/* ============================================================
   Zhongwen Hover — Dream Run × Cyber Rain theme
   ============================================================ */
:root {
  --bg: #07061a;
  --bg-2: #0b0824;
  --fg: #eef0ff;
  --fg-muted: #a3a6c8;
  --cyan: #5ef2e0;
  --violet: #a78bfa;
  --pink: #f472b6;
  --amber: #ffd166;
  --card: rgba(255, 255, 255, 0.045);
  --card-hover: rgba(255, 255, 255, 0.075);
  --border: rgba(255, 255, 255, 0.10);
  --border-glow: rgba(94, 242, 224, 0.35);
  --shadow: 0 20px 60px rgba(3, 2, 20, 0.6);
  --tone1: #ff6b6b;
  --tone2: #ffa94d;
  --tone3: #69db7c;
  --tone4: #74c0fc;
  --tone5: #adb5bd;
}

* { box-sizing: border-box; }
html, body { margin: 0; padding: 0; }
html { scroll-behavior: smooth; }

body {
  font: 16px/1.65 "Inter", -apple-system, BlinkMacSystemFont, "SF Pro Text", "Helvetica Neue", Arial, "PingFang SC", "Microsoft YaHei", sans-serif;
  color: var(--fg);
  background: var(--bg);
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
}

/* ---------- background layers ---------- */
.bg-sky {
  position: fixed; inset: 0; z-index: -3;
  background:
    radial-gradient(1200px 700px at 75% -10%, rgba(167, 139, 250, 0.22), transparent 60%),
    radial-gradient(1000px 600px at 10% 20%, rgba(94, 242, 224, 0.12), transparent 60%),
    radial-gradient(900px 900px at 50% 110%, rgba(244, 114, 182, 0.16), transparent 60%),
    linear-gradient(180deg, #050413 0%, var(--bg) 45%, #0d0724 100%);
}
.bg-stars {
  position: fixed; inset: 0; z-index: -2; pointer-events: none;
  background-image:
    radial-gradient(1px 1px at 12% 22%, rgba(255,255,255,.8), transparent),
    radial-gradient(1px 1px at 34% 8%,  rgba(255,255,255,.55), transparent),
    radial-gradient(1.5px 1.5px at 58% 16%, rgba(255,255,255,.7), transparent),
    radial-gradient(1px 1px at 76% 30%, rgba(255,255,255,.5), transparent),
    radial-gradient(1px 1px at 88% 12%, rgba(255,255,255,.65), transparent),
    radial-gradient(1.5px 1.5px at 25% 42%, rgba(255,255,255,.4), transparent),
    radial-gradient(1px 1px at 66% 48%, rgba(255,255,255,.45), transparent),
    radial-gradient(1px 1px at 45% 30%, rgba(255,255,255,.55), transparent),
    radial-gradient(1px 1px at 5% 60%,  rgba(255,255,255,.35), transparent),
    radial-gradient(1.5px 1.5px at 93% 55%, rgba(255,255,255,.5), transparent);
  animation: twinkle 6s ease-in-out infinite alternate;
}
@keyframes twinkle { from { opacity: .55; } to { opacity: 1; } }

#rain {
  position: fixed; inset: 0; z-index: -1;
  pointer-events: none;
  opacity: 0.55;
}

::selection { background: rgba(94, 242, 224, 0.3); }

a { color: var(--cyan); text-decoration: none; }
a:hover { color: #9df8ec; text-shadow: 0 0 12px rgba(94, 242, 224, 0.5); }

/* ---------- nav ---------- */
.topnav {
  position: sticky; top: 0; z-index: 50;
  display: flex; justify-content: space-between; align-items: center;
  max-width: 1120px; margin: 0 auto; padding: 14px 24px;
  backdrop-filter: blur(14px); -webkit-backdrop-filter: blur(14px);
  background: rgba(7, 6, 26, 0.55);
  border-bottom: 1px solid var(--border);
}
.topnav .brand {
  display: flex; align-items: center; gap: 10px;
  font-family: "Unbounded", "Inter", sans-serif;
  font-weight: 600; font-size: 15px; letter-spacing: 0.04em;
  color: var(--fg);
}
.topnav .brand .glyph {
  display: inline-grid; place-items: center;
  width: 30px; height: 30px; border-radius: 9px;
  font-size: 15px; font-weight: 700;
  background: linear-gradient(135deg, var(--cyan), var(--violet));
  color: #0a0820;
  box-shadow: 0 0 18px rgba(94, 242, 224, 0.45);
}
.topnav .links a {
  margin-left: 20px; color: var(--fg-muted); font-size: 14px;
  transition: color .2s, text-shadow .2s;
}
.topnav .links a:hover { color: var(--cyan); text-shadow: 0 0 10px rgba(94,242,224,.5); }

/* ---------- hero ---------- */
.hero {
  position: relative;
  text-align: center;
  padding: 110px 24px 150px;
  overflow: hidden;
}
.hero-sun {
  position: absolute; left: 50%; bottom: -330px;
  width: 460px; height: 460px; transform: translateX(-50%);
  border-radius: 50%;
  background: linear-gradient(180deg, #ffe29a 0%, #ff9a8b 30%, var(--pink) 60%, var(--violet) 100%);
  -webkit-mask-image: repeating-linear-gradient(180deg, #000 0 26px, transparent 26px 34px);
  mask-image: repeating-linear-gradient(180deg, #000 0 26px, transparent 26px 34px);
  filter: blur(0.4px);
  opacity: 0.85;
  box-shadow: 0 0 120px 40px rgba(244, 114, 182, 0.35);
  animation: sunbreathe 8s ease-in-out infinite alternate;
  pointer-events: none;
}
@keyframes sunbreathe {
  from { box-shadow: 0 0 100px 30px rgba(244,114,182,.3); }
  to   { box-shadow: 0 0 150px 60px rgba(167,139,250,.4); }
}
.hero-grid {
  position: absolute; left: -25%; right: -25%; bottom: -2px; height: 300px;
  transform: perspective(340px) rotateX(62deg);
  transform-origin: bottom;
  background-image:
    linear-gradient(rgba(94, 242, 224, 0.22) 1px, transparent 1px),
    linear-gradient(90deg, rgba(94, 242, 224, 0.22) 1px, transparent 1px);
  background-size: 44px 44px;
  animation: gridrun 3.2s linear infinite;
  -webkit-mask-image: linear-gradient(180deg, transparent, #000 35%);
  mask-image: linear-gradient(180deg, transparent, #000 35%);
  pointer-events: none;
}
@keyframes gridrun { from { background-position: 0 0; } to { background-position: 0 44px; } }

.hero-inner { position: relative; z-index: 2; }
.hero .kicker {
  display: inline-block;
  font-family: "JetBrains Mono", ui-monospace, monospace;
  font-size: 12px; letter-spacing: 0.28em; text-transform: uppercase;
  color: var(--cyan);
  border: 1px solid rgba(94, 242, 224, 0.35);
  padding: 7px 16px; border-radius: 999px;
  background: rgba(94, 242, 224, 0.07);
  box-shadow: 0 0 24px rgba(94, 242, 224, 0.15) inset;
}
.hero h1 {
  margin: 26px auto 18px; max-width: 780px;
  font-family: "Unbounded", "Inter", sans-serif;
  font-size: clamp(34px, 5.6vw, 60px);
  font-weight: 700; line-height: 1.12; letter-spacing: -0.01em;
  background: linear-gradient(100deg, #fff 10%, var(--cyan) 38%, var(--violet) 65%, var(--pink) 90%);
  -webkit-background-clip: text; background-clip: text; color: transparent;
  filter: drop-shadow(0 0 26px rgba(167, 139, 250, 0.35));
}
.hero .tagline {
  margin: 0 auto 34px; max-width: 600px;
  color: var(--fg-muted); font-size: 18px; line-height: 1.6;
}
.hero .tagline .zh { color: var(--fg); }
.cta-row { display: flex; gap: 14px; justify-content: center; flex-wrap: wrap; }
.cta {
  display: inline-flex; align-items: center; gap: 10px;
  padding: 15px 28px; border-radius: 14px;
  font-weight: 700; font-size: 15px; color: #0a0820;
  background: linear-gradient(135deg, var(--cyan), #38bdf8);
  box-shadow: 0 0 32px rgba(94, 242, 224, 0.4), 0 10px 30px rgba(0,0,0,.4);
  transition: transform .18s ease, box-shadow .18s ease;
}
.cta:hover {
  transform: translateY(-2px);
  color: #0a0820;
  box-shadow: 0 0 48px rgba(94, 242, 224, 0.6), 0 14px 34px rgba(0,0,0,.45);
}
.cta.ghost {
  color: var(--fg);
  background: rgba(255,255,255,0.05);
  border: 1px solid var(--border);
  box-shadow: none;
}
.cta.ghost:hover { border-color: var(--border-glow); box-shadow: 0 0 26px rgba(94,242,224,.18); color: var(--cyan); }
.hero .sub {
  display: block; margin-top: 20px;
  color: var(--fg-muted); font-size: 13px;
  font-family: "JetBrains Mono", ui-monospace, monospace;
}

/* ---------- generic layout ---------- */
main { max-width: 1080px; margin: 0 auto; padding: 0 24px 90px; position: relative; z-index: 2; }
main.narrow { max-width: 800px; }

section { margin-top: 64px; }
.section-head { text-align: center; margin-bottom: 34px; }
.section-head .label {
  font-family: "JetBrains Mono", ui-monospace, monospace;
  font-size: 11px; letter-spacing: 0.3em; text-transform: uppercase;
  color: var(--violet);
}
h2 {
  margin: 8px 0 10px;
  font-family: "Unbounded", "Inter", sans-serif;
  font-size: clamp(22px, 3.2vw, 30px); font-weight: 600; letter-spacing: -0.01em;
}
h3 { font-size: 16px; margin: 24px 0 6px; }
p, ul { margin: 8px 0; }
ul { padding-left: 22px; }
li { margin: 4px 0; }
code {
  font: 13px/1.4 "JetBrains Mono", ui-monospace, Menlo, monospace;
  background: rgba(94, 242, 224, 0.08);
  color: var(--cyan);
  padding: 1px 6px; border-radius: 5px;
  border: 1px solid rgba(94, 242, 224, 0.18);
}
.muted { color: var(--fg-muted); }
.center { text-align: center; }

.panel {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 20px;
  padding: 36px;
  backdrop-filter: blur(12px); -webkit-backdrop-filter: blur(12px);
  box-shadow: var(--shadow);
}

/* ---------- feature grid ---------- */
.features {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 18px;
}
.feature {
  position: relative;
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 18px;
  padding: 26px;
  backdrop-filter: blur(12px); -webkit-backdrop-filter: blur(12px);
  transition: transform .2s ease, border-color .2s ease, background .2s ease, box-shadow .2s ease;
  overflow: hidden;
}
.feature::before {
  content: ""; position: absolute; inset: 0;
  background: radial-gradient(320px 160px at 20% 0%, rgba(94, 242, 224, 0.10), transparent 70%);
  opacity: 0; transition: opacity .25s;
}
.feature:hover {
  transform: translateY(-4px);
  background: var(--card-hover);
  border-color: var(--border-glow);
  box-shadow: 0 0 36px rgba(94, 242, 224, 0.12), 0 18px 40px rgba(0,0,0,.45);
}
.feature:hover::before { opacity: 1; }
.feature .icon {
  display: inline-grid; place-items: center;
  width: 44px; height: 44px; border-radius: 12px;
  font-size: 20px; margin-bottom: 14px;
  background: linear-gradient(135deg, rgba(94,242,224,.18), rgba(167,139,250,.18));
  border: 1px solid rgba(94, 242, 224, 0.25);
  box-shadow: 0 0 18px rgba(94, 242, 224, 0.15);
}
.feature h3 { margin: 0 0 8px; font-size: 16.5px; }
.feature p { margin: 0; color: var(--fg-muted); font-size: 14.5px; }

/* ---------- spec list ---------- */
.spec { display: grid; grid-template-columns: 190px 1fr; gap: 12px 24px; font-size: 14.5px; }
.spec dt { color: var(--fg-muted); font-family: "JetBrains Mono", ui-monospace, monospace; font-size: 12.5px; letter-spacing: .06em; text-transform: uppercase; padding-top: 2px; }
.spec dd { margin: 0; }

/* ---------- FAQ ---------- */
details { border-top: 1px solid var(--border); padding: 16px 2px; }
details:first-of-type { border-top: none; }
details > summary {
  cursor: pointer; font-weight: 600; list-style: none;
  display: flex; justify-content: space-between; align-items: center; gap: 16px;
}
details > summary::-webkit-details-marker { display: none; }
details > summary::after {
  content: "+"; color: var(--cyan); font-weight: 400; font-size: 20px;
  transition: transform .2s;
}
details[open] > summary::after { content: "–"; }
details > p, details > ul { margin-top: 10px; color: var(--fg-muted); }
details > p strong, details > ul strong { color: var(--fg); }

/* ---------- footer ---------- */
footer {
  position: relative; z-index: 2;
  text-align: center; color: var(--fg-muted); font-size: 12.5px;
  padding: 34px 16px 48px;
  border-top: 1px solid var(--border);
  margin-top: 60px;
  background: rgba(7, 6, 26, 0.4);
  backdrop-filter: blur(10px); -webkit-backdrop-filter: blur(10px);
}
footer a { color: var(--fg-muted); margin: 0 8px; }
footer a:hover { color: var(--cyan); }

/* ---------- reduced motion ---------- */
@media (prefers-reduced-motion: reduce) {
  .hero-grid, .hero-sun, .bg-stars { animation: none; }
  html { scroll-behavior: auto; }
}

/* ---------- responsive ---------- */
@media (max-width: 640px) {
  .hero { padding: 80px 20px 120px; }
  .panel { padding: 26px 22px; }
  .spec { grid-template-columns: 1fr; gap: 4px 0; }
  .spec dd { margin-bottom: 10px; }
  .topnav .links a { margin-left: 14px; font-size: 13px; }
}