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

:root {
  --primary: #4f6ef7;
  --primary-dark: #3a55e0;
  --dark: #141a2e;
  --gray: #6b7280;
  --light: #f6f8ff;
  --radius: 14px;
}

html {
  scroll-behavior: smooth;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, 'PingFang SC', 'Microsoft YaHei', 'Helvetica Neue', Arial, sans-serif;
  color: #1f2937;
  line-height: 1.7;
  background: #fff;
}

a {
  text-decoration: none;
  color: inherit;
}

.container {
  max-width: 1160px;
  margin: 0 auto;
  padding: 0 24px;
}

/* ========== 按钮 ========== */
.btn {
  display: inline-block;
  padding: 10px 24px;
  border-radius: 999px;
  font-size: 15px;
  font-weight: 600;
  transition: all 0.25s;
  cursor: pointer;
  border: 1px solid transparent;
}

.btn-primary {
  background: var(--primary);
  color: #fff;
}

.btn-primary:hover {
  background: var(--primary-dark);
  transform: translateY(-2px);
  box-shadow: 0 8px 20px rgba(79, 110, 247, 0.35);
}

.btn-ghost {
  border-color: #d3d9e8;
  color: var(--dark);
}

.btn-ghost:hover {
  border-color: var(--primary);
  color: var(--primary);
}

.btn-lg {
  padding: 14px 36px;
  font-size: 16px;
}

.btn-block {
  display: block;
  text-align: center;
}

.btn-light {
  background: #fff;
  color: var(--primary);
}

.btn-light:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 20px rgba(255, 255, 255, 0.3);
}

/* ========== 导航 ========== */
.nav {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(255, 255, 255, 0.85);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid #eef1f8;
}

.nav-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 68px;
}

.logo {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 20px;
  font-weight: 700;
  color: var(--dark);
}

.logo-icon {
  font-size: 24px;
}

.menu {
  display: flex;
  gap: 32px;
}

.menu a {
  font-size: 15px;
  color: var(--gray);
  transition: color 0.2s;
}

.menu a:hover {
  color: var(--primary);
}

.nav-actions {
  display: flex;
  gap: 12px;
  align-items: center;
}

.nav-actions .btn {
  padding: 8px 20px;
  font-size: 14px;
}

/* ========== Hero ========== */
.hero {
  padding: 90px 0 70px;
  background: linear-gradient(180deg, #eef3ff 0%, #fff 100%);
  text-align: center;
}

.hero-title {
  font-size: 52px;
  line-height: 1.3;
  color: var(--dark);
  font-weight: 800;
}

.hero-title em {
  font-style: normal;
  background: linear-gradient(90deg, var(--primary), #8a6ff7);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}

.hero-sub {
  max-width: 640px;
  margin: 24px auto 0;
  font-size: 17px;
  color: var(--gray);
}

.hero-actions {
  margin-top: 36px;
  display: flex;
  gap: 16px;
  justify-content: center;
}

.hero-note {
  margin-top: 18px;
  font-size: 13px;
  color: #9ca3af;
}

/* Hero 预览面板 */
.hero-preview {
  max-width: 820px;
  margin: 60px auto 0;
  background: #fff;
  border-radius: var(--radius);
  box-shadow: 0 24px 60px rgba(31, 41, 55, 0.12);
  overflow: hidden;
  text-align: left;
}

.preview-bar {
  display: flex;
  align-items: center;
  gap: 6px;
  padding: 12px 18px;
  background: #f3f5fb;
  border-bottom: 1px solid #e8ecf6;
}

.dot {
  width: 10px;
  height: 10px;
  border-radius: 50%;
}

.dot.red { background: #ff5f57; }
.dot.yellow { background: #febc2e; }
.dot.green { background: #28c840; }

.preview-url {
  margin-left: 12px;
  font-size: 12px;
  color: #9ca3af;
  background: #fff;
  padding: 3px 14px;
  border-radius: 999px;
}

.preview-body {
  display: flex;
  min-height: 300px;
}

.preview-left {
  width: 180px;
  background: #fafbfe;
  border-right: 1px solid #eef1f8;
  padding: 16px 12px;
}

.pv-item {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 10px 12px;
  margin-bottom: 4px;
  border-radius: 8px;
  font-size: 14px;
  color: var(--gray);
}

.pv-item b {
  margin-left: auto;
  font-size: 12px;
  color: #b0b7c6;
}

.pv-item.active {
  background: #e8edff;
  color: var(--primary);
  font-weight: 600;
}

.pv-ico {
  font-size: 16px;
}

.preview-main {
  flex: 1;
  padding: 16px 20px;
}

.pv-top {
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: 14px;
  font-weight: 600;
  color: var(--dark);
  margin-bottom: 12px;
}

.pv-search {
  font-size: 12px;
  font-weight: 400;
  color: #9ca3af;
  background: #f3f5fb;
  padding: 4px 12px;
  border-radius: 999px;
}

.pv-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 13px;
}

.pv-table td {
  padding: 10px 8px;
  border-bottom: 1px solid #f3f5fb;
  color: #4b5563;
}

.pv-table td:first-child {
  width: 32px;
  text-align: center;
}

.pv-table td:nth-child(3) {
  width: 90px;
  color: #9ca3af;
  font-size: 12px;
}

.pv-table .ok {
  color: #10b981;
  font-size: 12px;
  text-align: right;
}

.pv-footer {
  margin-top: 14px;
  display: flex;
  align-items: center;
  gap: 12px;
  font-size: 12px;
  color: var(--gray);
}

.pv-progress {
  flex: 1;
  height: 6px;
  background: #eef1f8;
  border-radius: 999px;
  overflow: hidden;
}

.pv-fill {
  width: 24.6%;
  height: 100%;
  background: linear-gradient(90deg, var(--primary), #8a6ff7);
  border-radius: 999px;
}

/* ========== 数据统计 ========== */
.stats {
  padding: 50px 0;
  background: #fff;
}

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

.stat b {
  display: block;
  font-size: 34px;
  color: var(--primary);
  font-weight: 800;
}

.stat span {
  font-size: 14px;
  color: var(--gray);
}

/* ========== 通用 section ========== */
.section {
  padding: 80px 0;
}

.section-dark {
  background: var(--dark);
}

.section-dark .section-title {
  color: #fff;
}

.section-dark .section-sub {
  color: #9aa3b5;
}

.section-title {
  font-size: 34px;
  font-weight: 800;
  text-align: center;
  color: var(--dark);
}

.section-sub {
  margin-top: 14px;
  text-align: center;
  color: var(--gray);
  font-size: 16px;
}

/* ========== 功能卡片 ========== */
.cards {
  margin-top: 50px;
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.card {
  background: #fff;
  border: 1px solid #eef1f8;
  border-radius: var(--radius);
  padding: 30px;
  transition: all 0.3s;
}

.card:hover {
  transform: translateY(-6px);
  box-shadow: 0 16px 36px rgba(31, 41, 55, 0.1);
  border-color: transparent;
}

.card-ico {
  width: 52px;
  height: 52px;
  border-radius: 12px;
  background: var(--light);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 26px;
  margin-bottom: 18px;
}

.card h3 {
  font-size: 18px;
  margin-bottom: 10px;
  color: var(--dark);
}

.card p {
  font-size: 14px;
  color: var(--gray);
}

/* ========== 安全保障 ========== */
.safety-grid {
  margin-top: 50px;
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.safety-item {
  background: rgba(255, 255, 255, 0.05);
  border: 1px solid rgba(255, 255, 255, 0.1);
  border-radius: var(--radius);
  padding: 32px;
  transition: all 0.3s;
}

.safety-item:hover {
  background: rgba(255, 255, 255, 0.09);
  transform: translateY(-4px);
}

.safety-item b {
  font-size: 28px;
  color: var(--primary);
  opacity: 0.7;
}

.safety-item h4 {
  margin: 12px 0 8px;
  font-size: 18px;
  color: #fff;
}

.safety-item p {
  font-size: 14px;
  color: #9aa3b5;
}

/* ========== 储存方案 ========== */
.plans {
  margin-top: 50px;
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
  align-items: stretch;
}

.plan {
  background: #fff;
  border: 1px solid #eef1f8;
  border-radius: var(--radius);
  padding: 36px 30px;
  display: flex;
  flex-direction: column;
  position: relative;
  transition: all 0.3s;
}

.plan:hover {
  transform: translateY(-6px);
  box-shadow: 0 16px 36px rgba(31, 41, 55, 0.1);
}

.plan.hot {
  border: 2px solid var(--primary);
  box-shadow: 0 16px 40px rgba(79, 110, 247, 0.18);
}

.plan-tag {
  position: absolute;
  top: -14px;
  left: 50%;
  transform: translateX(-50%);
  background: var(--primary);
  color: #fff;
  font-size: 12px;
  font-weight: 600;
  padding: 4px 16px;
  border-radius: 999px;
  white-space: nowrap;
}

.free-plan {
  max-width: 520px;
  margin: 0 auto;
  align-items: center;
  text-align: center;
  padding-top: 44px;
}

.free-plan .card-ico {
  width: 64px;
  height: 64px;
  font-size: 32px;
}

.free-plan ul {
  text-align: left;
  width: 100%;
}

.plan h3 {
  font-size: 20px;
  color: var(--dark);
}

.plan-price {
  margin: 16px 0 20px;
  display: flex;
  align-items: baseline;
  gap: 4px;
}

.plan-price b {
  font-size: 40px;
  color: var(--primary);
  font-weight: 800;
}

.plan-price span {
  color: var(--gray);
  font-size: 14px;
}

.plan ul {
  list-style: none;
  flex: 1;
  margin-bottom: 28px;
}

.plan li {
  padding: 8px 0 8px 26px;
  position: relative;
  font-size: 14px;
  color: #4b5563;
}

.plan li::before {
  content: '✓';
  position: absolute;
  left: 0;
  color: var(--primary);
  font-weight: 700;
}

/* ========== FAQ ========== */
.section-faq {
  background: var(--light);
}

.faq-list {
  max-width: 760px;
  margin: 40px auto 0;
  display: flex;
  flex-direction: column;
  gap: 14px;
}

.faq {
  background: #fff;
  border-radius: 12px;
  padding: 18px 24px;
  border: 1px solid #eef1f8;
}

.faq summary {
  cursor: pointer;
  font-size: 15px;
  font-weight: 600;
  color: var(--dark);
  list-style: none;
  position: relative;
  padding-right: 24px;
}

.faq summary::after {
  content: '+';
  position: absolute;
  right: 0;
  top: 0;
  color: var(--primary);
  font-size: 20px;
  font-weight: 400;
}

.faq[open] summary::after {
  content: '−';
}

.faq p {
  margin-top: 12px;
  font-size: 14px;
  color: var(--gray);
}

/* ========== CTA ========== */
.cta {
  padding: 90px 0;
  text-align: center;
  background: linear-gradient(135deg, var(--primary) 0%, #8a6ff7 100%);
  color: #fff;
}

.cta h2 {
  font-size: 34px;
  font-weight: 800;
}

.cta p {
  margin: 14px 0 32px;
  font-size: 16px;
  opacity: 0.9;
}

/* ========== 页脚 ========== */
.footer {
  background: var(--dark);
  color: #9aa3b5;
  padding-top: 60px;
}

.footer-inner {
  display: flex;
  justify-content: space-between;
  gap: 48px;
  padding-bottom: 40px;
}

.footer-brand .logo-text {
  color: #fff;
}

.footer-brand p {
  margin-top: 14px;
  font-size: 14px;
  max-width: 280px;
}

.footer-links {
  display: flex;
  gap: 72px;
}

.footer-links b {
  display: block;
  color: #fff;
  font-size: 15px;
  margin-bottom: 14px;
}

.footer-links a {
  display: block;
  font-size: 14px;
  margin-bottom: 10px;
  transition: color 0.2s;
}

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

.footer-bottom {
  border-top: 1px solid rgba(255, 255, 255, 0.08);
  display: flex;
  align-items: center;
  justify-content: center;
  flex-wrap: nowrap;
  white-space: nowrap;
  padding: 20px 0;
  font-size: 13px;
}

.footer-bottom a {
  display: inline-block;
  padding: 0 8px;
}

.footer-divider {
  opacity: 0.6;
}

.footer-bottom a.beian-ga {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  white-space: nowrap;
}

.beian-ga img {
  display: inline-block;
  vertical-align: middle;
  width: 18px;
  height: 18px;
}

/* ========== 内容页（隐私政策等） ========== */
.page {
  padding: 64px 0 96px;
  background: #fff;
}

.page h1 {
  font-size: 32px;
  color: var(--dark);
  margin-bottom: 8px;
}

.page-update {
  font-size: 13px;
  color: #9ca3af;
  margin-bottom: 40px;
}

.page h2 {
  font-size: 18px;
  color: var(--dark);
  margin: 28px 0 10px;
}

.page p {
  font-size: 15px;
  color: #4b5563;
  max-width: 760px;
}

/* ========== 响应式 ========== */
@media (max-width: 900px) {
  .menu {
    display: none;
  }

  .hero-title {
    font-size: 36px;
  }

  .cards,
  .plans,
  .safety-grid,
  .stats-grid {
    grid-template-columns: 1fr;
  }

  .preview-body {
    flex-direction: column;
  }

  .preview-left {
    width: 100%;
    border-right: none;
    border-bottom: 1px solid #eef1f8;
    display: flex;
    gap: 8px;
    flex-wrap: wrap;
  }

  .pv-item {
    margin-bottom: 0;
  }

  .footer-inner {
    flex-direction: column;
  }

  .footer-links {
    gap: 40px;
    flex-wrap: wrap;
  }
}

@media (max-width: 560px) {
  .hero {
    padding: 56px 0 48px;
  }

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

  .btn-lg {
    width: 240px;
  }

  .nav-actions .btn-ghost {
    display: none;
  }
}