/* ==========================================================================
   良票网络 官网样式表
   零依赖 / 零构建，可直接部署到对象存储
   ========================================================================== */

/* ---------- 1. 设计变量 ---------- */
:root {
  --c-primary: #2b5cff;
  --c-primary-dark: #1a3ec4;
  --c-primary-soft: #eaf0ff;
  --c-accent: #00c2a8;
  --c-accent-soft: #e2fbf6;

  --c-ink: #0d1220;
  --c-text: #2c3444;
  --c-muted: #6b7488;
  --c-line: #e6e9f0;
  --c-bg: #ffffff;
  --c-bg-soft: #f6f8fc;
  --c-dark: #0b1020;

  --radius-s: 8px;
  --radius-m: 14px;
  --radius-l: 22px;

  --shadow-s: 0 1px 2px rgba(13, 18, 32, .05), 0 4px 12px rgba(13, 18, 32, .05);
  --shadow-m: 0 2px 6px rgba(13, 18, 32, .06), 0 16px 40px rgba(13, 18, 32, .08);
  --shadow-brand: 0 10px 30px rgba(43, 92, 255, .25);

  --container: 1180px;
  --header-h: 68px;

  --ease: cubic-bezier(.22, .68, .32, 1);
}

/* ---------- 2. 基础重置 ---------- */
*, *::before, *::after { box-sizing: border-box; }

html {
  -webkit-text-size-adjust: 100%;
  scroll-behavior: smooth;
  scroll-padding-top: calc(var(--header-h) + 20px);
}

body {
  margin: 0;
  font-family: "PingFang SC", "HarmonyOS Sans SC", "Microsoft YaHei",
    -apple-system, BlinkMacSystemFont, "Segoe UI", "Noto Sans SC", Roboto,
    "Helvetica Neue", Arial, sans-serif;
  font-size: 16px;
  line-height: 1.75;
  color: var(--c-text);
  background: var(--c-bg);
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

img, svg { max-width: 100%; display: block; }
a { color: inherit; text-decoration: none; }
ul, ol { margin: 0; padding: 0; list-style: none; }

h1, h2, h3, h4 {
  margin: 0;
  color: var(--c-ink);
  line-height: 1.3;
  font-weight: 700;
  letter-spacing: -.01em;
}

p { margin: 0; }

/* ---------- 3. 布局工具 ---------- */
.container {
  width: 100%;
  max-width: var(--container);
  margin-inline: auto;
  padding-inline: 24px;
}

.section { padding: 92px 0; }
.section--soft { background: var(--c-bg-soft); }
.section--tight { padding: 64px 0; }

.section-head {
  max-width: 720px;
  margin: 0 auto 56px;
  text-align: center;
}

.section-head--left {
  margin-inline: 0;
  text-align: left;
}

.eyebrow {
  display: inline-block;
  margin-bottom: 14px;
  padding: 5px 14px;
  border-radius: 999px;
  background: var(--c-primary-soft);
  color: var(--c-primary-dark);
  font-size: 13px;
  font-weight: 600;
  letter-spacing: .04em;
}

.section-title {
  font-size: clamp(26px, 3.4vw, 38px);
  margin-bottom: 16px;
}

.section-desc {
  color: var(--c-muted);
  font-size: 16.5px;
}

.grid { display: grid; gap: 24px; }
.grid--2 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
.grid--3 { grid-template-columns: repeat(3, minmax(0, 1fr)); }
.grid--4 { grid-template-columns: repeat(4, minmax(0, 1fr)); }

/* ---------- 4. 按钮 ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 13px 26px;
  border: 1px solid transparent;
  border-radius: 999px;
  font-size: 15px;
  font-weight: 600;
  cursor: pointer;
  transition: transform .2s var(--ease), box-shadow .2s var(--ease),
    background-color .2s var(--ease), color .2s var(--ease),
    border-color .2s var(--ease);
  white-space: nowrap;
}

.btn:hover { transform: translateY(-2px); }
.btn:active { transform: translateY(0); }

.btn--primary {
  background: var(--c-primary);
  color: #fff;
  box-shadow: var(--shadow-brand);
}
.btn--primary:hover { background: var(--c-primary-dark); }

.btn--ghost {
  background: #fff;
  color: var(--c-ink);
  border-color: var(--c-line);
  box-shadow: var(--shadow-s);
}
.btn--ghost:hover { border-color: var(--c-primary); color: var(--c-primary); }

.btn--light {
  background: rgba(255, 255, 255, .12);
  color: #fff;
  border-color: rgba(255, 255, 255, .3);
  backdrop-filter: blur(6px);
}
.btn--light:hover { background: rgba(255, 255, 255, .22); }

.btn--sm { padding: 9px 20px; font-size: 14px; }

.link-arrow {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  color: var(--c-primary);
  font-weight: 600;
  font-size: 15px;
}
.link-arrow svg { transition: transform .2s var(--ease); }
.link-arrow:hover svg { transform: translateX(4px); }

/* ---------- 5. 页头导航 ---------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  height: var(--header-h);
  background: rgba(255, 255, 255, .82);
  backdrop-filter: saturate(180%) blur(14px);
  -webkit-backdrop-filter: saturate(180%) blur(14px);
  border-bottom: 1px solid transparent;
  transition: border-color .25s var(--ease), box-shadow .25s var(--ease);
}
.site-header.is-scrolled {
  border-bottom-color: var(--c-line);
  box-shadow: 0 4px 20px rgba(13, 18, 32, .05);
}

.site-header__inner {
  height: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-weight: 700;
  font-size: 19px;
  color: var(--c-ink);
  letter-spacing: -.01em;
}
.brand__mark { width: 32px; height: 32px; flex: none; }
.brand__sub {
  font-size: 12px;
  font-weight: 500;
  color: var(--c-muted);
  letter-spacing: .12em;
  text-transform: uppercase;
  padding-left: 10px;
  margin-left: 2px;
  border-left: 1px solid var(--c-line);
}

.nav { display: flex; align-items: center; gap: 6px; }

.nav__link {
  position: relative;
  padding: 8px 14px;
  border-radius: var(--radius-s);
  font-size: 15px;
  font-weight: 500;
  color: var(--c-text);
  transition: color .2s var(--ease), background-color .2s var(--ease);
}
.nav__link:hover { color: var(--c-primary); background: var(--c-primary-soft); }
.nav__link.is-active { color: var(--c-primary); font-weight: 600; }

.header-actions { display: flex; align-items: center; gap: 12px; }

.nav-toggle {
  display: none;
  width: 42px;
  height: 42px;
  padding: 0;
  border: 1px solid var(--c-line);
  border-radius: var(--radius-s);
  background: #fff;
  cursor: pointer;
  align-items: center;
  justify-content: center;
}
.nav-toggle span {
  position: relative;
  display: block;
  width: 18px;
  height: 2px;
  border-radius: 2px;
  background: var(--c-ink);
  transition: background-color .2s var(--ease);
}
.nav-toggle span::before,
.nav-toggle span::after {
  content: "";
  position: absolute;
  left: 0;
  width: 18px;
  height: 2px;
  border-radius: 2px;
  background: var(--c-ink);
  transition: transform .25s var(--ease);
}
.nav-toggle span::before { top: -6px; }
.nav-toggle span::after { top: 6px; }

.nav-toggle[aria-expanded="true"] span { background: transparent; }
.nav-toggle[aria-expanded="true"] span::before { transform: translateY(6px) rotate(45deg); }
.nav-toggle[aria-expanded="true"] span::after { transform: translateY(-6px) rotate(-45deg); }

/* ---------- 6. 首屏 Hero ---------- */
.hero {
  position: relative;
  overflow: hidden;
  padding: 104px 0 96px;
  background: var(--c-dark);
  color: #fff;
}

.hero::before,
.hero::after {
  content: "";
  position: absolute;
  border-radius: 50%;
  filter: blur(90px);
  opacity: .5;
  pointer-events: none;
}
.hero::before {
  width: 560px; height: 560px;
  top: -220px; left: -140px;
  background: radial-gradient(circle, #2b5cff 0%, transparent 70%);
}
.hero::after {
  width: 620px; height: 620px;
  right: -200px; bottom: -300px;
  background: radial-gradient(circle, #00c2a8 0%, transparent 70%);
  opacity: .35;
}

.hero__grid {
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(255, 255, 255, .05) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255, 255, 255, .05) 1px, transparent 1px);
  background-size: 56px 56px;
  mask-image: radial-gradient(ellipse 80% 60% at 50% 30%, #000 30%, transparent 78%);
  -webkit-mask-image: radial-gradient(ellipse 80% 60% at 50% 30%, #000 30%, transparent 78%);
  pointer-events: none;
}

.hero__inner {
  position: relative;
  z-index: 1;
  display: grid;
  grid-template-columns: 1.05fr .95fr;
  gap: 56px;
  align-items: center;
}

.hero__badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  margin-bottom: 22px;
  padding: 6px 16px 6px 8px;
  border-radius: 999px;
  background: rgba(255, 255, 255, .08);
  border: 1px solid rgba(255, 255, 255, .16);
  font-size: 13.5px;
  color: rgba(255, 255, 255, .88);
}
.hero__badge b {
  padding: 2px 9px;
  border-radius: 999px;
  background: var(--c-accent);
  color: #04231f;
  font-size: 12px;
  font-weight: 700;
}

.hero__title {
  font-size: clamp(34px, 4.8vw, 56px);
  line-height: 1.18;
  color: #fff;
  margin-bottom: 22px;
  letter-spacing: -.02em;
}
.hero__title em {
  font-style: normal;
  background: linear-gradient(100deg, #7aa2ff 0%, #38e5c8 100%);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}

.hero__desc {
  max-width: 540px;
  font-size: 17px;
  line-height: 1.85;
  color: rgba(255, 255, 255, .7);
  margin-bottom: 34px;
}

.hero__actions { display: flex; flex-wrap: wrap; gap: 14px; margin-bottom: 44px; }

.hero__stats {
  display: flex;
  flex-wrap: wrap;
  gap: 40px;
  padding-top: 30px;
  border-top: 1px solid rgba(255, 255, 255, .12);
}
.hero__stat b {
  display: block;
  font-size: 30px;
  font-weight: 700;
  color: #fff;
  line-height: 1.2;
  letter-spacing: -.02em;
}
.hero__stat span { font-size: 14px; color: rgba(255, 255, 255, .58); }

/* Hero 右侧产品矩阵卡 */
.hero__panel {
  position: relative;
  padding: 22px;
  border-radius: var(--radius-l);
  background: rgba(255, 255, 255, .06);
  border: 1px solid rgba(255, 255, 255, .12);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  box-shadow: 0 30px 70px rgba(0, 0, 0, .4);
}

.hero__panel-head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 18px;
  padding-bottom: 14px;
  border-bottom: 1px solid rgba(255, 255, 255, .1);
  font-size: 13.5px;
  color: rgba(255, 255, 255, .6);
}
.dot-group { display: flex; gap: 6px; }
.dot-group i {
  width: 9px; height: 9px;
  border-radius: 50%;
  background: rgba(255, 255, 255, .22);
}
.dot-group i:first-child { background: #ff6b6b; }
.dot-group i:nth-child(2) { background: #ffbe4d; }
.dot-group i:nth-child(3) { background: #35d39a; }

.stack-item {
  display: flex;
  align-items: center;
  gap: 14px;
  padding: 14px;
  border-radius: var(--radius-m);
  background: rgba(255, 255, 255, .05);
  border: 1px solid rgba(255, 255, 255, .08);
  transition: transform .25s var(--ease), background-color .25s var(--ease);
}
.stack-item + .stack-item { margin-top: 10px; }
.stack-item:hover {
  transform: translateX(6px);
  background: rgba(255, 255, 255, .1);
}
.stack-item__icon {
  width: 40px; height: 40px;
  flex: none;
  display: grid;
  place-items: center;
  border-radius: 11px;
  background: linear-gradient(135deg, rgba(122, 162, 255, .3), rgba(56, 229, 200, .25));
  color: #cfe0ff;
}
.stack-item__icon svg { width: 20px; height: 20px; }
.stack-item h4 { color: #fff; font-size: 15.5px; margin-bottom: 2px; }
.stack-item p { font-size: 13px; color: rgba(255, 255, 255, .55); line-height: 1.5; }
.stack-item__tag {
  margin-left: auto;
  flex: none;
  padding: 3px 10px;
  border-radius: 999px;
  background: rgba(56, 229, 200, .16);
  color: #38e5c8;
  font-size: 12px;
  font-weight: 600;
}

.hero__flow {
  margin-top: 16px;
  padding: 14px;
  border-radius: var(--radius-m);
  background: rgba(0, 0, 0, .22);
  border: 1px dashed rgba(255, 255, 255, .16);
}
.hero__flow span { font-size: 12px; color: rgba(255, 255, 255, .45); letter-spacing: .06em; }
.hero__flow p {
  margin-top: 6px;
  font-size: 13.5px;
  color: rgba(255, 255, 255, .82);
  line-height: 1.7;
}

/* ---------- 7. 页面小 Banner（内页顶部） ---------- */
.page-hero {
  position: relative;
  overflow: hidden;
  padding: 76px 0 68px;
  background: linear-gradient(160deg, #0b1020 0%, #16255c 100%);
  color: #fff;
}
.page-hero::after {
  content: "";
  position: absolute;
  width: 520px; height: 520px;
  right: -160px; top: -220px;
  border-radius: 50%;
  background: radial-gradient(circle, rgba(0, 194, 168, .5) 0%, transparent 70%);
  filter: blur(80px);
}
.page-hero__inner { position: relative; z-index: 1; max-width: 760px; }
.page-hero h1 {
  color: #fff;
  font-size: clamp(28px, 4vw, 42px);
  margin-bottom: 16px;
}
.page-hero p {
  font-size: 17px;
  color: rgba(255, 255, 255, .72);
  line-height: 1.85;
}

.breadcrumb {
  display: flex;
  align-items: center;
  gap: 8px;
  margin-bottom: 18px;
  font-size: 13.5px;
  color: rgba(255, 255, 255, .55);
}
.breadcrumb a:hover { color: #fff; }

/* ---------- 8. 通用卡片 ---------- */
.card {
  padding: 30px;
  border-radius: var(--radius-l);
  background: #fff;
  border: 1px solid var(--c-line);
  transition: transform .28s var(--ease), box-shadow .28s var(--ease),
    border-color .28s var(--ease);
}
.card:hover {
  transform: translateY(-5px);
  box-shadow: var(--shadow-m);
  border-color: rgba(43, 92, 255, .28);
}
.card__icon {
  width: 50px; height: 50px;
  display: grid;
  place-items: center;
  margin-bottom: 18px;
  border-radius: 14px;
  background: var(--c-primary-soft);
  color: var(--c-primary);
}
.card__icon--accent { background: var(--c-accent-soft); color: #00a08b; }
.card__icon svg { width: 24px; height: 24px; }
.card h3 { font-size: 19px; margin-bottom: 10px; }
.card p { color: var(--c-muted); font-size: 15px; line-height: 1.8; }

/* 产品卡（大） */
.product-card {
  display: grid;
  grid-template-columns: 1fr;
  gap: 0;
  overflow: hidden;
  border-radius: var(--radius-l);
  border: 1px solid var(--c-line);
  background: #fff;
  transition: box-shadow .3s var(--ease), border-color .3s var(--ease);
}
.product-card:hover {
  box-shadow: var(--shadow-m);
  border-color: rgba(43, 92, 255, .28);
}
.product-card__body { padding: 34px; }
.product-card__top {
  display: flex;
  align-items: center;
  gap: 14px;
  margin-bottom: 18px;
}
.product-card__logo {
  width: 52px; height: 52px;
  flex: none;
  display: grid;
  place-items: center;
  border-radius: 15px;
  color: #fff;
  background: linear-gradient(135deg, var(--c-primary), #5b86ff);
  box-shadow: 0 8px 20px rgba(43, 92, 255, .28);
}
.product-card__logo--teal {
  background: linear-gradient(135deg, #00b39c, #3ad6bd);
  box-shadow: 0 8px 20px rgba(0, 179, 156, .28);
}
.product-card__logo--violet {
  background: linear-gradient(135deg, #6d5bff, #9d8bff);
  box-shadow: 0 8px 20px rgba(109, 91, 255, .28);
}
.product-card__logo svg { width: 26px; height: 26px; }
.product-card h3 { font-size: 21px; }
.product-card__role { font-size: 13.5px; color: var(--c-muted); }
.product-card > .product-card__body > p { color: var(--c-muted); font-size: 15px; }

.feature-list { margin: 20px 0 24px; }
.feature-list li {
  position: relative;
  padding-left: 26px;
  margin-bottom: 10px;
  font-size: 15px;
  color: var(--c-text);
}
.feature-list li::before {
  content: "";
  position: absolute;
  left: 0; top: 9px;
  width: 16px; height: 16px;
  border-radius: 50%;
  background: var(--c-primary-soft) url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24' fill='none' stroke='%232b5cff' stroke-width='3.4' stroke-linecap='round' stroke-linejoin='round'%3E%3Cpolyline points='20 6 9 17 4 12'/%3E%3C/svg%3E") center / 10px no-repeat;
}

.tag-row { display: flex; flex-wrap: wrap; gap: 8px; }
.tag {
  padding: 5px 13px;
  border-radius: 999px;
  background: var(--c-bg-soft);
  border: 1px solid var(--c-line);
  font-size: 13px;
  color: var(--c-muted);
}
.tag--on {
  background: var(--c-accent-soft);
  border-color: rgba(0, 194, 168, .3);
  color: #00806f;
  font-weight: 600;
}

/* ---------- 9. 图文交错模块 ---------- */
.split {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 60px;
  align-items: center;
}
.split + .split { margin-top: 90px; }
.split--reverse .split__media { order: -1; }

.split__title { font-size: clamp(23px, 2.6vw, 30px); margin-bottom: 16px; }
.split__desc { color: var(--c-muted); font-size: 16px; margin-bottom: 24px; }

.split__media {
  position: relative;
  padding: 26px;
  border-radius: var(--radius-l);
  background: linear-gradient(150deg, #f0f4ff 0%, #e6fbf7 100%);
  border: 1px solid var(--c-line);
}

/* 流程图 */
.flow { display: grid; gap: 12px; }
.flow__step {
  display: flex;
  align-items: center;
  gap: 14px;
  padding: 15px 18px;
  border-radius: var(--radius-m);
  background: #fff;
  box-shadow: var(--shadow-s);
}
.flow__num {
  width: 28px; height: 28px;
  flex: none;
  display: grid;
  place-items: center;
  border-radius: 50%;
  background: var(--c-primary);
  color: #fff;
  font-size: 13px;
  font-weight: 700;
}
.flow__step b { display: block; font-size: 15px; color: var(--c-ink); }
.flow__step span { font-size: 13px; color: var(--c-muted); }
.flow__arrow {
  justify-self: center;
  width: 18px; height: 18px;
  color: var(--c-primary);
  opacity: .5;
}

/* ---------- 10. 数据条 ---------- */
.stat-band {
  padding: 44px 0;
  background: linear-gradient(120deg, var(--c-primary) 0%, #4b7bff 55%, #00b39c 130%);
  color: #fff;
}
.stat-band__grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 20px;
  text-align: center;
}
.stat-band b {
  display: block;
  font-size: clamp(26px, 3vw, 34px);
  font-weight: 700;
  letter-spacing: -.02em;
}
.stat-band span { font-size: 14px; color: rgba(255, 255, 255, .78); }

/* ---------- 11. 时间轴 ---------- */
.timeline { position: relative; padding-left: 30px; }
.timeline::before {
  content: "";
  position: absolute;
  left: 5px; top: 8px; bottom: 8px;
  width: 2px;
  background: linear-gradient(180deg, var(--c-primary), var(--c-accent));
  opacity: .3;
}
.timeline__item { position: relative; padding-bottom: 30px; }
.timeline__item::before {
  content: "";
  position: absolute;
  left: -30px; top: 8px;
  width: 12px; height: 12px;
  border-radius: 50%;
  background: #fff;
  border: 3px solid var(--c-primary);
}
.timeline__year {
  font-size: 14px;
  font-weight: 700;
  color: var(--c-primary);
  letter-spacing: .04em;
}
.timeline__item h4 { font-size: 17px; margin: 4px 0 6px; }
.timeline__item p { color: var(--c-muted); font-size: 15px; }

/* ---------- 12. 联系页 ---------- */
.contact-grid {
  display: grid;
  grid-template-columns: 1.1fr .9fr;
  gap: 40px;
  align-items: start;
}

.contact-item {
  display: flex;
  gap: 16px;
  padding: 24px;
  border-radius: var(--radius-m);
  border: 1px solid var(--c-line);
  background: #fff;
  transition: border-color .25s var(--ease), box-shadow .25s var(--ease);
}
.contact-item + .contact-item { margin-top: 16px; }
.contact-item:hover { border-color: rgba(43, 92, 255, .3); box-shadow: var(--shadow-s); }
.contact-item__icon {
  width: 44px; height: 44px;
  flex: none;
  display: grid;
  place-items: center;
  border-radius: 12px;
  background: var(--c-primary-soft);
  color: var(--c-primary);
}
.contact-item__icon svg { width: 21px; height: 21px; }
.contact-item h4 { font-size: 16px; margin-bottom: 4px; }
.contact-item p { font-size: 15px; color: var(--c-muted); word-break: break-all; }
.contact-item a:hover { color: var(--c-primary); }

.panel {
  padding: 32px;
  border-radius: var(--radius-l);
  background: var(--c-bg-soft);
  border: 1px solid var(--c-line);
}
.panel h3 { font-size: 19px; margin-bottom: 8px; }
.panel > p { color: var(--c-muted); font-size: 15px; margin-bottom: 22px; }

.field { margin-bottom: 16px; }
.field label {
  display: block;
  margin-bottom: 7px;
  font-size: 14px;
  font-weight: 600;
  color: var(--c-ink);
}
.field input,
.field textarea,
.field select {
  width: 100%;
  padding: 12px 14px;
  border: 1px solid var(--c-line);
  border-radius: var(--radius-s);
  background: #fff;
  font-family: inherit;
  font-size: 15px;
  color: var(--c-text);
  transition: border-color .2s var(--ease), box-shadow .2s var(--ease);
}
.field textarea { min-height: 110px; resize: vertical; }
.field input:focus,
.field textarea:focus,
.field select:focus {
  outline: none;
  border-color: var(--c-primary);
  box-shadow: 0 0 0 3px rgba(43, 92, 255, .12);
}

.form-note {
  margin-top: 14px;
  font-size: 13px;
  color: var(--c-muted);
  line-height: 1.7;
}

.form-status {
  margin-top: 14px;
  padding: 12px 14px;
  border-radius: var(--radius-s);
  background: var(--c-accent-soft);
  border: 1px solid rgba(0, 194, 168, .3);
  color: #00705f;
  font-size: 14px;
}
.form-status[hidden] { display: none; }

/* ---------- 13. FAQ 折叠 ---------- */
.faq-item {
  border: 1px solid var(--c-line);
  border-radius: var(--radius-m);
  background: #fff;
  overflow: hidden;
}
.faq-item + .faq-item { margin-top: 12px; }
.faq-item summary {
  padding: 20px 24px;
  font-size: 16.5px;
  font-weight: 600;
  color: var(--c-ink);
  cursor: pointer;
  list-style: none;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
}
.faq-item summary::-webkit-details-marker { display: none; }
.faq-item summary::after {
  content: "";
  width: 10px; height: 10px;
  flex: none;
  border-right: 2px solid var(--c-muted);
  border-bottom: 2px solid var(--c-muted);
  transform: rotate(45deg) translateY(-3px);
  transition: transform .25s var(--ease);
}
.faq-item[open] summary::after { transform: rotate(-135deg) translateY(-3px); }
.faq-item__body {
  padding: 0 24px 22px;
  color: var(--c-muted);
  font-size: 15px;
  line-height: 1.85;
}

/* ---------- 14. CTA 区 ---------- */
.cta {
  position: relative;
  overflow: hidden;
  padding: 76px 0;
  background: linear-gradient(135deg, #0b1020 0%, #1c2f7a 100%);
  color: #fff;
  text-align: center;
}
.cta::before {
  content: "";
  position: absolute;
  inset: 0;
  background:
    radial-gradient(circle at 15% 20%, rgba(43, 92, 255, .5) 0%, transparent 45%),
    radial-gradient(circle at 85% 80%, rgba(0, 194, 168, .4) 0%, transparent 45%);
}
.cta__inner { position: relative; z-index: 1; }
.cta h2 {
  color: #fff;
  font-size: clamp(26px, 3.4vw, 36px);
  margin-bottom: 14px;
}
.cta p {
  max-width: 560px;
  margin: 0 auto 30px;
  color: rgba(255, 255, 255, .74);
  font-size: 16.5px;
}
.cta__actions { display: flex; justify-content: center; flex-wrap: wrap; gap: 14px; }

/* ---------- 15. 页脚 ---------- */
.site-footer {
  padding: 64px 0 28px;
  background: var(--c-dark);
  color: rgba(255, 255, 255, .62);
  font-size: 14.5px;
}
.site-footer__top {
  display: grid;
  grid-template-columns: 1.6fr repeat(3, 1fr);
  gap: 40px;
  padding-bottom: 40px;
  border-bottom: 1px solid rgba(255, 255, 255, .1);
}
.site-footer .brand { color: #fff; margin-bottom: 16px; }
.site-footer .brand__sub { color: rgba(255, 255, 255, .45); border-left-color: rgba(255, 255, 255, .18); }
.site-footer__intro { max-width: 340px; line-height: 1.8; }

.footer-col h4 {
  margin-bottom: 16px;
  font-size: 15px;
  color: #fff;
}
.footer-col li + li { margin-top: 10px; }
.footer-col a { transition: color .2s var(--ease); }
.footer-col a:hover { color: #fff; }

.site-footer__bottom {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  padding-top: 24px;
  font-size: 13.5px;
  color: rgba(255, 255, 255, .45);
}
.site-footer__bottom a:hover { color: #fff; }
.site-footer__links { display: flex; flex-wrap: wrap; gap: 18px; }

/* ---------- 16. 404 ---------- */
.notfound {
  min-height: calc(100vh - var(--header-h));
  display: grid;
  place-items: center;
  text-align: center;
  padding: 60px 0;
}
.notfound__code {
  font-size: clamp(80px, 16vw, 150px);
  font-weight: 800;
  line-height: 1;
  letter-spacing: -.04em;
  background: linear-gradient(120deg, var(--c-primary), var(--c-accent));
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}

/* ---------- 17. 滚动进场动效 ---------- */
[data-reveal] {
  opacity: 0;
  transform: translateY(22px);
  transition: opacity .65s var(--ease), transform .65s var(--ease);
}
[data-reveal].is-visible { opacity: 1; transform: none; }

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after {
    animation-duration: .01ms !important;
    transition-duration: .01ms !important;
  }
  [data-reveal] { opacity: 1; transform: none; }
}

/* ---------- 18. 响应式 ---------- */
@media (max-width: 1024px) {
  .hero__inner { grid-template-columns: 1fr; gap: 46px; }
  .hero__desc { max-width: none; }
  .split { gap: 40px; }
  .site-footer__top { grid-template-columns: 1fr 1fr; gap: 32px; }
  .grid--4 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}

@media (max-width: 860px) {
  .nav {
    position: fixed;
    top: var(--header-h);
    left: 0;
    right: 0;
    flex-direction: column;
    align-items: stretch;
    gap: 2px;
    padding: 14px 24px 22px;
    background: #fff;
    border-bottom: 1px solid var(--c-line);
    box-shadow: var(--shadow-m);
    transform: translateY(-12px);
    opacity: 0;
    visibility: hidden;
    transition: opacity .22s var(--ease), transform .22s var(--ease), visibility .22s;
  }
  .nav.is-open { opacity: 1; visibility: visible; transform: none; }
  .nav__link { padding: 12px 14px; font-size: 16px; }
  .nav-toggle { display: inline-flex; }
  .header-actions .btn { display: none; }

  .section { padding: 64px 0; }
  .grid--2, .grid--3, .grid--4 { grid-template-columns: 1fr; }
  .split { grid-template-columns: 1fr; }
  .split--reverse .split__media { order: 0; }
  .split + .split { margin-top: 56px; }
  .contact-grid { grid-template-columns: 1fr; }
  .stat-band__grid { grid-template-columns: repeat(2, 1fr); row-gap: 28px; }
  .hero { padding: 72px 0 68px; }
  .hero__stats { gap: 28px; }
  .brand__sub { display: none; }
}

@media (max-width: 520px) {
  .container { padding-inline: 18px; }
  .hero__actions .btn { width: 100%; }
  .site-footer__top { grid-template-columns: 1fr; }
  .card, .product-card__body, .panel { padding: 24px; }
}