/* ==========================================================================
   SINNBO 成都青迅科技 — 设计系统
   令牌 → 基础 → 布局 → 组件(头部/页脚/卡片/标签/表单类) → 页面区块 → 动效
   ========================================================================== */

/* ---------- 令牌 ---------- */
:root {
  /* 色彩:取自 logo 采样(蓝 #0095d4 / 绿 #85c32a),交互蓝加深以满足对比度 */
  --ink: #12202e;
  --body-c: #394a5a;
  --muted: #5c6f80;
  --blue-500: #0095d4;
  --blue-600: #0a76ad;
  --blue-700: #085a86;
  --blue-050: #eef7fc;
  --green-500: #85c32a;
  --green-050: #f3f9e8;
  --green-700: #4e7514;
  --navy-900: #0b1f30;
  --navy-800: #10283c;
  --line: #e3e9ee;
  --surface: #f6f9fb;
  --white: #fff;

  --shadow-sm: 0 1px 2px rgba(11, 31, 48, .06);
  --shadow-md: 0 12px 32px rgba(11, 31, 48, .10);

  --radius: 12px;
  --radius-sm: 8px;

  --header-h: 72px;
  --container: 1140px;
  --z-nav: 100;
  --z-dropdown: 90;
  --z-mobile: 200;

  --font: "Segoe UI", "PingFang SC", "Microsoft YaHei", "Noto Sans SC", "Source Han Sans SC", sans-serif;
}

/* ---------- 基础 ---------- */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

html { scroll-behavior: smooth; scroll-padding-top: calc(var(--header-h) + 20px); }

body {
  font-family: var(--font);
  font-size: 16px;
  line-height: 1.75;
  color: var(--body-c);
  background: var(--white);
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

h1, h2, h3, h4 { color: var(--ink); line-height: 1.3; font-weight: 700; text-wrap: balance; }
p { text-wrap: pretty; }
a { color: var(--blue-600); text-decoration: none; }
img { max-width: 100%; display: block; }
ul, ol { list-style: none; }
button { font-family: inherit; }
strong { color: var(--ink); }
::placeholder { color: var(--muted); }

:focus-visible { outline: 2px solid var(--blue-600); outline-offset: 2px; border-radius: 4px; }

[hidden] { display: none !important; }

.icon { width: 1.25em; height: 1.25em; flex: none; fill: none; stroke: currentColor; stroke-width: 2; stroke-linecap: round; stroke-linejoin: round; }
.icon--sm { width: 1em; height: 1em; }

.sr-only {
  position: absolute; width: 1px; height: 1px; margin: -1px;
  clip: rect(0 0 0 0); overflow: hidden; white-space: nowrap;
}

.skip-link {
  position: fixed; top: -48px; left: 16px; z-index: var(--z-mobile);
  background: var(--blue-600); color: #fff; padding: 10px 18px; border-radius: var(--radius-sm);
  font-size: 14px; transition: top .16s ease-out;
}
.skip-link:focus { top: 12px; color: #fff; }

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

.section { padding-block: clamp(56px, 8vw, 96px); }
.section--tint { background: var(--surface); }
.section--tight { padding-block: clamp(40px, 6vw, 64px); }

.section-head {
  display: flex; align-items: flex-end; justify-content: space-between;
  gap: 24px; margin-bottom: clamp(32px, 5vw, 48px);
}
.section-head h2 { font-size: clamp(24px, 3vw, 30px); letter-spacing: .01em; }
.section-head .sub { color: var(--muted); margin-top: 10px; max-width: 56ch; font-size: 15.5px; }
.section-head .head-link { flex: none; font-size: 14.5px; font-weight: 600; display: inline-flex; align-items: center; gap: 6px; }
.section-head .head-link .icon { transition: transform .16s ease-out; }
.section-head .head-link:hover .icon { transform: translateX(3px); }

.block-title { font-size: clamp(19px, 2.2vw, 23px); }
.block-title::after {
  content: ""; display: block; width: 36px; height: 3px;
  background: var(--green-500); border-radius: 2px; margin-top: 12px;
}

/* ---------- 按钮 ---------- */
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 8px;
  font-weight: 600; font-size: 15px; line-height: 1.4;
  padding: 13px 26px; border-radius: var(--radius-sm); border: 1px solid transparent;
  cursor: pointer; transition: background-color .18s ease-out, border-color .18s ease-out, color .18s ease-out;
}
.btn .icon { width: 1.1em; height: 1.1em; }
.btn--primary { background: var(--blue-600); color: #fff; }
.btn--primary:hover { background: var(--blue-700); color: #fff; }
.btn--ghost { border-color: rgba(255, 255, 255, .45); color: #fff; }
.btn--ghost:hover { border-color: #fff; background: rgba(255, 255, 255, .08); color: #fff; }
.btn--outline { border-color: var(--line); color: var(--blue-600); background: var(--white); }
.btn--outline:hover { border-color: var(--blue-600); background: var(--blue-050); }

/* ---------- 头部 ---------- */
.site-header {
  position: sticky; top: 0; z-index: var(--z-nav);
  background: rgba(255, 255, 255, .96); backdrop-filter: blur(8px);
  border-bottom: 1px solid var(--line);
}
.site-header.is-scrolled { box-shadow: 0 6px 20px rgba(11, 31, 48, .07); }
.site-header__in { height: var(--header-h); display: flex; align-items: center; gap: 28px; }

.brand { flex: none; display: flex; align-items: center; }
.brand img { height: 32px; width: auto; }

.site-nav { margin-left: auto; display: flex; align-items: center; gap: 2px; }
.nav-link {
  position: relative; display: inline-flex; align-items: center; gap: 6px;
  height: var(--header-h); padding-inline: 15px;
  font-size: 15px; font-weight: 500; color: #26384a;
  background: none; border: 0; cursor: pointer;
  transition: color .16s ease-out;
}
.nav-link:hover { color: var(--blue-600); }
.nav-link[aria-current="page"] { color: var(--blue-600); font-weight: 600; }
.nav-link[aria-current="page"]::after {
  content: ""; position: absolute; left: 15px; right: 15px; bottom: 0;
  height: 2px; border-radius: 2px 2px 0 0; background: var(--blue-500);
}
.nav-link .icon { transition: transform .16s ease-out; color: var(--muted); }

/* 下拉 */
.nav-drop { display: flex; }
.nav-drop__menu {
  position: absolute; top: calc(100% - 10px); left: 50%; transform: translate(-50%, 6px);
  min-width: 200px; padding: 6px;
  background: var(--white); border: 1px solid var(--line); border-radius: 10px;
  box-shadow: var(--shadow-md);
  opacity: 0; visibility: hidden;
  transition: opacity .16s ease-out, transform .16s ease-out, visibility .16s;
  z-index: var(--z-dropdown);
}
.nav-drop:hover .nav-drop__menu,
.nav-drop:focus-within .nav-drop__menu,
.nav-drop.is-open .nav-drop__menu { opacity: 1; visibility: visible; transform: translate(-50%, 0); }
.nav-drop:hover> .nav-link .icon,
.nav-drop.is-open > .nav-link .icon { transform: rotate(180deg); color: var(--blue-600); }
.nav-drop__menu a {
  display: block; padding: 10px 14px; border-radius: 8px;
  font-size: 14px; color: #2c3e50; transition: background-color .14s, color .14s;
}
.nav-drop__menu a:hover { background: var(--blue-050); color: var(--blue-700); }
.nav-drop__menu a[aria-current="page"] { background: var(--blue-050); color: var(--blue-600); font-weight: 600; }

.header-phone {
  flex: none; display: inline-flex; align-items: center; gap: 9px;
  padding: 9px 18px; border: 1px solid var(--line); border-radius: 999px;
  font-size: 15px; font-weight: 600; color: var(--blue-600);
  transition: border-color .16s, background-color .16s;
}
.header-phone:hover { border-color: var(--blue-600); background: var(--blue-050); }

.nav-toggle {
  display: none; align-items: center; justify-content: center;
  width: 42px; height: 42px; margin-left: auto;
  background: none; border: 1px solid var(--line); border-radius: var(--radius-sm);
  color: var(--ink); cursor: pointer; font-size: 19px;
}

/* 移动端导航 */
.mobile-nav {
  display: none; position: fixed; inset: var(--header-h) 0 0 0;
  background: var(--white); z-index: var(--z-mobile);
  padding: 12px 24px 32px; overflow: auto;
}
.mobile-nav.is-open { display: block; }
.mobile-nav a {
  display: flex; align-items: center; justify-content: space-between;
  padding: 15px 4px; font-size: 16.5px; font-weight: 500; color: var(--ink);
  border-bottom: 1px solid var(--line);
}
.mobile-nav a:hover { color: var(--blue-600); }
.mobile-nav a[aria-current="page"] { color: var(--blue-600); }
.mobile-nav .mobile-group { margin-top: 20px; font-size: 13px; color: var(--muted); letter-spacing: .04em; }
.mobile-nav a.btn { display: inline-flex; justify-content: center; border-bottom: 0; color: #fff; font-size: 15px; font-weight: 600; }
.mobile-nav .btn { margin-top: 24px; width: 100%; }

@media (max-width: 920px) {
  .site-nav, .header-phone { display: none; }
  .nav-toggle { display: inline-flex; }
  body.nav-locked { overflow: hidden; }
}
@media (min-width: 921px) { .mobile-nav { display: none !important; } }

/* ---------- 首页 Hero ---------- */
.hero { position: relative; background: var(--navy-900); color: #fff; overflow: hidden; }
.hero__bg {
  position: absolute; inset: 0;
  background: url("../img/hero-net.jpg") right center / cover no-repeat;
  opacity: .45;
}
.hero__bg::after {
  content: ""; position: absolute; inset: 0;
  background: linear-gradient(90deg, var(--navy-900) 34%, rgba(11, 31, 48, .42) 100%);
}
.hero__in { position: relative; padding-block: clamp(76px, 11vw, 136px); }
.hero h1 {
  color: #fff; font-size: clamp(30px, 4.6vw, 50px);
  letter-spacing: .015em; line-height: 1.28; max-width: 21em;
}
.hero .lede {
  color: #c3d3e0; font-size: clamp(15px, 1.6vw, 17.5px);
  margin-top: 22px; max-width: 54ch;
}
.hero__cta { margin-top: 38px; display: flex; gap: 14px; flex-wrap: wrap; }
.hero__badges {
  margin-top: clamp(44px, 6vw, 64px); padding-top: 26px;
  border-top: 1px solid rgba(255, 255, 255, .14);
  display: flex; gap: 14px 40px; flex-wrap: wrap;
}
.badge-item { display: inline-flex; align-items: center; gap: 10px; color: #d7e3ee; font-size: 14px; }
.badge-item .icon { color: var(--green-500); }

/* ---------- 内页 Hero ---------- */
.page-hero { position: relative; background: var(--navy-900); color: #fff; overflow: hidden; }
.page-hero__bg { position: absolute; inset: 0; background-size: cover; background-position: center; opacity: .12; }
.page-hero::after {
  content: ""; position: absolute; inset: 0;
  background: linear-gradient(180deg, rgba(11, 31, 48, .2), rgba(11, 31, 48, .65));
  pointer-events: none;
}
.page-hero__in { position: relative; padding-block: clamp(52px, 7vw, 88px); }
.page-hero h1 { color: #fff; font-size: clamp(27px, 3.6vw, 40px); margin-top: 16px; letter-spacing: .015em; }
.page-hero .lede { color: #c3d3e0; margin-top: 14px; max-width: 62ch; font-size: 16px; }
.crumbs { display: flex; align-items: center; gap: 8px; font-size: 13.5px; color: #b6c7d6; flex-wrap: wrap; }
.crumbs a { color: #d7e3ee; }
.crumbs a:hover { color: #fff; }
.crumbs .icon { width: .9em; height: .9em; opacity: .7; }

/* ---------- 卡片 ---------- */
.card {
  display: flex; flex-direction: column; overflow: hidden;
  background: var(--white); border: 1px solid var(--line); border-radius: var(--radius);
  transition: transform .2s ease-out, box-shadow .2s ease-out;
}
a.card { color: inherit; }
a.card:hover { transform: translateY(-3px); box-shadow: var(--shadow-md); }
.card__img { width: 100%; aspect-ratio: 16 / 9; object-fit: cover; }
.card__body { display: flex; flex-direction: column; gap: 10px; flex: 1; padding: 24px; }
.card__body h3 { font-size: 19px; }
.card__body p { font-size: 14.5px; color: var(--muted); }
.card__link {
  margin-top: auto; padding-top: 8px;
  display: inline-flex; align-items: center; gap: 6px;
  font-size: 14px; font-weight: 600; color: var(--blue-600);
}
a.card:hover .card__link .icon { transform: translateX(3px); }
.card__link .icon { transition: transform .16s ease-out; }

.grid-3 { display: grid; grid-template-columns: repeat(auto-fit, minmax(280px, 1fr)); gap: 24px; }
.grid-2 { display: grid; grid-template-columns: repeat(auto-fit, minmax(320px, 1fr)); gap: 24px; }

/* 面板(内容块容器) */
.panel { background: var(--white); border: 1px solid var(--line); border-radius: var(--radius); padding: clamp(24px, 4vw, 40px); }

/* ---------- 客户 logo 墙 ---------- */
.logo-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(238px, 1fr)); gap: 16px; }
.logo-tile {
  display: flex; flex-direction: column; align-items: center; justify-content: center; gap: 12px;
  padding: 22px 14px 16px; min-height: 128px;
  background: var(--white); border: 1px solid var(--line); border-radius: 10px;
  transition: border-color .16s ease-out;
}
.logo-tile img { height: 66px; width: auto; max-width: 100%; object-fit: contain; opacity: .92; transition: opacity .2s ease-out; }
.logo-tile .tile-name { font-size: 13px; font-weight: 500; color: var(--muted); letter-spacing: .02em; }
.logo-tile:hover { border-color: #c9d8e3; }
.logo-tile:hover img { opacity: 1; }
.logo-tile--more span { font-size: 14px; font-weight: 600; color: var(--muted); }
@media (max-width: 600px) { .logo-grid { grid-template-columns: repeat(2, 1fr); } .logo-tile--wide { grid-column: span 2; } }

/* ---------- 新闻列表 ---------- */
.news-list { background: var(--white); border: 1px solid var(--line); border-radius: var(--radius); padding: 8px clamp(20px, 3vw, 36px); }
.news-row {
  display: flex; align-items: baseline; gap: 24px;
  padding: 19px 2px; border-bottom: 1px solid var(--line);
}
.news-row:last-child { border-bottom: 0; }
.news-row time { flex: none; width: 104px; font-size: 13.5px; color: var(--muted); font-variant-numeric: tabular-nums; }
.news-row h3 { font-size: 16px; font-weight: 600; line-height: 1.55; }
.news-row a { color: var(--ink); transition: color .14s; }
.news-row a:hover { color: var(--blue-600); }

/* ---------- 关于 / 选项卡 ---------- */
.about-grid { display: grid; grid-template-columns: 1fr 1.1fr; gap: clamp(28px, 5vw, 56px); align-items: start; }
.about-grid__img { border-radius: var(--radius); overflow: hidden; border: 1px solid var(--line); }
.about-grid__img img { width: 100%; height: 100%; object-fit: cover; }

.tabs { display: flex; gap: 6px; border-bottom: 1px solid var(--line); }
.tab {
  position: relative; padding: 11px 18px;
  background: none; border: 0; cursor: pointer;
  font-size: 15px; font-weight: 600; color: var(--muted);
  transition: color .16s ease-out;
}
.tab:hover { color: var(--ink); }
.tab[aria-selected="true"] { color: var(--blue-600); }
.tab[aria-selected="true"]::after {
  content: ""; position: absolute; left: 0; right: 0; bottom: -1px; height: 2px;
  background: var(--blue-500); border-radius: 2px;
}
.tabpanel { padding-top: 22px; }
.tabpanel p + p { margin-top: 14px; }
.tabpanel .prose { max-width: 62ch; }

.contact-list { display: flex; flex-direction: column; gap: 16px; }
.contact-list li { display: flex; gap: 14px; align-items: center; font-size: 15px; }
.contact-list .icon-wrap {
  flex: none; width: 38px; height: 38px; border-radius: 10px;
  background: var(--blue-050); color: var(--blue-600);
  display: inline-flex; align-items: center; justify-content: center;
}
.contact-list .icon-wrap .icon { width: 17px; height: 17px; }
.contact-list a { color: var(--body-c); }
.contact-list a:hover { color: var(--blue-600); }

/* ---------- 标签 ---------- */
.chip {
  display: inline-flex; align-items: center; padding: 5px 14px; border-radius: 999px;
  font-size: 13.5px; font-weight: 500; line-height: 1.6;
  background: var(--blue-050); color: var(--blue-700);
}
.chip--green { background: var(--green-050); color: var(--green-700); }
.chip--slate { background: #eef2f6; color: #42566a; }
.chip-cloud { display: flex; flex-wrap: wrap; gap: 10px; }

/* ---------- 功能组(教育三端) ---------- */
.role-group { display: grid; grid-template-columns: 220px 1fr; gap: 24px; padding-block: 28px; border-bottom: 1px solid var(--line); }
.role-group:last-child { border-bottom: 0; }
.role-group__head { display: flex; flex-direction: column; gap: 6px; }
.role-group__head .role-name { display: inline-flex; align-items: center; gap: 10px; font-size: 17px; font-weight: 700; color: var(--ink); }
.role-group__head .role-name .icon { color: var(--blue-600); }
.role-group__head .role-count { font-size: 13px; color: var(--muted); }
@media (max-width: 720px) { .role-group { grid-template-columns: 1fr; gap: 16px; } }

/* ---------- 清单(绿色对勾) ---------- */
.check-list { display: flex; flex-direction: column; gap: 12px; }
.check-list li { display: flex; gap: 11px; align-items: flex-start; font-size: 15px; }
.check-list .icon { color: var(--green-500); margin-top: 4px; width: 1.1em; height: 1.1em; }

/* ---------- 切换器(砂石产品) ---------- */
.switcher { display: grid; grid-template-columns: 300px minmax(0, 1fr); gap: 28px; align-items: start; }
.switcher__menu {
  display: flex; flex-direction: column; gap: 4px; padding: 10px;
  background: var(--white); border: 1px solid var(--line); border-radius: var(--radius);
  position: sticky; top: calc(var(--header-h) + 16px);
}
.switcher__btn {
  display: flex; align-items: center; justify-content: space-between; gap: 10px;
  padding: 12px 15px; border: 0; border-radius: var(--radius-sm);
  background: none; text-align: left; cursor: pointer;
  font-size: 14.5px; font-weight: 500; color: #33475b;
  transition: background-color .16s ease-out, color .16s ease-out;
}
.switcher__btn:hover { background: var(--blue-050); }
.switcher__btn.is-active { background: var(--blue-050); color: var(--blue-700); font-weight: 600; }
.switcher__btn .icon { opacity: 0; transform: translateX(-4px); transition: opacity .16s, transform .16s; color: var(--blue-600); }
.switcher__btn.is-active .icon { opacity: 1; transform: none; }
@media (max-width: 860px) {
  .switcher { grid-template-columns: 1fr; }
  .switcher__menu { position: static; flex-direction: row; flex-wrap: wrap; }
  .switcher__btn { padding: 9px 13px; font-size: 13.5px; border: 1px solid var(--line); }
  .switcher__btn .icon { display: none; }
}

/* ---------- 案例 ---------- */
.case-feature { display: grid; grid-template-columns: 1.05fr .95fr; gap: clamp(28px, 5vw, 56px); align-items: center; }
.case-feature__imgs { display: grid; grid-template-columns: 1fr 1fr; gap: 12px; }
.case-feature__imgs img { width: 100%; aspect-ratio: 4 / 3; object-fit: cover; border-radius: 10px; border: 1px solid var(--line); }
.case-feature__imgs img:first-child { grid-column: 1 / -1; aspect-ratio: 16 / 9; }
.case-tag { display: inline-flex; align-items: center; gap: 8px; font-size: 13.5px; font-weight: 600; color: var(--blue-600); margin-bottom: 14px; }
.case-stats { display: flex; gap: clamp(24px, 4vw, 48px); margin-top: 30px; padding-top: 24px; border-top: 1px solid var(--line); flex-wrap: wrap; }
.case-stats .num { font-size: 30px; font-weight: 700; color: var(--blue-600); line-height: 1.2; font-variant-numeric: tabular-nums; }
.case-stats .num small { font-size: 16px; font-weight: 600; }
.case-stats .label { font-size: 13.5px; color: var(--muted); margin-top: 4px; }
@media (max-width: 860px) { .case-feature { grid-template-columns: 1fr; } }

.mini-case {
  display: flex; flex-direction: column; gap: 14px;
  background: var(--white); border: 1px solid var(--line); border-radius: var(--radius); padding: 26px;
}
.mini-case__logo { height: 44px; display: flex; align-items: center; }
.mini-case__logo img { max-height: 100%; max-width: 128px; object-fit: contain; }
.mini-case h3 { font-size: 17px; }
.mini-case p { font-size: 14px; color: var(--muted); }

/* ---------- CTA 横幅 ---------- */
.cta-band { background: var(--navy-900); color: #fff; overflow: hidden; position: relative; }
.cta-band__in {
  position: relative; display: flex; align-items: center; justify-content: space-between;
  gap: 24px; padding-block: clamp(44px, 6vw, 64px); flex-wrap: wrap;
}
.cta-band h2 { color: #fff; font-size: clamp(21px, 2.6vw, 27px); }
.cta-band p { color: #b7c8d6; margin-top: 8px; font-size: 15px; }
.cta-band__actions { display: flex; gap: 14px; flex-wrap: wrap; }

/* ---------- 页脚 ---------- */
.site-footer { background: var(--navy-900); color: #a8bccb; }
.site-footer__top {
  display: grid; grid-template-columns: 1.5fr 1fr 1fr 1.4fr; gap: 40px;
  padding-block: clamp(48px, 7vw, 64px) 44px;
}
.footer-logo { height: 26px; width: auto; }
.footer-desc { margin-top: 18px; font-size: 14px; line-height: 1.85; max-width: 34ch; }
.site-footer h4 { color: #fff; font-size: 14.5px; font-weight: 600; letter-spacing: .04em; margin-bottom: 18px; }
.footer-links { display: flex; flex-direction: column; gap: 11px; font-size: 14px; }
.footer-links a, .footer-contact a { color: #a8bccb; transition: color .14s; }
.footer-links a:hover, .footer-contact a:hover { color: #fff; }
.footer-contact { display: flex; flex-direction: column; gap: 13px; font-size: 14px; }
.footer-contact li { display: flex; gap: 10px; align-items: flex-start; }
.footer-contact .icon { width: 15px; height: 15px; margin-top: 4px; color: #6f8ba0; }
.site-footer__bottom {
  display: flex; align-items: center; justify-content: space-between; gap: 8px 24px; flex-wrap: wrap;
  border-top: 1px solid rgba(255, 255, 255, .12); padding-block: 20px;
  font-size: 13px; color: #7e93a5;
}
.site-footer__bottom a { color: #7e93a5; }
.site-footer__bottom a:hover { color: #fff; }
@media (max-width: 860px) { .site-footer__top { grid-template-columns: 1fr 1fr; } }
@media (max-width: 520px) { .site-footer__top { grid-template-columns: 1fr; gap: 32px; } }

/* ---------- 动效:仅保留 hover/滚动等过渡;不做滚动入场(可靠性优先) ---------- */

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { transition-duration: .01ms !important; animation-duration: .01ms !important; }
}