/* ==========================================================================
   允旭环保 · 企业官网样式表
   设计方向：简约现代（大量留白 / 细线分割 / 单一强调色 / 克制圆角）
   结构：1. 设计变量  2. 基础重置  3. 通用组件  4. 页头  5. 首屏
        6. 服务行业  7. 通用区块  8. 解决方案  9. 案例  10. 关于 / 数据
        11. 流程  12. 常见问题  13. CTA  14. 联系  15. 页脚  16. 动效 / 响应式
   ========================================================================== */

/* -------- 1. 设计变量（改这里即可整体换色） -------- */
:root {
  --ink: #0d1117;
  --ink-soft: #1c2530;
  --muted: #5f6b78;
  --muted-2: #8a95a1;
  --line: #e5e6e0;
  --line-strong: #d3d5cd;
  --bg: #fbfbf8;
  --surface: #ffffff;
  --surface-2: #f4f4ef;

  --accent: #0e6f57;
  --accent-strong: #095341;
  --accent-soft: #e6f1ed;

  --radius-sm: 10px;
  --radius: 16px;
  --radius-lg: 24px;

  --shadow-sm: 0 1px 2px rgba(13, 17, 23, .04);
  --shadow: 0 12px 32px -12px rgba(13, 17, 23, .14);
  --shadow-lg: 0 32px 64px -24px rgba(13, 17, 23, .22);

  --container: 1180px;
  --gutter: 24px;
  --header-h: 72px;

  --ease: cubic-bezier(.22, .61, .36, 1);
  --font: "Inter", -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC",
          "Hiragino Sans GB", "Microsoft YaHei", "Source Han Sans SC", "Noto Sans SC", sans-serif;
}

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

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

body {
  margin: 0;
  font-family: var(--font);
  font-size: 16px;
  line-height: 1.7;
  color: var(--ink-soft);
  background: var(--bg);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  font-feature-settings: "tnum" 0;
}

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

h1, h2, h3 { color: var(--ink); font-weight: 600; letter-spacing: -.02em; line-height: 1.25; }
h1 { letter-spacing: -.035em; }
h2 { font-size: clamp(28px, 3.4vw, 42px); }
h3 { font-size: 19px; letter-spacing: -.01em; }

::selection { background: var(--accent); color: #fff; }

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

.skip-link {
  position: absolute;
  top: -100px;
  left: 16px;
  z-index: 200;
  padding: 10px 16px;
  background: var(--ink);
  color: #fff;
  border-radius: 8px;
  transition: top .2s var(--ease);
}
.skip-link:focus { top: 12px; }

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

/* -------- 3. 通用组件 -------- */
.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  margin-bottom: 18px;
  font-size: 13px;
  font-weight: 600;
  letter-spacing: .08em;
  text-transform: uppercase;
  color: var(--accent);
}

.eyebrow .dot {
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--accent);
  box-shadow: 0 0 0 4px var(--accent-soft);
}

.accent { color: var(--accent); }
.nb { white-space: nowrap; }

.btn {
  --btn-bg: var(--ink);
  --btn-fg: #fff;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 11px 22px;
  border: 1px solid transparent;
  border-radius: 999px;
  background: var(--btn-bg);
  color: var(--btn-fg);
  font-size: 15px;
  font-weight: 500;
  white-space: nowrap;
  cursor: pointer;
  transition: transform .2s var(--ease), box-shadow .2s var(--ease),
              background-color .2s var(--ease), border-color .2s var(--ease);
}

.btn:hover { transform: translateY(-1px); box-shadow: var(--shadow); }
.btn:active { transform: translateY(0); box-shadow: none; }

.btn-primary { --btn-bg: var(--ink); --btn-fg: #fff; }
.btn-primary:hover { --btn-bg: var(--accent-strong); }

.btn-lg { padding: 14px 28px; font-size: 15.5px; }

.btn-ghost {
  --btn-bg: transparent;
  --btn-fg: var(--ink);
  border-color: var(--line-strong);
}
.btn-ghost:hover { --btn-bg: #fff; border-color: var(--ink); }

/* -------- 4. 页头 -------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: color-mix(in srgb, var(--bg) 82%, transparent);
  backdrop-filter: saturate(180%) blur(14px);
  -webkit-backdrop-filter: saturate(180%) blur(14px);
  border-bottom: 1px solid transparent;
  transition: border-color .25s var(--ease), background-color .25s var(--ease);
}

.site-header.is-scrolled {
  border-bottom-color: var(--line);
  background: color-mix(in srgb, var(--bg) 92%, transparent);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 32px;
  height: var(--header-h);
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  color: var(--accent);
  font-weight: 600;
}

.brand-mark { width: 30px; height: 30px; flex: none; }

.brand-name {
  font-size: 17px;
  letter-spacing: -.01em;
  color: var(--ink);
}

.nav {
  display: flex;
  align-items: center;
  gap: 4px;
}

.nav > a {
  position: relative;
  padding: 8px 14px;
  border-radius: 8px;
  font-size: 14.5px;
  color: var(--muted);
  transition: color .2s var(--ease), background-color .2s var(--ease);
}

.nav > a:hover { color: var(--ink); background: rgba(13, 17, 23, .04); }

.nav > a.is-active { color: var(--ink); font-weight: 500; }

.nav > a.is-active::after {
  content: "";
  position: absolute;
  left: 14px;
  right: 14px;
  bottom: 1px;
  height: 2px;
  border-radius: 2px;
  background: var(--accent);
}

.nav-cta { margin-left: 12px; padding: 9px 20px; font-size: 14.5px; }
.nav-cta::after { display: none; }
.nav-cta:hover { background: var(--accent-strong); color: #fff; }

.nav-toggle {
  display: none;
  width: 42px;
  height: 42px;
  padding: 0;
  border: 1px solid var(--line);
  border-radius: 10px;
  background: var(--surface);
  cursor: pointer;
}

.nav-toggle span {
  display: block;
  width: 18px;
  height: 1.5px;
  margin: 4px auto;
  background: var(--ink);
  transition: transform .25s var(--ease), opacity .2s var(--ease);
}

.nav-toggle[aria-expanded="true"] span:nth-child(1) { transform: translateY(5.5px) rotate(45deg); }
.nav-toggle[aria-expanded="true"] span:nth-child(2) { opacity: 0; }
.nav-toggle[aria-expanded="true"] span:nth-child(3) { transform: translateY(-5.5px) rotate(-45deg); }

/* -------- 5. 首屏 -------- */
.hero {
  position: relative;
  overflow: hidden;
  padding: clamp(56px, 8vw, 104px) 0 clamp(64px, 8vw, 112px);
}

.hero-bg {
  position: absolute;
  inset: 0;
  pointer-events: none;
  background:
    radial-gradient(60% 55% at 78% 18%, rgba(14, 111, 87, .10), transparent 70%),
    radial-gradient(45% 45% at 8% 0%, rgba(13, 17, 23, .05), transparent 70%);
}

.hero-bg::after {
  content: "";
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(to right, rgba(13, 17, 23, .045) 1px, transparent 1px),
    linear-gradient(to bottom, rgba(13, 17, 23, .045) 1px, transparent 1px);
  background-size: 72px 72px;
  mask-image: radial-gradient(70% 60% at 50% 30%, #000 30%, transparent 78%);
  -webkit-mask-image: radial-gradient(70% 60% at 50% 30%, #000 30%, transparent 78%);
  opacity: .8;
}

.hero-inner {
  position: relative;
  display: grid;
  grid-template-columns: 1.05fr .95fr;
  align-items: center;
  gap: clamp(32px, 5vw, 72px);
}

.hero-title {
  font-size: clamp(36px, 5.4vw, 64px);
  line-height: 1.14;
  letter-spacing: -.04em;
  margin-bottom: 22px;
}

.hero-lead {
  max-width: 34em;
  font-size: clamp(15.5px, 1.25vw, 17.5px);
  color: var(--muted);
  line-height: 1.85;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 34px;
}

.hero-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-top: 30px;
}

.hero-tags li {
  padding: 5px 12px;
  font-size: 12.5px;
  color: var(--muted);
  background: rgba(255, 255, 255, .7);
  border: 1px solid var(--line);
  border-radius: 999px;
}

/* 首屏配图 */
.hero-media {
  position: relative;
  margin: 0;
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-lg);
  transform: rotate(-1.2deg);
}

.hero-media img {
  display: block;
  width: 100%;
  aspect-ratio: 4 / 3;
  object-fit: cover;
}

.hero-media figcaption {
  position: absolute;
  left: 12px;
  bottom: 12px;
  max-width: calc(100% - 24px);
  padding: 9px 14px;
  font-size: 12.5px;
  letter-spacing: .02em;
  color: rgba(255, 255, 255, .94);
  background: rgba(13, 17, 23, .66);
  border: 1px solid rgba(255, 255, 255, .14);
  border-radius: 999px;
  box-shadow: 0 8px 20px -8px rgba(0, 0, 0, .5);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
}

/* -------- 6. 服务行业 -------- */
.industry-strip {
  padding: 26px 0;
  border-block: 1px solid var(--line);
}

.industry-inner {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 14px 28px;
}

.industry-label {
  padding-right: 24px;
  font-size: 12px;
  font-weight: 600;
  letter-spacing: .08em;
  color: var(--muted-2);
  border-right: 1px solid var(--line);
}

.industry-list {
  display: flex;
  flex-wrap: wrap;
  gap: 10px 26px;
  font-size: 14.5px;
  color: var(--muted);
}

.industry-list li {
  position: relative;
  padding-left: 14px;
  transition: color .2s var(--ease);
}

.industry-list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: .62em;
  width: 4px;
  height: 4px;
  border-radius: 1px;
  background: var(--accent);
  opacity: .6;
}

.industry-list li:hover { color: var(--ink); }

/* -------- 7. 通用区块 -------- */
.section { padding: clamp(64px, 8vw, 112px) 0; }
.section-tint { background: var(--surface-2); border-block: 1px solid var(--line); }

.section-head { max-width: 660px; margin-bottom: clamp(36px, 4vw, 56px); }

.section-head h2 { margin-bottom: 16px; }

.section-desc {
  font-size: 15.5px;
  line-height: 1.85;
  color: var(--muted);
}

.section-head--row {
  display: flex;
  align-items: flex-end;
  justify-content: space-between;
  gap: 40px;
  max-width: none;
}

.section-desc--side { max-width: 320px; flex: none; font-size: 14.5px; }

.grid { display: grid; gap: 20px; }
.grid-2 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
.grid-3 { grid-template-columns: repeat(3, minmax(0, 1fr)); }

/* -------- 8. 解决方案卡片 -------- */
.card {
  position: relative;
  display: flex;
  flex-direction: column;
  padding: 30px;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  transition: transform .3s var(--ease), box-shadow .3s var(--ease), border-color .3s var(--ease);
}

.card:hover {
  transform: translateY(-4px);
  border-color: var(--line-strong);
  box-shadow: var(--shadow);
}

.card-icon {
  display: grid;
  place-items: center;
  width: 42px;
  height: 42px;
  margin-bottom: 20px;
  color: var(--accent);
  background: var(--accent-soft);
  border-radius: 11px;
}

.card-icon svg {
  width: 21px;
  height: 21px;
  fill: none;
  stroke: currentColor;
  stroke-width: 1.6;
  stroke-linecap: round;
  stroke-linejoin: round;
}

.card h3 { margin-bottom: 10px; }

.card > p { font-size: 14.5px; color: var(--muted); line-height: 1.8; }

.card-list {
  display: grid;
  gap: 8px;
  margin: 20px 0 24px;
  font-size: 13.5px;
  color: var(--muted);
}

.card-list li {
  position: relative;
  padding-left: 18px;
}

.card-list li::before {
  content: "";
  position: absolute;
  left: 2px;
  top: .62em;
  width: 5px;
  height: 5px;
  border-radius: 50%;
  background: var(--accent);
  opacity: .55;
}

.card-link {
  margin-top: auto;
  font-size: 14px;
  font-weight: 500;
  color: var(--accent);
  transition: gap .2s var(--ease), color .2s var(--ease);
}

.card-link span { display: inline-block; transition: transform .2s var(--ease); }
.card-link:hover { color: var(--accent-strong); }
.card-link:hover span { transform: translateX(4px); }

/* -------- 9. 案例卡片 -------- */
.case {
  display: flex;
  flex-direction: column;
  overflow: hidden;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  transition: transform .3s var(--ease), box-shadow .3s var(--ease), border-color .3s var(--ease);
}

.case:hover {
  transform: translateY(-4px);
  border-color: var(--line-strong);
  box-shadow: var(--shadow);
}

.case-cover {
  position: relative;
  height: 196px;
  overflow: hidden;
  background: var(--surface-2);
}

.case-cover img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform .7s var(--ease);
}

.case:hover .case-cover img { transform: scale(1.04); }

.case-cover::after {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(to top, rgba(13, 17, 23, .28), transparent 55%);
  pointer-events: none;
}

.case-industry {
  position: absolute;
  z-index: 1;
  top: 14px;
  left: 14px;
  padding: 5px 12px;
  font-size: 11.5px;
  font-weight: 500;
  letter-spacing: .02em;
  color: var(--ink);
  background: rgba(255, 255, 255, .86);
  border-radius: 999px;
  backdrop-filter: blur(4px);
}

.case-body { display: flex; flex-direction: column; flex: 1; padding: 24px; }

.case-body h3 { font-size: 16.5px; line-height: 1.5; margin-bottom: 10px; }

.case-client { font-size: 13px; color: var(--muted-2); }

.case-metric {
  display: flex;
  align-items: baseline;
  gap: 10px;
  margin-top: auto;
  padding-top: 20px;
}

.case-metric strong {
  font-size: 30px;
  font-weight: 600;
  letter-spacing: -.035em;
  color: var(--accent);
  font-variant-numeric: tabular-nums;
}

.case-metric span { font-size: 12.5px; color: var(--muted); }

/* -------- 10. 关于 / 数据 -------- */
.about-grid {
  display: grid;
  grid-template-columns: 1.05fr .95fr;
  gap: clamp(40px, 6vw, 88px);
  align-items: start;
}

.about-copy h2 { margin-bottom: 22px; }

.about-copy p {
  font-size: 15.5px;
  line-height: 1.9;
  color: var(--muted);
  margin-bottom: 16px;
}

.about-points {
  display: grid;
  gap: 14px;
  margin-top: 28px;
  padding-top: 26px;
  border-top: 1px solid var(--line);
}

.about-points li {
  position: relative;
  padding-left: 22px;
  font-size: 14px;
  color: var(--muted);
}

.about-points li::before {
  content: "";
  position: absolute;
  left: 0;
  top: .7em;
  width: 6px;
  height: 6px;
  border-radius: 1px;
  background: var(--accent);
}

.about-points strong {
  display: inline-block;
  margin-right: 10px;
  font-weight: 600;
  color: var(--ink);
}

.about-media {
  margin: 0;
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: var(--radius);
}

.about-media img {
  display: block;
  width: 100%;
  aspect-ratio: 1 / 1;
  object-fit: cover;
}

.stats {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  background: var(--line);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  overflow: hidden;
}

.stats--row {
  grid-template-columns: repeat(4, minmax(0, 1fr));
  margin-top: clamp(40px, 5vw, 64px);
}

.stat {
  display: flex;
  flex-direction: column;
  gap: 6px;
  padding: 32px 26px;
  background: var(--surface);
}

.stat-num {
  font-size: clamp(34px, 3.6vw, 44px);
  font-weight: 600;
  line-height: 1.1;
  letter-spacing: -.04em;
  color: var(--ink);
  font-variant-numeric: tabular-nums;
}

.stat-label { font-size: 13px; color: var(--muted); }

/* -------- 11. 流程 -------- */
.steps {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 20px;
  counter-reset: step;
}

.step {
  position: relative;
  padding-top: 26px;
  border-top: 1px solid var(--line-strong);
}

.step::before {
  content: "";
  position: absolute;
  top: -3px;
  left: 0;
  width: 5px;
  height: 5px;
  border-radius: 50%;
  background: var(--accent);
}

.step-num {
  display: block;
  margin-bottom: 14px;
  font-size: 12px;
  font-weight: 600;
  letter-spacing: .1em;
  color: var(--accent);
}

.step h3 { font-size: 17px; margin-bottom: 8px; }

.step p { font-size: 14px; line-height: 1.8; color: var(--muted); }

/* -------- 12. 常见问题 -------- */
.faq-grid {
  display: grid;
  grid-template-columns: .8fr 1.2fr;
  gap: clamp(36px, 5vw, 72px);
  align-items: start;
}

.faq-head { position: sticky; top: calc(var(--header-h) + 24px); }

.faq-head h2 { margin-bottom: 16px; }

.faq-head .section-desc { margin-bottom: 24px; }

.faq-list { border-top: 1px solid var(--line-strong); }

.faq-item { border-bottom: 1px solid var(--line); }

.faq-item summary {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
  padding: 22px 2px;
  font-size: 16px;
  font-weight: 500;
  color: var(--ink);
  cursor: pointer;
  list-style: none;
}

.faq-item summary::-webkit-details-marker { display: none; }

.faq-item summary::after {
  content: "";
  flex: none;
  width: 10px;
  height: 10px;
  margin-right: 4px;
  border-right: 1.5px solid var(--muted-2);
  border-bottom: 1.5px solid var(--muted-2);
  transform: rotate(45deg) translateY(-2px);
  transition: transform .25s var(--ease);
}

.faq-item[open] summary::after { transform: rotate(-135deg) translateY(-2px); }

.faq-item summary:hover { color: var(--accent); }

.faq-item p {
  padding: 0 0 24px 2px;
  max-width: 56em;
  font-size: 14.5px;
  line-height: 1.9;
  color: var(--muted);
}

/* -------- 13. CTA -------- */
.cta-band {
  padding: clamp(28px, 4vw, 40px) 0;
  background: var(--bg);
}

.cta-inner {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 28px;
  padding: clamp(32px, 4vw, 52px);
  background: var(--ink);
  border-radius: var(--radius-lg);
  color: #fff;
}

.cta-inner h2 {
  margin-bottom: 10px;
  color: #fff;
  font-size: clamp(22px, 2.6vw, 30px);
}

.cta-inner p { font-size: 14.5px; color: rgba(255, 255, 255, .66); }

.cta-inner .btn {
  --btn-bg: #fff;
  --btn-fg: var(--ink);
  flex: none;
}
.cta-inner .btn:hover { --btn-bg: var(--accent-soft); }

/* -------- 14. 联系 -------- */
.contact-grid {
  display: grid;
  grid-template-columns: .9fr 1.1fr;
  gap: clamp(40px, 6vw, 80px);
  align-items: start;
}

.contact-copy h2 { margin-bottom: 16px; }

.contact-list {
  display: grid;
  gap: 18px;
  margin-top: 32px;
  padding-top: 28px;
  border-top: 1px solid var(--line);
}

.contact-list > div { display: grid; grid-template-columns: 64px 1fr; gap: 12px; }

.contact-list dt { font-size: 13px; color: var(--muted-2); }

.contact-list dd { font-size: 15px; color: var(--ink-soft); }
.contact-list dd a { border-bottom: 1px solid transparent; transition: border-color .2s var(--ease); }
.contact-list dd a:hover { border-bottom-color: var(--accent); color: var(--accent); }

.muted-note { font-size: 12.5px; color: var(--muted-2); }

.contact-extra {
  margin-top: 30px;
  padding: 20px 22px;
  background: var(--surface-2);
  border: 1px solid var(--line);
  border-radius: var(--radius-sm);
}

.contact-extra strong {
  display: block;
  margin-bottom: 6px;
  font-size: 13px;
  font-weight: 600;
  color: var(--ink);
}

.contact-extra p { font-size: 13.5px; line-height: 1.8; color: var(--muted); }

.contact-form {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 18px 20px;
  padding: clamp(24px, 3vw, 34px);
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  box-shadow: var(--shadow-sm);
}

.field { display: flex; flex-direction: column; gap: 7px; }
.field--full { grid-column: 1 / -1; }

.field label { font-size: 13px; font-weight: 500; color: var(--ink); }
.req { color: var(--accent); }

.field input,
.field textarea,
.field select {
  width: 100%;
  padding: 11px 14px;
  font: inherit;
  font-size: 14.5px;
  color: var(--ink);
  background: var(--bg);
  border: 1px solid var(--line);
  border-radius: var(--radius-sm);
  transition: border-color .2s var(--ease), background-color .2s var(--ease), box-shadow .2s var(--ease);
}

.field select {
  appearance: none;
  -webkit-appearance: none;
  padding-right: 38px;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='8' viewBox='0 0 12 8'%3E%3Cpath d='M1 1l5 5 5-5' fill='none' stroke='%235f6b78' stroke-width='1.5' stroke-linecap='round'/%3E%3C/svg%3E");
  background-repeat: no-repeat;
  background-position: right 14px center;
  cursor: pointer;
}

.field textarea { resize: vertical; min-height: 96px; }

.field input::placeholder,
.field textarea::placeholder { color: var(--muted-2); }

.field input:focus,
.field textarea:focus,
.field select:focus {
  outline: none;
  background-color: #fff;
  border-color: var(--accent);
  box-shadow: 0 0 0 3px rgba(14, 111, 87, .12);
}

.field input[aria-invalid="true"] {
  border-color: #c0392b;
  box-shadow: 0 0 0 3px rgba(192, 57, 43, .1);
}

.form-footer {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 16px;
  margin-top: 4px;
}

.form-note { font-size: 12px; color: var(--muted-2); max-width: 22em; }

.form-status {
  grid-column: 1 / -1;
  min-height: 0;
  font-size: 13.5px;
  color: var(--accent);
}

.form-status:not(:empty) {
  padding: 12px 14px;
  background: var(--accent-soft);
  border-radius: var(--radius-sm);
}

/* -------- 15. 页脚 -------- */
.site-footer {
  padding-top: clamp(48px, 6vw, 72px);
  background: var(--surface);
  border-top: 1px solid var(--line);
}

.footer-grid {
  display: grid;
  grid-template-columns: 1.6fr 1fr 1fr 1.2fr;
  gap: 40px;
  padding-bottom: 48px;
}

.footer-brand p {
  margin-top: 16px;
  font-size: 13.5px;
  line-height: 1.9;
  color: var(--muted);
}

.site-footer h3 {
  margin-bottom: 16px;
  font-size: 13px;
  font-weight: 600;
  letter-spacing: .06em;
  text-transform: uppercase;
  color: var(--muted-2);
}

.site-footer ul { display: grid; gap: 10px; font-size: 14px; color: var(--muted); }
.site-footer ul a { transition: color .2s var(--ease); }
.site-footer ul a:hover { color: var(--accent); }

.footer-bottom {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: 12px;
  padding-block: 22px;
  border-top: 1px solid var(--line);
  font-size: 12.5px;
  color: var(--muted-2);
}

.footer-bottom a:hover { color: var(--accent); }

/* -------- 16. 动效 -------- */
.anim .reveal {
  opacity: 0;
  transform: translateY(18px);
  transition: opacity .7s var(--ease), transform .7s var(--ease);
}

.anim .reveal.is-visible {
  opacity: 1;
  transform: none;
}

/* 同组元素依次出现 */
.grid .reveal:nth-child(2) { transition-delay: .07s; }
.grid .reveal:nth-child(3) { transition-delay: .14s; }
.grid .reveal:nth-child(4) { transition-delay: .21s; }
.steps .reveal:nth-child(2) { transition-delay: .07s; }
.steps .reveal:nth-child(3) { transition-delay: .14s; }
.steps .reveal:nth-child(4) { transition-delay: .21s; }

/* -------- 响应式 -------- */
@media (max-width: 1080px) {
  .footer-grid { grid-template-columns: 1fr 1fr; gap: 36px 24px; }
}

@media (max-width: 960px) {
  .hero-inner { grid-template-columns: 1fr; gap: 48px; }
  .hero-media { max-width: 620px; width: 100%; margin-inline: auto; }
  .about-grid { grid-template-columns: 1fr; gap: 44px; }
  .about-media { max-width: 520px; }
}

@media (max-width: 900px) {
  :root { --header-h: 64px; }

  .nav {
    position: fixed;
    inset: var(--header-h) 0 auto;
    flex-direction: column;
    align-items: stretch;
    gap: 2px;
    padding: 16px var(--gutter) 24px;
    background: var(--bg);
    border-bottom: 1px solid var(--line);
    box-shadow: 0 24px 40px -24px rgba(13, 17, 23, .25);
    transform: translateY(-8px);
    opacity: 0;
    visibility: hidden;
    transition: opacity .25s var(--ease), transform .25s var(--ease), visibility .25s;
  }

  .nav.is-open { opacity: 1; visibility: visible; transform: none; }

  .nav > a { padding: 12px 8px; font-size: 16px; border-radius: 8px; }
  .nav > a.is-active::after { display: none; }
  .nav-cta { margin: 12px 0 0; padding: 12px; text-align: center; }
  .nav-toggle { display: block; }

  .grid-2, .grid-3 { grid-template-columns: 1fr; }
  .steps { grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 28px 20px; }
  .section-head--row { flex-direction: column; align-items: flex-start; gap: 18px; }
  .section-desc--side { max-width: 100%; }
  .contact-grid { grid-template-columns: 1fr; }
  .cta-inner { flex-direction: column; align-items: flex-start; }
  .faq-grid { grid-template-columns: 1fr; gap: 32px; }
  .faq-head { position: static; }
  .industry-label { display: none; }
  .industry-inner { gap: 10px 20px; }
}

@media (max-width: 620px) {
  :root { --gutter: 20px; }

  .hero { padding-top: 40px; }
  .hero-title { font-size: clamp(30px, 8.6vw, 40px); }
  .hero-actions .btn { flex: 1 1 100%; }
  .hero-media { transform: none; }
  .hero-media figcaption { left: 8px; right: 8px; bottom: 8px; font-size: 11.5px; }
  .hero-tags { gap: 6px; margin-top: 22px; }
  .hero-tags li { font-size: 12px; padding: 4px 10px; }

  .industry-list { gap: 8px 18px; font-size: 13.5px; }

  .card, .contact-form { padding: 24px; }
  .case-cover { height: 176px; }

  .stats--row { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .stat { padding: 24px 20px; }
  .stat-num { font-size: 32px; }

  .contact-form { grid-template-columns: 1fr; }
  .form-footer { flex-direction: column; align-items: stretch; }
  .form-footer .btn { width: 100%; }

  .footer-grid { grid-template-columns: 1fr 1fr; }
  .footer-brand { grid-column: 1 / -1; }
  .footer-bottom { flex-direction: column; }
}

/* 减少动态效果偏好 */
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after {
    animation-duration: .001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: .001ms !important;
  }
  .anim .reveal { opacity: 1; transform: none; }
}

/* 打印 */
@media print {
  .site-header, .nav-toggle, .hero-bg, .cta-band { display: none !important; }
  body { background: #fff; }
  .section { padding: 24px 0; }
}