/* ============================================================
   ChemB2B - SaaS系统页面样式 v4.0
   仪表盘预览 | 模块卡片 | 功能对比 | 定价 | FAQ | 响应式
   ============================================================ */

/* ========== Hero 大屏 ========== */
.sd-hero {
  position: relative; min-height: 92vh; display: flex; align-items: center;
  background: linear-gradient(160deg, #082f49 0%, #0c4a6e 30%, #075985 50%, #0e7490 70%, #0891b2 100%);
  overflow: hidden; padding: 90px 0 80px;
}
.sd-hero-bg {
  position: absolute; inset: 0; pointer-events: none;
  background:
    radial-gradient(ellipse at 15% 25%, rgba(6,182,212,.18) 0%, transparent 55%),
    radial-gradient(ellipse at 80% 70%, rgba(99,102,241,.12) 0%, transparent 55%),
    radial-gradient(ellipse at 50% 50%, rgba(14,165,233,.06) 0%, transparent 60%);
}
.sd-hero-bg::after {
  content: ''; position: absolute; bottom: 0; left: 0; right: 0; height: 140px;
  background: linear-gradient(to top, var(--bg), transparent);
}
.sd-hero-inner {
  position: relative; z-index: 2; display: grid; grid-template-columns: 1fr 1fr;
  gap: 48px; align-items: center;
}
.sd-hero-text { color: #fff; max-width: 600px; }
.sd-hero-badge {
  display: inline-flex; align-items: center; gap: 8px;
  padding: 7px 18px; border-radius: 50px;
  background: rgba(255,255,255,.12); backdrop-filter: blur(12px);
  font-size: .85rem; font-weight: 600; margin-bottom: 24px;
  border: 1px solid rgba(255,255,255,.15);
  animation: fadeInDown .6s ease-out;
}
.sd-hero-badge .live-dot {
  width: 8px; height: 8px; background: #4ade80; border-radius: 50%;
  box-shadow: 0 0 8px rgba(74,222,128,.6);
  animation: livePulse 2s ease-in-out infinite;
}
.sd-hero-text h1 {
  font-size: 3rem; font-weight: 900; line-height: 1.2; margin-bottom: 22px;
  letter-spacing: -1.5px; animation: fadeInUp .8s ease-out;
}
.sd-hero-text h1 span {
  background: linear-gradient(135deg, #22d3ee, #a5f3fc);
  -webkit-background-clip: text; -webkit-text-fill-color: transparent; background-clip: text;
}
.sd-hero-text p {
  font-size: 1.1rem; opacity: .9; line-height: 1.8; margin-bottom: 34px;
  animation: fadeInUp .8s ease-out .15s both;
}
.sd-hero-btns {
  display: flex; gap: 16px; flex-wrap: wrap; margin-bottom: 48px;
  animation: fadeInUp .8s ease-out .3s both;
}
.sd-hero-metrics {
  display: flex; gap: 36px; flex-wrap: wrap;
  animation: fadeInUp .8s ease-out .45s both;
}
.sd-hm-item { position: relative; }
.sd-hm-item:not(:last-child)::after {
  content: ''; position: absolute; right: -18px; top: 10%; height: 80%; width: 1px;
  background: rgba(255,255,255,.15);
}
.sd-hm-num {
  font-size: 1.8rem; font-weight: 900; color: #22d3ee; letter-spacing: -1px;
}
.sd-hm-label { font-size: .82rem; color: rgba(255,255,255,.65); margin-top: 4px; font-weight: 500; }

/* ---- 演示仪表盘 ---- */
.sd-demo-dashboard {
  background: rgba(255,255,255,.95);
  backdrop-filter: blur(24px); -webkit-backdrop-filter: blur(24px);
  border-radius: var(--radius-xl); overflow: hidden;
  box-shadow: 0 30px 60px rgba(0,0,0,.35);
  animation: scaleInUp .7s ease-out .5s both;
  border: 1px solid rgba(255,255,255,.3);
}
.sd-dd-header {
  display: flex; align-items: center; gap: 16px; padding: 16px 24px;
  background: #f8fafc; border-bottom: 1px solid var(--border-light);
}
.sd-dd-dots { display: flex; gap: 6px; }
.sd-dd-dots span {
  width: 10px; height: 10px; border-radius: 50%;
}
.sd-dd-dots span:nth-child(1) { background: #ef4444; }
.sd-dd-dots span:nth-child(2) { background: #f59e0b; }
.sd-dd-dots span:nth-child(3) { background: #10b981; }
.sd-dd-title { font-size: .88rem; font-weight: 700; color: var(--text); }
.sd-dd-live {
  font-size: .72rem; color: #ef4444; font-weight: 800;
  animation: badgePulse 2s ease-in-out infinite;
}
.sd-dd-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 1px; background: var(--border-light); }
.sd-dd-stat { padding: 18px 20px; background: #fff; transition: background var(--transition); }
.sd-dd-stat:hover { background: #f8fafc; }
.sd-dd-stat-top { display: flex; justify-content: space-between; align-items: center; font-size: .78rem; color: var(--text-secondary); margin-bottom: 6px; }
.sd-stat-up { color: #dc2626; font-weight: 700; font-size: .76rem; }
.sd-stat-down { color: #16a34a; font-weight: 700; font-size: .76rem; }
.sd-stat-warn { color: #f59e0b; font-weight: 700; font-size: .76rem; }
.sd-stat-num { font-size: 1.6rem; font-weight: 900; color: var(--text); transition: transform .15s; }
.sd-stat-sub { font-size: .72rem; color: var(--text-muted); margin-top: 2px; }
.sd-bounce { display: inline-block; animation: numberBounce .4s ease-out; animation-delay: var(--delay, 0s); }
.sd-dd-chart { padding: 20px 24px; }
.sd-dd-chart-label { font-size: .8rem; font-weight: 700; color: var(--text-secondary); margin-bottom: 14px; }
.sd-chart-bars { display: flex; align-items: flex-end; gap: 6px; height: 80px; }
.sd-chart-bar {
  flex: 1; border-radius: 4px 4px 0 0;
  background: linear-gradient(180deg, var(--primary-light), var(--primary));
  height: var(--h, 50%); animation: chartGrow .6s ease-out var(--d, 0s) both;
  min-height: 4px; opacity: .8;
}
@keyframes chartGrow {
  from { height: 0; opacity: 0; }
  to { height: var(--h, 50%); opacity: .8; }
}

/* ========== 侧边快捷导航 ========== */
.sd-quick-nav {
  position: fixed; right: 20px; top: 50%; transform: translateY(-50%);
  z-index: 900; display: flex; flex-direction: column; gap: 6px;
}
.sd-ql-toggle { display: none; }
.sd-quick-link {
  display: flex; align-items: center; gap: 8px; padding: 8px 14px; border-radius: 50px;
  font-size: .82rem; font-weight: 600; text-decoration: none; white-space: nowrap;
  background: rgba(255,255,255,.85); backdrop-filter: blur(12px);
  color: var(--text-secondary); border: 1px solid var(--border-light);
  box-shadow: var(--shadow-sm); transition: all var(--transition);
}
.sd-quick-link:hover { background: var(--primary); color: #fff; border-color: var(--primary); transform: translateX(-2px); }
.sd-quick-link.active { background: var(--primary-gradient); color: #fff; border-color: transparent; box-shadow: 0 4px 12px rgba(3,105,161,.35); }

/* ========== 模块卡片 ========== */
.sd-module-card {
  background: var(--white); border-radius: var(--radius-xl); padding: 30px 26px;
  border: 1px solid var(--border-light); cursor: pointer; position: relative;
  transition: all var(--transition); overflow: hidden; text-align: center;
  animation: fadeInUp .6s ease-out both;
  animation-delay: var(--delay, 0s);
}
.sd-module-card:hover {
  transform: translateY(-8px); box-shadow: var(--shadow-xl); border-color: var(--primary);
}
.sd-module-card:focus-visible {
  outline: 3px solid var(--primary); outline-offset: 2px;
}
.sd-module-card::before {
  content: ''; position: absolute; top: 0; left: 0; right: 0; height: 4px;
  background: var(--primary-gradient); transform: scaleX(0); transition: transform var(--transition);
}
.sd-module-card:hover::before { transform: scaleX(1); }
.sd-mc-badge {
  position: absolute; top: 12px; right: 14px;
  width: 32px; height: 32px; border-radius: 50%;
  color: #fff; font-size: .72rem; font-weight: 800;
  display: flex; align-items: center; justify-content: center;
  opacity: .7; transition: opacity var(--transition);
}
.sd-module-card:hover .sd-mc-badge { opacity: 1; }
.sd-mc-icon {
  width: 64px; height: 64px; margin: 0 auto 16px;
  border-radius: var(--radius-lg); display: flex; align-items: center; justify-content: center;
  font-size: 2rem; transition: all var(--transition);
}
.sd-module-card:hover .sd-mc-icon { transform: scale(1.1) rotate(-5deg); }
.sd-module-card h3 { font-size: 1.08rem; font-weight: 700; margin-bottom: 10px; color: var(--text); }
.sd-module-card p { font-size: .85rem; color: var(--text-secondary); line-height: 1.6; margin-bottom: 16px; }
.sd-mc-features { display: flex; flex-wrap: wrap; gap: 6px; justify-content: center; margin-bottom: 16px; }
.sd-mc-tag {
  padding: 3px 10px; border-radius: 50px; font-size: .74rem; font-weight: 500;
  background: var(--bg); color: var(--text-secondary);
  border: 1px solid var(--border-light); transition: all var(--transition);
}
.sd-module-card:hover .sd-mc-tag { background: var(--primary-bg); color: var(--primary); border-color: transparent; }
.sd-mc-more { background: var(--primary-bg) !important; color: var(--primary) !important; font-weight: 600; }
.sd-mc-action {
  font-size: .85rem; font-weight: 700; color: var(--primary);
  display: inline-flex; align-items: center; gap: 6px;
  transition: gap var(--transition);
}
.sd-mc-action span { transition: transform var(--transition); }
.sd-module-card:hover .sd-mc-action { gap: 10px; }
.sd-module-card:hover .sd-mc-action span { transform: translateX(3px); }

/* ========== Modal 系统 ========== */
.sd-modal-overlay {
  position: fixed; inset: 0; background: rgba(15,23,42,.65);
  backdrop-filter: blur(6px); -webkit-backdrop-filter: blur(6px);
  z-index: 2000; display: flex; align-items: center; justify-content: center;
  animation: fadeIn .2s ease-out; padding: 20px;
}
.sd-modal-content {
  background: var(--white); border-radius: var(--radius-xl);
  box-shadow: var(--shadow-xl); width: 100%; max-width: 620px;
  max-height: 85vh; overflow-y: auto; animation: scaleIn .3s ease-out;
}
.sd-modal-header {
  display: flex; align-items: center; gap: 16px; padding: 24px 28px;
  color: #fff; border-radius: var(--radius-xl) var(--radius-xl) 0 0;
  position: sticky; top: 0; z-index: 10;
}
.sd-modal-icon { font-size: 2.2rem; flex-shrink: 0; }
.sd-modal-header h2 { font-size: 1.2rem; font-weight: 800; margin-bottom: 4px; }
.sd-modal-header p { font-size: .85rem; opacity: .9; }
.sd-modal-close {
  width: 36px; height: 36px; border-radius: 50%; flex-shrink: 0;
  background: rgba(255,255,255,.2); color: #fff; font-size: 1.1rem;
  display: flex; align-items: center; justify-content: center;
  transition: all var(--transition); margin-left: auto; border: none; cursor: pointer;
}
.sd-modal-close:hover { background: rgba(255,255,255,.4); transform: rotate(90deg); }
.sd-modal-body { padding: 24px 28px 28px; }
.sd-modal-body h3 { font-size: 1rem; font-weight: 700; margin-bottom: 16px; }
.sd-modal-features { display: grid; grid-template-columns: 1fr 1fr; gap: 10px; margin-bottom: 24px; }
.sd-mf-item {
  display: flex; align-items: center; gap: 10px; padding: 10px 14px;
  background: var(--bg-alt); border-radius: var(--radius);
  font-size: .88rem; border: 1px solid var(--border-light);
}
.sd-mf-check {
  width: 22px; height: 22px; border-radius: 50%;
  background: var(--success); color: #fff; font-size: .7rem;
  display: flex; align-items: center; justify-content: center; flex-shrink: 0; font-weight: 700;
}
.sd-modal-actions { display: flex; gap: 12px; justify-content: flex-end; }

/* ========== 演示预约表单 ========== */
.sd-demo-modal .sd-modal-body { padding: 24px 28px 20px; }
.sd-checkbox-grid {
  display: grid; grid-template-columns: 1fr 1fr; gap: 8px;
}
.sd-checkbox-item {
  display: flex; align-items: center; gap: 8px; padding: 8px 12px;
  background: var(--bg-alt); border-radius: var(--radius);
  font-size: .84rem; cursor: pointer; transition: all var(--transition);
  border: 1px solid var(--border-light);
}
.sd-checkbox-item:hover { border-color: var(--primary); background: var(--primary-bg); }
.sd-checkbox-item input[type="checkbox"] { accent-color: var(--primary); width: 16px; height: 16px; }
.sd-form-footer { margin-top: 20px; }
.sd-submit-success { text-align: center; padding: 20px 0; }
.sd-success-icon { font-size: 4rem; margin-bottom: 16px; animation: scaleIn .5s ease-out; }
.sd-submit-success h3 { font-size: 1.3rem; font-weight: 800; margin-bottom: 10px; color: var(--text); }
.sd-submit-success p { font-size: .95rem; color: var(--text-secondary); line-height: 1.7; }

/* ========== 功能对比 ========== */
.sd-compare-section { background: var(--bg); padding: 80px 0; }
.sd-compare-tabs {
  display: flex; gap: 8px; justify-content: center; margin-bottom: 28px; flex-wrap: wrap;
}
.sd-compare-tab {
  padding: 10px 22px; border-radius: 50px; font-size: .88rem; font-weight: 600;
  background: var(--white); border: 1px solid var(--border); color: var(--text-secondary);
  cursor: pointer; transition: all var(--transition); font-family: inherit;
}
.sd-compare-tab:hover { border-color: var(--primary); color: var(--primary); }
.sd-compare-tab.active {
  background: var(--primary-gradient); color: #fff; border-color: transparent;
  box-shadow: 0 4px 12px rgba(3,105,161,.3);
}
.sd-compare-panel { display: none; }
.sd-compare-panel.active { display: block; }
.sd-compare-table {
  width: 100%; border-collapse: collapse; background: var(--white);
  border-radius: var(--radius-lg); overflow: hidden;
  box-shadow: var(--shadow); border: 1px solid var(--border-light);
}
.sd-compare-table th {
  padding: 16px 18px; background: var(--bg-alt); font-size: .84rem; font-weight: 700;
  color: var(--text); border-bottom: 2px solid var(--border); text-align: center;
}
.sd-compare-table th:first-child { text-align: left; min-width: 140px; }
.sd-ct-popular {
  background: linear-gradient(180deg, var(--primary-bg), #e0f2fe) !important;
  color: var(--primary) !important; position: relative;
}
.sd-ct-popular::after {
  content: '推荐'; position: absolute; top: -2px; left: 50%; transform: translateX(-50%);
  background: var(--primary-gradient); color: #fff; padding: 2px 12px;
  border-radius: 0 0 8px 8px; font-size: .66rem; font-weight: 700;
}
.sd-compare-table td {
  padding: 14px 18px; border-bottom: 1px solid var(--border-light);
  font-size: .88rem; color: var(--text-secondary); text-align: center;
}
.sd-compare-table td:first-child { text-align: left; font-weight: 600; color: var(--text); }
.sd-compare-table tr:hover td { background: var(--bg-alt); }
.sd-compare-table tr:last-child td { border-bottom: none; }

/* ========== 定价切换 ========== */
.sd-pricing-section { padding: 80px 0; }
.sd-pricing-toggle {
  display: flex; align-items: center; gap: 8px; justify-content: center; margin-bottom: 36px;
}
.sd-pricing-toggle > span { font-size: .9rem; color: var(--text-secondary); font-weight: 500; }
.sd-pt-toggle {
  padding: 10px 26px; border-radius: 50px; font-size: .88rem; font-weight: 600;
  background: var(--white); border: 1px solid var(--border); color: var(--text-secondary);
  cursor: pointer; transition: all var(--transition); font-family: inherit;
  display: inline-flex; align-items: center; gap: 8px;
}
.sd-pt-toggle:hover { border-color: var(--primary); color: var(--primary); }
.sd-pt-toggle.active {
  background: var(--primary-gradient); color: #fff; border-color: transparent;
  box-shadow: 0 4px 12px rgba(3,105,161,.3);
}
.sd-pt-save {
  padding: 2px 8px; border-radius: 50px; font-size: .7rem; font-weight: 700;
  background: rgba(239,68,68,.15); color: #dc2626;
}
.sd-pt-toggle.active .sd-pt-save { background: rgba(255,255,255,.25); color: #fff; }

/* 定价卡增强 */
.pricing-card { position: relative; overflow: hidden; }
.plan-icon { font-size: 2.6rem; margin-bottom: 8px; }
.plan-save {
  margin-top: 8px; padding: 4px 14px; border-radius: 50px;
  background: #fef2f2; color: #dc2626; font-size: .78rem; font-weight: 700;
  display: inline-block;
}

/* ========== 安全保障条 ========== */
.sd-security-strip {
  background: linear-gradient(135deg, #0c4a6e, #0369a1);
  padding: 40px 0; position: relative; overflow: hidden;
}
.sd-security-strip::before {
  content: ''; position: absolute; inset: 0;
  background: radial-gradient(circle at 20% 50%, rgba(6,182,212,.08), transparent 60%);
  pointer-events: none;
}
.sd-security-grid {
  display: grid; grid-template-columns: repeat(5, 1fr); gap: 16px; position: relative; z-index: 1;
}
.sd-sec-item {
  display: flex; align-items: center; gap: 12px;
  padding: 14px 18px; border-radius: var(--radius);
  background: rgba(255,255,255,.06); border: 1px solid rgba(255,255,255,.08);
  transition: all var(--transition);
}
.sd-sec-item:hover {
  background: rgba(255,255,255,.12); transform: translateY(-2px);
}
.sd-sec-icon { font-size: 1.6rem; flex-shrink: 0; }
.sd-sec-item strong { display: block; color: #fff; font-size: .9rem; font-weight: 700; }
.sd-sec-item span { display: block; color: rgba(255,255,255,.65); font-size: .76rem; margin-top: 2px; }

/* ========== 核心优势卡片 ========== */
.sd-benefit-card {
  background: var(--white); border-radius: var(--radius-xl); padding: 32px 26px;
  border: 1px solid var(--border-light); text-align: center;
  transition: all var(--transition); position: relative; overflow: hidden;
  animation: fadeInUp .6s ease-out both;
  animation-delay: var(--delay, 0s);
}
.sd-benefit-card:hover { transform: translateY(-6px); box-shadow: var(--shadow-xl); border-color: var(--primary); }
.sd-benefit-card::after {
  content: ''; position: absolute; bottom: 0; left: 20%; right: 20%; height: 3px;
  background: var(--primary-gradient); border-radius: 2px;
  transform: scaleX(0); transition: transform var(--transition);
}
.sd-benefit-card:hover::after { transform: scaleX(1); left: 0; right: 0; }
.sd-bc-icon { font-size: 2.6rem; margin-bottom: 16px; display: block; transition: transform var(--transition); }
.sd-benefit-card:hover .sd-bc-icon { transform: scale(1.1); }
.sd-benefit-card h3 { font-size: 1.1rem; font-weight: 700; margin-bottom: 10px; color: var(--text); }
.sd-benefit-card p { font-size: .85rem; color: var(--text-secondary); line-height: 1.8; }

/* ========== 客户品牌墙 ========== */
.sd-customers { background: var(--bg); }
.sd-logo-marquee { overflow: hidden; padding: 10px 0 30px; position: relative; }
.sd-logo-marquee::before,
.sd-logo-marquee::after {
  content: ''; position: absolute; top: 0; bottom: 0; width: 80px; z-index: 2; pointer-events: none;
}
.sd-logo-marquee::before { left: 0; background: linear-gradient(to right, var(--bg), transparent); }
.sd-logo-marquee::after { right: 0; background: linear-gradient(to left, var(--bg), transparent); }
.sd-logo-track {
  display: flex; gap: 24px; animation: marquee 35s linear infinite; width: max-content;
}
.sd-logo-item {
  display: flex; align-items: center; gap: 10px;
  padding: 16px 28px; border-radius: var(--radius);
  background: var(--white); box-shadow: var(--shadow-sm);
  font-weight: 700; color: var(--text); white-space: nowrap;
  border: 1px solid var(--border-light); font-size: .95rem;
  transition: all var(--transition);
}
.sd-logo-item:hover { box-shadow: var(--shadow); transform: translateY(-2px); border-color: var(--primary); }

/* ========== FAQ 区 ========== */
.sd-faq-search { max-width: 520px; margin: 0 auto 28px; }
.sd-faq-search .form-input { padding-left: 48px; }
.sd-faq-list { max-width: 800px; margin: 0 auto; display: flex; flex-direction: column; gap: 12px; }
.sd-faq-item {
  background: var(--white); border-radius: var(--radius-lg);
  border: 1px solid var(--border-light); overflow: hidden;
  transition: all var(--transition); box-shadow: var(--shadow-sm);
}
.sd-faq-item:hover { border-color: var(--primary); }
.sd-faq-header {
  display: flex; align-items: center; gap: 14px;
  padding: 18px 24px; cursor: pointer; user-select: none;
  transition: background var(--transition);
}
.sd-faq-header:hover { background: var(--bg-alt); }
.sd-faq-icon { font-size: 1.3rem; flex-shrink: 0; }
.sd-faq-q { flex: 1; font-size: .95rem; font-weight: 600; color: var(--text); line-height: 1.5; }
.sd-faq-arrow {
  font-size: .9rem; color: var(--text-muted); transition: transform var(--transition);
  flex-shrink: 0;
}
.sd-faq-item.active .sd-faq-arrow { transform: rotate(180deg); color: var(--primary); }
.sd-faq-item.active { border-color: var(--primary); box-shadow: 0 0 0 3px rgba(3,105,161,.06); }
.sd-faq-body {
  max-height: 0; overflow: hidden; transition: max-height .4s ease-out, padding .4s ease-out;
}
.sd-faq-item.active .sd-faq-body { max-height: 300px; }
.sd-faq-body p {
  padding: 0 24px 18px 64px; font-size: .88rem; color: var(--text-secondary); line-height: 1.8;
}

/* ========== CTA 区域增强 ========== */
.cta-section {
  background: linear-gradient(135deg, #082f49, var(--primary-dark), var(--primary));
  padding: 90px 0; text-align: center; color: #fff; position: relative; overflow: hidden;
}
.cta-section::before {
  content: ''; position: absolute; inset: 0;
  background: radial-gradient(circle at 30% 50%, rgba(6,182,212,.15), transparent 60%),
              radial-gradient(circle at 70% 30%, rgba(99,102,241,.1), transparent 60%);
}
.cta-section .container { position: relative; z-index: 1; }
.cta-section h2 { font-size: 2.2rem; font-weight: 900; margin-bottom: 14px; letter-spacing: -0.5px; }
.cta-section p { font-size: 1.1rem; opacity: .88; margin-bottom: 32px; max-width: 600px; margin-left: auto; margin-right: auto; }

/* ========== 响应式 ========== */
@media (max-width: 1200px) {
  .sd-security-grid { grid-template-columns: repeat(3, 1fr); }
}

@media (max-width: 1024px) {
  .sd-hero-inner { grid-template-columns: 1fr; gap: 40px; }
  .sd-hero-text { max-width: 100%; text-align: center; }
  .sd-hero-btns { justify-content: center; }
  .sd-hero-metrics { justify-content: center; }
  .sd-demo-dashboard { max-width: 560px; margin: 0 auto; }
  .sd-hero-text h1 { font-size: 2.3rem; }
  .sd-sec-item { flex-direction: column; text-align: center; gap: 6px; }
  .sd-quick-nav { right: 10px; }
}

@media (max-width: 768px) {
  .sd-hero { min-height: auto; padding: 70px 0 50px; }
  .sd-hero-text h1 { font-size: 1.8rem; }
  .sd-hero-text p { font-size: .92rem; }
  .sd-hero-metrics { gap: 20px; }
  .sd-hm-item:not(:last-child)::after { right: -10px; }
  .sd-hm-num { font-size: 1.4rem; }
  .sd-compare-table { font-size: .78rem; }
  .sd-compare-table th, .sd-compare-table td { padding: 10px 12px; }
  .sd-compare-tabs { flex-wrap: nowrap; overflow-x: auto; padding-bottom: 8px; justify-content: flex-start; -webkit-overflow-scrolling: touch; }
  .sd-compare-tab { white-space: nowrap; flex-shrink: 0; }
  .sd-security-grid { grid-template-columns: repeat(3, 1fr); gap: 10px; }
  .sd-sec-item { padding: 12px 10px; }
  .sd-quick-nav {
    position: fixed; right: 0; top: auto; bottom: 80px;
    transform: none; z-index: 950;
  }
  .sd-ql-toggle {
    display: flex; flex-direction: column; gap: 5px;
    width: 44px; height: 44px; border-radius: 50%;
    background: var(--primary-gradient); color: #fff;
    align-items: center; justify-content: center;
    box-shadow: var(--shadow-lg); border: none;
    position: relative; z-index: 2; cursor: pointer;
  }
  .sd-ql-toggle span {
    width: 18px; height: 2px; background: #fff;
    border-radius: 2px; transition: all var(--transition);
  }
  .sd-ql-toggle.active span:nth-child(1) { transform: rotate(45deg) translate(5px,5px); }
  .sd-ql-toggle.active span:nth-child(2) { opacity: 0; }
  .sd-ql-toggle.active span:nth-child(3) { transform: rotate(-45deg) translate(5px,-5px); }
  .sd-ql-list {
    position: absolute; bottom: 50px; right: 0;
    background: var(--white); border-radius: var(--radius-lg);
    box-shadow: var(--shadow-xl); padding: 8px; min-width: 140px;
    opacity: 0; visibility: hidden; transform: translateY(10px);
    transition: all var(--transition);
    display: flex; flex-direction: column; gap: 2px; list-style: none;
  }
  .sd-ql-list.open { opacity: 1; visibility: visible; transform: translateY(0); }
  .sd-quick-link { border-radius: var(--radius); box-shadow: none; font-size: .82rem; padding: 10px 14px; border: none; }
  .sd-quick-link:hover, .sd-quick-link.active { transform: none; }
  .sd-modal-features { grid-template-columns: 1fr; }
  .sd-checkbox-grid { grid-template-columns: 1fr 1fr; }
  .sd-dd-grid { grid-template-columns: 1fr 1fr; }
  .sd-demo-dashboard { max-width: 100%; }
  .sd-faq-body p { padding: 0 20px 16px 52px; }
  .sd-faq-header { padding: 14px 18px; }
  .sd-faq-q { font-size: .88rem; }
  .cta-section h2 { font-size: 1.6rem; }
  .pricing-card.popular { transform: none; }
  .pricing-card.popular:hover { transform: translateY(-4px); }
}

@media (max-width: 480px) {
  .sd-hero { padding: 56px 0 40px; }
  .sd-hero-text h1 { font-size: 1.45rem; }
  .sd-hero-text p { font-size: .85rem; }
  .sd-hero-btns { flex-direction: column; gap: 12px; }
  .sd-hero-btns .btn { width: 100%; }
  .sd-hero-metrics { display: grid; grid-template-columns: 1fr 1fr; gap: 16px; }
  .sd-hm-item::after { display: none !important; }
  .sd-module-card { padding: 22px 16px; }
  .sd-mc-icon { width: 50px; height: 50px; font-size: 1.6rem; }
  .sd-module-card h3 { font-size: .95rem; }
  .sd-mc-tag { font-size: .7rem; }
  .sd-dd-grid { grid-template-columns: 1fr; }
  .sd-dd-stat { padding: 12px 16px; }
  .sd-stat-num { font-size: 1.3rem; }
  .sd-chart-bars { height: 60px; }
  .sd-security-grid { grid-template-columns: repeat(2, 1fr); gap: 8px; }
  .sd-sec-item { padding: 10px 8px; }
  .sd-sec-icon { font-size: 1.2rem; }
  .sd-sec-item strong { font-size: .78rem; }
  .sd-sec-item span { font-size: .68rem; }
  .sd-benefit-card { padding: 24px 18px; }
  .sd-modal-content { max-width: 96vw; margin: 0 8px; }
  .sd-modal-header { padding: 18px 16px; flex-wrap: wrap; }
  .sd-modal-body { padding: 16px 16px 20px; }
  .sd-modal-features { grid-template-columns: 1fr; }
  .sd-checkbox-grid { grid-template-columns: 1fr; }
  .sd-compare-table { font-size: .72rem; }
  .sd-compare-table th, .sd-compare-table td { padding: 8px 6px; }
  .sd-compare-table th:first-child { min-width: 90px; }
  .sd-logo-item { padding: 12px 16px; font-size: .82rem; }
  .sd-faq-header { padding: 12px 14px; gap: 10px; }
  .sd-faq-icon { font-size: 1rem; }
  .sd-faq-q { font-size: .84rem; }
  .sd-faq-body p { padding: 0 14px 14px 40px; font-size: .82rem; }
  .cta-section { padding: 60px 0; }
  .cta-section h2 { font-size: 1.3rem; }
  .cta-section p { font-size: .9rem; }
  .sd-quick-nav { right: 4px; bottom: 70px; }
  .sd-ql-toggle { width: 38px; height: 38px; }
}

/* ========== 减少动画偏好 ========== */
@media (prefers-reduced-motion: reduce) {
  .sd-module-card, .sd-benefit-card { animation: none !important; }
  .sd-chart-bar { animation: none !important; height: var(--h) !important; }
  .sd-logo-track { animation-duration: 60s !important; }
}