/* ==========================================================================
   基础层：重置、缩放体系、容器、跨页面共用组件
   数值一律引用 css/tokens.css，规格说明见 docs/design-system.md
   ========================================================================== */

/* --------------------------------------------------------------------------
   1. 缩放体系
   1rem = 10px @1920。1280–1919 之间随视口等比缩放，保证版式与设计稿一致；
   1280 以下锁定根字号，改由断点重排，避免文字过小。
   -------------------------------------------------------------------------- */
html {
  font-size: 62.5%;
  -webkit-text-size-adjust: 100%;
}

@media (max-width: 1919px) {
  html {
    font-size: 0.52083vw;
  }
}

@media (max-width: 1279px) {
  html {
    font-size: 6.6px;
  }
}

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

body,
h1,
h2,
h3,
h4,
p,
dl,
dt,
dd,
figure,
ul,
ol {
  margin: 0;
}

ul,
ol {
  padding: 0;
  list-style: none;
}

body {
  font-family: var(--font-sans);
  font-size: var(--fs-body);
  line-height: var(--lh-body);
  color: var(--c-text);
  background: var(--c-page);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

img,
svg {
  display: block;
  max-width: 100%;
}

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

button {
  font: inherit;
  color: inherit;
  background: none;
  border: 0;
  cursor: pointer;
}

:focus-visible {
  outline: 0.2rem solid var(--c-primary);
  outline-offset: 0.2rem;
}

/* --------------------------------------------------------------------------
   3. 容器与区块
   -------------------------------------------------------------------------- */
.container {
  width: min(var(--container), 100% - var(--gutter) * 2);
  margin-inline: auto;
}

.skip-link {
  position: absolute;
  left: -9999px;
  top: 0;
  z-index: 100;
  padding: 1rem 2rem;
  background: var(--c-primary);
  color: var(--c-on-primary);
  font-size: var(--fs-footer-item);
}

.skip-link:focus {
  left: 1rem;
  top: 1rem;
}

/* 区块标题：居中，两侧「横线 + 圆点」装饰（横线 72×2，间隙 10，圆点 4×4，装饰距文字 28） */
.section-title {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 2.8rem;
  font-size: var(--fs-h2);
  line-height: var(--lh-tight);
  font-weight: 700;
  color: var(--c-title);
}

.section-title::before,
.section-title::after {
  content: "";
  flex: none;
  width: 8.6rem;
  height: 0.4rem;
}

.section-title::before {
  background:
    linear-gradient(var(--c-deco), var(--c-deco)) no-repeat left center / 7.2rem 0.2rem,
    radial-gradient(circle at center, var(--c-deco) 45%, transparent 50%) no-repeat right center / 0.4rem 0.4rem;
}

.section-title::after {
  background:
    radial-gradient(circle at center, var(--c-deco) 45%, transparent 50%) no-repeat left center / 0.4rem 0.4rem,
    linear-gradient(var(--c-deco), var(--c-deco)) no-repeat right center / 7.2rem 0.2rem;
}

/* --------------------------------------------------------------------------
   4. 共用组件：卡片、短横、小按钮
   -------------------------------------------------------------------------- */
.card {
  display: flex;
  flex-direction: column;
  overflow: hidden;
  background: var(--c-surface);
  border-radius: var(--r-card);
  box-shadow: var(--shadow-card);
  transition: box-shadow var(--dur) var(--ease), transform var(--dur) var(--ease);
}

.card:hover {
  box-shadow: var(--shadow-card-hover);
  transform: translateY(-0.4rem);
}

.card__body {
  display: flex;
  flex: 1;
  flex-direction: column;
  padding: var(--card-pad);
}

/* 描述下方的短横：紧跟描述（描述换行时短横跟着下移，与设计稿一致） */
.card-dash {
  display: block;
  width: 2.6rem;
  height: 0.2rem;
  margin-top: 1.3rem;
  background: var(--c-dash-soft);
}

/* 卡片按钮贴卡片右下角：同一行卡片描述行数不同时按钮仍然齐平（设计稿「抖音云连锁」即两行描述） */
.btn-mini {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  align-self: flex-end;
  margin-top: auto;
  width: 8.8rem;
  height: 2.4rem;
  border-radius: var(--r-pill);
  background: var(--c-primary);
  color: var(--c-on-primary);
  font-size: var(--fs-mini);
  line-height: 1;
  transition: background var(--dur) var(--ease);
}

.btn-mini:hover {
  background: var(--c-primary-strong);
}

/* --------------------------------------------------------------------------
   5. 顶部导航
   -------------------------------------------------------------------------- */
.site-header {
  position: relative;
  z-index: 20;
  background: var(--c-surface);
}

.site-header__inner {
  display: flex;
  align-items: center;
  height: var(--header-h);
  padding-left: var(--header-pad-left);
  padding-right: var(--header-pad-right);
}

.site-header__logo img {
  width: auto;
  height: 4.5rem;
}

.site-nav {
  align-self: stretch;
  margin-left: auto;
  margin-right: 4rem;
}

.site-nav__list {
  display: flex;
  align-items: stretch;
  height: 100%;
  gap: 6rem;
}

.site-nav__link {
  position: relative;
  display: flex;
  align-items: center;
  height: 100%;
  font-size: var(--fs-nav);
  line-height: 1.5;
  color: var(--c-title);
  white-space: nowrap;
  transition: color var(--dur) var(--ease);
}

.site-nav__link:hover {
  color: var(--c-primary);
}

/* 当前栏目：通高蓝块（page_2 实测块宽 146、通高 116，白字）
   蓝块用伪元素向两侧撑开并垫在文字后面：不参与布局，其余导航项位置不变 */
.site-nav__link[aria-current="page"] {
  color: var(--c-on-primary);
}

.site-nav__link[aria-current="page"]::before {
  content: "";
  position: absolute;
  inset: 0 -3.6rem;
  z-index: -1;
  background: var(--c-primary);
}

.site-header__cta {
  display: grid;
  place-items: center;
  align-self: stretch;
  width: 14rem;
  flex: none;
  background: var(--c-primary);
  color: var(--c-on-primary);
  font-size: var(--fs-nav);
  transition: background var(--dur) var(--ease);
}

.site-header__cta:hover {
  background: var(--c-primary-strong);
}

.nav-toggle {
  display: none;
  margin-left: auto;
  width: 4.8rem;
  height: 4.8rem;
  flex: none;
  place-items: center;
}

.nav-toggle__bar {
  position: relative;
  display: block;
  width: 2.6rem;
  height: 0.2rem;
  background: var(--c-title);
}

.nav-toggle__bar::before,
.nav-toggle__bar::after {
  content: "";
  position: absolute;
  left: 0;
  width: 100%;
  height: 100%;
  background: inherit;
}

.nav-toggle__bar::before {
  top: -0.8rem;
}

.nav-toggle__bar::after {
  top: 0.8rem;
}

/* --------------------------------------------------------------------------
   6. 子页骨架：面包屑 + 左侧栏目导航 + 主列
   实测（page_2）：面包屑条通栏高 94、底部 1px 线；栏目导航贴页面左缘、宽 336；
   主列 360–1680（宽 1320），右侧留白 240。
   -------------------------------------------------------------------------- */
.crumb {
  border-bottom: 0.2rem solid var(--c-line-soft);
  background: var(--c-surface);
}

.crumb__inner {
  display: flex;
  align-items: center;
  justify-content: flex-end;
  gap: 0.8rem;
  height: 9.4rem;
  padding-right: 9.2rem;
  font-size: var(--fs-crumb);
  line-height: 1.5;
  color: var(--c-text);
}

.crumb__home {
  width: 2.4rem;
  height: 2.4rem;
  flex: none;
  color: var(--c-subtle);
}

.crumb a {
  transition: color var(--dur) var(--ease);
}

.crumb a:hover {
  color: var(--c-primary);
}

.crumb__sep {
  color: var(--c-subtle);
}

.crumb [aria-current="page"] {
  color: var(--c-primary);
}

/* 左栏 + 主列：左栏贴页面左缘，因此这里不用 .container 而用显式列宽 */
.subpage {
  display: grid;
  grid-template-columns: var(--side-w) minmax(0, 1fr);
  gap: var(--side-gap);
  padding-right: var(--page-pad-right);
}

.side-nav {
  padding-top: 4.2rem;
}

.side-nav__link {
  position: relative;
  display: flex;
  align-items: center;
  height: 6rem;
  padding-left: 12rem;
  font-size: var(--fs-side);
  color: var(--c-text);
  transition: color var(--dur) var(--ease), background var(--dur) var(--ease);
}

/* 文字左缘 120、竖细线 96：细线贯通整列 */
.side-nav__link::before {
  content: "";
  position: absolute;
  left: 9.6rem;
  top: 0;
  bottom: 0;
  width: 1px;
  background: var(--c-line);
}

/* 两字、三字栏目名在设计稿里被拉开到与四字同宽（104） */
.side-nav__label {
  width: 10.6rem;
  text-align: justify;
  text-align-last: justify;
}

.side-nav__link:hover {
  color: var(--c-primary);
}

.side-nav__link[aria-current="page"] {
  background: var(--c-primary);
  color: var(--c-on-primary);
}

/* 当前项：竖细线换成白色短标 */
.side-nav__link[aria-current="page"]::before {
  top: 50%;
  bottom: auto;
  width: 0.6rem;
  height: 2.4rem;
  background: var(--c-on-primary);
  transform: translateY(-50%);
}

/* 子页区块标题：居中 + 通栏细线，线上叠一段居中蓝标（56×4） */
.page-title {
  font-size: var(--fs-h2-sm);
  line-height: var(--lh-tight);
  font-weight: 700;
  color: var(--c-title);
  text-align: center;
}

.page-title::after {
  content: "";
  display: block;
  height: 0.4rem;
  margin-top: 3.6rem;
  background:
    linear-gradient(var(--c-primary), var(--c-primary)) no-repeat center / 5.6rem 0.4rem,
    linear-gradient(var(--c-line), var(--c-line)) no-repeat center / 100% 0.2rem;
}

/* 子页正文：首行缩进 2 字，段间沿用同一行距（设计稿两段之间无额外间距） */
.prose > p {
  font-size: var(--fs-body);
  line-height: var(--lh-prose);
  color: var(--c-text);
  text-indent: 2em;
}

/* --------------------------------------------------------------------------
   7. 页脚
   四栏栏宽实测不等：268 / 332 / 326 / 剩余
   -------------------------------------------------------------------------- */
.site-footer {
  border-top: 1px solid var(--c-line);
  background: var(--c-footer-bg);
}

.site-footer__cols {
  display: grid;
  grid-template-columns: 26.8rem 33.2rem 32.6rem auto;
  padding-top: 4.8rem;
  padding-bottom: 4.2rem;
}

.footer-col__title {
  font-size: var(--fs-footer-title);
  line-height: var(--lh-tight);
  font-weight: 400;
  color: var(--c-title);
}

.footer-col__dash {
  display: block;
  width: 3.6rem;
  height: 0.2rem;
  margin-top: 3.6rem;
  background: var(--c-dash);
}

.footer-col__list {
  margin-top: 5.2rem;
}

.footer-col__list > li {
  font-size: var(--fs-footer-item);
  line-height: 3rem;
  color: var(--c-muted);
}

.footer-col__list > li + li {
  margin-top: 2rem;
}

.footer-col__list a {
  transition: color var(--dur) var(--ease);
}

.footer-col__list a:hover {
  color: var(--c-primary);
}

.site-footer__bottom {
  border-top: 1px solid var(--c-line);
  padding: 3rem 0 2.8rem;
  font-size: var(--fs-footer-item);
  line-height: 3rem;
  color: var(--c-subtle);
  text-align: center;
}

/* --------------------------------------------------------------------------
   8. 断点：≤1279 子页收紧留白；≤1023 导航收进抽屉、栏目导航转为横向
   -------------------------------------------------------------------------- */
/* 1024–1439：9 个导航项按设计稿间距会把 logo 挤出画面，这里收紧留白与项间距 */
@media (max-width: 1439px) {
  .site-header__inner {
    padding-left: 4.8rem;
    padding-right: 4.8rem;
  }

  .site-nav {
    margin-right: 2.4rem;
  }

  .site-nav__list {
    gap: 3.2rem;
  }

  .site-nav__link[aria-current="page"]::before {
    inset: 0 -1.6rem;
  }
}

@media (max-width: 1279px) {
  .subpage {
    --page-pad-right: var(--gutter);
    --side-w: 26rem;
  }

  .side-nav__link {
    padding-left: 6.4rem;
  }

  .side-nav__link::before {
    left: 4rem;
  }

  .crumb__inner {
    padding-right: var(--gutter);
  }
}

@media (max-width: 1023px) {
  .site-header__inner {
    padding-inline: var(--gutter);
  }

  .nav-toggle {
    display: grid;
  }

  .site-nav {
    position: absolute;
    left: 0;
    right: 0;
    top: 100%;
    margin: 0;
    max-height: 0;
    overflow: hidden;
    background: var(--c-surface);
    box-shadow: var(--shadow-card);
    transition: max-height var(--dur) var(--ease);
  }

  .site-nav.is-open {
    max-height: 80vh;
    overflow-y: auto;
  }

  .site-nav__list {
    display: block;
    height: auto;
    padding: 1rem var(--gutter) 2rem;
  }

  .site-nav__list > li + li {
    border-top: 1px solid var(--c-line-soft);
  }

  .site-nav__link {
    display: block;
    height: auto;
    padding: 1.6rem 0;
  }

  /* 抽屉里的当前项还原成普通行，只留蓝字 */
  .site-nav__link[aria-current="page"] {
    color: var(--c-primary);
  }

  .site-nav__link[aria-current="page"]::before {
    content: none;
  }

  /* 栏目导航改为横向排布，跟在面包屑之后 */
  .subpage {
    display: block;
    padding-right: 0;
    padding-inline: var(--gutter);
  }

  .side-nav {
    padding-top: 2.4rem;
  }

  .side-nav__list {
    display: flex;
    flex-wrap: wrap;
    gap: 1.2rem;
  }

  .side-nav__link {
    height: 5.2rem;
    padding-inline: 2.4rem;
    border: 1px solid var(--c-line-soft);
    border-radius: var(--r-pill);
    font-size: var(--fs-body);
  }

  .side-nav__link::before {
    content: none;
  }

  .side-nav__label {
    width: auto;
    text-align-last: auto;
  }

  .page-title::after {
    margin-top: 2.4rem;
  }

  .site-header__cta {
    width: auto;
    padding-inline: 2.4rem;
    margin-left: 1.6rem;
  }

  .site-footer__cols {
    grid-template-columns: repeat(2, 1fr);
    gap: 4.8rem var(--grid-gap);
  }
}

@media (max-width: 767px) {
  .section-title::before,
  .section-title::after {
    width: 4rem;
    background-size: 2.6rem 0.2rem, 0.4rem 0.4rem;
  }

  .section-title {
    gap: 1.6rem;
  }

  .site-footer__cols {
    grid-template-columns: 1fr;
    gap: 4rem;
  }
}