/* ============================================================
   龙腾科创官网 · 深色科技感设计系统 v3.0
   纯手写 CSS，无框架依赖
   ============================================================ */

/* ---------- 1. 设计 Token ---------- */
:root {
  /* 表面色（深空蓝黑三层） */
  --bg: #060a14;
  --surface: #0b1220;
  --surface-2: #111a2e;
  --surface-3: #16223c;

  /* 品牌色 */
  --accent: #4c9aff;
  --accent-cyan: #00d4ff;
  --accent-deep: #1e5fd6;
  --gradient: linear-gradient(135deg, #4c9aff 0%, #00d4ff 100%);
  --accent-soft: rgba(76, 154, 255, 0.12);

  /* 文字 */
  --text: #e6edf7;
  --text-secondary: #9aa8c0;
  --text-muted: #5f6b82;

  /* 描边与分隔 */
  --border: rgba(255, 255, 255, 0.08);
  --border-strong: rgba(255, 255, 255, 0.14);

  /* 功能色（深底适配） */
  --success: #34d399;
  --warning: #fbbf24;
  --danger: #f87171;

  /* 阴影（深色环境：低透明大模糊 + 品牌色 glow） */
  --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.35);
  --shadow-md: 0 8px 24px rgba(0, 0, 0, 0.45);
  --shadow-lg: 0 16px 48px rgba(0, 0, 0, 0.55);
  --shadow-glow: 0 0 24px rgba(76, 154, 255, 0.25);
  --shadow-glow-lg: 0 0 48px rgba(76, 154, 255, 0.35);

  /* 圆角 */
  --radius-sm: 8px;
  --radius-md: 12px;
  --radius-lg: 16px;
  --radius-xl: 24px;

  /* 布局 */
  --header-height: 72px;
  --section-spacing: clamp(80px, 10vw, 128px);
  --container-width: 1200px;

  /* 动效 */
  --transition: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  --transition-slow: 0.6s cubic-bezier(0.4, 0, 0.2, 1);

  /* 字体 */
  --font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC",
    "Hiragino Sans GB", "Noto Sans SC", "Microsoft YaHei", sans-serif;
}

/* ---------- 2. 基础重置 ---------- */
*,
*::before,
*::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  scroll-behavior: smooth;
  scroll-padding-top: var(--header-height);
}

body {
  font-family: var(--font-family);
  background-color: var(--bg);
  color: var(--text);
  line-height: 1.7;
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}

img {
  max-width: 100%;
  height: auto;
  display: block;
}

a {
  color: var(--accent);
  text-decoration: none;
  transition: color var(--transition);
}

a:hover {
  color: var(--accent-cyan);
}

ul {
  list-style: none;
}

button {
  font-family: inherit;
  cursor: pointer;
}

/* 可访问性：焦点环 */
:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 3px;
  border-radius: 4px;
}

/* 跳转链接（视觉隐藏，聚焦可见） */
.skip-link {
  position: absolute;
  top: -100px;
  left: 16px;
  z-index: 200;
  padding: 10px 20px;
  background: var(--accent);
  color: #fff;
  border-radius: var(--radius-sm);
  transition: top var(--transition);
}

.skip-link:focus {
  top: 12px;
  color: #fff;
}

::selection {
  background: rgba(76, 154, 255, 0.35);
  color: #fff;
}

/* ---------- 3. 排版 ---------- */
h1,
h2,
h3,
h4,
h5,
h6 {
  line-height: 1.25;
  font-weight: 700;
  color: var(--text);
}

h1 {
  font-size: clamp(2.5rem, 6vw, 4.5rem);
  font-weight: 800;
  letter-spacing: -0.02em;
}

h2 {
  font-size: clamp(1.75rem, 4vw, 2.5rem);
  letter-spacing: -0.01em;
}

h3 {
  font-size: clamp(1.2rem, 2.5vw, 1.5rem);
}

h4 {
  font-size: 1.05rem;
}

p {
  color: var(--text-secondary);
}

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

/* ---------- 4. 布局 ---------- */
.container {
  max-width: var(--container-width);
  margin: 0 auto;
  padding: 0 24px;
  position: relative;
  z-index: 1;
}

.section {
  padding: var(--section-spacing) 0;
  position: relative;
}

.section-alt {
  background: var(--surface);
}

/* 区块标题组件 */
.section-header {
  max-width: 720px;
  margin: 0 auto 56px;
  text-align: center;
}

.section-header.align-left {
  margin-left: 0;
  text-align: left;
}

.eyebrow {
  display: inline-block;
  padding: 6px 16px;
  margin-bottom: 16px;
  font-size: 0.8rem;
  font-weight: 600;
  letter-spacing: 0.08em;
  color: var(--accent);
  background: var(--accent-soft);
  border: 1px solid rgba(76, 154, 255, 0.25);
  border-radius: 999px;
}

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

.section-header p {
  font-size: 1.05rem;
}

/* 通用网格 */
.grid-2,
.grid-3,
.grid-4 {
  display: grid;
  gap: 24px;
}

.grid-2 { grid-template-columns: repeat(2, 1fr); }
.grid-3 { grid-template-columns: repeat(3, 1fr); }
.grid-4 { grid-template-columns: repeat(4, 1fr); }

/* Bento 网格（核心业务） */
.bento-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 24px;
}

/* 背景装饰工具类 */
.bg-grid {
  background-image:
    linear-gradient(rgba(76, 154, 255, 0.05) 1px, transparent 1px),
    linear-gradient(90deg, rgba(76, 154, 255, 0.05) 1px, transparent 1px);
  background-size: 48px 48px;
}

.glow-orb {
  position: absolute;
  border-radius: 50%;
  filter: blur(100px);
  pointer-events: none;
  z-index: 0;
}

.glow-orb.blue {
  background: rgba(30, 95, 214, 0.35);
}

.glow-orb.cyan {
  background: rgba(0, 212, 255, 0.18);
}

/* ---------- 5. 按钮 ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 14px 32px;
  font-size: 1rem;
  font-weight: 600;
  line-height: 1;
  border: 1px solid transparent;
  border-radius: var(--radius-md);
  transition: all var(--transition);
  white-space: nowrap;
}

.btn:active {
  transform: scale(0.98);
}

.btn-primary {
  background: var(--gradient);
  color: #04101f;
  box-shadow: var(--shadow-glow);
}

.btn-primary:hover {
  color: #04101f;
  transform: translateY(-2px);
  box-shadow: var(--shadow-glow-lg);
}

.btn-outline {
  background: transparent;
  color: var(--text);
  border-color: var(--border-strong);
}

.btn-outline:hover {
  color: var(--accent-cyan);
  border-color: var(--accent);
  background: var(--accent-soft);
  transform: translateY(-2px);
}

.btn-ghost {
  background: transparent;
  color: var(--accent);
  padding: 10px 16px;
}

.btn-ghost:hover {
  background: var(--accent-soft);
}

.btn-white {
  background: rgba(255, 255, 255, 0.08);
  color: var(--text);
  border-color: var(--border);
  backdrop-filter: blur(8px);
}

.btn-white:hover {
  color: var(--accent-cyan);
  border-color: var(--accent);
  transform: translateY(-2px);
}

.btn-sm {
  padding: 10px 20px;
  font-size: 0.9rem;
}

/* ---------- 6. 导航栏 ---------- */
.navbar {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  height: var(--header-height);
  background: rgba(6, 10, 20, 0.72);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border-bottom: 1px solid transparent;
  transition: all var(--transition);
}

.navbar.scrolled {
  background: rgba(6, 10, 20, 0.92);
  border-bottom-color: var(--border);
  box-shadow: var(--shadow-md);
}

.navbar-container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: var(--header-height);
}

.logo {
  display: flex;
  align-items: center;
  gap: 10px;
}

.logo img {
  height: 40px;
  width: auto;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 8px;
}

.nav-links a {
  position: relative;
  display: block;
  padding: 10px 16px;
  font-size: 0.95rem;
  font-weight: 500;
  color: var(--text-secondary);
}

.nav-links a::after {
  content: "";
  position: absolute;
  left: 16px;
  right: 16px;
  bottom: 4px;
  height: 2px;
  background: var(--gradient);
  border-radius: 2px;
  transform: scaleX(0);
  transform-origin: left;
  transition: transform var(--transition);
}

.nav-links a:hover,
.nav-links a.active {
  color: var(--text);
}

.nav-links a:hover::after,
.nav-links a.active::after {
  transform: scaleX(1);
}

.nav-cta {
  margin-left: 12px;
}

/* 汉堡按钮（<button>，三线 → X） */
.nav-toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  width: 44px;
  height: 44px;
  padding: 10px;
  background: transparent;
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
}

.nav-toggle span {
  display: block;
  width: 100%;
  height: 2px;
  background: var(--text);
  border-radius: 2px;
  transition: all var(--transition);
}

.nav-toggle.active span:nth-child(1) {
  transform: translateY(7px) rotate(45deg);
}

.nav-toggle.active span:nth-child(2) {
  opacity: 0;
}

.nav-toggle.active span:nth-child(3) {
  transform: translateY(-7px) rotate(-45deg);
}

/* ---------- 7. Hero ---------- */
.hero {
  position: relative;
  min-height: 100vh;
  min-height: 100svh;
  display: flex;
  align-items: center;
  padding: calc(var(--header-height) + 48px) 0 96px;
  overflow: hidden;
}

.hero-bg {
  position: absolute;
  inset: 0;
  z-index: 0;
}

.hero-bg img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.hero-overlay {
  position: absolute;
  inset: 0;
  z-index: 0;
  background:
    linear-gradient(180deg, rgba(6, 10, 20, 0.55) 0%, rgba(6, 10, 20, 0.75) 60%, var(--bg) 100%);
}

.hero-content {
  max-width: 780px;
}

.hero-eyebrow {
  margin-bottom: 24px;
}

.hero h1 {
  margin-bottom: 24px;
}

.hero-subtitle {
  max-width: 620px;
  margin-bottom: 40px;
  font-size: clamp(1rem, 2vw, 1.2rem);
  color: var(--text-secondary);
}

.hero-buttons {
  display: flex;
  flex-wrap: wrap;
  gap: 16px;
}

/* ---------- 8. 数据条 ---------- */
.stats-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
}

.stat-item {
  text-align: center;
  padding: 32px 16px;
  background: rgba(255, 255, 255, 0.03);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  transition: all var(--transition);
}

.stat-item:hover {
  border-color: rgba(76, 154, 255, 0.4);
  box-shadow: var(--shadow-glow);
  transform: translateY(-4px);
}

.stat-number {
  display: block;
  font-size: clamp(2rem, 4vw, 3rem);
  font-weight: 800;
  line-height: 1.1;
  background: var(--gradient);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
}

.stat-item p {
  margin-top: 8px;
  font-size: 0.95rem;
}

/* ---------- 9. 卡片 ---------- */
.card {
  position: relative;
  padding: 36px 32px;
  background: rgba(255, 255, 255, 0.03);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  transition: all var(--transition);
  overflow: hidden;
}

.card::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 2px;
  background: var(--gradient);
  opacity: 0;
  transition: opacity var(--transition);
}

.card:hover {
  transform: translateY(-6px);
  border-color: rgba(76, 154, 255, 0.35);
  box-shadow: var(--shadow-lg), var(--shadow-glow);
}

.card:hover::before {
  opacity: 1;
}

.card h3 {
  margin-bottom: 12px;
}

.card-icon {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 56px;
  height: 56px;
  margin-bottom: 24px;
  color: var(--accent);
  background: var(--accent-soft);
  border: 1px solid rgba(76, 154, 255, 0.25);
  border-radius: var(--radius-md);
}

.card-icon svg {
  width: 28px;
  height: 28px;
}

.card-image {
  width: 100%;
  aspect-ratio: 3 / 2;
  object-fit: cover;
  border-radius: var(--radius-md);
  margin-bottom: 24px;
  border: 1px solid var(--border);
}

.card .btn {
  margin-top: 24px;
}

/* 标签 */
.tag-list {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-top: 20px;
}

.tag {
  padding: 5px 12px;
  font-size: 0.8rem;
  color: var(--text-secondary);
  background: rgba(255, 255, 255, 0.05);
  border: 1px solid var(--border);
  border-radius: 999px;
}

/* ---------- 10. 图文展示（产品/关于） ---------- */
.showcase {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: clamp(40px, 6vw, 80px);
  align-items: center;
}

.showcase + .showcase {
  margin-top: var(--section-spacing);
}

.showcase.reverse .showcase-media {
  order: 2;
}

.showcase-media {
  position: relative;
}

.showcase-media img {
  width: 100%;
  border-radius: var(--radius-lg);
  border: 1px solid var(--border);
  box-shadow: var(--shadow-lg);
}

.showcase-content h3 {
  margin-bottom: 16px;
  font-size: clamp(1.4rem, 3vw, 1.9rem);
}

.showcase-content > p {
  margin-bottom: 28px;
  font-size: 1.05rem;
}

/* 特性清单 */
.feature-list {
  display: grid;
  gap: 20px;
}

.feature-item {
  display: flex;
  gap: 16px;
  align-items: flex-start;
}

.feature-icon {
  flex-shrink: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  width: 40px;
  height: 40px;
  color: var(--accent-cyan);
  background: var(--accent-soft);
  border-radius: var(--radius-sm);
}

.feature-icon svg {
  width: 20px;
  height: 20px;
}

.feature-item h4 {
  margin-bottom: 4px;
}

.feature-item p {
  font-size: 0.92rem;
}

/* ---------- 11. 服务流程 ---------- */
.process-steps {
  display: grid;
  grid-template-columns: repeat(5, 1fr);
  gap: 24px;
  counter-reset: step;
}

.process-step {
  position: relative;
  padding: 32px 20px 28px;
  background: rgba(255, 255, 255, 0.03);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  text-align: center;
  transition: all var(--transition);
}

.process-step:hover {
  transform: translateY(-4px);
  border-color: rgba(76, 154, 255, 0.35);
}

.step-number {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 48px;
  height: 48px;
  margin-bottom: 16px;
  font-size: 1.15rem;
  font-weight: 800;
  color: #04101f;
  background: var(--gradient);
  border-radius: 50%;
  box-shadow: var(--shadow-glow);
}

.process-step h4 {
  margin-bottom: 8px;
}

.process-step p {
  font-size: 0.88rem;
}

/* ---------- 12. 客户 Logo 墙 ---------- */
.clients-grid {
  display: grid;
  grid-template-columns: repeat(5, 1fr);
  gap: 24px;
}

.client-item {
  display: flex;
  align-items: center;
  justify-content: center;
  min-height: 110px;
  padding: 24px;
  background: rgba(255, 255, 255, 0.04);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  transition: all var(--transition);
}

.client-item img {
  max-height: 56px;
  width: auto;
  filter: grayscale(1) brightness(1.6);
  opacity: 0.75;
  transition: all var(--transition);
}

.client-item:hover {
  border-color: rgba(76, 154, 255, 0.35);
  box-shadow: var(--shadow-glow);
}

.client-item:hover img {
  filter: none;
  opacity: 1;
}

/* ---------- 13. 时间线 ---------- */
.timeline {
  position: relative;
  max-width: 860px;
  margin: 0 auto;
  padding: 24px 0;
}

.timeline::before {
  content: "";
  position: absolute;
  top: 0;
  bottom: 0;
  left: 50%;
  width: 2px;
  background: linear-gradient(180deg, transparent, rgba(76, 154, 255, 0.5) 10%, rgba(76, 154, 255, 0.5) 90%, transparent);
  transform: translateX(-50%);
}

.timeline-item {
  position: relative;
  width: 50%;
  padding: 0 48px 56px 0;
}

.timeline-item:nth-child(even) {
  left: 50%;
  padding: 0 0 56px 48px;
}

.timeline-item::after {
  content: "";
  position: absolute;
  top: 8px;
  right: -8px;
  width: 16px;
  height: 16px;
  background: var(--bg);
  border: 3px solid var(--accent);
  border-radius: 50%;
  box-shadow: var(--shadow-glow);
}

.timeline-item:nth-child(even)::after {
  right: auto;
  left: -8px;
}

.timeline-year {
  display: inline-block;
  margin-bottom: 8px;
  font-size: 1.3rem;
  font-weight: 800;
  background: var(--gradient);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
}

.timeline-content {
  padding: 24px 28px;
  background: rgba(255, 255, 255, 0.03);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  transition: all var(--transition);
}

.timeline-content:hover {
  border-color: rgba(76, 154, 255, 0.35);
  box-shadow: var(--shadow-glow);
}

.timeline-content h3 {
  margin-bottom: 8px;
  font-size: 1.1rem;
}

.timeline-content p {
  font-size: 0.92rem;
}

/* ---------- 14. 团队 ---------- */
.team-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.team-card {
  padding: 32px;
  text-align: center;
  background: rgba(255, 255, 255, 0.03);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  transition: all var(--transition);
}

.team-card:hover {
  transform: translateY(-6px);
  border-color: rgba(76, 154, 255, 0.35);
  box-shadow: var(--shadow-glow);
}

.team-avatar {
  width: 120px;
  height: 120px;
  margin: 0 auto 20px;
  border-radius: 50%;
  object-fit: cover;
  border: 3px solid rgba(76, 154, 255, 0.4);
  box-shadow: var(--shadow-glow);
}

.team-role {
  display: inline-block;
  margin-bottom: 12px;
  padding: 4px 14px;
  font-size: 0.78rem;
  font-weight: 600;
  letter-spacing: 0.05em;
  color: var(--accent-cyan);
  background: var(--accent-soft);
  border-radius: 999px;
}

.team-card h3 {
  margin-bottom: 4px;
}

.team-card p {
  font-size: 0.9rem;
  margin-top: 12px;
}

/* ---------- 15. FAQ ---------- */
.faq-list {
  max-width: 800px;
  margin: 0 auto;
  display: grid;
  gap: 16px;
}

.faq-item {
  background: rgba(255, 255, 255, 0.03);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  overflow: hidden;
  transition: border-color var(--transition);
}

.faq-item.open {
  border-color: rgba(76, 154, 255, 0.4);
}

.faq-question {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  width: 100%;
  padding: 20px 24px;
  font-size: 1rem;
  font-weight: 600;
  text-align: left;
  color: var(--text);
  background: transparent;
  border: none;
}

.faq-question .faq-icon {
  flex-shrink: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  width: 28px;
  height: 28px;
  color: var(--accent);
  transition: transform var(--transition);
}

.faq-item.open .faq-icon {
  transform: rotate(45deg);
}

.faq-answer {
  max-height: 0;
  overflow: hidden;
  transition: max-height var(--transition-slow);
}

.faq-answer p {
  padding: 0 24px 20px;
  font-size: 0.95rem;
}

/* ---------- 16. 表单 ---------- */
.form-group {
  margin-bottom: 20px;
}

.form-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 20px;
}

.form-group label {
  display: block;
  margin-bottom: 8px;
  font-size: 0.9rem;
  font-weight: 600;
  color: var(--text);
}

.form-group input,
.form-group select,
.form-group textarea {
  width: 100%;
  padding: 14px 16px;
  font-family: inherit;
  font-size: 0.95rem;
  color: var(--text);
  background: rgba(255, 255, 255, 0.04);
  border: 1px solid var(--border-strong);
  border-radius: var(--radius-sm);
  transition: all var(--transition);
}

.form-group input::placeholder,
.form-group textarea::placeholder {
  color: var(--text-muted);
}

.form-group input:focus,
.form-group select:focus,
.form-group textarea:focus {
  outline: none;
  border-color: var(--accent);
  box-shadow: 0 0 0 3px rgba(76, 154, 255, 0.2);
  background: rgba(255, 255, 255, 0.06);
}

.form-group select {
  appearance: none;
  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 fill='%239aa8c0' d='M6 8L0 0h12z'/%3E%3C/svg%3E");
  background-repeat: no-repeat;
  background-position: right 16px center;
}

.form-group select option {
  background: var(--surface-2);
  color: var(--text);
}

.form-group textarea {
  min-height: 140px;
  resize: vertical;
}

.form-error {
  margin-top: 6px;
  font-size: 0.82rem;
  color: var(--danger);
}

.form-group.has-error input,
.form-group.has-error select,
.form-group.has-error textarea {
  border-color: var(--danger);
}

.btn-submit {
  width: 100%;
}

.btn-submit[disabled] {
  opacity: 0.6;
  cursor: not-allowed;
  transform: none;
}

/* ---------- 17. 联系页 ---------- */
.contact-grid {
  display: grid;
  grid-template-columns: 5fr 7fr;
  gap: 40px;
  align-items: start;
}

.contact-info {
  display: grid;
  gap: 16px;
}

.info-item {
  display: flex;
  gap: 16px;
  align-items: flex-start;
  padding: 20px 24px;
  background: rgba(255, 255, 255, 0.03);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  transition: all var(--transition);
}

.info-item:hover {
  border-color: rgba(76, 154, 255, 0.35);
}

.info-icon {
  flex-shrink: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  width: 44px;
  height: 44px;
  color: var(--accent);
  background: var(--accent-soft);
  border-radius: var(--radius-sm);
}

.info-icon svg {
  width: 22px;
  height: 22px;
}

.info-item h4 {
  margin-bottom: 2px;
}

.info-item p,
.info-item a {
  font-size: 0.92rem;
  color: var(--text-secondary);
}

.wechat-card {
  text-align: center;
}

.wechat-card img {
  width: 140px;
  height: 140px;
  margin: 0 auto 12px;
  border-radius: var(--radius-sm);
  border: 1px solid var(--border);
}

.contact-form-card {
  padding: clamp(28px, 4vw, 48px);
  background: rgba(255, 255, 255, 0.03);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  backdrop-filter: blur(12px);
}

.map-card {
  margin-top: 40px;
  padding: 40px;
  text-align: center;
  background: rgba(255, 255, 255, 0.03);
  border: 1px dashed var(--border-strong);
  border-radius: var(--radius-lg);
}

/* ---------- 18. Toast 通知 ---------- */
.toast {
  position: fixed;
  top: calc(var(--header-height) + 16px);
  right: 24px;
  z-index: 300;
  display: flex;
  align-items: center;
  gap: 12px;
  max-width: 380px;
  padding: 16px 20px;
  font-size: 0.92rem;
  color: var(--text);
  background: var(--surface-2);
  border: 1px solid var(--border-strong);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-lg);
  transform: translateX(calc(100% + 32px));
  transition: transform var(--transition-slow);
}

.toast.show {
  transform: translateX(0);
}

.toast-success {
  border-left: 4px solid var(--success);
}

.toast-error {
  border-left: 4px solid var(--danger);
}

/* ---------- 19. CTA ---------- */
.cta-section {
  position: relative;
  padding: var(--section-spacing) 0;
  text-align: center;
  overflow: hidden;
  background: linear-gradient(135deg, #0b1e3e 0%, #071224 60%, #060a14 100%);
  border-top: 1px solid var(--border);
}

.cta-section .cta-bg {
  position: absolute;
  inset: 0;
  object-fit: cover;
  width: 100%;
  height: 100%;
  opacity: 0.5;
}

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

.cta-section p {
  max-width: 560px;
  margin: 0 auto 36px;
  font-size: 1.08rem;
}

/* ---------- 20. 页脚 ---------- */
.footer {
  padding: 72px 0 0;
  background: #04070d;
  border-top: 1px solid var(--border);
}

.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1.4fr;
  gap: 48px;
  padding-bottom: 48px;
}

.footer-brand img {
  height: 44px;
  width: auto;
  margin-bottom: 20px;
}

.footer-brand p {
  font-size: 0.9rem;
  max-width: 300px;
}

.footer h4 {
  margin-bottom: 20px;
  font-size: 0.95rem;
  letter-spacing: 0.04em;
}

.footer-links li {
  margin-bottom: 12px;
  font-size: 0.9rem;
  color: var(--text-secondary);
}

.footer-links a {
  color: var(--text-secondary);
}

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

.footer-bottom {
  padding: 24px 0;
  text-align: center;
  border-top: 1px solid var(--border);
}

.footer-bottom p {
  font-size: 0.85rem;
  color: var(--text-muted);
}

/* ---------- 21. 内页页头 ---------- */
.page-header {
  position: relative;
  padding: calc(var(--header-height) + 96px) 0 96px;
  text-align: center;
  overflow: hidden;
  background: radial-gradient(ellipse 80% 60% at 50% -10%, rgba(30, 95, 214, 0.35), transparent 70%);
}

.page-header h1 {
  margin-bottom: 16px;
  font-size: clamp(2.2rem, 5vw, 3.5rem);
}

.page-header p {
  max-width: 640px;
  margin: 0 auto;
  font-size: 1.08rem;
}

/* ---------- 22. 404 页 ---------- */
.error-page {
  min-height: 100vh;
  min-height: 100svh;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  padding: 48px 24px;
  text-align: center;
}

.error-code {
  font-size: clamp(6rem, 18vw, 12rem);
  font-weight: 800;
  line-height: 1;
  background: var(--gradient);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
  margin-bottom: 24px;
}

.error-page p {
  max-width: 440px;
  margin-bottom: 40px;
  font-size: 1.05rem;
}

.error-page .hero-buttons {
  justify-content: center;
}

/* ---------- 23. 滚动入场动画（仅在 JS 可用时隐藏初始态，无 JS 直接可见） ---------- */
@media (prefers-reduced-motion: no-preference) {
  .js .animate-on-scroll {
    opacity: 0;
    transform: translateY(30px);
    transition: opacity 0.6s ease, transform 0.6s cubic-bezier(0.4, 0, 0.2, 1);
  }

  .js .animate-on-scroll.visible {
    opacity: 1;
    transform: translateY(0);
  }
}

/* ---------- 24. 工具类 ---------- */
.mt-2 { margin-top: 16px; }
.mt-4 { margin-top: 32px; }
.text-center { text-align: center; }

/* ---------- 25. 响应式 ---------- */
@media (max-width: 1024px) {
  .grid-4 { grid-template-columns: repeat(2, 1fr); }
  .grid-3 { grid-template-columns: repeat(2, 1fr); }
  .clients-grid { grid-template-columns: repeat(3, 1fr); }
  .process-steps { grid-template-columns: repeat(3, 1fr); }
  .stats-grid { grid-template-columns: repeat(2, 1fr); }
  .footer-grid { grid-template-columns: repeat(2, 1fr); }
  .team-grid { grid-template-columns: repeat(2, 1fr); }

  /* 时间线改左侧竖线 */
  .timeline::before {
    left: 8px;
    transform: none;
  }

  .timeline-item,
  .timeline-item:nth-child(even) {
    width: 100%;
    left: 0;
    padding: 0 0 40px 40px;
  }

  .timeline-item::after,
  .timeline-item:nth-child(even)::after {
    left: 0;
    right: auto;
  }
}

@media (max-width: 768px) {
  .nav-toggle {
    display: flex;
  }

  .nav-links {
    position: fixed;
    top: var(--header-height);
    left: 0;
    right: 0;
    flex-direction: column;
    align-items: stretch;
    gap: 4px;
    padding: 16px 24px 24px;
    background: rgba(6, 10, 20, 0.97);
    backdrop-filter: blur(20px);
    border-bottom: 1px solid var(--border);
    transform: translateY(-120%);
    opacity: 0;
    visibility: hidden;
    transition: all var(--transition);
  }

  .nav-links.active {
    transform: translateY(0);
    opacity: 1;
    visibility: visible;
  }

  .nav-links a {
    padding: 14px 16px;
    border-radius: var(--radius-sm);
  }

  .nav-links a::after {
    display: none;
  }

  .nav-links a:hover,
  .nav-links a.active {
    background: var(--accent-soft);
  }

  .nav-cta {
    margin: 8px 0 0;
  }

  .grid-2,
  .grid-3,
  .grid-4,
  .bento-grid,
  .stats-grid,
  .clients-grid,
  .process-steps,
  .team-grid,
  .footer-grid,
  .showcase,
  .contact-grid,
  .form-row {
    grid-template-columns: 1fr;
  }

  .showcase.reverse .showcase-media {
    order: 0;
  }

  .showcase + .showcase {
    margin-top: 64px;
  }

  .hero {
    min-height: auto;
    padding-bottom: 80px;
  }

  .hero-buttons .btn {
    flex: 1 1 auto;
  }

  .section-header {
    margin-bottom: 40px;
  }

  .toast {
    left: 24px;
    max-width: none;
  }
}

@media (max-width: 480px) {
  .clients-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .btn {
    padding: 13px 24px;
  }

  .stat-item {
    padding: 24px 12px;
  }
}