/* ===== 基础变量与重置 ===== */
:root {
  --c-primary: #0EA5E9;   /* 天蓝青 主色 */
  --c-cyan: #06B6D4;      /* 青 辅色 */
  --c-ink: #0F172A;       /* 深字 */
  --c-bg-soft: #F8FAFC;   /* 浅灰底 */
  --c-line: #E2E8F0;
  --c-white: #ffffff;
  --nav-h: 64px;
  --maxw: 1120px;
  --radius: 16px;
  --shadow: 0 8px 30px rgba(15, 23, 42, 0.06);
  --font: -apple-system, "PingFang SC", "Microsoft YaHei", "Segoe UI", Roboto, sans-serif;
}

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

html { scroll-behavior: smooth; scroll-padding-top: var(--nav-h); }

body {
  font-family: var(--font);
  color: var(--c-ink);
  background: var(--c-white);
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
}

a { color: inherit; text-decoration: none; }

/* ===== 顶部导航 ===== */
.nav {
  position: fixed;
  top: 0; left: 0; right: 0;
  height: var(--nav-h);
  background: rgba(255, 255, 255, 0.82);
  backdrop-filter: saturate(180%) blur(12px);
  -webkit-backdrop-filter: saturate(180%) blur(12px);
  border-bottom: 1px solid transparent;
  z-index: 100;
  transition: box-shadow .25s ease, border-color .25s ease;
}
.nav.is-scrolled {
  box-shadow: var(--shadow);
  border-bottom-color: var(--c-line);
}
.nav__inner {
  max-width: var(--maxw);
  height: 100%;
  margin: 0 auto;
  padding: 0 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}
.nav__logo { display: flex; align-items: center; gap: 8px; }
.nav__logo-icon { display: block; }
.nav__logo-text { font-weight: 700; font-size: 19px; letter-spacing: 1px; color: var(--c-ink); }
.nav__links { display: flex; gap: 28px; }
.nav__links a {
  font-size: 15px;
  color: #334155;
  position: relative;
  padding: 4px 0;
  transition: color .2s ease;
}
.nav__links a:hover { color: var(--c-primary); }
.nav__links a::after {
  content: "";
  position: absolute; left: 0; bottom: -2px;
  width: 0; height: 2px; border-radius: 2px;
  background: linear-gradient(90deg, var(--c-primary), var(--c-cyan));
  transition: width .25s ease;
}
.nav__links a:hover::after { width: 100%; }

.nav__toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  width: 40px; height: 40px;
  background: transparent;
  border: none;
  cursor: pointer;
}
.nav__toggle span {
  display: block;
  width: 22px; height: 2px;
  background: var(--c-ink);
  border-radius: 2px;
  transition: transform .25s ease, opacity .25s ease;
}
.nav__toggle[aria-expanded="true"] span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
.nav__toggle[aria-expanded="true"] span:nth-child(2) { opacity: 0; }
.nav__toggle[aria-expanded="true"] span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }

/* ===== Hero 首屏 ===== */
.hero {
  position: relative;
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  text-align: center;
  padding: calc(var(--nav-h) + 40px) 24px 60px;
  overflow: hidden;
  background:
    radial-gradient(1200px 500px at 50% -10%, rgba(14,165,233,0.10), transparent 60%),
    var(--c-white);
}
.hero__glow {
  position: absolute;
  border-radius: 50%;
  filter: blur(70px);
  opacity: 0.5;
  pointer-events: none;
}
.hero__glow--1 {
  width: 420px; height: 420px;
  background: radial-gradient(circle, rgba(14,165,233,0.35), transparent 70%);
  top: 8%; left: -6%;
}
.hero__glow--2 {
  width: 360px; height: 360px;
  background: radial-gradient(circle, rgba(6,182,212,0.35), transparent 70%);
  bottom: 6%; right: -4%;
}
.hero__inner { position: relative; max-width: 760px; }
.hero__eyebrow {
  font-size: 14px; letter-spacing: 3px; text-transform: uppercase;
  color: var(--c-primary); font-weight: 600; margin-bottom: 18px;
}
.hero__title {
  font-size: clamp(56px, 12vw, 110px);
  font-weight: 800;
  letter-spacing: 6px;
  background: linear-gradient(135deg, var(--c-primary), var(--c-cyan));
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
  line-height: 1.05;
}
.hero__subtitle {
  font-size: clamp(18px, 3.4vw, 26px);
  font-weight: 600; color: var(--c-ink);
  margin: 22px 0 18px;
}
.hero__desc {
  font-size: 16px; color: #475569;
  max-width: 620px; margin: 0 auto 34px;
}
.hero__desc strong { color: var(--c-primary); font-weight: 700; }
.hero__cta { display: flex; gap: 16px; justify-content: center; flex-wrap: wrap; }

/* ===== 按钮 ===== */
.btn {
  display: inline-flex; align-items: center; justify-content: center;
  padding: 13px 28px;
  border-radius: 999px;
  font-size: 15px; font-weight: 600;
  cursor: pointer;
  transition: transform .15s ease, box-shadow .2s ease, background .2s ease;
  border: 1px solid transparent;
}
.btn--primary {
  background: linear-gradient(135deg, var(--c-primary), var(--c-cyan));
  color: #fff;
  box-shadow: 0 10px 24px rgba(14,165,233,0.28);
}
.btn--primary:hover { transform: translateY(-2px); box-shadow: 0 14px 30px rgba(14,165,233,0.36); }
.btn--ghost {
  background: rgba(255,255,255,0.7);
  border-color: var(--c-line);
  color: var(--c-ink);
}
.btn--ghost:hover { border-color: var(--c-primary); color: var(--c-primary); }
.btn--sm { padding: 10px 20px; font-size: 14px; margin-top: 12px; }

/* ===== 通用区块 ===== */
.section {
  max-width: var(--maxw);
  margin: 0 auto;
  padding: 96px 24px;
}
.section--alt {
  max-width: none;
  background: var(--c-bg-soft);
}
.section--alt > * { max-width: var(--maxw); margin-left: auto; margin-right: auto; }
.section__head { text-align: center; margin-bottom: 48px; }
.section__eyebrow {
  font-size: 13px; letter-spacing: 3px; text-transform: uppercase;
  color: var(--c-cyan); font-weight: 700; margin-bottom: 12px;
}
.section__title { font-size: clamp(26px, 4.4vw, 38px); font-weight: 800; letter-spacing: 1px; }
.section__lead { color: #475569; margin-top: 14px; font-size: 16px; }

/* ===== 品牌故事 ===== */
.story {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 28px;
  margin-bottom: 48px;
}
.story__col {
  background: var(--c-white);
  border: 1px solid var(--c-line);
  border-radius: var(--radius);
  padding: 28px;
}
.story__h { font-size: 19px; font-weight: 700; margin-bottom: 16px; color: var(--c-ink); }
.story__list { list-style: none; display: flex; flex-direction: column; gap: 14px; }
.story__list li { position: relative; padding-left: 22px; color: #334155; font-size: 15px; }
.story__list strong { color: var(--c-ink); }
.dot {
  position: absolute; left: 0; top: 9px;
  width: 8px; height: 8px; border-radius: 50%;
  background: linear-gradient(135deg, var(--c-primary), var(--c-cyan));
}

/* ===== 卡片网格 ===== */
.cards { display: grid; gap: 24px; }
.cards--3 { grid-template-columns: repeat(3, 1fr); }
.cards--2 { grid-template-columns: repeat(2, 1fr); }

.card {
  border-radius: var(--radius);
  padding: 28px;
  border: 1px solid rgba(226, 232, 240, 0.9);
}
.glass {
  background: rgba(255, 255, 255, 0.7);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  box-shadow: var(--shadow);
}
.card__ico { font-size: 30px; margin-bottom: 14px; }
.card__h { font-size: 18px; font-weight: 700; margin-bottom: 10px; }
.card__p { color: #475569; font-size: 15px; }
.card__meta { color: var(--c-cyan); font-size: 13px; font-weight: 600; margin-top: 10px; }

.tag {
  display: inline-block;
  font-size: 12px; font-weight: 700;
  padding: 4px 12px; border-radius: 999px;
  margin-bottom: 12px;
  color: #fff;
}
.tag--high { background: linear-gradient(135deg, #0EA5E9, #6366F1); }
.tag--daily { background: linear-gradient(135deg, #06B6D4, #0EA5E9); }
.tag--self { background: linear-gradient(135deg, #14B8A6, #06B6D4); }

/* ===== 引流钩子 ===== */
.hook { margin-top: 56px; }
.hook__h { text-align: center; font-size: 20px; font-weight: 700; margin-bottom: 24px; }
.hook__card { text-align: center; }

/* ===== 页脚 ===== */
.footer {
  background: var(--c-ink);
  color: #CBD5E1;
  padding: 40px 24px;
  text-align: center;
}
.footer__inner { max-width: var(--maxw); margin: 0 auto; }
.footer__brand { font-size: 18px; font-weight: 700; color: #fff; letter-spacing: 2px; margin-bottom: 8px; }
.footer__line { font-size: 13px; color: #94A3B8; margin-top: 4px; }

/* ===== 淡入动画 ===== */
.reveal { opacity: 0; transform: translateY(24px); transition: opacity .6s ease, transform .6s ease; }
.reveal.is-visible { opacity: 1; transform: none; }

/* ===== 响应式：768px 断点 ===== */
@media (max-width: 768px) {
  .nav__toggle { display: flex; }
  .nav__links {
    position: absolute;
    top: var(--nav-h); left: 0; right: 0;
    flex-direction: column;
    gap: 0;
    background: rgba(255,255,255,0.96);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border-bottom: 1px solid var(--c-line);
    padding: 8px 0;
    max-height: 0;
    overflow: hidden;
    transition: max-height .3s ease;
  }
  .nav__links.is-open { max-height: 280px; }
  .nav__links a { padding: 14px 24px; border-top: 1px solid var(--c-line); }

  .section { padding: 64px 20px; }
  .story { grid-template-columns: 1fr; }
  .cards--3, .cards--2 { grid-template-columns: 1fr; }
  .hero { padding-top: calc(var(--nav-h) + 24px); }
}