position: absolute;
    top: 64px; left: 0; right: 0;
    flex-direction: column;
    padding: 14px 20px;
    background: rgba(7, 8, 15, 0.96);
    backdrop-filter: blur(20px);
    border-bottom: 1px solid var(--border);
    gap: 4px;
    margin-left: 0;
  }
  .nav.menu-open .nav-links a {
    padding: 12px 14px;
    font-size: 15px;
  }

  .grid-3, .grid-4 { grid-template-columns: 1fr; }
  .settings-board { grid-template-columns: 1fr; }

  .cmd-row { grid-template-columns: 1fr; gap: 8px; }

  .footer-cols { grid-template-columns: repeat(2, 1fr); }
  .footer-bottom { flex-direction: column; gap: 8px; text-align: center; }

  .terminal-body { font-size: 12px; padding: 16px; }
}

/* ============ language visibility ============ */

html[lang="en"] [data-en],
html[lang="zh"] [data-zh] { display: revert; }

html[lang="en"] [data-zh]:not([data-en]),
html[lang="zh"] [data-en]:not([data-zh]) { display: none; }

html[lang="zh"] .en-only { display: none; }
html[lang="en"] .zh-only { display: none; }

/* selection */
::selection { background: rgba(139, 92, 246, 0.4); color: #fff; }

/* scrollbar */
::-webkit-scrollbar { width: 10px; height: 10px; }
::-webkit-scrollbar-track { background: transparent; }
::-webkit-scrollbar-thumb { background: rgba(255,255,255,0.08); border-radius: 10px; }
::-webkit-scrollbar-thumb:hover { background: rgba(255,255,255,0.14); }

/* reduced motion */
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
  html { scroll-behavior: auto; }
}