/* ═══════════════════════════════════════════════════════════
   慧苗官网 · 「学海行舟」
   晨航（首屏晨雾蓝）→ 白昼（功能/引擎）→ 夜航星海（下载）
   ═══════════════════════════════════════════════════════════ */

:root {
  --ink: #0a1f44;
  --mid: #3e4e77;
  --faint: #6b7aa3;
  --mist: #eaf2ff;
  --paper: #f7faff;
  --wash: #ffffff;
  --line: #dce6f7;
  --blue: #1e5eff;
  --teal: #00b4c5;
  --cta: #ff6b2c;
  --cta-deep: #e8551a;
  --green: #0e9f6e;
  --night: #0a1f44;
  --night-2: #123069;
  --display: "ZCOOL QingKe HuangYou", "Noto Sans SC", sans-serif;
  --en: "Sora", "Noto Sans SC", sans-serif;
  --body: "Noto Sans SC", sans-serif;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  background: var(--wash);
  color: var(--ink);
  font-family: var(--body);
  font-size: 17px;
  line-height: 1.6;
}
img { max-width: 100%; display: block; }
a { color: inherit; }
button { font-family: inherit; }
button, .btn, .top nav a, .phone-arrow, .phone-dots button, .feat-nav button { cursor: pointer; }

.wrap { width: min(1120px, calc(100% - 40px)); margin: 0 auto; }

.skip {
  position: absolute;
  left: 12px;
  top: -48px;
  z-index: 40;
  padding: 8px 14px;
  background: var(--ink);
  color: #fff;
  border-radius: 8px;
}
.skip:focus { top: 12px; }

/* ── 顶栏 ─────────────────────────────── */
.top {
  position: sticky;
  top: 14px;
  z-index: 20;
  display: flex;
  align-items: center;
  gap: 22px;
  width: min(1120px, calc(100% - 40px));
  margin: 14px auto 0;
  padding: 10px 18px;
  background: rgb(255 255 255 / 78%);
  backdrop-filter: blur(12px);
  border: 1px solid rgb(220 230 247 / 80%);
  border-radius: 16px;
  box-shadow: 0 10px 30px rgb(10 31 68 / 8%);
}
.brand {
  display: flex;
  align-items: center;
  gap: 9px;
  text-decoration: none;
  font-family: var(--display);
  font-size: 24px;
  letter-spacing: 0.06em;
}
.top nav { display: flex; gap: 24px; margin-left: auto; font-size: 15.5px; font-weight: 700; }
.top nav a { color: var(--mid); text-decoration: none; transition: color 180ms ease-out; }
.top nav a:hover { color: var(--blue); }

.top nav a:focus-visible, .btn:focus-visible, .feat-nav button:focus-visible,
.phone-arrow:focus-visible, .phone-dots button:focus-visible, .foot a:focus-visible {
  outline: 2px solid var(--blue);
  outline-offset: 3px;
}

/* ── 按钮 ─────────────────────────────── */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 44px;
  padding: 0 20px;
  border: 1.5px solid transparent;
  border-radius: 12px;
  font-size: 16px;
  font-weight: 800;
  text-decoration: none;
  transition: transform 180ms ease-out, box-shadow 180ms ease-out, background 180ms ease-out, color 180ms ease-out;
}
.btn-lg { min-height: 52px; padding: 0 26px; font-size: 17px; }
.btn:disabled { opacity: 0.45; cursor: not-allowed; }
.btn-accent {
  background: linear-gradient(135deg, var(--cta), var(--cta-deep));
  color: #fff;
  box-shadow: 0 10px 24px rgb(255 107 44 / 32%);
}
.btn-accent:hover:not(:disabled) { transform: translateY(-2px); box-shadow: 0 14px 30px rgb(255 107 44 / 40%); }
.btn-ghost { border-color: var(--blue); color: var(--blue); background: var(--wash); }
.btn-ghost:hover { background: var(--mist); }

/* ── 晨航：首屏 + 功能（手机右侧常驻） ── */
.voyage {
  position: relative;
  margin-top: -76px;
  padding: 140px 0 0;
  background:
    radial-gradient(720px 420px at 82% 8%, rgb(0 180 197 / 14%), transparent 68%),
    radial-gradient(900px 520px at 8% 30%, rgb(30 94 255 / 10%), transparent 70%),
    linear-gradient(180deg, var(--mist) 0%, #f4f9ff 48%, #fdfeff 100%);
}
.stage {
  display: grid;
  grid-template-areas:
    "hero phone"
    "features phone";
  grid-template-columns: minmax(0, 1fr) 280px;
  grid-template-rows: auto 1fr;
  gap: 26px 48px;
  align-items: start;
  padding-bottom: 130px;
}
.hero-copy { grid-area: hero; }
.phone-show { grid-area: phone; }
.features-block { grid-area: features; padding-top: 26px; }
.kicker {
  margin: 0;
  font-family: var(--en);
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0.22em;
  text-transform: uppercase;
  color: var(--teal);
}
.hero-copy h1 {
  margin: 14px 0 0;
  font-family: var(--display);
  font-weight: 400;
  font-size: clamp(46px, 6.4vw, 78px);
  line-height: 1.12;
  letter-spacing: 0.03em;
}
.hero-copy h1 em {
  font-style: normal;
  background: linear-gradient(120deg, var(--blue) 20%, var(--teal) 95%);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}
.sub { margin: 18px 0 0; max-width: 46ch; font-size: 18px; color: var(--mid); }
.hero-actions { display: flex; flex-wrap: wrap; gap: 12px; margin-top: 26px; }
.hero-ver { margin: 12px 0 0; font-size: 14px; color: var(--faint); }

.hero-facts {
  display: flex;
  gap: 34px;
  margin: 30px 0 0;
  padding: 18px 0 0;
  border-top: 1px solid rgb(30 94 255 / 14%);
}
.hero-facts div { display: flex; flex-direction: column; }
.hero-facts dt { font-family: var(--en); font-size: 21px; font-weight: 800; color: var(--ink); }
.hero-facts dd { margin: 2px 0 0; font-size: 13.5px; color: var(--faint); }

/* 波浪分隔 + 小船 */
.wave { position: absolute; left: 0; right: 0; bottom: -1px; pointer-events: none; }
.wave svg { display: block; width: 100%; height: 96px; }
.boat { animation: sail 9s ease-in-out infinite; transform-origin: center; }
@keyframes sail {
  0%, 100% { transform: translate(0, 0) rotate(0deg); }
  50% { transform: translate(-16px, 4px) rotate(-2deg); }
}

/* 入场动效 */
.rise { opacity: 0; transform: translateY(18px); animation: rise 640ms cubic-bezier(0.22, 0.9, 0.3, 1) forwards; }
.r1 { animation-delay: 60ms; }
.r2 { animation-delay: 160ms; }
.r3 { animation-delay: 280ms; }
.r4 { animation-delay: 400ms; }
.r5 { animation-delay: 520ms; }
@keyframes rise { to { opacity: 1; transform: none; } }

.reveal { opacity: 0; transform: translateY(22px); transition: opacity 560ms ease-out, transform 560ms cubic-bezier(0.22, 0.9, 0.3, 1); }
.reveal.in { opacity: 1; transform: none; }

/* ── 手机轮播 ─────────────────────────── */
.phone-show {
  position: sticky;
  top: 86px;
  z-index: 2;
  margin: 0;
}
.phone {
  position: relative;
  width: 100%;
  aspect-ratio: 9 / 19;
  padding: 10px 8px 12px;
  background: #101c38;
  border-radius: 34px;
  border: 1px solid #0a1f44;
  box-shadow:
    0 30px 60px rgb(10 31 68 / 26%),
    0 4px 14px rgb(10 31 68 / 18%);
  overflow: hidden;
}
.phone-notch {
  position: absolute;
  top: 11px;
  left: 50%;
  z-index: 2;
  width: 74px;
  height: 10px;
  margin-left: -37px;
  background: #050e22;
  border-radius: 6px;
}
.phone-view { height: 100%; overflow: hidden; border-radius: 24px; background: #fff; }
.phone-track { display: flex; height: 100%; transition: transform 300ms ease-out; }
.slide { flex: 0 0 100%; height: 100%; min-width: 0; }
.slide img { width: 100%; height: 100%; object-fit: cover; }

.phone-ui { display: flex; align-items: center; justify-content: space-between; gap: 8px; margin-top: 12px; }
.phone-ui p { margin: 0; font-family: var(--en); font-size: 14px; font-weight: 700; color: var(--ink); }
.phone-arrow {
  width: 38px;
  height: 38px;
  border: 1px solid var(--line);
  border-radius: 12px;
  background: var(--wash);
  color: var(--blue);
  font-size: 22px;
  line-height: 1;
  transition: background 180ms ease-out, transform 180ms ease-out;
}
.phone-arrow:hover { background: var(--mist); transform: translateY(-1px); }
.phone-dots { display: flex; justify-content: center; gap: 7px; margin-top: 10px; }
.phone-dots button {
  width: 8px;
  height: 8px;
  padding: 0;
  border: 0;
  border-radius: 50%;
  background: var(--line);
  transition: background 180ms ease-out, transform 180ms ease-out;
}
.phone-dots button.on { background: var(--blue); transform: scale(1.25); }

/* ── 章节标题 ─────────────────────────── */
.sec-head { max-width: 60ch; }
.sec-head h2 {
  margin: 10px 0 0;
  font-family: var(--display);
  font-weight: 400;
  font-size: clamp(30px, 3.6vw, 44px);
  letter-spacing: 0.02em;
}
.sec-sub { margin: 10px 0 0; color: var(--mid); font-size: 17px; }

/* ── 功能区 ───────────────────────────── */
.feat {
  display: grid;
  grid-template-columns: 236px minmax(0, 1fr);
  gap: 30px;
  margin-top: 24px;
  padding: 24px 26px;
  background: rgb(255 255 255 / 82%);
  border: 1px solid var(--line);
  border-radius: 22px;
  box-shadow: 0 14px 36px rgb(10 31 68 / 7%);
}
.feat-nav { display: flex; flex-direction: column; gap: 2px; }
.feat-nav button {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 10px 12px;
  border: 0;
  border-radius: 12px;
  background: none;
  text-align: left;
  font-size: 16.5px;
  font-weight: 800;
  color: var(--mid);
  transition: background 180ms ease-out, color 180ms ease-out;
}
.feat-nav button b {
  font-family: var(--en);
  font-size: 12px;
  font-weight: 700;
  color: var(--faint);
  transition: color 180ms ease-out;
}
.feat-nav button:hover { background: rgb(30 94 255 / 6%); color: var(--ink); }
.feat-nav button.on { background: var(--wash); color: var(--blue); box-shadow: 0 6px 16px rgb(10 31 68 / 8%); }
.feat-nav button.on b { color: var(--teal); }
.feat-tab {
  margin: 4px 0 0;
  font-family: var(--en);
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0.1em;
  color: var(--teal);
}
.feat-stage h3 {
  margin: 8px 0 10px;
  font-family: var(--display);
  font-weight: 400;
  font-size: clamp(24px, 2.6vw, 32px);
}
.feat-stage > p { margin: 0; max-width: 44ch; font-size: 17px; color: var(--mid); }

/* ── 科技底座 ─────────────────────────── */
.tech { padding: 56px 0 72px; background: var(--wash); }
.tech-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
  margin-top: 30px;
}
.tech-card {
  position: relative;
  padding: 26px 24px 24px;
  background: var(--wash);
  border: 1px solid var(--line);
  border-radius: 18px;
  overflow: hidden;
  transition: transform 200ms ease-out, box-shadow 200ms ease-out;
}
.tech-card::before {
  content: "";
  position: absolute;
  inset: 0 auto auto 0;
  width: 100%;
  height: 4px;
  background: linear-gradient(90deg, var(--blue), var(--teal));
}
.tech-card:hover { transform: translateY(-5px); box-shadow: 0 18px 40px rgb(10 31 68 / 12%); }
.tech-no { margin: 0; font-family: var(--en); font-size: 12px; font-weight: 700; letter-spacing: 0.16em; color: var(--teal); text-transform: uppercase; }
.tech-card h3 { margin: 10px 0 8px; font-family: var(--display); font-weight: 400; font-size: 26px; }
.tech-card p:last-child { margin: 0; color: var(--mid); font-size: 15.5px; }

/* ── 下载 · 夜航星海 ──────────────────── */
.release {
  position: relative;
  padding: 76px 0 88px;
  color: #e8efff;
  background:
    radial-gradient(2px 2px at 12% 24%, rgb(255 255 255 / 85%), transparent 100%),
    radial-gradient(1.5px 1.5px at 28% 62%, rgb(255 255 255 / 60%), transparent 100%),
    radial-gradient(2px 2px at 44% 18%, rgb(160 200 255 / 80%), transparent 100%),
    radial-gradient(1.5px 1.5px at 58% 48%, rgb(255 255 255 / 55%), transparent 100%),
    radial-gradient(2px 2px at 72% 28%, rgb(255 255 255 / 75%), transparent 100%),
    radial-gradient(1.5px 1.5px at 86% 58%, rgb(160 220 255 / 70%), transparent 100%),
    radial-gradient(2.5px 2.5px at 92% 14%, rgb(255 255 255 / 85%), transparent 100%),
    radial-gradient(1200px 500px at 50% 120%, var(--night-2), transparent 75%),
    linear-gradient(180deg, var(--night) 0%, #0d2554 100%);
}
.release .kicker { color: #63d8e4; }
.release .sec-head h2 { color: #fff; }
.release .sec-sub { color: #a9bce6; }
.dl {
  display: grid;
  grid-template-columns: minmax(0, 1.1fr) minmax(0, 0.9fr);
  gap: 36px;
  margin-top: 30px;
  padding: 30px 32px;
  background: rgb(255 255 255 / 97%);
  border-radius: 22px;
  color: var(--ink);
  box-shadow: 0 30px 70px rgb(2 10 30 / 45%);
}
.dl-os { margin: 0; font-family: var(--en); font-size: 12px; font-weight: 700; letter-spacing: 0.16em; color: var(--teal); text-transform: uppercase; }
.dl h3 { margin: 6px 0 2px; font-family: var(--display); font-weight: 400; font-size: 34px; }
.dl-meta { margin: 0 0 6px; color: var(--cta-deep); font-weight: 800; }
.dl-notes { margin: 0 0 16px; color: var(--mid); font-size: 15.5px; }
.dl-hint { min-height: 1.2em; margin: 10px 0 0; font-size: 14.5px; color: var(--mid); }
.dl-side { padding-left: 28px; border-left: 1px solid var(--line); color: var(--mid); font-size: 15.5px; }
.dl-qr { margin-bottom: 16px; text-align: center; }
.dl-qr-label { margin: 0 0 8px; font-size: 13px; font-weight: 700; color: var(--ink); }
.dl-qr img { display: block; margin: 0 auto; border-radius: 12px; border: 1px solid var(--line); }
.dl-side > p { margin: 0 0 8px; }
.dl-side b { color: var(--ink); }
.install { margin: 14px 0 0; padding-left: 18px; color: var(--faint); font-size: 14px; }
.install li + li { margin-top: 5px; }

/* ── 页脚 ─────────────────────────────── */
.foot { background: #071838; color: #8fa3cf; font-size: 14.5px; }
.foot-grid {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 18px 40px;
  padding: 26px 0;
}
.foot-brand { margin: 0 0 2px; font-family: var(--display); font-size: 22px; color: #fff; letter-spacing: 0.06em; }
.foot-grid > div > p { margin: 0; }
.foot-links { display: flex; gap: 22px; margin-left: auto; }
.foot a { color: #b9c8ea; text-decoration: none; transition: color 180ms ease-out; }
.foot a:hover { color: #fff; }
.copy { margin: 0; font-size: 13px; width: 100%; }
.foot-beian { display: flex; flex-wrap: wrap; gap: 6px 20px; padding-bottom: 20px; }
.foot-beian a { color: #8fa3cf; }

/* ── 隐私页 ───────────────────────────── */
.legal-doc { max-width: 70ch; padding: 40px 0 72px; }
.legal-doc h1 { font-family: var(--display); font-weight: 400; font-size: 36px; }
.legal-doc h2 { margin: 24px 0 6px; font-size: 21px; }
.legal-lead, .legal-doc p { color: var(--mid); }
.back { margin-top: 28px; font-weight: 800; }
.back a { color: var(--cta-deep); }

/* ── Toast ────────────────────────────── */
.toast {
  position: fixed;
  left: 50%;
  bottom: 22px;
  z-index: 30;
  transform: translateX(-50%);
  max-width: min(88vw, 480px);
  padding: 11px 16px;
  background: var(--ink);
  color: #fff;
  font-weight: 700;
  font-size: 15px;
  border-radius: 12px;
  box-shadow: 0 14px 34px rgb(10 31 68 / 35%);
}

/* ── 响应式 ───────────────────────────── */
@media (max-width: 920px) {
  .top nav { display: none; }
  .voyage { margin-top: -70px; padding-top: 118px; }
  .stage {
    grid-template-areas: "hero" "phone" "features";
    grid-template-columns: 1fr;
    grid-template-rows: none;
    gap: 40px;
    padding-bottom: 96px;
  }
  .phone-show { position: static; width: min(70vw, 280px); margin: 0 auto; }
  .features-block { padding-top: 0; }
  .hero-facts { gap: 22px; flex-wrap: wrap; }
  .feat { grid-template-columns: 1fr; gap: 20px; }
  .feat-nav { flex-direction: row; flex-wrap: wrap; }
  .feat-nav button { padding: 8px 12px; }
  .tech-grid { grid-template-columns: 1fr; }
  .dl { grid-template-columns: 1fr; gap: 24px; }
  .dl-side { padding-left: 0; border-left: 0; border-top: 1px solid var(--line); padding-top: 18px; }
  .foot-links { margin-left: 0; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { animation: none !important; transition: none !important; }
  .rise, .reveal { opacity: 1; transform: none; }
}