/* ═══════════════════════════════════════════════
   Transfer Assistant — 产品推广落地页
   设计风格：Apple 式简约 + 现代渐变
   ═══════════════════════════════════════════════ */

/* ── CSS 变量 ──────────────────────────────────── */
:root {
  --primary: #4F46E5;
  --primary-dark: #3730A3;
  --primary-light: #EEF2FF;
  --accent: #818CF8;
  --accent-2: #C084FC;

  --bg: #FFFFFF;
  --bg-alt: #F8FAFC;
  --bg-gray: #F1F5F9;

  --text: #0F172A;
  --text-2: #334155;
  --text-3: #64748B;
  --text-muted: #94A3B8;

  --border: #E2E8F0;
  --border-light: #F1F5F9;

  --success: #10B981;
  --success-bg: #ECFDF5;
  --warning: #F59E0B;

  --shadow-sm: 0 1px 2px rgba(0,0,0,0.04);
  --shadow: 0 1px 3px rgba(0,0,0,0.06), 0 1px 2px rgba(0,0,0,0.04);
  --shadow-md: 0 4px 6px -1px rgba(0,0,0,0.07), 0 2px 4px -2px rgba(0,0,0,0.05);
  --shadow-lg: 0 10px 15px -3px rgba(0,0,0,0.08), 0 4px 6px -4px rgba(0,0,0,0.04);
  --shadow-xl: 0 20px 25px -5px rgba(0,0,0,0.1), 0 8px 10px -6px rgba(0,0,0,0.04);
  --shadow-glow: 0 0 40px rgba(79, 70, 229, 0.15);

  --radius-sm: 8px;
  --radius: 12px;
  --radius-lg: 16px;
  --radius-xl: 24px;
  --radius-full: 9999px;

  --font: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'PingFang SC', 'Microsoft YaHei', 'Helvetica Neue', sans-serif;

  --max-width: 1200px;
  --nav-height: 64px;
}

/* ── 全局 ──────────────────────────────────────── */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

html {
  scroll-behavior: smooth;
  scroll-padding-top: var(--nav-height);
}

body {
  font-family: var(--font);
  color: var(--text);
  background: var(--bg);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  overflow-x: hidden;
}

a { color: inherit; text-decoration: none; }
img { max-width: 100%; display: block; }

/* ── 导航栏 ────────────────────────────────────── */
.nav {
  position: fixed;
  top: 0; left: 0; right: 0;
  z-index: 100;
  height: var(--nav-height);
  background: rgba(255,255,255,0.82);
  backdrop-filter: blur(20px) saturate(180%);
  -webkit-backdrop-filter: blur(20px) saturate(180%);
  border-bottom: 1px solid transparent;
  transition: all 0.3s ease;
}

.nav.scrolled {
  border-bottom-color: var(--border);
  box-shadow: var(--shadow-sm);
}

.nav-inner {
  max-width: var(--max-width);
  margin: 0 auto;
  height: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 24px;
}

.nav-logo {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 18px;
  font-weight: 700;
  color: var(--text);
  letter-spacing: -0.5px;
}

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

.nav-links {
  display: flex;
  gap: 32px;
}

.nav-links a {
  font-size: 14px;
  font-weight: 500;
  color: var(--text-3);
  transition: color 0.2s;
}

.nav-links a:hover { color: var(--text); }

.nav-cta {
  padding: 8px 20px;
  background: var(--primary);
  color: #fff !important;
  border-radius: var(--radius-full);
  font-size: 14px;
  font-weight: 600;
  transition: all 0.2s;
}

.nav-cta:hover {
  background: var(--primary-dark);
  transform: translateY(-1px);
  box-shadow: 0 4px 12px rgba(79,70,229,0.3);
}

/* 移动端菜单按钮 */
.nav-menu-btn {
  display: none;
  background: none;
  border: none;
  font-size: 22px;
  cursor: pointer;
  color: var(--text);
  padding: 4px 8px;
}

.mobile-menu {
  display: none;
  position: absolute;
  top: var(--nav-height);
  left: 0; right: 0;
  background: rgba(255,255,255,0.98);
  backdrop-filter: blur(20px);
  padding: 16px 24px;
  flex-direction: column;
  gap: 12px;
  border-bottom: 1px solid var(--border);
  box-shadow: var(--shadow-lg);
}

.mobile-menu.open { display: flex; }

.mobile-menu a {
  font-size: 16px;
  font-weight: 500;
  padding: 8px 0;
  color: var(--text-2);
}

.mobile-cta {
  color: var(--primary) !important;
  font-weight: 600 !important;
}

/* ── Hero ──────────────────────────────────────── */
.hero {
  min-height: 100vh;
  display: flex;
  align-items: center;
  padding: calc(var(--nav-height) + 40px) 24px 80px;
  position: relative;
  overflow: hidden;
}

.hero-bg-glow {
  position: absolute;
  top: -30%;
  left: 50%;
  transform: translateX(-50%);
  width: 800px;
  height: 800px;
  background: radial-gradient(circle, rgba(79,70,229,0.06) 0%, rgba(129,140,248,0.03) 40%, transparent 70%);
  pointer-events: none;
}

.hero-inner {
  max-width: var(--max-width);
  margin: 0 auto;
  width: 100%;
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 60px;
  align-items: center;
}

.hero-text { position: relative; z-index: 1; }

.hero-badge {
  display: inline-block;
  padding: 6px 14px;
  background: var(--primary-light);
  color: var(--primary);
  font-size: 13px;
  font-weight: 600;
  border-radius: var(--radius-full);
  margin-bottom: 24px;
}

.hero-title {
  font-size: clamp(32px, 5vw, 52px);
  font-weight: 800;
  line-height: 1.15;
  letter-spacing: -1.5px;
  color: var(--text);
  margin-bottom: 20px;
}

.hero-highlight {
  background: linear-gradient(135deg, var(--primary), var(--accent-2));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero-desc {
  font-size: 18px;
  color: var(--text-3);
  line-height: 1.7;
  margin-bottom: 32px;
  max-width: 460px;
}

.hero-actions {
  display: flex;
  gap: 16px;
  flex-wrap: wrap;
  margin-bottom: 32px;
}

.btn-primary {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 14px 28px;
  background: var(--primary);
  color: #fff;
  border: none;
  border-radius: var(--radius-full);
  font-size: 16px;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.2s;
}

.btn-primary:hover {
  background: var(--primary-dark);
  transform: translateY(-2px);
  box-shadow: 0 8px 24px rgba(79,70,229,0.3);
}

.btn-outline {
  display: inline-flex;
  align-items: center;
  padding: 14px 28px;
  border: 2px solid var(--border);
  border-radius: var(--radius-full);
  font-size: 16px;
  font-weight: 600;
  color: var(--text-2);
  transition: all 0.2s;
}

.btn-outline:hover {
  border-color: var(--text);
  color: var(--text);
}

.btn-lg { padding: 16px 32px; font-size: 17px; }

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

.stat {
  font-size: 13px;
  color: var(--text-3);
}

.stat strong {
  display: block;
  font-size: 18px;
  color: var(--primary);
  font-weight: 800;
}

/* ── Hero 设备展示 ─────────────────────────────── */
.hero-devices {
  position: relative;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 20px;
}

.device-iphone {
  width: 180px;
  height: 370px;
  background: #1E293B;
  border-radius: 28px;
  padding: 10px;
  box-shadow: var(--shadow-xl), 0 0 60px rgba(79,70,229,0.1);
  position: relative;
  z-index: 2;
}

.device-iphone::before {
  content: '';
  position: absolute;
  top: 14px;
  left: 50%;
  transform: translateX(-50%);
  width: 60px;
  height: 6px;
  background: #334155;
  border-radius: 3px;
  z-index: 3;
}

.iphone-screen {
  width: 100%;
  height: 100%;
  background: #fff;
  border-radius: 20px;
  overflow: hidden;
  padding: 24px 12px 0;
  display: flex;
  flex-direction: column;
}

.mock-chat {
  flex: 1;
  display: flex;
  flex-direction: column;
  gap: 8px;
  padding: 6px;
  overflow: hidden;
}

/* iPhone 聊天输入框 */
.mock-iphone-input {
  display: flex;
  align-items: center;
  gap: 6px;
  padding: 8px 4px;
  border-top: 1px solid #e8e8e8;
  background: #fafafa;
  flex-shrink: 0;
}

.mock-input-plus {
  width: 22px; height: 22px;
  border-radius: 50%;
  border: 1.5px solid #ccc;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 14px;
  color: #999;
  font-weight: 300;
  flex-shrink: 0;
}

.mock-input-field {
  flex: 1;
  padding: 6px 10px;
  border: 1px solid #e0e0e0;
  border-radius: 16px;
  font-size: 10px;
  color: #bbb;
  background: #fff;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.mock-input-send {
  width: 26px; height: 26px;
  border-radius: 50%;
  background: var(--primary);
  color: #fff;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 14px;
  font-weight: 700;
  flex-shrink: 0;
}

/* Windows 浏览器聊天输入框 */
.mock-win-input {
  display: flex;
  align-items: center;
  gap: 6px;
  padding: 6px 10px;
  border-top: 1px solid #e8e8e8;
  background: #fafafa;
  flex-shrink: 0;
}

.mock-input-clip {
  font-size: 12px;
  color: #999;
  flex-shrink: 0;
}

.mock-input-field-win {
  font-size: 10px;
  padding: 4px 8px;
  border-radius: 4px;
  border: 1px solid #ddd;
}

.mock-input-send-win {
  width: auto;
  height: auto;
  padding: 4px 10px;
  border-radius: 4px;
  font-size: 10px;
  font-weight: 600;
}

.windows-monitor {
  display: flex;
  flex-direction: column;
  align-items: center;
}

.monitor-screen {
  width: 440px;
  height: 290px;
  background: #1a1a2e;
  border-radius: 10px;
  padding: 5px;
  box-shadow: var(--shadow-lg), 0 0 40px rgba(79,70,229,0.08);
  position: relative;
}

.monitor-stand {
  width: 80px;
  height: 6px;
  background: #d1d5db;
  border-radius: 0 0 3px 3px;
  margin: 0 auto;
}

.monitor-stand::after {
  content: '';
  display: block;
  width: 140px;
  height: 4px;
  background: #d1d5db;
  border-radius: 0 0 3px 3px;
  margin: 0 auto;
}

/* ── Windows 11 Edge 浏览器窗口 ────────────────── */
.win-browser {
  width: 100%;
  height: 100%;
  background: #fff;
  border-radius: 6px;
  overflow: hidden;
  display: flex;
  flex-direction: column;
}

/* 标题栏 + 标签页 */
.win-titlebar {
  display: flex;
  align-items: center;
  background: #f3f3f3;
  border-bottom: 1px solid #e0e0e0;
  padding: 0 6px;
  height: 32px;
  gap: 0;
  flex-shrink: 0;
}

.win-tab {
  display: flex;
  align-items: center;
  gap: 6px;
  padding: 4px 12px;
  background: #fff;
  border-radius: 6px 6px 0 0;
  font-size: 10px;
  color: #333;
  border: 1px solid #e0e0e0;
  border-bottom: 1px solid #fff;
  margin-top: 4px;
  max-width: 140px;
  white-space: nowrap;
  overflow: hidden;
}

.win-tab span {
  overflow: hidden;
  text-overflow: ellipsis;
}

.win-tab-close {
  font-size: 12px;
  color: #999;
  margin-left: 2px;
  flex-shrink: 0;
}

.win-tab-new {
  font-size: 14px;
  padding: 2px 8px;
  background: transparent;
  border: none;
  color: #666;
  margin-top: 4px;
  cursor: pointer;
}

.win-controls {
  display: flex;
  gap: 2px;
  margin-left: auto;
}

.win-controls span {
  width: 32px; height: 22px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 10px;
  color: #666;
  border-radius: 3px;
  font-family: 'Segoe UI', sans-serif;
}

.win-controls span:hover {
  background: #e0e0e0;
}

.win-controls span:last-child:hover {
  background: #e81123;
  color: #fff;
}

/* 工具栏 (导航按钮 + 地址栏) */
.win-toolbar {
  display: flex;
  align-items: center;
  gap: 6px;
  padding: 6px 8px;
  background: #f9f9f9;
  border-bottom: 1px solid #e8e8e8;
  flex-shrink: 0;
}

.win-nav-btns {
  display: flex;
  gap: 2px;
}

.win-nav-btns span {
  width: 24px; height: 24px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 12px;
  color: #666;
  border-radius: 4px;
  border: 1px solid #ddd;
  background: #fff;
}

.win-url-bar {
  flex: 1;
  display: flex;
  align-items: center;
  gap: 6px;
  padding: 3px 10px;
  background: #fff;
  border: 1px solid #ddd;
  border-radius: 14px;
  font-size: 10px;
  color: #666;
  font-family: 'Segoe UI', monospace;
  overflow: hidden;
  white-space: nowrap;
}

.win-url-lock {
  font-size: 9px;
  flex-shrink: 0;
}

.browser-chat {
  padding: 8px 10px;
  flex: 1;
  overflow: hidden;
}

.mock-msg {
  font-size: 11px;
  padding: 8px 10px;
  border-radius: 12px;
  max-width: 85%;
  line-height: 1.4;
}

.mock-sent {
  background: var(--primary);
  color: #fff;
  align-self: flex-end;
  border-bottom-right-radius: 3px;
}

.mock-received {
  background: var(--bg-gray);
  color: var(--text-2);
  align-self: flex-start;
  border-bottom-left-radius: 3px;
}

.mock-file {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 8px 10px;
  background: #fff;
  border: 1px solid var(--border);
  border-radius: 10px;
  font-size: 11px;
  align-self: flex-start;
}

.mock-file-win { align-self: flex-end; }

.mock-file-icon { font-size: 20px; }
.mock-file-size { color: var(--primary); font-weight: 600; font-size: 10px; margin-left: auto; }

.mock-photos {
  display: flex;
  gap: 4px;
  font-size: 28px;
  align-self: flex-end;
}

.browser-chat .mock-msg { font-size: 10px; max-width: 70%; }
.browser-chat .mock-file { font-size: 10px; }

/* 连接动画 */
.connection-line {
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  width: 100%;
  height: 60px;
  z-index: 0;
  opacity: 0.6;
}

.transfer-anim {
  position: absolute;
  top: -10px;
  left: 50%;
  transform: translateX(-50%);
  font-size: 12px;
  font-weight: 700;
  color: var(--primary);
  white-space: nowrap;
  animation: blink 2s infinite;
}

@keyframes blink {
  0%, 100% { opacity: 1; }
  50% { opacity: 0.4; }
}

/* ── Section 通用 ─────────────────────────────── */
section {
  padding: 100px 24px;
}

.section-header {
  text-align: center;
  max-width: 640px;
  margin: 0 auto 60px;
}

.section-tag {
  display: inline-block;
  padding: 4px 14px;
  background: var(--primary-light);
  color: var(--primary);
  font-size: 13px;
  font-weight: 700;
  border-radius: var(--radius-full);
  margin-bottom: 16px;
  letter-spacing: 0.5px;
}

.section-header h2 {
  font-size: clamp(28px, 4vw, 40px);
  font-weight: 800;
  letter-spacing: -1px;
  margin-bottom: 12px;
}

.section-header p {
  font-size: 17px;
  color: var(--text-3);
}

/* ── 使用步骤 ──────────────────────────────────── */
.how-it-works {
  background: var(--bg-alt);
}

.steps {
  display: flex;
  align-items: flex-start;
  justify-content: center;
  gap: 20px;
  max-width: 1000px;
  margin: 0 auto;
  flex-wrap: wrap;
}

.step-card {
  flex: 1;
  min-width: 250px;
  max-width: 310px;
  background: var(--bg);
  border-radius: var(--radius-xl);
  padding: 36px 28px;
  text-align: center;
  position: relative;
  box-shadow: var(--shadow);
  transition: all 0.3s;
}

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

.step-number {
  position: absolute;
  top: -14px;
  left: 50%;
  transform: translateX(-50%);
  width: 28px; height: 28px;
  border-radius: 50%;
  background: var(--primary);
  color: #fff;
  font-size: 13px;
  font-weight: 700;
  display: flex;
  align-items: center;
  justify-content: center;
}

.step-icon {
  width: 64px; height: 64px;
  border-radius: var(--radius-lg);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 32px;
  margin: 0 auto 16px;
}

.step-card h3 {
  font-size: 20px;
  font-weight: 700;
  margin-bottom: 8px;
}

.step-card p {
  font-size: 14px;
  color: var(--text-3);
  line-height: 1.6;
}

.step-time {
  display: inline-block;
  margin-top: 12px;
  font-size: 12px;
  color: var(--text-muted);
  font-weight: 500;
}

.step-arrow {
  font-size: 28px;
  color: var(--text-muted);
  align-self: center;
  flex-shrink: 0;
  padding-top: 30px;
}

/* ── 核心功能 ──────────────────────────────────── */
.features-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
  gap: 24px;
  max-width: var(--max-width);
  margin: 0 auto;
}

.feature-card {
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: var(--radius-xl);
  padding: 36px 32px;
  transition: all 0.3s;
}

.feature-card:hover {
  border-color: var(--primary);
  box-shadow: var(--shadow-glow);
  transform: translateY(-2px);
}

.feature-icon {
  width: 52px; height: 52px;
  font-size: 28px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--bg-gray);
  border-radius: var(--radius);
  margin-bottom: 20px;
}

.feature-card h3 {
  font-size: 19px;
  font-weight: 700;
  margin-bottom: 8px;
}

.feature-card p {
  font-size: 15px;
  color: var(--text-3);
  line-height: 1.6;
}

/* ── 对比表格 ──────────────────────────────────── */
.comparison {
  background: var(--bg-alt);
}

.compare-table-wrapper {
  max-width: 860px;
  margin: 0 auto;
  overflow-x: auto;
  border-radius: var(--radius-xl);
  box-shadow: var(--shadow);
}

.compare-table {
  width: 100%;
  border-collapse: collapse;
  background: var(--bg);
  border-radius: var(--radius-xl);
  overflow: hidden;
}

.compare-table th,
.compare-table td {
  padding: 16px 20px;
  text-align: center;
  font-size: 14px;
}

.compare-table thead th {
  background: var(--bg-gray);
  font-weight: 700;
  font-size: 15px;
  color: var(--text-2);
  position: sticky;
  top: 0;
}

.compare-table thead th:first-child {
  text-align: left;
  padding-left: 24px;
}

.compare-table tbody td:first-child {
  text-align: left;
  padding-left: 24px;
  font-weight: 600;
  color: var(--text-2);
  white-space: nowrap;
}

.compare-table tbody tr {
  border-top: 1px solid var(--border-light);
}

.compare-table tbody tr:hover {
  background: var(--bg-gray);
}

.col-our {
  color: var(--primary) !important;
  font-weight: 700 !important;
  background: rgba(79,70,229,0.03);
}

/* ── 使用场景 ──────────────────────────────────── */
.usecases-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 24px;
  max-width: var(--max-width);
  margin: 0 auto;
}

.usecase-card {
  text-align: center;
  padding: 36px 24px;
  background: var(--bg);
  border-radius: var(--radius-xl);
  border: 1px solid var(--border-light);
  transition: all 0.3s;
}

.usecase-card:hover {
  box-shadow: var(--shadow-md);
  transform: translateY(-2px);
}

.usecase-emoji {
  font-size: 44px;
  display: block;
  margin-bottom: 14px;
}

.usecase-card h3 {
  font-size: 18px;
  font-weight: 700;
  margin-bottom: 8px;
}

.usecase-card p {
  font-size: 14px;
  color: var(--text-3);
  line-height: 1.6;
}

/* ── CTA Banner ────────────────────────────────── */
.cta-banner {
  position: relative;
  overflow: hidden;
  margin: 0 24px 80px;
  border-radius: var(--radius-xl);
  background: linear-gradient(135deg, #1E1B4B 0%, #312E81 40%, #4F46E5 100%);
  padding: 80px 24px;
  max-width: var(--max-width);
  margin-left: auto;
  margin-right: auto;
}

.cta-glow {
  position: absolute;
  top: -100px;
  right: -100px;
  width: 400px;
  height: 400px;
  background: radial-gradient(circle, rgba(129,140,248,0.3) 0%, transparent 70%);
  pointer-events: none;
}

.cta-content {
  position: relative;
  z-index: 1;
  text-align: center;
  max-width: 560px;
  margin: 0 auto;
}

.cta-content h2 {
  font-size: 36px;
  font-weight: 800;
  color: #fff;
  margin-bottom: 12px;
  letter-spacing: -1px;
}

.cta-content p {
  font-size: 17px;
  color: rgba(255,255,255,0.7);
  margin-bottom: 36px;
}

.cta-buttons {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 20px;
  flex-wrap: wrap;
  margin-bottom: 24px;
}

.btn-appstore {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  padding: 14px 28px;
  background: #fff;
  color: var(--text);
  border-radius: var(--radius);
  font-size: 14px;
  transition: all 0.2s;
}

.btn-appstore:hover {
  transform: scale(1.03);
  box-shadow: 0 8px 24px rgba(0,0,0,0.2);
}

.btn-appstore small { font-size: 11px; opacity: 0.7; }
.btn-appstore strong { font-size: 18px; display: block; }

.cta-or {
  color: rgba(255,255,255,0.5);
  font-size: 14px;
}

.qr-code {
  width: 90px; height: 90px;
  border-radius: var(--radius-sm);
  background: #fff;
  padding: 4px;
}

.cta-note {
  font-size: 13px !important;
  color: rgba(255,255,255,0.45) !important;
}

/* ── FAQ ───────────────────────────────────────── */
.faq {
  background: var(--bg-alt);
}

.faq-list {
  max-width: 700px;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.faq-item {
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  overflow: hidden;
  transition: all 0.2s;
}

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

.faq-question {
  width: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 20px 24px;
  background: none;
  border: none;
  cursor: pointer;
  font-size: 16px;
  font-weight: 600;
  color: var(--text);
  text-align: left;
  font-family: var(--font);
  gap: 16px;
}

.faq-arrow {
  font-size: 18px;
  color: var(--text-muted);
  transition: transform 0.3s;
  flex-shrink: 0;
}

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

.faq-answer {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.35s ease, padding 0.35s ease;
}

.faq-item.open .faq-answer {
  max-height: 300px;
}

.faq-answer p {
  padding: 0 24px 20px;
  font-size: 15px;
  color: var(--text-3);
  line-height: 1.7;
}

/* ── Footer ────────────────────────────────────── */
.footer {
  background: var(--text);
  color: rgba(255,255,255,0.7);
  padding: 60px 24px 30px;
}

.footer-inner {
  max-width: var(--max-width);
  margin: 0 auto;
  display: grid;
  grid-template-columns: 1.5fr 2fr;
  gap: 60px;
  padding-bottom: 40px;
  border-bottom: 1px solid rgba(255,255,255,0.1);
}

.footer-logo {
  font-size: 20px;
  font-weight: 700;
  color: #fff;
  margin-bottom: 12px;
  display: block;
}

.footer-brand p {
  font-size: 14px;
  line-height: 1.6;
}

.footer-links {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.footer-col h4 {
  color: #fff;
  font-size: 13px;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.5px;
  margin-bottom: 16px;
}

.footer-col a {
  display: block;
  font-size: 14px;
  padding: 4px 0;
  transition: color 0.2s;
}

.footer-col a:hover { color: #fff; }

.footer-bottom {
  max-width: var(--max-width);
  margin: 0 auto;
  padding-top: 24px;
  text-align: center;
  font-size: 13px;
  color: rgba(255,255,255,0.4);
}

/* ── 入场动画（通过 JS 触发）─────────────────────── */
.animate-in {
  opacity: 0;
  transform: translateY(30px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}

.animate-in.visible {
  opacity: 1;
  transform: translateY(0);
}

/* ── 响应式 ────────────────────────────────────── */
@media (max-width: 968px) {
  .hero-inner {
    grid-template-columns: 1fr;
    gap: 40px;
    text-align: center;
  }

  .hero-desc { max-width: 100%; }
  .hero-actions { justify-content: center; }
  .hero-stats { justify-content: center; }

  .hero-devices {
    transform: scale(0.75);
    flex-direction: column;
  }

  .monitor-screen { width: 360px; height: 240px; }

  .connection-line { display: none; }

  .steps { flex-direction: column; align-items: center; }
  .step-arrow { transform: rotate(90deg); padding: 0; }
  .step-card { max-width: 400px; width: 100%; }

  .nav-links { display: none; }
  .nav-cta { display: none; }
  .nav-menu-btn { display: block; }

  .footer-inner {
    grid-template-columns: 1fr;
    gap: 40px;
  }

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

@media (max-width: 640px) {
  section { padding: 60px 16px; }

  .hero { padding: calc(var(--nav-height) + 20px) 16px 40px; }
  .hero-badge { font-size: 12px; }
  .hero-title { font-size: 28px; }
  .hero-desc { font-size: 15px; }
  .hero-devices { transform: scale(0.55); margin: -40px 0; }

  .features-grid { grid-template-columns: 1fr; }
  .usecases-grid { grid-template-columns: 1fr; }
  .compare-table th, .compare-table td { padding: 10px 12px; font-size: 12px; }

  .cta-content h2 { font-size: 26px; }
  .cta-banner { padding: 50px 20px; margin: 0 12px 40px; }

  .faq-question { font-size: 14px; padding: 16px; }
  .faq-answer p { font-size: 13px; padding: 0 16px 16px; }

  .footer-links { grid-template-columns: 1fr; gap: 16px; }
}