/* ==========================================================================
   创与惟 官网样式
   方向：冷调矿石灰底 + 单一品牌青色，无衬线排版，真实素材优先
   ========================================================================== */

/* ---------- 字体（全部自托管，国内可访问） ---------- */
@font-face {
  font-family: "Geist";
  src: url("../fonts/Geist-latin.woff2") format("woff2");
  font-weight: 400 700;
  font-display: swap;
  unicode-range: U+0000-00FF, U+0131, U+0152-0153, U+02BB-02BC, U+02C6, U+02DA, U+02DC, U+2000-206F, U+20AC, U+2122, U+2191, U+2193, U+2212, U+2215;
}
@font-face {
  font-family: "Geist Mono";
  src: url("../fonts/GeistMono-latin.woff2") format("woff2");
  font-weight: 400 500;
  font-display: swap;
}
/* 按页面实际用字裁剪的思源黑体，重新生成见 tools/subset-fonts.py */
@font-face {
  font-family: "CYW Sans SC";
  src: url("../fonts/NotoSansSC-subset.woff2") format("woff2");
  font-weight: 300 900;
  font-display: swap;
}

/* ---------- 设计变量 ---------- */
:root {
  /* 颜色 */
  --paper: #EEF1F0;          /* 矿石灰：页面底色 */
  --paper-deep: #E3E8E6;     /* 深一档：分区底色 */
  --surface: #F8FAF9;        /* 卡片面 */
  --ink: #0E1B1D;            /* 墨：标题与正文 */
  --ink-soft: #3E4D51;       /* 次级正文 */
  --mute: #56656A;           /* 注释、来源 */
  --line: rgba(14, 27, 29, 0.12);
  --line-strong: rgba(14, 27, 29, 0.22);
  --accent: #0E6B70;         /* 品牌青，取自原 logo 色系并降低饱和 */
  --accent-deep: #0A5256;
  --accent-soft: #D5E6E4;
  --night: #0C1D20;          /* 收尾深色区 */
  --night-2: #13292D;
  --on-night: #E7EEED;
  --on-night-mute: #9FB2B0;
  --accent-on-night: #8FCFC7;
  --danger-on-night: #F2A596;
  --danger: #A23B2C;

  /* 字体 */
  --font-sans: "Geist", "CYW Sans SC", "PingFang SC", "HarmonyOS Sans SC", "Hiragino Sans GB", "Microsoft YaHei", "Noto Sans SC", sans-serif;
  --font-mono: "Geist Mono", ui-monospace, "SFMono-Regular", Menlo, Consolas, monospace;

  --text-sm: 0.875rem;
  --text-base: 1rem;
  --text-md: 1.125rem;
  --text-lg: clamp(1.25rem, 1.1rem + 0.5vw, 1.5rem);
  --text-xl: clamp(1.5rem, 1.2rem + 1vw, 2rem);
  --text-section: clamp(2rem, 1.4rem + 2.2vw, 3.25rem);
  --text-hero: clamp(2.5rem, 1.1rem + 4.4vw, 5.25rem);

  /* 间距与尺寸 */
  --gutter: clamp(1rem, 0.5rem + 2vw, 2.5rem);
  --container: 1320px;
  --section-y: clamp(5rem, 3.5rem + 5vw, 9rem);
  --header-h: 72px;

  /* 圆角规则：容器 20px，媒体 14px，输入框 10px，按钮全圆 */
  --r-card: 20px;
  --r-media: 14px;
  --r-input: 10px;

  /* 阴影：带青色调，不用纯黑 */
  --shadow-lift: 0 1px 2px rgba(14, 60, 64, 0.06), 0 12px 32px -12px rgba(14, 60, 64, 0.22);

  /* 动效 */
  --ease-out: cubic-bezier(0.16, 1, 0.3, 1);
  --dur-fast: 180ms;
  --dur: 320ms;
  --dur-slow: 900ms;

  /* 层级 */
  --z-header: 50;
  --z-nav: 40;
  --z-skip: 100;
}

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

html {
  -webkit-text-size-adjust: 100%;
  scroll-behavior: smooth;
  scroll-padding-top: calc(var(--header-h) + 16px);
}

body {
  margin: 0;
  background: var(--paper);
  color: var(--ink);
  font-family: var(--font-sans);
  font-size: var(--text-base);
  line-height: 1.7;
  font-feature-settings: "palt" 0;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  text-rendering: optimizeLegibility;
}

/* 极轻的颗粒感，打破纯平底色 */
body::before {
  content: "";
  position: fixed;
  inset: 0;
  pointer-events: none;
  z-index: 0;
  opacity: 0.35;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='160' height='160'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='.9' numOctaves='2' stitchTiles='stitch'/%3E%3CfeColorMatrix values='0 0 0 0 0.05 0 0 0 0 0.1 0 0 0 0 0.11 0 0 0 0.05 0'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23n)'/%3E%3C/svg%3E");
}

main, .site-footer { position: relative; z-index: 1; }

img { display: block; max-width: 100%; height: auto; }
a { color: inherit; text-decoration: none; }
h1, h2, h3, h4, p, ul, ol, dl, dd, figure { margin: 0; }
ul, ol { padding: 0; list-style: none; }
button { font: inherit; color: inherit; }

h1, h2, h3, h4 { text-wrap: balance; }
.nowrap { white-space: nowrap; }
p { text-wrap: pretty; }

.num {
  font-family: "Geist", var(--font-sans);
  font-variant-numeric: tabular-nums;
  font-weight: 600;
  letter-spacing: -0.03em;
}
.num small {
  font-size: 0.42em;
  font-weight: 500;
  letter-spacing: 0;
  margin-left: 0.12em;
}

:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 3px;
  border-radius: 4px;
}

.skip-link {
  position: fixed;
  top: 12px;
  left: 12px;
  z-index: var(--z-skip);
  padding: 10px 16px;
  border-radius: 999px;
  background: var(--ink);
  color: var(--paper);
  transform: translateY(-160%);
  transition: transform var(--dur) var(--ease-out);
}
.skip-link:focus { transform: none; }

.container {
  width: 100%;
  max-width: calc(var(--container) + var(--gutter) * 2);
  margin-inline: auto;
  padding-inline: var(--gutter);
}

/* ---------- 按钮与链接 ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  height: 48px;
  padding: 0 24px;
  border: 0;
  border-radius: 999px;
  font-weight: 600;
  font-size: var(--text-base);
  letter-spacing: 0.02em;
  white-space: nowrap;
  cursor: pointer;
  transition: background-color var(--dur-fast) ease, transform var(--dur-fast) var(--ease-out), box-shadow var(--dur) var(--ease-out);
}
.btn--sm { height: 40px; padding: 0 18px; font-size: var(--text-sm); }
.btn--lg { height: 56px; padding: 0 32px; font-size: var(--text-md); }
.btn--block { width: 100%; }

.btn--primary {
  background: var(--accent);
  color: #fff;
  box-shadow: 0 8px 20px -10px rgba(14, 107, 112, 0.7);
}
.btn--primary:hover { background: var(--accent-deep); transform: translateY(-1px); }
.btn--primary:active { transform: translateY(1px) scale(0.98); }
.btn[disabled] { opacity: 0.6; cursor: progress; transform: none; }

.link-arrow {
  position: relative;
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-weight: 600;
  color: var(--ink);
  padding-block: 6px;
}
.link-arrow::after {
  content: "";
  width: 18px;
  height: 1.5px;
  background: currentColor;
  transition: width var(--dur) var(--ease-out);
}
.link-arrow:hover { color: var(--accent); }
.link-arrow:hover::after { width: 30px; }

.icon-btn {
  display: inline-grid;
  place-items: center;
  width: 48px;
  height: 48px;
  border: 1px solid var(--line-strong);
  border-radius: 999px;
  background: transparent;
  cursor: pointer;
  transition: background-color var(--dur-fast) ease, border-color var(--dur-fast) ease, transform var(--dur-fast) var(--ease-out);
}
.icon-btn svg { width: 20px; height: 20px; fill: none; stroke: currentColor; stroke-width: 1.6; stroke-linecap: round; stroke-linejoin: round; }
.icon-btn:hover { background: var(--ink); border-color: var(--ink); color: var(--paper); }
.icon-btn:active { transform: scale(0.95); }
.icon-btn[aria-disabled="true"] { opacity: 0.35; cursor: default; }
.icon-btn[aria-disabled="true"]:hover { background: transparent; border-color: var(--line-strong); color: inherit; }

/* ---------- 顶栏 ---------- */
.site-header {
  position: fixed;
  inset: 0 0 auto;
  z-index: var(--z-header);
  height: var(--header-h);
}
/* 毛玻璃放在伪元素上：backdrop-filter 写在 header 本身会让它成为
   fixed 子元素（移动端菜单）的包含块，菜单会塌成顶栏高度 */
.site-header::before {
  content: "";
  position: absolute;
  inset: 0;
  background: rgba(238, 241, 240, 0.82);
  backdrop-filter: saturate(1.4) blur(14px);
  -webkit-backdrop-filter: saturate(1.4) blur(14px);
  box-shadow: 0 1px 0 var(--line);
  opacity: 0;
  transition: opacity var(--dur) ease;
}
.site-header.is-scrolled::before { opacity: 1; }
.site-header__inner {
  position: relative;
  height: 100%;
  display: flex;
  align-items: center;
  gap: 32px;
}

.wordmark {
  display: inline-flex;
  flex-direction: column;
  line-height: 1;
  gap: 5px;
  flex-shrink: 0;
}
.wordmark__cn {
  font-size: 1.375rem;
  font-weight: 800;
  letter-spacing: 0.14em;
}
.wordmark__en {
  font-family: var(--font-mono);
  font-size: 0.625rem;
  letter-spacing: 0.3em;
  color: var(--mute);
}

.site-nav { margin-left: auto; }
.site-nav__list { display: flex; gap: 4px; }
.site-nav__list a {
  position: relative;
  display: block;
  padding: 8px 12px;
  font-size: 0.9375rem;
  font-weight: 500;
  color: var(--ink-soft);
  border-radius: 999px;
  transition: color var(--dur-fast) ease, background-color var(--dur-fast) ease;
}
.site-nav__list a:hover { color: var(--ink); background: rgba(14, 27, 29, 0.05); }
.site-nav__list a[aria-current="true"] { color: var(--ink); }
.site-nav__list a[aria-current="true"]::after {
  content: "";
  position: absolute;
  left: 50%;
  bottom: 2px;
  width: 4px;
  height: 4px;
  margin-left: -2px;
  border-radius: 50%;
  background: var(--accent);
}
.site-nav__mobile-extra { display: none; }

.site-header__actions { display: flex; align-items: center; gap: 20px; }
.site-header__tel {
  font-family: "Geist", var(--font-sans);
  font-variant-numeric: tabular-nums;
  font-weight: 500;
  font-size: 0.9375rem;
  color: var(--ink-soft);
}
.site-header__tel:hover { color: var(--accent); }

.nav-toggle {
  display: none;
  position: relative;
  width: 44px;
  height: 44px;
  border: 0;
  background: transparent;
  cursor: pointer;
}
.nav-toggle span {
  position: absolute;
  left: 11px;
  width: 22px;
  height: 1.5px;
  background: var(--ink);
  transition: transform var(--dur) var(--ease-out), top var(--dur) var(--ease-out);
}
.nav-toggle span:first-child { top: 17px; }
.nav-toggle span:last-child { top: 25px; }
.nav-toggle[aria-expanded="true"] span:first-child { top: 21px; transform: rotate(45deg); }
.nav-toggle[aria-expanded="true"] span:last-child { top: 21px; transform: rotate(-45deg); }

/* ---------- Hero ---------- */
.hero {
  position: relative;
  padding-top: calc(var(--header-h) + clamp(2rem, 1rem + 3vw, 4rem));
  padding-bottom: clamp(3rem, 2rem + 3vw, 5rem);
  overflow: hidden;
}
/* 右上角一束很淡的青色光，给页面一点空气感 */
.hero::before {
  content: "";
  position: absolute;
  top: -20%;
  right: -10%;
  width: 70vw;
  height: 90vh;
  background: radial-gradient(closest-side, rgba(14, 107, 112, 0.12), transparent 70%);
  pointer-events: none;
}
.hero__grid {
  position: relative;
  display: grid;
  grid-template-columns: minmax(0, 1.05fr) minmax(0, 1fr);
  gap: clamp(2rem, 1rem + 4vw, 6rem);
  align-items: center;
  min-height: min(calc(100dvh - var(--header-h) - 6rem), 720px);
}
.hero__title {
  font-size: var(--text-hero);
  font-weight: 700;
  line-height: 1.14;
  letter-spacing: 0; /* 中文标题不加负字距，方块字收紧会粘连 */
}
.reveal-line { display: block; overflow: hidden; padding-bottom: 0.06em; }
.reveal-line > span { display: inline-block; }
.hero__lede {
  margin-top: 28px;
  max-width: 28em;
  font-size: var(--text-lg);
  line-height: 1.7;
  color: var(--ink-soft);
}
.hero__actions {
  margin-top: 40px;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 16px 32px;
}

/* 素材墙：两列反向缓慢滚动 */
.hero__grid {
  min-height: min(calc(100vh - var(--header-h) - 6rem), 720px);
  min-height: min(calc(100dvh - var(--header-h) - 6rem), 720px);
}
.hero__wall {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
  height: min(calc(100vh - var(--header-h) - 5rem), 680px);
  height: min(calc(100dvh - var(--header-h) - 5rem), 680px);
  min-height: 460px;
}
.wall-col { display: flex; flex-direction: column; min-height: 0;height:800px; }
.wall-col__label {
  font-size: var(--text-sm);
  font-weight: 600;
  color: var(--ink-soft);
  padding: 0 4px 12px;
  display: flex;
  align-items: center;
  gap: 8px;
}
.wall-col__label::before {
  content: "";
  width: 14px;
  height: 1.5px;
  background: var(--accent);
}
.wall-col__viewport {
  position: relative;
  flex: 1;
  min-height: 0;
  overflow: hidden;
  border-radius: var(--r-card);
  -webkit-mask-image: linear-gradient(to bottom, transparent, #000 10%, #000 88%, transparent);
  mask-image: linear-gradient(to bottom, transparent, #000 10%, #000 88%, transparent);
}
.hero__wall { --wall-gap: 16px; }
.wall-col__track { display: flex; flex-direction: column; gap: var(--wall-gap); }
.wall-col__track li {
  border-radius: var(--r-media);
  overflow: hidden;
  background: var(--paper-deep);
  aspect-ratio: 4 / 3;
  box-shadow: var(--shadow-lift);
}
.wall-col__track img { width: 100%; height: 100%; object-fit: cover; }
.wall-col--down .wall-col__track img { filter: saturate(0.88) contrast(1.03); }

.js .wall-col__track.is-looping { animation: wall-up 70s linear infinite; }
.js .wall-col--down .wall-col__track.is-looping { animation-name: wall-down; animation-duration: 80s; }
.hero__wall:hover .wall-col__track,
.hero__wall.is-paused .wall-col__track { animation-play-state: paused; }
.hero__wall { position: relative; }
.wall-toggle {
  position: absolute;
  right: 8px;
  bottom: 8px;
  z-index: 2;
  display: none;
  align-items: center;
  gap: 6px;
  height: 32px;
  padding: 0 12px;
  border: 1px solid var(--line);
  border-radius: 999px;
  background: rgba(248, 250, 249, 0.9);
  font-size: 0.8125rem;
  font-weight: 500;
  color: var(--ink-soft);
  cursor: pointer;
  transition: background-color var(--dur-fast) ease, color var(--dur-fast) ease;
}
.wall-toggle:hover { background: var(--ink); color: var(--paper); }
.hero__wall.is-animated .wall-toggle { display: inline-flex; }

@keyframes wall-up { from { transform: translateY(0); } to { transform: translateY(calc(-50% - var(--wall-gap) / 2)); } }
@keyframes wall-down { from { transform: translateY(calc(-50% - var(--wall-gap) / 2)); } to { transform: translateY(0); } }

/* ---------- 成果数据 ---------- */
.proof { padding-bottom: clamp(2rem, 1rem + 3vw, 4rem); }
.proof__list {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  border-top: 1px solid var(--line-strong);
}
.proof__item {
  padding: 28px 24px 8px 0;
}
.proof__item + .proof__item { padding-left: 24px; border-left: 1px solid var(--line); }
.proof__item dt { font-size: var(--text-sm); color: var(--mute); }
.proof__item dd { display: flex; flex-direction: column; gap: 6px; margin-top: 8px; }
.proof__item .num { font-size: clamp(2.25rem, 1.6rem + 2vw, 3.5rem); line-height: 1; color: var(--ink); }
.proof__src { font-size: var(--text-sm); color: var(--accent); font-weight: 500; }

/* ---------- 通用区块 ---------- */
.section { padding-block: var(--section-y); }
.section-head { max-width: 44rem; margin-bottom: clamp(2.5rem, 2rem + 2vw, 4rem); }
.section-title {
  font-size: var(--text-section);
  font-weight: 700;
  line-height: 1.2;
  letter-spacing: 0;
}
.section-lede {
  margin-top: 16px;
  max-width: 36em;
  font-size: var(--text-md);
  color: var(--ink-soft);
}

/* ---------- 核心业务 ---------- */
.business__grid {
  display: grid;
  grid-template-columns: 1.25fr 1fr;
  gap: 20px;
  align-items: stretch;
}
.biz-col {
  display: flex;
  flex-direction: column;
  padding: clamp(1.75rem, 1rem + 2.5vw, 3.25rem);
  border-radius: var(--r-card);
  background: var(--surface);
  border: 1px solid var(--line);
}
.biz-col--school { background: var(--paper-deep); border-color: transparent; }
.biz-col__head {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 16px;
  padding-bottom: 24px;
  margin-bottom: 8px;
  border-bottom: 1px solid var(--line-strong);
}
.biz-col__head h3 { flex-shrink: 0; font-size: var(--text-xl); font-weight: 700; }
.biz-col__head p { color: var(--mute); }
.biz-list {
  flex: 1;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  grid-auto-rows: 1fr;   /* 两卡等高时，较矮一侧的行距均匀撑开，而不是在底部留白 */
  column-gap: 32px;
}
.biz-col--school .biz-list { grid-template-columns: 1fr; }
.biz-list li { padding: 20px 0; }
.biz-list li + li { border-top: 1px solid var(--line); }
.biz-col:not(.biz-col--school) .biz-list li:nth-child(2) { border-top: 0; }
.biz-list h4 { font-size: var(--text-md); font-weight: 600; }
.biz-list p { margin-top: 4px; font-size: 0.9375rem; color: var(--ink-soft); }
.biz-ip {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 4px 20px;
  margin-top: 28px;
  padding-inline: clamp(1.75rem, 1rem + 2.5vw, 3.25rem);   /* 与上方卡片内容左缘对齐 */
}
.biz-ip h3 { font-size: var(--text-md); font-weight: 700; }
.biz-ip p { font-size: 0.9375rem; color: var(--ink-soft); }

/* ---------- 行业优势 ---------- */
.advantage { background: var(--paper-deep); }
.advantage__grid {
  display: grid;
  grid-template-columns: minmax(0, 5fr) minmax(0, 7fr);
  gap: clamp(2rem, 1rem + 5vw, 7rem);
  align-items: start;
}
.advantage__head { position: sticky; top: calc(var(--header-h) + 40px); }
.pain-list { counter-reset: none; }
.pain {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(0, 1.25fr);
  gap: 32px;
  padding: 32px 0;
  border-bottom: 1px solid var(--line-strong);
}
.pain:first-child { padding-top: 0; }
.pain__problem {
  position: relative;
  align-self: start;
  justify-self: start;
  font-size: var(--text-lg);
  font-weight: 500;
  line-height: 1.5;
  color: var(--mute);
}
/* 悬停时把问题“划掉” */
.pain__problem::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  top: 0.78em;
  height: 1.5px;
  background: var(--accent);
  transform: scaleX(0);
  transform-origin: left;
  transition: transform 520ms var(--ease-out);
}
.pain:hover .pain__problem::after { transform: scaleX(1); }
.pain__answer h3 { font-size: var(--text-lg); font-weight: 700; }
.pain__answer p { margin-top: 8px; color: var(--ink-soft); }

/* ---------- 校企合作 ---------- */
.school__head { margin-bottom: clamp(2.5rem, 2rem + 2vw, 4rem); }
.honors {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, auto));
  justify-content: start;
  margin-top: 36px;
  border-top: 1px solid var(--line-strong);
}
.honors div { padding: 20px 48px 0 0; }
.honors div + div { padding-left: 48px; border-left: 1px solid var(--line); }
.honors dt { font-size: var(--text-sm); font-weight: 600; color: var(--accent); }
.honors dd { margin-top: 4px; font-size: var(--text-md); font-weight: 600; }

.gallery { position: relative; }
.gallery__track {
  /* 用 100% 而不是 100vw：vw 含滚动条宽度，会让首图比容器内容偏右 */
  --inset: max(var(--gutter), calc((100% - var(--container)) / 2));
  display: flex;
  gap: 20px;
  overflow-x: auto;
  scroll-snap-type: x mandatory;
  scroll-padding-inline: var(--inset);
  padding-inline: var(--inset);
  padding-bottom: 8px;
  scrollbar-width: none;
  overscroll-behavior-x: contain;
}
.gallery__track::-webkit-scrollbar { display: none; }
.gallery__track:focus-visible { outline-offset: -2px; }
.gallery__item {
  flex: 0 0 clamp(260px, 26vw, 380px);
  scroll-snap-align: start;
}
.gallery__item--wide { flex-basis: clamp(300px, 36vw, 520px); }
.gallery__item img {
  width: 100%;
  height: clamp(220px, 20vw, 320px);
  object-fit: cover;
  border-radius: var(--r-media);
  filter: saturate(0.88) contrast(1.03);
  transition: filter var(--dur) ease;
}
.gallery__item:hover img { filter: none; }
.gallery__item p { margin-top: 14px; font-size: 0.9375rem; color: var(--ink-soft); max-width: 30em; }
.gallery__item strong { display: block; color: var(--ink); font-weight: 600; }
.gallery__controls { display: flex; justify-content: flex-end; gap: 10px; margin-top: 24px; }

.partners {
  margin-top: clamp(3rem, 2rem + 3vw, 5rem);
  padding-top: 28px;
  border-top: 1px solid var(--line-strong);
  display: grid;
  grid-template-columns: 10rem 1fr;
  gap: 24px;
}
.partners__title { font-size: var(--text-base); font-weight: 600; }
.partners__list {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(12.5em, 1fr));   /* 最长校名 12 字，按 em 算才不会折行 */
  gap: 10px 24px;
  color: var(--ink-soft);
  font-size: 0.9375rem;
}

/* ---------- 项目案例 ---------- */
.cases { background: var(--paper-deep); }
.case-grid {
  display: grid;
  grid-template-columns: repeat(12, minmax(0, 1fr));
  gap: 20px;
}
.case {
  position: relative;
  display: flex;
  flex-direction: column;
  border-radius: var(--r-card);
  background: var(--surface);
  overflow: hidden;
  transition: transform var(--dur) var(--ease-out), box-shadow var(--dur) var(--ease-out);
}
.case:hover { transform: translateY(-3px); box-shadow: var(--shadow-lift); }
.case--a { grid-column: 1 / 8; grid-row: 1 / 3; }
.case--b { grid-column: 8 / 13; grid-row: 1; }
.case--c { grid-column: 8 / 13; grid-row: 2; }
.case--d { grid-column: 1 / 5; }
.case--e { grid-column: 5 / 9; }
.case--f { grid-column: 9 / 13; }

.case__media { aspect-ratio: 16 / 9; overflow: hidden; background: #E6EAE9; }
.case--a .case__media { aspect-ratio: 4 / 3; }
.case__media img { width: 100%; height: 100%; object-fit: cover; transition: transform 800ms var(--ease-out); }
.case:hover .case__media img { transform: scale(1.035); }
/* 小越网校原图四周是灰色暗角，放大取中间的亮部 */
.case--f .case__media img { transform: scale(1.7); }
.case--f:hover .case__media img { transform: scale(1.76); }

.case__body { display: flex; flex-direction: column; flex: 1; padding: 24px 26px 26px; }
.case--a .case__body { padding: 32px 36px 36px; }
.case__client { font-size: var(--text-sm); font-weight: 600; color: var(--accent); }
.case__title { margin-top: 4px; font-size: var(--text-md); font-weight: 700; line-height: 1.45; }
.case--a .case__title { font-size: var(--text-xl); }
.case__desc { margin-top: 10px; font-size: 0.9375rem; color: var(--ink-soft); }
.case__metric {
  margin-top: auto;
  padding-top: 20px;
  display: flex;
  align-items: baseline;
  gap: 10px;
  font-size: var(--text-sm);
  color: var(--mute);
}
.case__metric .num { font-size: 2rem; line-height: 1; color: var(--ink); }
.case--a .case__metric .num { font-size: 3rem; }
.case__metrics { margin-top: auto; display: flex; flex-wrap: wrap; gap: 8px 32px; }
.case__metrics .case__metric { margin-top: 0; }

.tags { display: flex; flex-wrap: wrap; gap: 6px; margin-top: 18px; }
.tags li {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  padding: 4px 10px;
  border-radius: 6px;
  background: var(--paper);
  color: var(--ink-soft);
}

/* 双星没有项目图，用深色文字格承担视觉变化 */
.case--ink { background: var(--night); color: var(--on-night); }
.case--ink .case__body { padding: 32px; justify-content: flex-start; }
.case--ink .case__client { color: var(--accent-on-night); }
.case--ink .case__title { font-size: var(--text-lg); }
.case--ink .case__desc,
.case--ink .case__metric { color: var(--on-night-mute); }
.case--ink .case__metric .num { color: #fff; }
.case--ink .case__metrics { padding-top: 24px; }
.case--ink .tags li { background: rgba(255, 255, 255, 0.08); color: var(--on-night); }

/* ---------- 公司简介 ---------- */
.about__grid {
  display: grid;
  grid-template-columns: minmax(0, 7fr) minmax(0, 5fr);
  gap: clamp(2.5rem, 1rem + 5vw, 7rem);
  align-items: start;
}
.about__statement {
  margin-top: 24px;
  font-size: var(--text-xl);
  font-weight: 500;
  line-height: 1.65;
  color: var(--ink);
}
.facts {
  display: grid;
  grid-template-columns: repeat(3, auto);
  justify-content: start;
  gap: 16px clamp(2rem, 1rem + 3vw, 4rem);
  margin-top: 40px;
}
.facts dt { font-size: var(--text-sm); color: var(--mute); }
.facts dd { font-size: clamp(2rem, 1.5rem + 1.5vw, 2.75rem); line-height: 1.1; margin-top: 4px; }

.values { padding-top: 12px; }
.values__title { font-size: var(--text-sm); font-weight: 600; color: var(--mute); padding-bottom: 16px; }
.values__list li {
  padding: 24px 0;
  border-top: 1px solid var(--line-strong);
  font-size: var(--text-lg);
  line-height: 1.6;
  color: var(--mute);
}
.values__list strong { color: var(--ink); font-weight: 700; }

/* ---------- 联系我们（深色收尾，与页脚连成一体） ---------- */
.contact {
  background: var(--night);
  color: var(--on-night);
  padding-block: var(--section-y);
}
.contact .section-lede { color: var(--on-night-mute); }
.contact__grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(0, 1fr);
  gap: clamp(2.5rem, 1rem + 5vw, 7rem);
  align-items: start;
}
.contact__list { margin-top: 40px; display: grid; gap: 18px; }
.contact__list div { display: grid; grid-template-columns: 4rem 1fr; gap: 16px; align-items: baseline; }
.contact__list dt { font-size: var(--text-sm); color: var(--on-night-mute); }
.contact__list dd { font-size: var(--text-md); }
.contact__list a {
  text-decoration: underline;
  text-decoration-color: rgba(231, 238, 237, 0.3);
  text-underline-offset: 5px;
  transition: color var(--dur-fast) ease, text-decoration-color var(--dur-fast) ease;
}
.contact__list a:hover { color: var(--accent-on-night); text-decoration-color: var(--accent-on-night); }

.qr-list { display: flex; gap: 20px; margin-top: 40px; }
.qr-list figure { text-align: center; }
.qr-list img { width: 104px; height: 104px; border-radius: 10px; background: #fff; padding: 6px; }
.qr-list figcaption { margin-top: 8px; font-size: 0.8125rem; color: var(--on-night-mute); }

.lead-form {
  position: relative;
  display: grid;
  gap: 22px;
  padding: clamp(1.5rem, 1rem + 2vw, 2.5rem);
  border-radius: var(--r-card);
  background: var(--night-2);
  border: 1px solid rgba(231, 238, 237, 0.08);
}
.field { position: relative; display: grid; gap: 8px; }
.field label { font-size: 0.9375rem; font-weight: 500; color: var(--on-night); }
.field label span { color: var(--accent-on-night); }
.field input,
.field textarea {
  width: 100%;
  padding: 14px 16px;
  border-radius: var(--r-input);
  border: 1px solid rgba(231, 238, 237, 0.2);
  background: rgba(255, 255, 255, 0.04);
  color: var(--on-night);
  font: inherit;
  transition: border-color var(--dur-fast) ease, background-color var(--dur-fast) ease;
}
.field textarea { resize: vertical; min-height: 120px; }
.field input:hover,
.field textarea:hover { border-color: rgba(231, 238, 237, 0.35); }
.field input:focus,
.field textarea:focus {
  outline: none;
  border-color: var(--accent-on-night);
  background: rgba(255, 255, 255, 0.07);
  box-shadow: 0 0 0 3px rgba(143, 207, 199, 0.18);
}
.field [aria-invalid="true"] { border-color: var(--danger-on-night); }
.field__hint { font-size: 0.8125rem; color: var(--on-night-mute); }
.field__error { font-size: 0.8125rem; color: var(--danger-on-night); min-height: 0; }
.field__error:empty { position: absolute; }
.contact .btn--primary { background: var(--accent-on-night); color: var(--night); box-shadow: none; }
.contact .btn--primary:hover { background: #A9DDD6; }
.contact :focus-visible { outline-color: var(--accent-on-night); }
.lead-form__status { font-size: 0.9375rem; color: var(--accent-on-night); }
.lead-form__status:empty { position: absolute; }
.lead-form__status.is-error { color: var(--danger-on-night); }

/* ---------- 页脚 ---------- */
.site-footer {
  background: var(--night);
  color: var(--on-night-mute);
  font-size: var(--text-sm);
}
.site-footer__inner {
  display: grid;
  grid-template-columns: auto 1fr auto;
  align-items: center;
  gap: 32px;
  padding-block: 40px 48px;
  border-top: 1px solid rgba(231, 238, 237, 0.1);
}
.wordmark--footer .wordmark__cn { color: var(--on-night); font-size: 1.125rem; }
.wordmark--footer .wordmark__en { color: var(--on-night-mute); }
.site-footer__nav { display: flex; flex-wrap: wrap; gap: 8px 28px; justify-content: center; }
.site-footer a { transition: color var(--dur-fast) ease; }
.site-footer a:hover { color: var(--on-night); }
.site-footer__legal { text-align: right; display: grid; gap: 4px; }
.site-footer__legal p { display: flex; flex-wrap: wrap; gap: 4px 16px; justify-content: flex-end; }
.site-footer :focus-visible { outline-color: var(--accent-on-night); }

/* ---------- 进场动效（仅在 JS 可用且未要求减少动效时启用） ---------- */
.js [data-reveal] {
  opacity: 0;
  transform: translateY(18px);
  transition: opacity var(--dur-slow) var(--ease-out), transform var(--dur-slow) var(--ease-out);
  transition-delay: var(--delay, 0ms);
}
.js [data-reveal].is-visible { opacity: 1; transform: none; }

.js .reveal-line > span {
  transform: translateY(105%);
  animation: line-up 1100ms var(--ease-out) forwards;
}
.js .reveal-line:nth-child(2) > span { animation-delay: 120ms; }
.js .hero__lede,
.js .hero__actions,
.js .hero__wall { opacity: 0; animation: fade-up 1000ms var(--ease-out) forwards; }
.js .hero__lede { animation-delay: 300ms; }
.js .hero__actions { animation-delay: 420ms; }
.js .hero__wall { animation-delay: 200ms; }

@keyframes line-up { to { transform: none; } }
@keyframes fade-up { from { opacity: 0; transform: translateY(16px); } to { opacity: 1; transform: none; } }

/* ---------- 响应式 ---------- */
@media (max-width: 1240px) {
  .site-header__tel { display: none; }
}

@media (max-width: 1080px) {
  .nav-toggle { display: inline-block; }
  .site-header__actions { margin-left: auto; }
  /* 触屏尺寸下扩大小链接的点击区域，负外边距抵消，排版不变 */
  .contact__list a,
  .site-footer__nav a,
  .site-footer__legal a { display: inline-block; padding-block: 10px; margin-block: -10px; }
  .site-header__actions .btn { display: none; }
  .site-nav {
    position: fixed;
    inset: var(--header-h) 0 0;
    z-index: var(--z-nav);
    display: flex;
    flex-direction: column;
    gap: 32px;   /* 按钮行紧跟列表，保证固定间距；不再靠 space-between 推到底部 */
    padding: 16px var(--gutter) max(32px, calc(env(safe-area-inset-bottom) + 20px));
    overflow-y: auto;   /* 矮屏（如 320×568）内容放不下时可以滚动，不被截断 */
    overscroll-behavior: contain;
    background: var(--paper);
    visibility: hidden;
    opacity: 0;
    transform: translateY(-8px);
    transition: opacity var(--dur) var(--ease-out), transform var(--dur) var(--ease-out), visibility 0s linear var(--dur);
  }
  .site-nav.is-open {
    visibility: visible;
    opacity: 1;
    transform: none;
    transition-delay: 0s;
  }
  .site-nav__list { flex-shrink: 0; flex-direction: column; gap: 0; }
  .site-nav__list a {
    padding: clamp(12px, 2.2vh, 16px) 0;   /* 矮屏收紧行高 */
    font-size: 1.375rem;
    font-weight: 600;
    color: var(--ink);
    border-radius: 0;
    border-bottom: 1px solid var(--line);
  }
  .site-nav__list a:hover { background: none; color: var(--accent); }
  .site-nav__list a[aria-current="true"] { color: var(--accent); }
  .site-nav__list a[aria-current="true"]::after { display: none; }
  .site-nav__mobile-extra { flex-shrink: 0; display: flex; align-items: center; gap: 20px; }
  .site-nav__mobile-extra .btn { box-shadow: none; }
  .site-nav__tel { font-family: "Geist", var(--font-sans); font-weight: 500; color: var(--ink-soft); }
  .site-header.is-menu-open { background: var(--paper); box-shadow: 0 1px 0 var(--line); }

  .hero__grid { grid-template-columns: 1fr; min-height: 0; }
  .hero__wall { height: 420px; min-height: 0; }
  .advantage__grid,
  .about__grid,
  .contact__grid { grid-template-columns: 1fr; }
  .advantage__head { position: static; }
  .business__grid { grid-template-columns: 1fr; }
  .case--a { grid-column: 1 / -1; grid-row: auto; }
  .case--b,
  .case--c { grid-column: span 6; grid-row: auto; }
  .case--d,
  .case--e,
  .case--f { grid-column: span 4; }
  .case--a .case__media { aspect-ratio: 16 / 9; }
}

@media (max-width: 760px) {
  :root { --header-h: 64px; }
  .hero__wall { height: 340px; gap: 12px; }
  .hero__wall { --wall-gap: 12px; }
  .proof__list { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .proof__item,
  .proof__item + .proof__item { padding: 20px 12px 16px 0; border-left: 0; }
  .proof__item:nth-child(even) { padding-left: 16px; border-left: 1px solid var(--line); }
  .proof__item:nth-child(n + 3) { border-top: 1px solid var(--line); }
  .biz-list { grid-template-columns: 1fr; grid-auto-rows: auto; }
  .honors { grid-template-columns: 1fr; }
  .honors div { padding-right: 0; }
  .honors div + div { padding-left: 0; border-left: 0; margin-top: 20px; border-top: 1px solid var(--line); }
  .biz-col:not(.biz-col--school) .biz-list li:nth-child(2) { border-top: 1px solid var(--line); }
  .pain { grid-template-columns: 1fr; gap: 12px; }
  .case-grid { grid-template-columns: 1fr; }
  .case--a, .case--b, .case--c, .case--d, .case--e, .case--f { grid-column: 1 / -1; }
  .case--a .case__body { padding: 24px 26px 26px; }
  .case--a .case__metric .num { font-size: 2.5rem; }
  .gallery__item,
  .gallery__item--wide { flex-basis: 78vw; }
  .partners { grid-template-columns: 1fr; gap: 16px; }
  .partners__list { gap: 8px 16px; font-size: 0.875rem; }
  .facts { grid-template-columns: repeat(3, 1fr); gap: 16px; }
  .qr-list img { width: 92px; height: 92px; }
  .site-footer__inner { grid-template-columns: 1fr; text-align: left; gap: 20px; }
  .site-footer__nav { justify-content: flex-start; gap: 8px 20px; }
  .site-footer__legal { text-align: left; }
  .site-footer__legal p { justify-content: flex-start; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
  .js .wall-col__track.is-looping { animation: none; }
  .js [data-reveal] { opacity: 1; transform: none; }
}