:root {
  --primary: #4338ca;
  --primary-light: #6366f1;
  --secondary: #06b6d4;
  --accent: #f59e0b;
  --rose: #f43f5e;
  --emerald: #10b981;
  --text-main: #1e293b;
  --text-muted: #64748b;
  --bg-page: #f8fafc;
  --bg-card: #ffffff;
  --border-light: #e2e8f0;
  --shadow-sm: 0 2px 4px rgba(0,0,0,0.04);
  --shadow-md: 0 10px 25px -5px rgba(0,0,0,0.06), 0 8px 10px -6px rgba(0,0,0,0.04);
  --shadow-lg: 0 20px 30px -10px rgba(67, 56, 202, 0.12);
  --radius-sm: 8px;
  --radius-md: 14px;
  --radius-lg: 20px;
}

* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  scroll-behavior: smooth;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  background-color: var(--bg-page);
  color: var(--text-main);
  line-height: 1.6;
}

body {
  background: linear-gradient(180deg, #f0fdf4 0%, #eff6ff 15%, #faf5ff 40%, #fff7ed 70%, #f8fafc 100%);
  min-height: 100vh;
  position: relative;
  overflow-x: hidden;
}

.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 20px;
}

/* 斑斓氛围装饰条与微渐变 */
.rainbow-strip {
  height: 4px;
  background: linear-gradient(90deg, #ec4899, #8b5cf6, #3b82f6, #10b981, #f59e0b);
  width: 100%;
}

/* 顶部导航 */
header.site-header {
  position: sticky;
  top: 0;
  z-index: 1000;
  background: rgba(255, 255, 255, 0.92);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid rgba(226, 232, 240, 0.8);
  box-shadow: 0 2px 10px rgba(0,0,0,0.03);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 72px;
}

.brand-box {
  display: flex;
  align-items: center;
  gap: 12px;
}

.brand-box .ai-page-logo {
  height: 40px;
  width: auto;
  display: block;
}

.brand-text {
  font-size: 1.25rem;
  font-weight: 800;
  background: linear-gradient(135deg, #1e1b4b, #4338ca 60%, #06b6d4);
  -webkit-background-clip: text;
  color: #1e1b4b;
}

nav.main-nav {
  display: flex;
  align-items: center;
}

.nav-links {
  display: flex;
  list-style: none;
  gap: 0;
  align-items: center;
}

.nav-links li a {
  display: inline-block;
  padding: 8px 14px;
  color: #334155;
  text-decoration: none;
  font-size: 0.95rem;
  font-weight: 500;
  border-radius: var(--radius-sm);
  transition: all 0.25s ease;
}

.nav-links li a:hover,
.nav-links li a.active {
  color: var(--primary);
  background: rgba(99, 102, 241, 0.08);
}

.nav-btn-group {
  display: flex;
  align-items: center;
  gap: 10px;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  font-size: 0.95rem;
  font-weight: 600;
  padding: 10px 22px;
  border-radius: 50px;
  text-decoration: none;
  transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  cursor: pointer;
  border: 1px solid transparent;
  line-height: 1.2;
}

.btn-primary {
  background: linear-gradient(135deg, #4f46e5 0%, #7c3aed 100%);
  color: #ffffff;
  box-shadow: 0 4px 14px rgba(79, 70, 229, 0.35);
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 6px 20px rgba(79, 70, 229, 0.45);
}

.btn-rainbow {
  background: linear-gradient(135deg, #f43f5e 0%, #ec4899 30%, #8b5cf6 70%, #3b82f6 100%);
  color: #ffffff;
  box-shadow: 0 4px 16px rgba(236, 72, 153, 0.35);
}

.btn-rainbow:hover {
  transform: translateY(-2px);
  filter: brightness(1.08);
  box-shadow: 0 8px 24px rgba(236, 72, 153, 0.45);
}

.btn-outline {
  border-color: #cbd5e1;
  background: #ffffff;
  color: #334155;
}

.btn-outline:hover {
  border-color: var(--primary);
  color: var(--primary);
  background: #f8fafc;
}

.mobile-menu-btn {
  display: none;
  background: none;
  border: none;
  font-size: 1.5rem;
  color: var(--text-main);
  cursor: pointer;
}

/* 斑斓色彩标签与徽章 */
.badge-rainbow {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 6px 14px;
  background: #f1f5f9;
  border: 1px solid #e2e8f0;
  border-radius: 30px;
  font-size: 0.85rem;
  font-weight: 600;
  color: #334155;
}

.badge-rainbow span.dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: #10b981;
  box-shadow: 0 0 8px #10b981;
}

/* Hero 首屏 - 纯代码几何科技质感，不含任何图片 */
.hero-section {
  padding: 70px 0 60px;
  position: relative;
  text-align: center;
}

.hero-backdrop {
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  width: 90%;
  max-width: 900px;
  height: 380px;
  background: radial-gradient(circle at 30% 30%, rgba(244, 63, 94, 0.12), transparent 50%),
              radial-gradient(circle at 70% 60%, rgba(59, 130, 246, 0.15), transparent 50%),
              radial-gradient(circle at 50% 80%, rgba(16, 185, 129, 0.12), transparent 60%);
  filter: blur(40px);
  z-index: 0;
  pointer-events: none;
}

.hero-content {
  position: relative;
  z-index: 1;
  max-width: 920px;
  margin: 0 auto;
}

.hero-title {
  font-size: clamp(2rem, 4vw, 3.2rem);
  font-weight: 900;
  line-height: 1.25;
  letter-spacing: -0.02em;
  margin: 20px 0 18px;
  color: #0f172a;
}

.hero-title .highlight {
  background: linear-gradient(120deg, #4f46e5 0%, #ec4899 50%, #f59e0b 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.hero-lead {
  font-size: 1.15rem;
  color: #475569;
  max-width: 760px;
  margin: 0 auto 32px;
  line-height: 1.7;
}

.hero-actions {
  display: flex;
  justify-content: center;
  align-items: center;
  flex-wrap: wrap;
  gap: 16px;
  margin-bottom: 40px;
}

.hero-stats-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 16px;
  margin-top: 20px;
}

.stat-item {
  background: rgba(255, 255, 255, 0.85);
  border: 1px solid rgba(226, 232, 240, 0.8);
  border-radius: var(--radius-md);
  padding: 18px 14px;
  box-shadow: var(--shadow-sm);
  transition: transform 0.25s ease;
}

.stat-item:hover {
  transform: translateY(-3px);
  box-shadow: var(--shadow-md);
}

.stat-num {
  font-size: 1.8rem;
  font-weight: 800;
  color: #1e1b4b;
  line-height: 1.1;
  margin-bottom: 4px;
}

.stat-label {
  font-size: 0.85rem;
  color: var(--text-muted);
}

/* 区域通用规范 */
section.page-block {
  padding: 60px 0;
  position: relative;
}

.section-head {
  text-align: center;
  max-width: 720px;
  margin: 0 auto 44px;
}

.section-tag {
  display: inline-block;
  font-size: 0.8rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  padding: 4px 12px;
  border-radius: 20px;
  margin-bottom: 10px;
  background: rgba(79, 70, 229, 0.1);
  color: var(--primary);
}

.section-tag.tag-pink { background: rgba(244, 63, 94, 0.1); color: #e11d48; }
.section-tag.tag-cyan { background: rgba(6, 182, 212, 0.1); color: #0891b2; }
.section-tag.tag-amber { background: rgba(245, 158, 11, 0.1); color: #d97706; }
.section-tag.tag-green { background: rgba(16, 185, 129, 0.1); color: #059669; }

.section-title {
  font-size: 2rem;
  font-weight: 800;
  color: #0f172a;
  margin-bottom: 12px;
}

.section-subtitle {
  font-size: 1rem;
  color: #64748b;
  line-height: 1.6;
}

/* 聚合模型展区 */
.model-tags-container {
  background: #ffffff;
  border: 1px solid #e2e8f0;
  border-radius: var(--radius-lg);
  padding: 30px;
  box-shadow: var(--shadow-sm);
}

.model-pill-grid {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  justify-content: center;
  margin-bottom: 24px;
}

.model-pill {
  background: #f8fafc;
  border: 1px solid #e2e8f0;
  padding: 8px 16px;
  border-radius: 30px;
  font-size: 0.9rem;
  font-weight: 600;
  color: #334155;
  transition: all 0.25s ease;
}

.model-pill:hover {
  background: linear-gradient(135deg, #4f46e5, #06b6d4);
  color: #ffffff;
  border-color: transparent;
  transform: translateY(-2px);
  box-shadow: 0 4px 10px rgba(79, 70, 229, 0.2);
}

/* 网格卡片与服务阵列 */
.cards-grid-3 {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(340px, 1fr));
  gap: 24px;
}

.service-card {
  background: #ffffff;
  border-radius: var(--radius-md);
  border: 1px solid #f1f5f9;
  padding: 28px;
  box-shadow: var(--shadow-sm);
  transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  display: flex;
  flex-direction: column;
  position: relative;
  overflow: hidden;
}

.service-card::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 4px;
  background: linear-gradient(90deg, #4f46e5, #06b6d4);
  opacity: 0;
  transition: opacity 0.3s ease;
}

.service-card:hover {
  transform: translateY(-5px);
  box-shadow: var(--shadow-md);
  border-color: #cbd5e1;
}

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

.service-card.card-pink:hover::before { background: linear-gradient(90deg, #f43f5e, #ec4899); }
.service-card.card-amber:hover::before { background: linear-gradient(90deg, #f59e0b, #eab308); }
.service-card.card-emerald:hover::before { background: linear-gradient(90deg, #10b981, #14b8a6); }

.card-icon {
  width: 52px;
  height: 52px;
  border-radius: 14px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.4rem;
  font-weight: bold;
  margin-bottom: 20px;
  background: rgba(99, 102, 241, 0.1);
  color: var(--primary);
}

.card-title {
  font-size: 1.25rem;
  font-weight: 700;
  color: #0f172a;
  margin-bottom: 10px;
}

.card-desc {
  font-size: 0.95rem;
  color: #475569;
  line-height: 1.6;
  margin-bottom: 16px;
  flex-grow: 1;
}

.card-footer-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
}

.mini-tag {
  font-size: 0.75rem;
  padding: 2px 8px;
  background: #f1f5f9;
  color: #475569;
  border-radius: 4px;
  font-weight: 500;
}

/* 图文与素材展示区 */
.media-showcase-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
  gap: 24px;
  margin-top: 30px;
}

.media-card {
  background: #ffffff;
  border-radius: var(--radius-md);
  overflow: hidden;
  border: 1px solid #e2e8f0;
  box-shadow: var(--shadow-sm);
  transition: all 0.3s ease;
}

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

.media-card .img-wrapper {
  width: 100%;
  aspect-ratio: 16 / 9;
  background: #f1f5f9;
  overflow: hidden;
  position: relative;
}

.media-card .img-wrapper.square-ratio {
  aspect-ratio: 1 / 1;
}

.media-card img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
  transition: transform 0.4s ease;
}

.media-card:hover img {
  transform: scale(1.03);
}

.media-card-body {
  padding: 20px;
}

.media-card-title {
  font-size: 1.1rem;
  font-weight: 700;
  color: #1e293b;
  margin-bottom: 6px;
}

.media-card-text {
  font-size: 0.88rem;
  color: #64748b;
  line-height: 1.5;
}

/* 流程步骤 */
.steps-wrapper {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 20px;
}

.step-card {
  background: #ffffff;
  border: 1px solid #e2e8f0;
  border-radius: var(--radius-md);
  padding: 24px;
  position: relative;
}

.step-badge {
  display: inline-block;
  font-size: 0.8rem;
  font-weight: 800;
  padding: 3px 10px;
  background: #eff6ff;
  color: #2563eb;
  border-radius: 6px;
  margin-bottom: 12px;
}

.step-title {
  font-size: 1.1rem;
  font-weight: 700;
  color: #0f172a;
  margin-bottom: 8px;
}

.step-desc {
  font-size: 0.9rem;
  color: #64748b;
  line-height: 1.5;
}

/* 对比评测表格与卡片 */
.review-highlight-card {
  background: linear-gradient(135deg, #1e1b4b 0%, #312e81 100%);
  color: #ffffff;
  border-radius: var(--radius-lg);
  padding: 36px;
  margin-bottom: 30px;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
}

.review-score-box {
  display: flex;
  align-items: baseline;
  gap: 12px;
}

.review-score-big {
  font-size: 3.8rem;
  font-weight: 900;
  color: #38bdf8;
  line-height: 1;
}

.review-score-base {
  font-size: 1.4rem;
  color: #cbd5e1;
}

.review-stars {
  color: #facc15;
  font-size: 1.3rem;
  letter-spacing: 2px;
  margin-top: 4px;
}

.table-responsive {
  width: 100%;
  overflow-x: auto;
  background: #ffffff;
  border-radius: var(--radius-md);
  border: 1px solid #e2e8f0;
  box-shadow: var(--shadow-sm);
}

.comparison-table {
  width: 100%;
  border-collapse: collapse;
  text-align: left;
  font-size: 0.95rem;
}

.comparison-table th,
.comparison-table td {
  padding: 16px 20px;
  border-bottom: 1px solid #f1f5f9;
}

.comparison-table th {
  background: #f8fafc;
  font-weight: 700;
  color: #1e293b;
}

.comparison-table tr:hover td {
  background: #fafafa;
}

.comparison-table td.highlight-col {
  background: rgba(238, 242, 255, 0.5);
  font-weight: 600;
  color: var(--primary);
}

.tag-badge-green {
  display: inline-block;
  padding: 2px 8px;
  background: #ecfdf5;
  color: #059669;
  border-radius: 4px;
  font-size: 0.8rem;
  font-weight: 600;
}

/* 用户评论卡片 */
.reviews-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
  gap: 24px;
}

.review-card {
  background: #ffffff;
  border-radius: var(--radius-md);
  border: 1px solid #e2e8f0;
  padding: 26px;
  box-shadow: var(--shadow-sm);
  display: flex;
  flex-direction: column;
  justify-content: space-between;
}

.review-quote {
  font-size: 0.95rem;
  color: #334155;
  line-height: 1.6;
  margin-bottom: 20px;
  position: relative;
}

.review-user-info {
  display: flex;
  align-items: center;
  gap: 12px;
  border-top: 1px solid #f1f5f9;
  padding-top: 14px;
}

.user-avatar-badge {
  width: 44px;
  height: 44px;
  border-radius: 50%;
  background: linear-gradient(135deg, #6366f1, #06b6d4);
  color: #ffffff;
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 800;
  font-size: 1rem;
}

.user-name {
  font-weight: 700;
  font-size: 0.95rem;
  color: #0f172a;
}

.user-role {
  font-size: 0.8rem;
  color: #64748b;
}

/* FAQ 折叠面板 */
.faq-list {
  display: flex;
  flex-direction: column;
  gap: 14px;
  max-width: 900px;
  margin: 0 auto;
}

.faq-item {
  background: #ffffff;
  border: 1px solid #e2e8f0;
  border-radius: var(--radius-md);
  overflow: hidden;
  transition: border-color 0.25s ease;
}

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

.faq-question {
  padding: 20px 24px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  cursor: pointer;
  font-weight: 700;
  font-size: 1.02rem;
  color: #1e293b;
  user-select: none;
}

.faq-toggle-icon {
  font-size: 1.2rem;
  color: #94a3b8;
  transition: transform 0.3s ease;
}

.faq-item.active .faq-toggle-icon {
  transform: rotate(45deg);
  color: var(--primary);
}

.faq-answer {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.35s ease, padding 0.35s ease;
  background: #f8fafc;
  color: #475569;
  font-size: 0.95rem;
  line-height: 1.65;
  padding: 0 24px;
}

.faq-item.active .faq-answer {
  padding: 16px 24px 22px;
  max-height: 300px;
  border-top: 1px solid #f1f5f9;
}

/* 文章资讯列表 */
.articles-section-box {
  background: #ffffff;
  border-radius: var(--radius-lg);
  border: 1px solid #e2e8f0;
  padding: 36px;
  box-shadow: var(--shadow-sm);
}

.article-dynamic-container {
  margin-bottom: 24px;
  padding: 16px 20px;
  background: #f8fafc;
  border-left: 4px solid var(--primary);
  border-radius: 4px;
  font-size: 0.95rem;
  color: #334155;
}

.article-links-list {
  list-style: none;
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 14px;
}

.article-links-list li a {
  display: block;
  padding: 12px 16px;
  background: #f8fafc;
  border: 1px solid #e2e8f0;
  border-radius: var(--radius-sm);
  color: #334155;
  text-decoration: none;
  font-size: 0.9rem;
  transition: all 0.2s ease;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.article-links-list li a:hover {
  background: #eff6ff;
  border-color: #93c5fd;
  color: #1d4ed8;
}

/* 表单与联系模块 */
.contact-grid {
  display: grid;
  grid-template-columns: 1fr 1.2fr;
  gap: 36px;
  background: #ffffff;
  border-radius: var(--radius-lg);
  border: 1px solid #e2e8f0;
  padding: 40px;
  box-shadow: var(--shadow-md);
}

.contact-info {
  display: flex;
  flex-direction: column;
  justify-content: space-between;
}

.contact-info-title {
  font-size: 1.5rem;
  font-weight: 800;
  color: #0f172a;
  margin-bottom: 12px;
}

.contact-info-desc {
  font-size: 0.95rem;
  color: #64748b;
  margin-bottom: 24px;
  line-height: 1.6;
}

.qr-box {
  background: #f8fafc;
  border: 1px solid #e2e8f0;
  border-radius: var(--radius-md);
  padding: 16px;
  display: inline-flex;
  flex-direction: column;
  align-items: center;
  width: fit-content;
  margin-bottom: 20px;
}

.qr-box img {
  width: 130px;
  height: 130px;
  display: block;
  border-radius: 8px;
}

.qr-label {
  margin-top: 8px;
  font-size: 0.8rem;
  font-weight: 600;
  color: #475569;
}

.contact-details-list {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 10px;
  font-size: 0.95rem;
  color: #334155;
}

.contact-details-list strong {
  color: #0f172a;
}

/* 现代化表单 */
.form-group {
  margin-bottom: 18px;
}

.form-label {
  display: block;
  font-size: 0.9rem;
  font-weight: 600;
  color: #334155;
  margin-bottom: 6px;
}

.form-control {
  width: 100%;
  padding: 12px 16px;
  font-size: 0.95rem;
  border: 1px solid #cbd5e1;
  border-radius: var(--radius-sm);
  background: #ffffff;
  color: #1e293b;
  outline: none;
  transition: border-color 0.25s ease, box-shadow 0.25s ease;
}

.form-control:focus {
  border-color: var(--primary-light);
  box-shadow: 0 0 0 3px rgba(99, 102, 241, 0.15);
}

textarea.form-control {
  resize: vertical;
  min-height: 110px;
}

/* Banner 宣传条图文区 */
.banner-gallery-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
  gap: 20px;
  margin-top: 20px;
}

.banner-gallery-item {
  border-radius: var(--radius-md);
  overflow: hidden;
  border: 1px solid #e2e8f0;
  box-shadow: var(--shadow-sm);
}

.banner-gallery-item img.ai-page-image {
  width: 100%;
  height: 220px;
  object-fit: cover;
  display: block;
  transition: transform 0.3s ease;
}

.banner-gallery-item:hover img.ai-page-image {
  transform: scale(1.02);
}

/* 友情链接与页脚 */
.friend-links-box {
  padding: 30px;
  background: #ffffff;
  border-radius: var(--radius-md);
  border: 1px solid #e2e8f0;
  margin-bottom: 40px;
}

.friend-links-title {
  font-size: 1rem;
  font-weight: 700;
  color: #1e293b;
  margin-bottom: 14px;
}

.friend-links-items {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

.friend-links-items a {
  color: #475569;
  text-decoration: none;
  font-size: 0.9rem;
  padding: 4px 12px;
  background: #f8fafc;
  border-radius: 4px;
  border: 1px solid #e2e8f0;
  transition: all 0.2s ease;
}

.friend-links-items a:hover {
  color: var(--primary);
  border-color: var(--primary-light);
  background: #eff6ff;
}

footer.site-footer {
  background: #0f172a;
  color: #94a3b8;
  padding: 50px 0 30px;
  border-top: 1px solid #1e293b;
}

.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr;
  gap: 40px;
  margin-bottom: 40px;
}

.footer-brand-title {
  font-size: 1.25rem;
  font-weight: 800;
  color: #ffffff;
  margin-bottom: 12px;
}

.footer-brand-desc {
  font-size: 0.9rem;
  line-height: 1.6;
  max-width: 400px;
}

.footer-col-title {
  font-size: 1rem;
  font-weight: 700;
  color: #ffffff;
  margin-bottom: 16px;
}

.footer-links-list {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.footer-links-list a {
  color: #94a3b8;
  text-decoration: none;
  font-size: 0.9rem;
  transition: color 0.2s ease;
}

.footer-links-list a:hover {
  color: #38bdf8;
}

.footer-bottom {
  border-top: 1px solid #1e293b;
  padding-top: 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 16px;
  font-size: 0.85rem;
}

.footer-bottom a {
  color: #94a3b8;
  text-decoration: none;
}

/* 浮动客服挂件 */
.floating-widget {
  position: fixed;
  right: 20px;
  bottom: 30px;
  z-index: 999;
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.float-btn {
  width: 50px;
  height: 50px;
  border-radius: 50%;
  background: #ffffff;
  box-shadow: 0 6px 16px rgba(0,0,0,0.15);
  display: flex;
  align-items: center;
  justify-content: center;
  color: #1e293b;
  text-decoration: none;
  font-size: 1.2rem;
  border: 1px solid #e2e8f0;
  transition: transform 0.25s ease, background-color 0.25s ease;
  cursor: pointer;
}

.float-btn:hover {
  transform: scale(1.1);
  background: #f8fafc;
  color: var(--primary);
}

.float-btn.btn-top {
  display: none;
  background: var(--primary);
  color: #ffffff;
  border-color: var(--primary);
}

/* 响应式断点控制 */
@media (max-width: 992px) {
  .hero-stats-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  .contact-grid {
    grid-template-columns: 1fr;
  }
  .footer-grid {
    grid-template-columns: 1fr;
    gap: 30px;
  }
}

@media (max-width: 768px) {
  .mobile-menu-btn {
    display: block;
  }
  nav.main-nav {
    display: none;
    position: absolute;
    top: 72px;
    left: 0;
    width: 100%;
    background: #ffffff;
    border-bottom: 1px solid #e2e8f0;
    box-shadow: var(--shadow-md);
    padding: 20px;
  }
  nav.main-nav.show {
    display: block;
  }
  .nav-links {
    flex-direction: column;
    align-items: stretch;
    gap: 0;
  }
  .nav-links li a {
    padding: 12px 16px;
    border-radius: 6px;
  }
  .nav-btn-group {
    display: none;
  }
  .cards-grid-3 {
    grid-template-columns: 1fr;
  }
  .hero-section {
    padding: 40px 0;
  }
  .hero-title {
    font-size: 1.8rem;
  }
}