:root {
  --green: #16a34a;
  --green-dark: #15803d;
  --green-light: #dcfce7;
  --bg: #f2f3f5;
  --card-bg: #ffffff;
  --border: #e5e7eb;
  --text: #1f2937;
  --text-muted: #6b7280;
}

* { box-sizing: border-box; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif;
  scroll-behavior: smooth;
}

.site-header {
  background: var(--card-bg);
  border-bottom: 1px solid var(--border);
  position: sticky;
  top: 0;
  z-index: 10;
}

.nav-wrap {
  max-width: 640px;
  margin: 0 auto;
  display: flex;
  justify-content: space-between;
  padding: 14px 16px;
}

.nav-wrap a {
  color: var(--text);
  text-decoration: none;
  font-size: 13px;
  font-weight: 500;
}

.nav-wrap a:hover { color: var(--green); }

.page {
  max-width: 640px;
  margin: 0 auto;
  padding: 16px;
}

.hero {
  padding: 12px 4px 20px;
}

.hero h1 {
  font-size: 24px;
  margin: 0 0 8px;
}

.subtitle {
  color: var(--text-muted);
  margin: 0 0 14px;
  font-size: 14px;
}

.tag-list {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.tag {
  background: var(--green-light);
  color: var(--green-dark);
  font-size: 12px;
  padding: 5px 12px;
  border-radius: 999px;
}

.card {
  background: var(--card-bg);
  border: 1px solid var(--border);
  border-radius: 14px;
  padding: 20px;
  margin-bottom: 16px;
}

.card h2 {
  font-size: 16px;
  margin: 0 0 14px;
}

.card h3 {
  font-size: 14px;
  margin: 18px 0 10px;
}

.feature-list {
  margin: 0;
  padding-left: 20px;
  font-size: 14px;
  line-height: 1.9;
  color: var(--text);
}

.plan-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 12px;
  margin-top: 18px;
}

.plan-option {
  position: relative;
  border: 2px solid var(--border);
  border-radius: 12px;
  padding: 16px 12px;
  text-align: center;
  cursor: pointer;
  transition: border-color .15s ease;
}

.plan-option:hover { border-color: var(--green); }

.plan-option.selected {
  border-color: var(--green);
  background: #f0fdf4;
}

.plan-tag {
  font-size: 12px;
  color: var(--text-muted);
  margin-bottom: 6px;
}

.plan-badge {
  position: absolute;
  top: -11px;
  left: 50%;
  transform: translateX(-50%);
  background: var(--green);
  color: #fff;
  font-size: 11px;
  padding: 3px 10px;
  border-radius: 999px;
  display: flex;
  align-items: center;
  gap: 4px;
  white-space: nowrap;
}

.plan-price {
  font-size: 22px;
  font-weight: 700;
  color: var(--green-dark);
  margin: 6px 0 4px;
}

.plan-desc {
  font-size: 13px;
  font-weight: 500;
}

.plan-note {
  font-size: 11px;
  color: var(--text-muted);
  margin-top: 6px;
}

.selected-bar {
  display: flex;
  justify-content: space-between;
  align-items: center;
  background: var(--green-light);
  border-radius: 10px;
  padding: 10px 14px;
  font-size: 13px;
  margin-bottom: 16px;
}

.switch-hint {
  color: var(--green-dark);
  font-size: 12px;
}

form label {
  display: block;
  font-size: 13px;
  margin: 14px 0 6px;
  color: var(--text-muted);
}

form input,
form textarea {
  width: 100%;
  padding: 10px 12px;
  border: 1px solid var(--border);
  border-radius: 8px;
  font-size: 14px;
  font-family: inherit;
  resize: vertical;
}

form input:focus,
form textarea:focus {
  outline: none;
  border-color: var(--green);
}

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

.stepper button {
  width: 32px;
  height: 32px;
  border: 1px solid var(--border);
  background: #fff;
  border-radius: 8px;
  font-size: 16px;
  cursor: pointer;
}

.stepper input {
  width: 48px;
  text-align: center;
  padding: 6px;
}

.submit-btn {
  width: 100%;
  margin-top: 20px;
  padding: 13px;
  background: var(--green);
  color: #fff;
  border: none;
  border-radius: 10px;
  font-size: 15px;
  font-weight: 600;
  cursor: pointer;
}

.submit-btn:hover { background: var(--green-dark); }

.order-result {
  margin-top: 16px;
  background: #f0fdf4;
  border: 1px solid var(--green-light);
  border-radius: 10px;
  padding: 14px;
  font-size: 13px;
  line-height: 1.8;
}

.order-result.hidden { display: none; }

.order-result button {
  border: 1px solid var(--border);
  background: #fff;
  border-radius: 6px;
  font-size: 12px;
  padding: 2px 8px;
  cursor: pointer;
}

.activate-box p {
  font-size: 14px;
  line-height: 1.9;
  margin: 4px 0;
}

.activate-box a {
  color: var(--green-dark);
}

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

.tariff-table th,
.tariff-table td {
  text-align: left;
  padding: 10px 8px;
  border-bottom: 1px solid var(--border);
}

.tariff-table th {
  color: var(--text-muted);
  font-weight: 500;
}

.faq-item {
  border-bottom: 1px solid var(--border);
}

.faq-item:last-child { border-bottom: none; }

.faq-q {
  width: 100%;
  text-align: left;
  background: none;
  border: none;
  padding: 14px 0;
  font-size: 14px;
  font-weight: 500;
  color: var(--text);
  cursor: pointer;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.faq-icon {
  color: var(--green);
  font-size: 16px;
  transition: transform .15s ease;
}

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

.faq-a {
  display: none;
  padding: 0 0 16px;
  font-size: 13px;
  color: var(--text-muted);
  line-height: 1.8;
}

.faq-item.open .faq-a { display: block; }

.contact-label {
  color: var(--text-muted);
  font-size: 13px;
  margin: 0 0 10px;
}

.qr-box {
  display: flex;
  justify-content: center;
  margin-bottom: 14px;
}

.pay-qr-row {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 20px;
  margin-top: 14px;
}

.pay-qr-item {
  text-align: center;
  flex: 1 1 220px;
  max-width: 260px;
}

.qr-small {
  width: 100%;
  height: auto;
  border: 1px solid var(--border);
  border-radius: 8px;
  display: block;
  margin: 0 auto;
}

.qr-caption {
  font-size: 12px;
  color: var(--text-muted);
  margin: 6px 0 0;
}

.qr-placeholder {
  width: 200px;
  height: auto;
  border: 1px solid var(--border);
  border-radius: 10px;
  display: block;
}

.contact-hint {
  text-align: center;
  font-size: 13px;
  color: var(--text-muted);
  margin: 6px 0;
}

.contact-hint button {
  border: 1px solid var(--border);
  background: #fff;
  border-radius: 6px;
  font-size: 12px;
  padding: 2px 8px;
  cursor: pointer;
  margin-left: 4px;
}

/* 教程：快速跳转目录 */
.toc {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 6px;
  margin-top: 14px;
}

.toc-label {
  font-size: 12px;
  color: var(--text-muted);
  margin-right: 2px;
}

.toc a {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-width: 26px;
  height: 26px;
  padding: 0 6px;
  border-radius: 999px;
  background: #fff;
  border: 1px solid var(--border);
  font-size: 12px;
  color: var(--text);
  text-decoration: none;
}

.toc a:hover {
  border-color: var(--green);
  color: var(--green-dark);
}

/* 教程：时间线步骤 */
.timeline {
  padding: 4px 4px 4px;
}

.timeline-item {
  display: flex;
  gap: 14px;
  scroll-margin-top: 70px;
}

.timeline-marker-col {
  flex: 0 0 30px;
  display: flex;
  flex-direction: column;
  align-items: center;
}

.timeline-dot {
  flex-shrink: 0;
  width: 30px;
  height: 30px;
  border-radius: 50%;
  background: var(--green);
  color: #fff;
  font-size: 13px;
  font-weight: 700;
  display: flex;
  align-items: center;
  justify-content: center;
}

.timeline-line {
  flex: 1;
  width: 2px;
  background: var(--border);
  margin: 4px 0;
}

.timeline-item:last-child .timeline-line {
  display: none;
}

.timeline-content {
  flex: 1;
  padding-bottom: 26px;
  min-width: 0;
}

.timeline-content h2 {
  font-size: 15px;
  margin: 3px 0 8px;
}

.timeline-content p {
  font-size: 14px;
  line-height: 1.8;
  margin: 0 0 8px;
}

/* 教程：提示/警告框 */
.callout {
  background: #eff6ff;
  border-left: 3px solid #3b82f6;
  color: #1e3a8a;
  border-radius: 6px;
  padding: 10px 14px;
  font-size: 13px;
  line-height: 1.7;
  margin-top: 8px;
}

.callout-warning {
  background: #fffbeb;
  border-left-color: #f59e0b;
  color: #92400e;
}

/* 教程：可点击放大的步骤截图 */
.step-img {
  width: 100%;
  border: 1px solid var(--border);
  border-radius: 10px;
  margin-top: 10px;
  display: block;
  cursor: zoom-in;
}

.lightbox-overlay {
  position: fixed;
  inset: 0;
  background: rgba(15, 23, 42, 0.85);
  display: none;
  align-items: center;
  justify-content: center;
  padding: 24px;
  z-index: 100;
  cursor: zoom-out;
}

.lightbox-overlay.open {
  display: flex;
}

.lightbox-overlay img {
  max-width: 100%;
  max-height: 100%;
  border-radius: 8px;
}

/* 教程：行内代码/号码格式 */
.kbd {
  display: inline-block;
  background: #fef2f2;
  color: #b91c1c;
  border: 1px solid #fecaca;
  border-radius: 6px;
  font-family: Consolas, "Courier New", monospace;
  font-size: 12px;
  padding: 1px 8px;
  margin: 0 2px;
  white-space: nowrap;
}

.callout-danger {
  background: #fef2f2;
  border-left: 3px solid #ef4444;
  color: #991b1b;
  border-radius: 6px;
  padding: 10px 14px;
  font-size: 13px;
  line-height: 1.7;
  margin-top: 8px;
}

/* 页面级合规提示条 */
.notice-banner {
  background: #fffbeb;
  border: 1px solid #fde68a;
  color: #92400e;
  border-radius: 10px;
  padding: 10px 14px;
  font-size: 13px;
  line-height: 1.7;
  margin-bottom: 16px;
}

/* 教程底部导流条 */
.next-step-banner {
  display: block;
  text-align: center;
  background: var(--green-light);
  border: 1px solid var(--green);
  border-radius: 14px;
  padding: 16px;
  margin-bottom: 16px;
  font-size: 14px;
  color: var(--green-dark);
  text-decoration: none;
  font-weight: 600;
}

.next-step-banner:hover {
  background: #bbf7d0;
}

/* 返回顶部 */
.back-to-top {
  position: fixed;
  right: 20px;
  bottom: 20px;
  width: 42px;
  height: 42px;
  border-radius: 50%;
  background: var(--green);
  color: #fff;
  border: none;
  font-size: 18px;
  cursor: pointer;
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.2);
  display: none;
  align-items: center;
  justify-content: center;
  z-index: 50;
}

.back-to-top.visible {
  display: flex;
}