/* ============================================
   常羲网络 · 公司官网样式
   ============================================ */

/* ---------- 设计变量 ---------- */
:root {
  /* 主题色 */
  --primary: #6366f1;
  --primary-600: #4f46e5;
  --primary-700: #4338ca;
  --cyan: #06b6d4;
  --violet: #8b5cf6;

  /* 文字 */
  --text: #0f172a;
  --text-soft: #475569;
  --text-mute: #64748b;
  --text-light: #94a3b8;
  --text-inverse: #f8fafc;

  /* 背景 */
  --bg: #ffffff;
  --bg-alt: #f8fafc;
  --bg-dark: #0b1020;
  --bg-dark-2: #0f172a;
  --card: #ffffff;

  /* 边框 */
  --border: #e2e8f0;
  --border-soft: #eef2f7;

  /* 阴影 */
  --shadow-sm: 0 1px 2px rgba(15, 23, 42, 0.04), 0 1px 3px rgba(15, 23, 42, 0.06);
  --shadow: 0 4px 16px rgba(15, 23, 42, 0.06), 0 1px 3px rgba(15, 23, 42, 0.04);
  --shadow-lg: 0 20px 40px -12px rgba(15, 23, 42, 0.12), 0 8px 16px -8px rgba(15, 23, 42, 0.08);
  --shadow-glow: 0 10px 40px -10px rgba(99, 102, 241, 0.45);

  /* 圆角 */
  --r-sm: 8px;
  --r: 12px;
  --r-lg: 16px;
  --r-xl: 24px;
  --r-full: 999px;

  /* 渐变 */
  --grad: linear-gradient(135deg, #6366f1 0%, #06b6d4 100%);
  --grad-2: linear-gradient(135deg, #8b5cf6 0%, #ec4899 100%);

  /* 容器 */
  --container: 1200px;
}

/* ---------- 重置 ---------- */
*, *::before, *::after { box-sizing: border-box; }
html { scroll-behavior: smooth; -webkit-text-size-adjust: 100%; }
body {
  margin: 0;
  font-family: "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Helvetica Neue", Helvetica, Arial, "Segoe UI", system-ui, -apple-system, sans-serif;
  font-size: 16px;
  line-height: 1.7;
  color: var(--text);
  background: var(--bg);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}
img, svg { display: block; max-width: 100%; }
a { color: inherit; text-decoration: none; }
button { font-family: inherit; cursor: pointer; border: none; background: none; }
input, textarea, select { font-family: inherit; font-size: inherit; }
ul { margin: 0; padding: 0; list-style: none; }

/* ---------- 容器 ---------- */
.container {
  width: 100%;
  max-width: var(--container);
  margin: 0 auto;
  padding: 0 24px;
}

/* ---------- 渐变文字 ---------- */
.gradient-text {
  background: var(--grad);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
  color: transparent;
}

/* ---------- 按钮 ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 14px 28px;
  border-radius: var(--r-full);
  font-size: 15px;
  font-weight: 600;
  letter-spacing: 0.01em;
  transition: transform 0.2s ease, box-shadow 0.2s ease, background 0.2s ease, color 0.2s ease;
  white-space: nowrap;
}
.btn--primary {
  background: var(--grad);
  color: #fff;
  box-shadow: var(--shadow-glow);
}
.btn--primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 16px 50px -10px rgba(99, 102, 241, 0.6);
}
.btn--ghost {
  background: rgba(255, 255, 255, 0.7);
  color: var(--text);
  border: 1px solid var(--border);
  backdrop-filter: blur(8px);
}
.btn--ghost:hover {
  border-color: var(--primary);
  color: var(--primary);
  transform: translateY(-2px);
}
.btn--sm { padding: 9px 20px; font-size: 14px; }
.btn--block { width: 100%; }

/* ---------- 顶部公告条 ---------- */
.top-bar {
  background: var(--bg-dark);
  color: #cbd5e1;
  font-size: 13px;
  padding: 8px 0;
}
.top-bar__inner {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 16px;
  flex-wrap: wrap;
}
.top-bar__text { display: inline-flex; align-items: center; gap: 8px; }
.top-bar .dot {
  width: 8px; height: 8px;
  border-radius: 50%;
  background: #34d399;
  box-shadow: 0 0 0 4px rgba(52, 211, 153, 0.2);
  animation: pulse 2s infinite;
}
.top-bar__contact a { color: #93c5fd; }
.top-bar__contact a:hover { color: #fff; }

@keyframes pulse {
  0%, 100% { opacity: 1; }
  50% { opacity: 0.4; }
}

/* ---------- 导航 ---------- */
.nav {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(255, 255, 255, 0.85);
  backdrop-filter: saturate(180%) blur(12px);
  border-bottom: 1px solid transparent;
  transition: box-shadow 0.3s ease, border-color 0.3s ease, background 0.3s ease;
}
.nav.is-scrolled {
  box-shadow: var(--shadow-sm);
  border-bottom-color: var(--border-soft);
}
.nav__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 72px;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 12px;
}
.brand__logo { display: inline-flex; }
.brand__text { display: flex; flex-direction: column; line-height: 1.1; }
.brand__name {
  font-size: 17px;
  font-weight: 700;
  color: var(--text);
  letter-spacing: 0.02em;
}
.brand__sub {
  font-size: 10px;
  letter-spacing: 0.18em;
  color: var(--text-light);
  margin-top: 2px;
}

.nav__menu {
  display: flex;
  align-items: center;
  gap: 32px;
}
.nav__link {
  font-size: 15px;
  font-weight: 500;
  color: var(--text-soft);
  position: relative;
  transition: color 0.2s ease;
  padding: 8px 0;
}
.nav__link::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: 0;
  width: 0;
  height: 2px;
  background: var(--grad);
  border-radius: 2px;
  transition: width 0.25s ease;
}
.nav__link:hover { color: var(--primary); }
.nav__link:hover::after { width: 100%; }

.nav__actions {
  display: flex;
  align-items: center;
  gap: 12px;
}
.nav__toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  padding: 8px;
}
.nav__toggle span {
  width: 24px; height: 2px;
  background: var(--text);
  border-radius: 2px;
  transition: transform 0.3s ease, opacity 0.2s ease;
}
.nav__toggle.is-open span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
.nav__toggle.is-open span:nth-child(2) { opacity: 0; }
.nav__toggle.is-open span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }

/* ---------- Hero ---------- */
.hero {
  position: relative;
  overflow: hidden;
  background:
    radial-gradient(ellipse 80% 60% at 20% 0%, rgba(99, 102, 241, 0.12), transparent 60%),
    radial-gradient(ellipse 70% 60% at 90% 20%, rgba(6, 182, 212, 0.10), transparent 60%),
    linear-gradient(180deg, #fbfcff 0%, #ffffff 100%);
  padding: 80px 0 120px;
}
.hero__bg { position: absolute; inset: 0; z-index: 0; pointer-events: none; }

/* 网格背景 */
.hero__grid {
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(99, 102, 241, 0.06) 1px, transparent 1px),
    linear-gradient(90deg, rgba(99, 102, 241, 0.06) 1px, transparent 1px);
  background-size: 48px 48px;
  mask-image: radial-gradient(ellipse 70% 60% at 50% 30%, #000 30%, transparent 80%);
  -webkit-mask-image: radial-gradient(ellipse 70% 60% at 50% 30%, #000 30%, transparent 80%);
}

/* 光球 */
.hero__orb {
  position: absolute;
  border-radius: 50%;
  filter: blur(60px);
  opacity: 0.55;
  animation: float 12s ease-in-out infinite;
}
.hero__orb--1 {
  width: 380px; height: 380px;
  top: -80px; left: -100px;
  background: radial-gradient(circle, #6366f1, transparent 70%);
}
.hero__orb--2 {
  width: 460px; height: 460px;
  bottom: -120px; right: -120px;
  background: radial-gradient(circle, #06b6d4, transparent 70%);
  animation-delay: -4s;
}
@keyframes float {
  0%, 100% { transform: translate(0, 0); }
  50% { transform: translate(20px, -30px); }
}

.hero__inner {
  position: relative;
  z-index: 1;
  display: grid;
  grid-template-columns: 1.1fr 0.9fr;
  gap: 64px;
  align-items: center;
}

.hero__badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 6px 14px;
  background: rgba(99, 102, 241, 0.08);
  border: 1px solid rgba(99, 102, 241, 0.2);
  border-radius: var(--r-full);
  font-size: 13px;
  font-weight: 500;
  color: var(--primary-700);
}
.badge-dot {
  width: 8px; height: 8px;
  background: var(--primary);
  border-radius: 50%;
  box-shadow: 0 0 0 3px rgba(99, 102, 241, 0.2);
}

.hero__title {
  font-size: clamp(36px, 5.2vw, 60px);
  line-height: 1.15;
  font-weight: 800;
  letter-spacing: -0.02em;
  margin: 20px 0 18px;
  color: var(--text);
}
.hero__desc {
  font-size: 17px;
  color: var(--text-soft);
  max-width: 540px;
  margin: 0 0 32px;
}
.hero__cta {
  display: flex;
  gap: 14px;
  flex-wrap: wrap;
  margin-bottom: 56px;
}

.hero__stats {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
  padding-top: 32px;
  border-top: 1px solid var(--border-soft);
}
.stat__num {
  font-size: 32px;
  font-weight: 800;
  background: var(--grad);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
  line-height: 1;
}
.stat__plus { font-size: 22px; margin-left: 2px; }
.stat__label {
  font-size: 13px;
  color: var(--text-mute);
  margin-top: 8px;
}

/* Hero 视觉区 */
.hero__visual {
  position: relative;
  min-height: 460px;
}
.hero__card { position: absolute; }
.hero__card--main {
  inset: 0;
  z-index: 2;
}
.code-window {
  background: #0b1020;
  border-radius: var(--r-lg);
  box-shadow: var(--shadow-lg);
  overflow: hidden;
  border: 1px solid rgba(255, 255, 255, 0.08);
}
.code-window__bar {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 12px 16px;
  background: #131a30;
  border-bottom: 1px solid rgba(255, 255, 255, 0.06);
}
.cw-dot {
  width: 12px; height: 12px;
  border-radius: 50%;
}
.cw-dot--red { background: #ff5f56; }
.cw-dot--yellow { background: #ffbd2e; }
.cw-dot--green { background: #27c93f; }
.code-window__title {
  margin-left: 8px;
  color: #64748b;
  font-size: 12px;
  font-family: "JetBrains Mono", "Consolas", monospace;
}
.code-window__body {
  margin: 0;
  padding: 24px;
  color: #cbd5e1;
  font-family: "JetBrains Mono", "Consolas", "Courier New", monospace;
  font-size: 14px;
  line-height: 1.9;
  overflow-x: auto;
}
.c-key { color: #c084fc; }
.c-var { color: #60a5fa; }
.c-prop { color: #93c5fd; }
.c-str { color: #6ee7b7; }
.c-num { color: #fbbf24; }

.hero__card--float {
  z-index: 3;
  filter: drop-shadow(0 12px 24px rgba(15, 23, 42, 0.12));
  animation: floatY 6s ease-in-out infinite;
}
.hero__card--a {
  top: -28px;
  right: -16px;
}
.hero__card--b {
  bottom: -28px;
  left: -28px;
  animation-delay: -3s;
}
@keyframes floatY {
  0%, 100% { transform: translateY(0); }
  50% { transform: translateY(-12px); }
}
.mini-card {
  display: flex;
  align-items: center;
  gap: 12px;
  background: #fff;
  border-radius: var(--r);
  padding: 12px 16px;
  border: 1px solid var(--border);
}
.mini-card__icon {
  width: 40px; height: 40px;
  border-radius: var(--r-sm);
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
}
.mini-card__title { font-size: 14px; font-weight: 700; color: var(--text); }
.mini-card__sub { font-size: 12px; color: var(--text-mute); }

/* Hero 底部波浪 */
.hero__wave {
  position: absolute;
  bottom: -1px;
  left: 0;
  right: 0;
  line-height: 0;
}
.hero__wave svg { width: 100%; height: 80px; }

/* ---------- 信任带 ---------- */
.trust {
  padding: 40px 0;
  background: var(--bg);
}
.trust__label {
  text-align: center;
  color: var(--text-mute);
  font-size: 14px;
  margin: 0 0 20px;
}
.trust__row {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 16px 36px;
}
.trust__row span {
  font-size: 16px;
  font-weight: 600;
  color: var(--text-light);
  letter-spacing: 0.04em;
  transition: color 0.2s ease;
}
.trust__row span:hover { color: var(--primary); }

/* ---------- 通用 section ---------- */
.section { padding: 96px 0; }
.section--alt { background: var(--bg-alt); }
.section--dark {
  background:
    radial-gradient(ellipse 60% 50% at 20% 0%, rgba(99, 102, 241, 0.18), transparent 60%),
    radial-gradient(ellipse 60% 50% at 90% 100%, rgba(6, 182, 212, 0.12), transparent 60%),
    var(--bg-dark);
  color: #e2e8f0;
}
.section__head {
  text-align: center;
  max-width: 720px;
  margin: 0 auto 56px;
}
.section__eyebrow {
  display: inline-block;
  font-size: 13px;
  font-weight: 600;
  letter-spacing: 0.18em;
  color: var(--primary);
  text-transform: uppercase;
  margin-bottom: 14px;
  padding: 4px 12px;
  background: rgba(99, 102, 241, 0.08);
  border-radius: var(--r-full);
}
.section__eyebrow--light {
  color: #a5b4fc;
  background: rgba(165, 180, 252, 0.1);
}
.section__title {
  font-size: clamp(28px, 3.6vw, 42px);
  font-weight: 800;
  letter-spacing: -0.02em;
  margin: 0 0 16px;
  line-height: 1.25;
}
.section__title--light { color: #fff; }
.section__desc {
  font-size: 17px;
  color: var(--text-soft);
  margin: 0;
}
.section__desc--light { color: #94a3b8; }

/* ---------- 服务卡片 ---------- */
.services-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}
.service-card {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: var(--r-lg);
  padding: 32px;
  transition: transform 0.3s ease, box-shadow 0.3s ease, border-color 0.3s ease;
  position: relative;
  overflow: hidden;
}
.service-card::before {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(135deg, rgba(99, 102, 241, 0.04), rgba(6, 182, 212, 0.04));
  opacity: 0;
  transition: opacity 0.3s ease;
}
.service-card:hover {
  transform: translateY(-6px);
  box-shadow: var(--shadow-lg);
  border-color: transparent;
}
.service-card:hover::before { opacity: 1; }
.service-card > * { position: relative; z-index: 1; }

.service-card__icon {
  width: 56px; height: 56px;
  border-radius: var(--r);
  background: linear-gradient(135deg, var(--ic-1), var(--ic-2));
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: 0 8px 20px -6px var(--ic-1);
  margin-bottom: 20px;
}
.service-card__title {
  font-size: 20px;
  font-weight: 700;
  margin: 0 0 10px;
  color: var(--text);
}
.service-card__desc {
  font-size: 14.5px;
  color: var(--text-soft);
  margin: 0 0 18px;
  line-height: 1.7;
}
.service-card__list { display: flex; flex-direction: column; gap: 8px; }
.service-card__list li {
  font-size: 14px;
  color: var(--text-soft);
  padding-left: 24px;
  position: relative;
}
.service-card__list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 8px;
  width: 14px; height: 14px;
  background: var(--grad);
  border-radius: 50%;
  opacity: 0.15;
}
.service-card__list li::after {
  content: "";
  position: absolute;
  left: 5px;
  top: 11px;
  width: 4px; height: 7px;
  border-right: 2px solid var(--primary);
  border-bottom: 2px solid var(--primary);
  transform: rotate(45deg);
}

/* ---------- 解决方案 ---------- */
.solutions {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
}
.solution {
  display: flex;
  gap: 20px;
  padding: 28px;
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: var(--r-lg);
  transition: transform 0.3s ease, box-shadow 0.3s ease, border-color 0.3s ease;
}
.solution:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow);
  border-color: rgba(99, 102, 241, 0.4);
}
.solution__num {
  font-size: 36px;
  font-weight: 800;
  background: var(--grad);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
  line-height: 1;
  flex-shrink: 0;
}
.solution__body h3 {
  font-size: 18px;
  font-weight: 700;
  margin: 0 0 8px;
  color: var(--text);
}
.solution__body p {
  font-size: 14px;
  color: var(--text-soft);
  margin: 0;
  line-height: 1.7;
}

/* ---------- 优势 ---------- */
.advantages {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}
.advantage {
  padding: 32px;
  border-radius: var(--r-lg);
  background: var(--card);
  border: 1px solid var(--border);
  transition: transform 0.3s ease, box-shadow 0.3s ease;
}
.advantage:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
}
.advantage__icon {
  width: 48px; height: 48px;
  border-radius: var(--r);
  background: linear-gradient(135deg, rgba(99, 102, 241, 0.1), rgba(6, 182, 212, 0.1));
  color: var(--primary);
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 18px;
}
.advantage h3 {
  font-size: 18px;
  font-weight: 700;
  margin: 0 0 10px;
  color: var(--text);
}
.advantage p {
  font-size: 14.5px;
  color: var(--text-soft);
  margin: 0;
  line-height: 1.7;
}

/* ---------- 流程 ---------- */
.process {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
}
.process__step {
  position: relative;
  padding: 32px;
  background: rgba(255, 255, 255, 0.04);
  border: 1px solid rgba(255, 255, 255, 0.08);
  border-radius: var(--r-lg);
  transition: transform 0.3s ease, background 0.3s ease, border-color 0.3s ease;
}
.process__step:hover {
  transform: translateY(-4px);
  background: rgba(255, 255, 255, 0.06);
  border-color: rgba(99, 102, 241, 0.4);
}
.process__num {
  width: 44px; height: 44px;
  border-radius: 50%;
  background: var(--grad);
  color: #fff;
  font-weight: 800;
  font-size: 18px;
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 18px;
  box-shadow: 0 8px 20px -6px rgba(99, 102, 241, 0.6);
}
.process__step h3 {
  font-size: 18px;
  font-weight: 700;
  margin: 0 0 8px;
  color: #fff;
}
.process__step p {
  font-size: 14px;
  color: #94a3b8;
  margin: 0;
  line-height: 1.7;
}

/* ---------- 联系 ---------- */
.contact-cta {
  max-width: 720px;
  margin: 0 auto;
  text-align: center;
}
.contact-cta .section__title { margin-bottom: 16px; }
.contact-cta__desc {
  font-size: 17px;
  color: var(--text-soft);
  margin: 0 0 32px;
}
.contact-cta__btn {
  font-size: 16px;
  padding: 16px 32px;
}
.contact-cta__items {
  display: flex;
  justify-content: center;
  flex-wrap: wrap;
  gap: 20px;
  margin-top: 40px;
}
.contact-cta__items .contact__item { min-width: 220px; text-align: left; }
.contact__item {
  display: flex;
  align-items: center;
  gap: 14px;
  padding: 16px 20px;
  background: var(--bg-alt);
  border: 1px solid var(--border-soft);
  border-radius: var(--r);
  transition: transform 0.2s ease, border-color 0.2s ease;
}
.contact__item:hover {
  transform: translateY(-2px);
  border-color: var(--primary);
}
.contact__icon {
  width: 44px; height: 44px;
  border-radius: var(--r-sm);
  background: linear-gradient(135deg, rgba(99, 102, 241, 0.1), rgba(6, 182, 212, 0.1));
  color: var(--primary);
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
}
.contact__label {
  font-size: 12px;
  color: var(--text-mute);
  margin-bottom: 2px;
}
.contact__value {
  font-size: 15px;
  font-weight: 600;
  color: var(--text);
}

/* ---------- Footer ---------- */
.footer {
  background: var(--bg-dark-2);
  color: #cbd5e1;
  padding-top: 64px;
}
.footer__inner {
  display: grid;
  grid-template-columns: 1.6fr 1fr 1fr 1fr;
  gap: 40px;
  padding-bottom: 48px;
}
.footer__brand .brand__name { color: #fff; }
.footer__brand .brand__sub { color: #64748b; }
.footer__tagline {
  margin: 20px 0 0;
  font-size: 14px;
  color: #94a3b8;
  line-height: 1.7;
}
.footer__col h4 {
  font-size: 14px;
  font-weight: 700;
  color: #fff;
  margin: 0 0 16px;
  letter-spacing: 0.04em;
}
.footer__col a,
.footer__col span {
  display: block;
  font-size: 14px;
  color: #94a3b8;
  margin-bottom: 10px;
  transition: color 0.2s ease;
}
.footer__col a:hover { color: #fff; }
.footer__bottom {
  border-top: 1px solid rgba(255, 255, 255, 0.08);
  padding: 20px 0;
}
.footer__bottom-inner {
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 12px;
  font-size: 13px;
  color: #64748b;
}
.footer__icp { color: #475569; }
.footer__icp a { color: inherit; text-decoration: none; transition: color 0.2s ease; }
.footer__icp a:hover { color: #94a3b8; }

/* ---------- 回到顶部 ---------- */
.to-top {
  position: fixed;
  right: 28px;
  bottom: 28px;
  width: 48px;
  height: 48px;
  border-radius: 50%;
  background: var(--grad);
  color: #fff;
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: var(--shadow-glow);
  opacity: 0;
  visibility: hidden;
  transform: translateY(20px);
  transition: opacity 0.3s ease, transform 0.3s ease, visibility 0.3s ease;
  z-index: 50;
}
.to-top.is-visible {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}
.to-top:hover { transform: translateY(-4px); }

/* ---------- 滚动揭示动画 ---------- */
.reveal {
  opacity: 0;
  transform: translateY(24px);
  transition: opacity 0.7s cubic-bezier(0.16, 1, 0.3, 1), transform 0.7s cubic-bezier(0.16, 1, 0.3, 1);
  transition-delay: 0ms;
}
.reveal.is-visible {
  opacity: 1;
  transform: translateY(0);
}

/* ---------- 响应式 ---------- */
@media (max-width: 980px) {
  .hero__inner { grid-template-columns: 1fr; gap: 40px; }
  .hero__visual { min-height: 360px; max-width: 480px; }
  .footer__inner { grid-template-columns: 1fr 1fr; gap: 32px; }
}

@media (max-width: 820px) {
  .nav__menu {
    position: fixed;
    top: 72px;
    left: 0;
    right: 0;
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    background: #fff;
    padding: 8px 24px 24px;
    border-bottom: 1px solid var(--border);
    box-shadow: var(--shadow-lg);
    transform: translateY(-120%);
    opacity: 0;
    visibility: hidden;
    transition: transform 0.3s ease, opacity 0.3s ease, visibility 0.3s ease;
  }
  .nav__menu.is-open {
    transform: translateY(0);
    opacity: 1;
    visibility: visible;
  }
  .nav__link {
    padding: 14px 0;
    border-bottom: 1px solid var(--border-soft);
    font-size: 16px;
  }
  .nav__link:last-child { border-bottom: none; }
  .nav__toggle { display: flex; }
  .nav__actions .btn--sm { display: none; }

  .services-grid,
  .solutions,
  .advantages,
  .process { grid-template-columns: repeat(2, 1fr); }

  .hero__stats { grid-template-columns: repeat(2, 1fr); gap: 20px; }
  .section { padding: 72px 0; }
}

@media (max-width: 560px) {
  .container { padding: 0 18px; }
  .hero { padding: 48px 0 80px; }
  .hero__stats { grid-template-columns: repeat(2, 1fr); }
  .stat__num { font-size: 26px; }

  .services-grid,
  .solutions,
  .advantages,
  .process,
  .footer__inner { grid-template-columns: 1fr; }

  .service-card,
  .solution,
  .advantage,
  .process__step { padding: 24px; }

  .contact-form { padding: 28px 22px; }

  .hero__cta { width: 100%; }
  .hero__cta .btn { flex: 1; }

  .hero__card--a { right: 0; }
  .hero__card--b { left: 0; }

  .section__head { margin-bottom: 40px; }
  .footer__bottom-inner { justify-content: center; text-align: center; }
}

/* ---------- 无障碍 ---------- */
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
    scroll-behavior: auto !important;
  }
  .reveal { opacity: 1; transform: none; }
}

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