/* ========================================
   嘉兴嘉瓷科技有限公司 - 企业官网样式
   风格：嘉瓷陶艺风（泥料黄 · 陶土棕 · 米纸底）
   ======================================== */

/* ---------- CSS 变量 ---------- */
:root {
  --color-primary: #5C3F14;
  --color-primary-light: #7D571A;
  --color-accent: #C9972B;
  --color-accent-light: #D5B166;
  --color-accent-bg: rgba(201, 151, 43, 0.12);
  --color-bg: #FDF8EC;
  --color-bg-alt: #FBF3DF;
  --color-bg-dark: #2E2412;
  --color-text: #3B2C10;
  --color-text-light: #6B5527;
  --color-text-white: #FDF8EC;
  --color-border: #E5D3A5;
  --font-family: 'Noto Sans SC', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  --font-serif: 'Noto Serif SC', 'Songti SC', 'STSong', 'SimSun', serif;
  --header-height: 72px;
  --container-max: 1200px;
  --radius: 10px;
  --radius-lg: 18px;
  --shadow-sm: 0 1px 3px rgba(93,66,16,0.08);
  --shadow-md: 0 4px 16px rgba(93,66,16,0.12);
  --shadow-lg: 0 8px 32px rgba(93,66,16,0.16);
  --transition: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

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

html {
  scroll-behavior: smooth;
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  font-family: var(--font-family);
  color: var(--color-text);
  background: var(--color-bg);
  line-height: 1.7;
  overflow-x: hidden;
}

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

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

ul {
  list-style: none;
}

button {
  border: none;
  background: none;
  cursor: pointer;
  font-family: inherit;
}

input, select, textarea {
  font-family: inherit;
  font-size: inherit;
}

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

/* ---------- 通用按钮 ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 12px 32px;
  border-radius: var(--radius);
  font-weight: 500;
  font-size: 15px;
  transition: all var(--transition);
  cursor: pointer;
  letter-spacing: 0.5px;
}

.btn-primary {
  background: var(--color-accent);
  color: #2E2208;
  border: 2px solid var(--color-accent);
}

.btn-primary:hover {
  background: var(--color-accent-light);
  border-color: var(--color-accent-light);
  transform: translateY(-2px);
  box-shadow: 0 4px 16px rgba(201, 151, 43, 0.35);
}

.btn-outline {
  background: transparent;
  color: #fff;
  border: 2px solid rgba(255,255,255,0.6);
}

.btn-outline:hover {
  background: rgba(255,255,255,0.1);
  border-color: #fff;
  transform: translateY(-2px);
}

.btn-outline-clay {
  background: transparent;
  color: var(--color-accent);
  border: 2px solid var(--color-accent);
}

.btn-outline-clay:hover {
  background: var(--color-accent);
  color: #2E2208;
  transform: translateY(-2px);
  box-shadow: 0 4px 16px rgba(201, 151, 43, 0.3);
}

.btn-sm {
  padding: 10px 24px;
  font-size: 14px;
}

.btn-block {
  width: 100%;
}

/* ---------- 通用板块 ---------- */
.section {
  padding: 100px 0;
}

.section-header {
  text-align: center;
  margin-bottom: 60px;
}

.section-tag {
  display: inline-block;
  padding: 4px 16px;
  background: var(--color-accent-bg);
  color: var(--color-accent);
  border-radius: 20px;
  font-size: 13px;
  font-weight: 500;
  letter-spacing: 1px;
  margin-bottom: 16px;
}

.section-title {
  font-size: 36px;
  font-weight: 700;
  font-family: var(--font-serif);
  color: var(--color-primary);
  margin-bottom: 16px;
  line-height: 1.3;
  letter-spacing: 1px;
}

.section-desc {
  font-size: 16px;
  color: var(--color-text-light);
  max-width: 640px;
  margin: 0 auto;
  line-height: 1.8;
}

/* ---------- 渐入动画 ---------- */
.fade-up {
  opacity: 0;
  transform: translateY(30px);
  transition: opacity 0.7s ease, transform 0.7s ease;
}

.fade-up.visible {
  opacity: 1;
  transform: translateY(0);
}

.fade-up.delay-1 { transition-delay: 0.15s; }
.fade-up.delay-2 { transition-delay: 0.3s; }
.fade-up.delay-3 { transition-delay: 0.45s; }

/* ========================================
   Header 导航
   ======================================== */
.header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  height: var(--header-height);
  z-index: 1000;
  transition: background var(--transition), box-shadow var(--transition);
}

.header.scrolled {
  background: rgba(253, 248, 236, 0.95);
  backdrop-filter: blur(12px);
  box-shadow: var(--shadow-sm);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 100%;
}

.logo {
  display: flex;
  align-items: center;
  gap: 10px;
  z-index: 1001;
}

.logo-text {
  font-size: 20px;
  font-weight: 700;
  font-family: var(--font-serif);
  color: var(--color-primary);
  letter-spacing: 2px;
}

.header:not(.scrolled) .logo-text {
  color: #fff;
}

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

.nav-link {
  padding: 8px 16px;
  font-size: 14px;
  font-weight: 400;
  color: var(--color-text-light);
  border-radius: var(--radius);
  transition: all var(--transition);
  position: relative;
}

.nav-link::after {
  content: '';
  position: absolute;
  bottom: 2px;
  left: 50%;
  width: 0;
  height: 2px;
  background: var(--color-accent);
  transition: all var(--transition);
  transform: translateX(-50%);
}

.nav-link:hover,
.nav-link.active {
  color: var(--color-accent);
}

.nav-link:hover::after,
.nav-link.active::after {
  width: 60%;
}

.header:not(.scrolled) .nav-link {
  color: rgba(255,255,255,0.8);
}

.header:not(.scrolled) .nav-link:hover,
.header:not(.scrolled) .nav-link.active {
  color: #fff;
}

.header:not(.scrolled) .nav-link::after {
  background: #fff;
}

/* 移动端菜单按钮 */
.menu-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  padding: 8px;
  z-index: 1001;
}

.menu-toggle span {
  display: block;
  width: 22px;
  height: 2px;
  background: var(--color-primary);
  border-radius: 2px;
  transition: all var(--transition);
}

.header:not(.scrolled) .menu-toggle span {
  background: #fff;
}

.menu-toggle.active span:nth-child(1) {
  transform: rotate(45deg) translate(5px, 5px);
}

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

.menu-toggle.active span:nth-child(3) {
  transform: rotate(-45deg) translate(5px, -5px);
}

/* ========================================
   Hero 首页横幅
   ======================================== */
.hero {
  position: relative;
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  overflow: hidden;
}

.hero-bg {
  position: absolute;
  inset: 0;
  background:
    linear-gradient(135deg, #2E2412 0%, #4A3515 40%, #5C3F14 70%, #2E2412 100%);
  z-index: 0;
}

.hero-bg::before {
  content: '';
  position: absolute;
  inset: 0;
  background:
    radial-gradient(ellipse at 20% 50%, rgba(201, 151, 43, 0.28) 0%, transparent 60%),
    radial-gradient(ellipse at 80% 20%, rgba(213, 177, 102, 0.18) 0%, transparent 50%),
    radial-gradient(ellipse at 60% 80%, rgba(201, 151, 43, 0.16) 0%, transparent 40%);
}

.hero-bg::after {
  content: '';
  position: absolute;
  inset: 0;
  background-image:
    radial-gradient(circle at 25% 25%, rgba(255,255,255,0.02) 1px, transparent 1px),
    radial-gradient(circle at 75% 75%, rgba(255,255,255,0.02) 1px, transparent 1px);
  background-size: 60px 60px;
}

.hero-overlay {
  position: absolute;
  inset: 0;
  background: linear-gradient(180deg, transparent 60%, rgba(46,36,18,0.45) 100%);
  z-index: 1;
}

.hero-content {
  position: relative;
  z-index: 2;
  text-align: center;
  padding: 120px 24px 80px;
}

.hero-title {
  font-size: 64px;
  font-weight: 900;
  font-family: var(--font-serif);
  color: #FDF8EC;
  letter-spacing: 8px;
  margin-bottom: 20px;
  line-height: 1.2;
}

.hero-subtitle {
  font-size: 20px;
  color: rgba(255,255,255,0.75);
  margin-bottom: 40px;
  letter-spacing: 2px;
  font-weight: 300;
}

.hero-actions {
  display: flex;
  gap: 16px;
  justify-content: center;
  margin-bottom: 60px;
}

.hero-stats {
  display: flex;
  justify-content: center;
  gap: 48px;
  padding-top: 40px;
  border-top: 1px solid rgba(255,255,255,0.1);
}

.stat-item {
  text-align: center;
}

.stat-num {
  font-size: 40px;
  font-weight: 700;
  color: var(--color-accent-light);
  line-height: 1;
}

.stat-unit {
  font-size: 18px;
  color: var(--color-accent-light);
  font-weight: 500;
}

.stat-label {
  display: block;
  font-size: 13px;
  color: rgba(255,255,255,0.5);
  margin-top: 8px;
  letter-spacing: 1px;
}

.scroll-down {
  position: absolute;
  bottom: 32px;
  left: 50%;
  transform: translateX(-50%);
  z-index: 2;
  color: rgba(255,255,255,0.5);
  animation: bounce 2s infinite;
}

@keyframes bounce {
  0%, 20%, 50%, 80%, 100% { transform: translateX(-50%) translateY(0); }
  40% { transform: translateX(-50%) translateY(-8px); }
  60% { transform: translateX(-50%) translateY(-4px); }
}

/* ========================================
   公司简介
   ======================================== */
.intro {
  background: var(--color-bg);
}

.intro-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
}

.intro-card {
  padding: 36px 28px;
  border-radius: var(--radius-lg);
  background: var(--color-bg);
  border: 1px solid var(--color-border);
  transition: all var(--transition);
}

.intro-card:hover {
  transform: translateY(-6px);
  box-shadow: var(--shadow-lg);
  border-color: var(--color-accent);
}

.intro-icon {
  margin-bottom: 20px;
}

.intro-card h3 {
  font-size: 18px;
  font-weight: 600;
  color: var(--color-primary);
  margin-bottom: 12px;
}

.intro-card p {
  font-size: 14px;
  color: var(--color-text-light);
  line-height: 1.8;
}

/* ========================================
   技术原理
   ======================================== */
.technology {
  background: var(--color-bg-alt);
}

.tech-flow {
  display: flex;
  align-items: flex-start;
  justify-content: center;
  gap: 0;
  margin-bottom: 60px;
  overflow-x: auto;
  padding-bottom: 8px;
}

.tech-step {
  flex: 0 0 auto;
  width: 180px;
  text-align: center;
  padding: 24px 16px;
}

.step-number {
  width: 48px;
  height: 48px;
  border-radius: 50%;
  background: var(--color-accent);
  color: #2E2208;
  font-size: 16px;
  font-weight: 700;
  display: flex;
  align-items: center;
  justify-content: center;
  margin: 0 auto 16px;
}

.step-content h3 {
  font-size: 16px;
  font-weight: 600;
  color: var(--color-primary);
  margin-bottom: 8px;
}

.step-content p {
  font-size: 13px;
  color: var(--color-text-light);
  line-height: 1.7;
}

.tech-connector {
  flex: 0 0 auto;
  width: 40px;
  height: 2px;
  background: linear-gradient(90deg, var(--color-accent), var(--color-accent-light));
  margin-top: 46px;
  border-radius: 1px;
  position: relative;
}

.tech-connector::after {
  content: '';
  position: absolute;
  right: -4px;
  top: -3px;
  width: 0;
  height: 0;
  border-left: 6px solid var(--color-accent-light);
  border-top: 4px solid transparent;
  border-bottom: 4px solid transparent;
}

.tech-features {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
}

.tech-feature-card {
  padding: 28px 24px;
  background: var(--color-bg);
  border-radius: var(--radius-lg);
  text-align: center;
  border: 1px solid var(--color-border);
  transition: all var(--transition);
}

.tech-feature-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-md);
}

.tech-feature-card .feature-icon {
  color: var(--color-accent);
  margin-bottom: 16px;
}

.tech-feature-card h4 {
  font-size: 16px;
  font-weight: 600;
  color: var(--color-primary);
  margin-bottom: 8px;
}

.tech-feature-card p {
  font-size: 13px;
  color: var(--color-text-light);
  line-height: 1.7;
}

/* ========================================
   产品中心
   ======================================== */
.products {
  background: var(--color-bg);
}

.product-showcase {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 32px;
  margin-bottom: 60px;
}

.product-card {
  border-radius: var(--radius-lg);
  overflow: hidden;
  border: 1px solid var(--color-border);
  background: var(--color-bg);
  transition: all var(--transition);
}

.product-card:hover {
  transform: translateY(-6px);
  box-shadow: var(--shadow-lg);
}

.product-visual {
  position: relative;
  background: linear-gradient(135deg, var(--color-bg-alt) 0%, #F2E7C8 100%);
  padding: 32px;
  display: flex;
  align-items: center;
  justify-content: center;
  min-height: 280px;
}

.product-img-placeholder {
  width: 100%;
  max-width: 300px;
}

.product-img {
  width: 100%;
  max-width: 320px;
  height: auto;
  object-fit: contain;
  border-radius: var(--radius);
}

.product-badge {
  position: absolute;
  top: 16px;
  right: 16px;
  padding: 4px 14px;
  background: var(--color-accent);
  color: #fff;
  border-radius: 20px;
  font-size: 12px;
  font-weight: 500;
}

.badge-pro {
  background: var(--color-primary);
}

.product-info {
  padding: 28px;
}

.product-name {
  font-size: 22px;
  font-weight: 700;
  font-family: var(--font-serif);
  color: var(--color-primary);
  margin-bottom: 8px;
}

.product-desc {
  font-size: 14px;
  color: var(--color-text-light);
  margin-bottom: 20px;
  line-height: 1.7;
}

.product-specs {
  margin-bottom: 20px;
}

.spec-row {
  display: flex;
  justify-content: space-between;
  padding: 8px 0;
  border-bottom: 1px solid var(--color-border);
  font-size: 13px;
}

.spec-row:last-child {
  border-bottom: none;
}

.spec-label {
  color: var(--color-text-light);
  flex-shrink: 0;
}

.spec-value {
  color: var(--color-primary);
  font-weight: 500;
  text-align: right;
}

/* 参数对比表 */
.compare-table {
  background: var(--color-bg-alt);
  border-radius: var(--radius-lg);
  padding: 40px;
}

.compare-title {
  font-size: 20px;
  font-weight: 600;
  color: var(--color-primary);
  margin-bottom: 24px;
  text-align: center;
}

.table-wrapper {
  overflow-x: auto;
}

.compare-table table {
  width: 100%;
  border-collapse: collapse;
  font-size: 14px;
}

.compare-table thead th {
  background: var(--color-primary);
  color: #fff;
  padding: 14px 20px;
  text-align: left;
  font-weight: 500;
  white-space: nowrap;
}

.compare-table thead th:first-child {
  border-radius: var(--radius) 0 0 0;
}

.compare-table thead th:last-child {
  border-radius: 0 var(--radius) 0 0;
}

.compare-table tbody td {
  padding: 12px 20px;
  border-bottom: 1px solid var(--color-border);
}

.compare-table tbody tr:hover {
  background: rgba(201, 151, 43, 0.06);
}

.compare-table tbody td:first-child {
  font-weight: 500;
  color: var(--color-primary);
}

/* ========================================
   应用场景
   ======================================== */
.applications {
  background: var(--color-bg-alt);
}

.app-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
}

.app-card {
  background: var(--color-bg);
  border-radius: var(--radius-lg);
  padding: 32px 24px;
  border: 1px solid var(--color-border);
  transition: all var(--transition);
}

.app-card:hover {
  transform: translateY(-6px);
  box-shadow: var(--shadow-lg);
  border-color: var(--color-accent);
}

.app-icon {
  margin-bottom: 20px;
}

.app-card h3 {
  font-size: 20px;
  font-weight: 600;
  color: var(--color-primary);
  margin-bottom: 12px;
}

.app-card > p {
  font-size: 14px;
  color: var(--color-text-light);
  line-height: 1.8;
  margin-bottom: 16px;
}

.app-list {
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.app-list li {
  font-size: 13px;
  color: var(--color-text-light);
  padding-left: 16px;
  position: relative;
}

.app-list li::before {
  content: '';
  position: absolute;
  left: 0;
  top: 8px;
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--color-accent);
}

/* ========================================
   行业趋势
   ======================================== */
.trends {
  background: var(--color-bg);
}

.chart-area {
  background: var(--color-bg-alt);
  border-radius: var(--radius-lg);
  padding: 40px;
  margin-bottom: 32px;
}

.chart-title {
  font-size: 16px;
  font-weight: 600;
  color: var(--color-primary);
  margin-bottom: 32px;
  text-align: center;
}

.bar-chart {
  display: flex;
  align-items: flex-end;
  justify-content: center;
  gap: 20px;
  height: 260px;
  padding: 0 20px;
}

.bar-group {
  display: flex;
  flex-direction: column;
  align-items: center;
  flex: 1;
  max-width: 80px;
}

.bar {
  width: 100%;
  height: var(--bar-height);
  background: linear-gradient(180deg, var(--color-accent) 0%, var(--color-accent-light) 100%);
  border-radius: 6px 6px 0 0;
  position: relative;
  transition: height 1.2s cubic-bezier(0.4, 0, 0.2, 1);
  min-height: 4px;
}

.bar-projected {
  background: linear-gradient(180deg, var(--color-primary-light) 0%, var(--color-primary) 100%);
  opacity: 0.7;
  border: 2px dashed var(--color-primary-light);
  background-clip: padding-box;
}

.bar-val {
  position: absolute;
  top: -28px;
  left: 50%;
  transform: translateX(-50%);
  font-size: 13px;
  font-weight: 600;
  color: var(--color-primary);
  white-space: nowrap;
}

.bar-year {
  margin-top: 10px;
  font-size: 12px;
  color: var(--color-text-light);
  font-weight: 500;
}

.chart-note {
  text-align: center;
  font-size: 12px;
  color: var(--color-text-light);
  margin-top: 24px;
  opacity: 0.7;
}

.trends-highlights {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
  margin-bottom: 40px;
}

.highlight-card {
  background: var(--color-bg-alt);
  border-radius: var(--radius-lg);
  padding: 32px;
  text-align: center;
  border: 1px solid var(--color-border);
}

.highlight-num {
  font-size: 36px;
  font-weight: 700;
  color: var(--color-accent);
  line-height: 1;
  margin-bottom: 8px;
}

.highlight-label {
  font-size: 14px;
  color: var(--color-text-light);
  line-height: 1.6;
}

.highlight-label span {
  font-size: 12px;
  opacity: 0.7;
}

.trends-drivers h4 {
  font-size: 18px;
  font-weight: 600;
  color: var(--color-primary);
  margin-bottom: 20px;
  text-align: center;
}

.driver-list {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 16px;
}

.driver-item {
  display: flex;
  gap: 16px;
  padding: 20px;
  background: var(--color-bg-alt);
  border-radius: var(--radius);
  border: 1px solid var(--color-border);
}

.driver-tag {
  flex-shrink: 0;
  padding: 4px 12px;
  background: var(--color-accent-bg);
  color: var(--color-accent);
  border-radius: 4px;
  font-size: 12px;
  font-weight: 600;
  height: fit-content;
  white-space: nowrap;
}

.driver-item p {
  font-size: 13px;
  color: var(--color-text-light);
  line-height: 1.7;
}

/* ========================================
   在线建模
   ======================================== */
.modeling {
  background: var(--color-bg);
}

.modeling-content {
  display: flex;
  flex-direction: column;
  gap: 40px;
}

.modeling-preview {
  position: relative;
  border-radius: var(--radius-lg);
  overflow: hidden;
  background: var(--color-bg-alt);
}

.preview-frame {
  width: 100%;
  aspect-ratio: 16/9;
  display: flex;
  align-items: center;
  justify-content: center;
}

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

.preview-overlay {
  position: absolute;
  bottom: 0;
  left: 0;
  right: 0;
  background: linear-gradient(180deg, transparent 0%, rgba(46, 36, 18, 0.88) 100%);
  padding: 40px 32px 24px;
}

.preview-info h3 {
  font-size: 22px;
  font-weight: 600;
  color: #fff;
  margin-bottom: 8px;
}

.preview-info p {
  font-size: 14px;
  color: rgba(255,255,255,0.8);
}

.modeling-features {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
}

.modeling-feature-card {
  padding: 28px 24px;
  background: var(--color-bg-alt);
  border-radius: var(--radius-lg);
  text-align: center;
  border: 1px solid var(--color-border);
  transition: all var(--transition);
}

.modeling-feature-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-md);
  border-color: var(--color-accent);
}

.modeling-feature-card .feature-icon {
  color: var(--color-accent);
  margin-bottom: 16px;
}

.modeling-feature-card h4 {
  font-size: 16px;
  font-weight: 600;
  color: var(--color-primary);
  margin-bottom: 8px;
}

.modeling-feature-card p {
  font-size: 13px;
  color: var(--color-text-light);
  line-height: 1.7;
}

.modeling-actions {
  text-align: center;
  padding-top: 20px;
}

.btn-lg {
  padding: 16px 48px;
  font-size: 16px;
}

.modeling-tip {
  font-size: 13px;
  color: var(--color-text-light);
  margin-top: 16px;
  opacity: 0.7;
}

/* ========================================
   常见问题
   ======================================== */
.faq {
  background: var(--color-bg-alt);
}

.faq-list {
  max-width: 800px;
  margin: 0 auto;
}

.faq-item {
  background: var(--color-bg);
  border-radius: var(--radius);
  margin-bottom: 12px;
  border: 1px solid var(--color-border);
  overflow: hidden;
  transition: all var(--transition);
}

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

.faq-item.active {
  border-color: var(--color-accent);
  box-shadow: var(--shadow-sm);
}

.faq-question {
  width: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 18px 24px;
  font-size: 15px;
  font-weight: 500;
  color: var(--color-primary);
  text-align: left;
  transition: all var(--transition);
}

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

.faq-arrow {
  flex-shrink: 0;
  transition: transform var(--transition);
  color: var(--color-text-light);
}

.faq-item.active .faq-arrow {
  transform: rotate(180deg);
  color: var(--color-accent);
}

.faq-answer {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.4s ease, padding 0.4s ease;
}

.faq-item.active .faq-answer {
  max-height: 400px;
}

.faq-answer p {
  padding: 0 24px 20px;
  font-size: 14px;
  color: var(--color-text-light);
  line-height: 1.9;
}

/* ========================================
   关于我们
   ======================================== */
.about {
  background: var(--color-bg);
}

.about-content {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 60px;
  align-items: start;
}

.about-lead {
  font-size: 18px;
  font-weight: 500;
  font-family: var(--font-serif);
  color: var(--color-primary);
  line-height: 1.8;
  margin-bottom: 16px;
}

.about-text p {
  font-size: 15px;
  color: var(--color-text-light);
  line-height: 1.9;
  margin-bottom: 16px;
}

.about-milestones {
  position: relative;
  padding-left: 32px;
}

.about-milestones::before {
  content: '';
  position: absolute;
  left: 7px;
  top: 0;
  bottom: 0;
  width: 2px;
  background: linear-gradient(180deg, var(--color-accent), var(--color-accent-light));
  border-radius: 1px;
}

.milestone {
  position: relative;
  padding: 12px 0;
  padding-left: 24px;
}

.milestone::before {
  content: '';
  position: absolute;
  left: -28px;
  top: 18px;
  width: 12px;
  height: 12px;
  border-radius: 50%;
  background: var(--color-bg);
  border: 3px solid var(--color-accent);
}

.milestone-year {
  display: inline-block;
  font-size: 14px;
  font-weight: 700;
  color: var(--color-accent);
  margin-bottom: 4px;
}

.milestone-event {
  display: block;
  font-size: 14px;
  color: var(--color-text-light);
}

/* ========================================
   联系我们
   ======================================== */
.contact {
  background: var(--color-bg-alt);
}

.contact-content {
  display: grid;
  grid-template-columns: 1fr 1.2fr;
  gap: 48px;
  align-items: start;
}

.contact-info {
  display: flex;
  flex-direction: column;
  gap: 24px;
}

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

.contact-icon {
  flex-shrink: 0;
  width: 48px;
  height: 48px;
  border-radius: var(--radius);
  background: var(--color-accent-bg);
  color: var(--color-accent);
  display: flex;
  align-items: center;
  justify-content: center;
}

.contact-item h4 {
  font-size: 15px;
  font-weight: 600;
  color: var(--color-primary);
  margin-bottom: 4px;
}

.contact-item p {
  font-size: 14px;
  color: var(--color-text-light);
  line-height: 1.6;
}

.contact-social {
  margin-top: 28px;
  padding-top: 24px;
  border-top: 1px solid var(--color-border);
}

.contact-social h4 {
  font-size: 16px;
  font-weight: 600;
  color: var(--color-primary);
  margin-bottom: 16px;
}

.social-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 12px;
}

.social-item {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 8px;
  padding: 14px 8px;
  border-radius: var(--radius);
  border: 1px solid var(--color-border);
  transition: all var(--transition);
  text-align: center;
}

.social-item:hover {
  transform: translateY(-3px);
  box-shadow: var(--shadow-md);
  border-color: var(--color-accent);
}

.social-icon {
  width: 44px;
  height: 44px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: all var(--transition);
}

.social-wechat { background: rgba(7, 193, 96, 0.1); color: #07c160; }
.social-wechat:hover { background: #07c160; color: #fff; }

.social-wechat-video { background: rgba(7, 193, 96, 0.1); color: #07c160; }
.social-wechat-video:hover { background: #07c160; color: #fff; }

.social-douyin { background: rgba(30, 30, 30, 0.08); color: #1e1e1e; }
.social-douyin:hover { background: #1e1e1e; color: #fff; }

.social-xiaohongshu { background: rgba(255, 42, 62, 0.08); color: #ff2a3e; }
.social-xiaohongshu:hover { background: #ff2a3e; color: #fff; }

.social-tiktok { background: rgba(0, 242, 234, 0.08); color: #00f2ea; }
.social-tiktok:hover { background: #010101; color: #00f2ea; }

.social-facebook { background: rgba(24, 119, 242, 0.08); color: #1877f2; }
.social-facebook:hover { background: #1877f2; color: #fff; }

.social-youtube { background: rgba(255, 0, 0, 0.08); color: #ff0000; }
.social-youtube:hover { background: #ff0000; color: #fff; }

.social-name {
  font-size: 11px;
  color: var(--color-text-light);
  font-weight: 500;
  white-space: nowrap;
}

.social-item:hover .social-name {
  color: var(--color-accent);
}

.social-account {
  font-size: 10px;
  color: var(--color-text-light);
  opacity: 0.7;
  margin-top: 2px;
}

.social-item:hover .social-account {
  opacity: 1;
  color: var(--color-accent);
}

/* 二维码弹窗 */
.qrcode-modal {
  display: none;
  position: fixed;
  inset: 0;
  background: rgba(0,0,0,0.6);
  z-index: 2000;
  align-items: center;
  justify-content: center;
}

.qrcode-modal.active {
  display: flex;
}

.qrcode-content {
  background: var(--color-bg);
  padding: 32px;
  border-radius: var(--radius-lg);
  text-align: center;
  max-width: 320px;
  position: relative;
  animation: qrcodeIn 0.3s ease;
}

@keyframes qrcodeIn {
  from { opacity: 0; transform: scale(0.9); }
  to { opacity: 1; transform: scale(1); }
}

.qrcode-close {
  position: absolute;
  top: 12px;
  right: 12px;
  width: 28px;
  height: 28px;
  border-radius: 50%;
  background: var(--color-bg-alt);
  color: var(--color-text-light);
  font-size: 18px;
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  transition: all var(--transition);
}

.qrcode-close:hover {
  background: var(--color-accent);
  color: #2E2208;
}

.qrcode-img {
  width: 200px;
  height: 200px;
  object-fit: contain;
  margin-bottom: 16px;
  border-radius: var(--radius);
}

.qrcode-platform {
  font-size: 16px;
  font-weight: 600;
  color: var(--color-primary);
  margin-bottom: 4px;
}

.qrcode-account {
  font-size: 14px;
  color: var(--color-accent);
  margin-bottom: 8px;
}

.qrcode-tip {
  font-size: 12px;
  color: var(--color-text-light);
  opacity: 0.7;
}

.contact-form-wrapper {
  background: var(--color-bg);
  border-radius: var(--radius-lg);
  padding: 36px;
  box-shadow: var(--shadow-md);
}

.form-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
}

.form-group {
  margin-bottom: 16px;
}

.form-group label {
  display: block;
  font-size: 14px;
  font-weight: 500;
  color: var(--color-primary);
  margin-bottom: 6px;
}

.form-group input,
.form-group select,
.form-group textarea {
  width: 100%;
  padding: 10px 14px;
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  font-size: 14px;
  color: var(--color-text);
  background: var(--color-bg);
  transition: border-color var(--transition), box-shadow var(--transition);
  outline: none;
}

.form-group input:focus,
.form-group select:focus,
.form-group textarea:focus {
  border-color: var(--color-accent);
  box-shadow: 0 0 0 3px rgba(201, 151, 43, 0.15);
}

.form-group textarea {
  resize: vertical;
  min-height: 100px;
}

.form-group select {
  appearance: none;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='12' viewBox='0 0 24 24'%3E%3Cpath d='M6 9l6 6 6-6' fill='none' stroke='%23636e72' stroke-width='2'/%3E%3C/svg%3E");
  background-repeat: no-repeat;
  background-position: right 12px center;
  padding-right: 36px;
}

/* ========================================
   页脚
   ======================================== */
.footer {
  background: var(--color-bg-dark);
  color: rgba(255,255,255,0.6);
  padding: 60px 0 0;
}

.footer-grid {
  display: grid;
  grid-template-columns: 1.5fr 1fr 1fr 1fr;
  gap: 40px;
  padding-bottom: 40px;
  border-bottom: 1px solid rgba(255,255,255,0.08);
}

.footer-logo {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-bottom: 16px;
}

.footer-logo span {
  font-size: 18px;
  font-weight: 700;
  font-family: var(--font-serif);
  color: #FDF8EC;
  letter-spacing: 2px;
}

.footer-brand p {
  font-size: 13px;
  line-height: 1.8;
}

.footer-links h4 {
  font-size: 15px;
  font-weight: 600;
  font-family: var(--font-serif);
  color: #FDF8EC;
  margin-bottom: 16px;
}

.footer-links a,
.footer-links p {
  display: block;
  font-size: 13px;
  color: rgba(255,255,255,0.5);
  margin-bottom: 8px;
  transition: color var(--transition);
}

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

.footer-bottom {
  text-align: center;
  padding: 20px 0;
  font-size: 12px;
  opacity: 0.5;
}

/* ========================================
   回到顶部
   ======================================== */
.back-to-top {
  position: fixed;
  bottom: 32px;
  right: 32px;
  width: 44px;
  height: 44px;
  border-radius: 50%;
  background: var(--color-accent);
  color: #2E2208;
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: var(--shadow-md);
  opacity: 0;
  visibility: hidden;
  transform: translateY(16px);
  transition: all var(--transition);
  z-index: 999;
}

.back-to-top.visible {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}

.back-to-top:hover {
  background: var(--color-accent-light);
  transform: translateY(-4px);
}

/* ========================================
   响应式 - 平板
   ======================================== */
@media (max-width: 1024px) {
  .intro-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .tech-flow {
    flex-wrap: wrap;
    justify-content: center;
    gap: 8px;
  }

  .tech-connector {
    display: none;
  }

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

  .product-showcase {
    grid-template-columns: 1fr;
    max-width: 600px;
    margin-left: auto;
    margin-right: auto;
  }

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

  .about-content {
    grid-template-columns: 1fr;
    gap: 40px;
  }

  .contact-content {
    grid-template-columns: 1fr;
    gap: 32px;
  }

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

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

/* ========================================
   响应式 - 手机
   ======================================== */
@media (max-width: 768px) {
  :root {
    --header-height: 60px;
  }

  .section {
    padding: 60px 0;
  }

  .section-title {
    font-size: 26px;
  }

  .section-desc {
    font-size: 14px;
  }

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

  /* 导航移动端 */
  .menu-toggle {
    display: flex;
  }

  .nav {
    position: fixed;
    top: 0;
    right: -100%;
    width: 280px;
    height: 100vh;
    background: var(--color-bg);
    flex-direction: column;
    padding: 80px 24px 24px;
    gap: 4px;
    box-shadow: -4px 0 24px rgba(0,0,0,0.1);
    transition: right var(--transition);
    z-index: 1000;
  }

  .nav.open {
    right: 0;
  }

  .nav-link {
    width: 100%;
    padding: 12px 16px;
    font-size: 15px;
    color: var(--color-text);
  }

  .header:not(.scrolled) .nav-link {
    color: var(--color-text);
  }

  .header:not(.scrolled) .nav-link:hover,
  .header:not(.scrolled) .nav-link.active {
    color: var(--color-accent);
  }

  .header:not(.scrolled) .nav-link::after {
    background: var(--color-accent);
  }

  .menu-toggle.active span {
    background: var(--color-primary);
  }

  /* Hero */
  .hero-title {
    font-size: 36px;
    letter-spacing: 4px;
  }

  .hero-subtitle {
    font-size: 15px;
    letter-spacing: 1px;
  }

  .hero-actions {
    flex-direction: column;
    align-items: center;
    gap: 12px;
  }

  .hero-stats {
    flex-wrap: wrap;
    gap: 24px;
  }

  .stat-item {
    flex: 0 0 calc(50% - 12px);
  }

  .stat-num {
    font-size: 28px;
  }

  /* 简介 */
  .intro-grid {
    grid-template-columns: 1fr;
  }

  /* 技术流程 */
  .tech-step {
    width: 140px;
  }

  .tech-features {
    grid-template-columns: 1fr;
  }

  /* 产品 */
  .product-showcase {
    max-width: 100%;
  }

  .compare-table {
    padding: 20px;
  }

  /* 应用 */
  .app-grid {
    grid-template-columns: 1fr;
  }

  /* 趋势 */
  .bar-chart {
    gap: 8px;
    height: 200px;
  }

  .bar-group {
    max-width: 50px;
  }

  .bar-val {
    font-size: 11px;
  }

  .trends-highlights {
    grid-template-columns: 1fr;
    gap: 12px;
  }

  .driver-list {
    grid-template-columns: 1fr;
  }

  /* 在线建模 */
  .modeling-features {
    grid-template-columns: 1fr;
    gap: 12px;
  }

  .modeling-feature-card {
    padding: 20px 16px;
  }

  .preview-overlay {
    padding: 24px 16px 16px;
  }

  .preview-info h3 {
    font-size: 18px;
  }

  .btn-lg {
    padding: 14px 32px;
    font-size: 15px;
  }

  /* 关于 */
  .about-content {
    gap: 32px;
  }

  /* 联系 */
  .form-row {
    grid-template-columns: 1fr;
  }

  .social-grid {
    grid-template-columns: repeat(4, 1fr);
    gap: 8px;
  }

  .social-item {
    padding: 10px 4px;
  }

  .social-icon {
    width: 36px;
    height: 36px;
  }

  .social-icon svg {
    width: 18px;
    height: 18px;
  }

  .social-name {
    font-size: 10px;
  }

  .contact-form-wrapper {
    padding: 24px;
  }

  /* 页脚 */
  .footer-grid {
    grid-template-columns: 1fr;
    gap: 24px;
  }

  .back-to-top {
    bottom: 20px;
    right: 20px;
    width: 40px;
    height: 40px;
  }
}

/* ========================================
   辅助 - 移动端遮罩
   ======================================== */
.nav-overlay {
  display: none;
  position: fixed;
  inset: 0;
  background: rgba(0,0,0,0.4);
  z-index: 999;
}

.nav-overlay.active {
  display: block;
}

/* ========================================
   柱状图动画
   ======================================== */
.bar-chart .bar {
  height: 0 !important;
}

.bar-chart.animated .bar {
  height: var(--bar-height) !important;
}

/* ========================================
   表单提交成功提示
   ======================================== */
.form-success {
  display: none;
  text-align: center;
  padding: 40px 20px;
}

.form-success.show {
  display: block;
}

.form-success svg {
  margin-bottom: 16px;
}

.form-success h4 {
  font-size: 18px;
  font-weight: 600;
  color: var(--color-primary);
  margin-bottom: 8px;
}

.form-success p {
  font-size: 14px;
  color: var(--color-text-light);
}