/* ============================================
   AY知识库 - 现代化样式
   modern.css
   ============================================ */

/* ---------- CSS 变量 ---------- */
:root {
  --primary: #667eea;
  --primary-dark: #5a6fd6;
  --primary-light: #8b9ff0;
  --secondary: #764ba2;
  --accent: #f093fb;
  --gradient-main: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  --gradient-warm: linear-gradient(135deg, #f093fb 0%, #f5576c 100%);
  --gradient-cool: linear-gradient(135deg, #4facfe 0%, #00f2fe 100%);
  --gradient-green: linear-gradient(135deg, #43e97b 0%, #38f9d7 100%);

  --text-primary: #1a202c;
  --text-secondary: #4a5568;
  --text-muted: #718096;
  --text-light: #a0aec0;

  --bg-white: #ffffff;
  --bg-light: #f7fafc;
  --bg-dark: #1a202c;
  --bg-darker: #0f1419;

  --border-color: #e2e8f0;
  --border-light: #f0f4f8;

  --shadow-xs: 0 1px 3px rgba(0, 0, 0, 0.06);
  --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.08);
  --shadow-md: 0 4px 20px rgba(0, 0, 0, 0.10);
  --shadow-lg: 0 8px 40px rgba(0, 0, 0, 0.14);
  --shadow-xl: 0 16px 60px rgba(0, 0, 0, 0.18);
  --shadow-color: 0 8px 40px rgba(102, 126, 234, 0.30);

  --radius-sm: 8px;
  --radius-md: 12px;
  --radius-lg: 20px;
  --radius-xl: 28px;
  --radius-full: 9999px;

  --transition-fast: all 0.2s cubic-bezier(0.4, 0, 0.2, 1);
  --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  --transition-slow: all 0.5s cubic-bezier(0.4, 0, 0.2, 1);

  --nav-height: 70px;
  --section-padding: 100px 0;
}

/* ---------- Reset & Base ---------- */
*,
*::before,
*::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  scroll-behavior: smooth;
  font-size: 16px;
}

body {
  font-family: 'Noto Sans SC', -apple-system, BlinkMacSystemFont,
    'Segoe UI', 'PingFang SC', 'Hiragino Sans GB',
    'Microsoft YaHei', sans-serif;
  color: var(--text-primary);
  background: var(--bg-white);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  overflow-x: hidden;
}

img {
  max-width: 100%;
  height: auto;
  display: block;
}

a {
  text-decoration: none;
  transition: var(--transition);
}

ul {
  list-style: none;
  padding: 0;
  margin: 0;
}

/* ---------- 滚动条 ---------- */
::-webkit-scrollbar {
  width: 6px;
}

::-webkit-scrollbar-track {
  background: var(--bg-light);
}

::-webkit-scrollbar-thumb {
  background: var(--primary);
  border-radius: var(--radius-full);
}

::-webkit-scrollbar-thumb:hover {
  background: var(--primary-dark);
}

/* ---------- Preloader ---------- */
#preloader {
  position: fixed;
  inset: 0;
  background: var(--bg-white);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 9999;
  transition: opacity 0.5s ease, visibility 0.5s ease;
}

#preloader.hidden {
  opacity: 0;
  visibility: hidden;
}

.pre-inner {
  text-align: center;
}

.pre-logo {
  font-size: 2rem;
  font-weight: 900;
  color: var(--text-primary);
  margin-bottom: 1.5rem;
  letter-spacing: -0.5px;
}

.pre-logo span {
  background: var(--gradient-main);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.pre-bar {
  width: 200px;
  height: 3px;
  background: var(--border-color);
  border-radius: var(--radius-full);
  overflow: hidden;
}

.pre-bar-inner {
  height: 100%;
  width: 0;
  background: var(--gradient-main);
  border-radius: var(--radius-full);
  animation: preload 1.5s ease forwards;
}

@keyframes preload {
  to { width: 100%; }
}

/* ---------- 通用区块 ---------- */
.section-wrap {
  padding: var(--section-padding);
  position: relative;
  overflow: hidden;
}

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

.section-tag {
  display: inline-block;
  padding: 6px 18px;
  background: rgba(102, 126, 234, 0.1);
  color: var(--primary);
  border-radius: var(--radius-full);
  font-size: 0.85rem;
  font-weight: 600;
  letter-spacing: 0.5px;
  margin-bottom: 16px;
  border: 1px solid rgba(102, 126, 234, 0.2);
}

.section-title {
  font-size: 2.4rem;
  font-weight: 800;
  color: var(--text-primary);
  line-height: 1.3;
  margin-bottom: 16px;
  letter-spacing: -0.5px;
}

.section-subtitle {
  font-size: 1.05rem;
  color: var(--text-muted);
  line-height: 1.8;
}

/* ---------- 导航 ---------- */
.ay-nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  height: var(--nav-height);
  transition: var(--transition);
  background: transparent;
  margin: 0;
}

.ay-nav.scrolled {
  background: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  box-shadow: 0 1px 0 rgba(0, 0, 0, 0.08), var(--shadow-sm);
}

.ay-nav.scrolled .nav-link {
  color: var(--text-primary);
}

.ay-nav.scrolled .nav-link:hover {
  color: var(--primary);
}

.ay-nav.scrolled .ay-nav-brand {
  color: var(--text-primary);
}

.ay-nav.scrolled .ay-nav-toggle span {
  background: var(--text-primary);
}

.ay-nav-container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 100%;
  padding: 0 20px;
  max-width: 1200px;
  margin: 0 auto;
  width: 100%;
}

.ay-nav-brand {
  font-size: 1.4rem;
  font-weight: 800;
  color: white;
  letter-spacing: -0.5px;
  flex-shrink: 0;
}

.brand-highlight {
  background: var(--gradient-main);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.ay-nav.scrolled .brand-highlight {
  background: var(--gradient-main);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.ay-nav-menu {
  display: flex;
  align-items: center;
  gap: 4px;
}

.nav-link {
  display: block;
  padding: 8px 14px;
  color: rgba(255, 255, 255, 0.9);
  font-size: 0.9rem;
  font-weight: 500;
  border-radius: var(--radius-sm);
  transition: var(--transition-fast);
  white-space: nowrap;
}

.nav-link:hover,
.nav-link.active {
  color: white;
  background: rgba(255, 255, 255, 0.15);
}

.ay-nav.scrolled .nav-link:hover,
.ay-nav.scrolled .nav-link.active {
  color: var(--primary);
  background: rgba(102, 126, 234, 0.08);
}

.nav-cta {
  background: var(--gradient-main);
  color: white !important;
  padding: 8px 20px;
  border-radius: var(--radius-full);
  font-weight: 600;
  margin-left: 8px;
  box-shadow: 0 4px 15px rgba(102, 126, 234, 0.4);
}

.nav-cta:hover {
  transform: translateY(-2px);
  box-shadow: 0 6px 20px rgba(102, 126, 234, 0.5);
  background: var(--gradient-main) !important;
  color: white !important;
}

/* 汉堡菜单 */
.ay-nav-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  padding: 8px;
  background: transparent;
  border: none;
  cursor: pointer;
  border-radius: var(--radius-sm);
}

.ay-nav-toggle span {
  display: block;
  width: 22px;
  height: 2px;
  background: white;
  border-radius: 2px;
  transition: var(--transition-fast);
}

.ay-nav-toggle.open span:nth-child(1) {
  transform: translateY(7px) rotate(45deg);
}

.ay-nav-toggle.open span:nth-child(2) {
  opacity: 0;
  transform: scaleX(0);
}

.ay-nav-toggle.open span:nth-child(3) {
  transform: translateY(-7px) rotate(-45deg);
}

/* ---------- Hero ---------- */
.header-section {
  position: relative;
  overflow: hidden;
  margin-top: 0;
  padding-top: 0;
}

.hero-wrap {
  min-height: 100vh;
  position: relative;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--bg-darker);
}

#hero-canvas {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
}

.hero-overlay {
  position: absolute;
  inset: 0;
  background: linear-gradient(
    135deg,
    rgba(102, 126, 234, 0.85) 0%,
    rgba(118, 75, 162, 0.85) 50%,
    rgba(26, 32, 44, 0.9) 100%
  );
  z-index: 1;
}

.hero-content {
  position: relative;
  z-index: 2;
  text-align: center;
  padding-top: var(--nav-height);
}

.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 8px 20px;
  background: rgba(255, 255, 255, 0.15);
  border: 1px solid rgba(255, 255, 255, 0.25);
  border-radius: var(--radius-full);
  color: rgba(255, 255, 255, 0.95);
  font-size: 0.9rem;
  font-weight: 500;
  margin-bottom: 28px;
  backdrop-filter: blur(10px);
  animation: fadeInDown 0.8s ease both;
}

.hero-badge i {
  color: #ffd700;
}

.hero-title {
  font-size: clamp(2.8rem, 6vw, 5rem);
  font-weight: 900;
  color: white;
  line-height: 1.15;
  margin-bottom: 24px;
  letter-spacing: -1px;
  animation: fadeInUp 0.8s ease 0.1s both;
}

.hero-title-gradient {
  background: linear-gradient(135deg, #f093fb 0%, #f5576c 50%, #fda085 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero-subtitle {
  font-size: clamp(1rem, 2vw, 1.25rem);
  color: rgba(255, 255, 255, 0.85);
  max-width: 520px;
  margin: 0 auto 40px;
  line-height: 1.8;
  animation: fadeInUp 0.8s ease 0.2s both;
}

.hero-actions {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 16px;
  flex-wrap: wrap;
  margin-bottom: 60px;
  animation: fadeInUp 0.8s ease 0.3s both;
}

.btn-hero {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  padding: 14px 32px;
  border-radius: var(--radius-full);
  font-size: 1rem;
  font-weight: 600;
  cursor: pointer;
  transition: var(--transition);
  border: 2px solid transparent;
}

.btn-hero-solid {
  background: white;
  color: var(--primary);
  border-color: white;
  box-shadow: 0 8px 30px rgba(255, 255, 255, 0.3);
}

.btn-hero-solid:hover {
  transform: translateY(-3px);
  box-shadow: 0 12px 40px rgba(255, 255, 255, 0.4);
  color: var(--primary-dark);
}

.btn-hero-outline {
  background: transparent;
  color: white;
  border-color: rgba(255, 255, 255, 0.6);
  backdrop-filter: blur(10px);
}

.btn-hero-outline:hover {
  background: rgba(255, 255, 255, 0.15);
  border-color: white;
  color: white;
  transform: translateY(-3px);
}

/* Hero 统计 */
.hero-stats {
  display: inline-flex;
  align-items: center;
  gap: 0;
  background: rgba(255, 255, 255, 0.1);
  border: 1px solid rgba(255, 255, 255, 0.2);
  border-radius: var(--radius-xl);
  padding: 20px 40px;
  backdrop-filter: blur(15px);
  animation: fadeInUp 0.8s ease 0.4s both;
}

.stat-item {
  text-align: center;
  padding: 0 24px;
}

.stat-num {
  font-size: 2rem;
  font-weight: 900;
  color: white;
  line-height: 1;
}

.stat-unit {
  font-size: 1.2rem;
  font-weight: 700;
  color: rgba(255, 255, 255, 0.8);
}

.stat-label {
  display: block;
  font-size: 0.8rem;
  color: rgba(255, 255, 255, 0.65);
  margin-top: 4px;
  letter-spacing: 0.5px;
}

.stat-divider {
  width: 1px;
  height: 40px;
  background: rgba(255, 255, 255, 0.2);
  flex-shrink: 0;
}

/* 向下滚动按钮 */
.scroll-down-btn {
  position: absolute;
  bottom: 40px;
  left: 50%;
  transform: translateX(-50%);
  z-index: 2;
  width: 44px;
  height: 44px;
  border: 2px solid rgba(255, 255, 255, 0.5);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  color: white;
  font-size: 1.2rem;
  animation: scrollBounce 2s ease infinite;
  transition: var(--transition);
}

.scroll-down-btn:hover {
  background: rgba(255, 255, 255, 0.2);
  border-color: white;
  color: white;
  transform: translateX(-50%) translateY(-4px);
}

@keyframes scrollBounce {
  0%, 100% { transform: translateX(-50%) translateY(0); }
  50%       { transform: translateX(-50%) translateY(8px); }
}

/* ---------- Features ---------- */
.features-section {
  background: var(--bg-light);
}

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

.feature-card {
  background: var(--bg-white);
  border-radius: var(--radius-lg);
  padding: 32px 28px;
  border: 1px solid var(--border-light);
  transition: var(--transition);
  position: relative;
  overflow: hidden;
  cursor: default;
}

.feature-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: var(--gradient-main);
  transform: scaleX(0);
  transform-origin: left;
  transition: var(--transition);
}

.feature-card:hover {
  transform: translateY(-8px);
  box-shadow: var(--shadow-lg);
  border-color: transparent;
}

.feature-card:hover::before {
  transform: scaleX(1);
}

.feature-card-icon {
  width: 60px;
  height: 60px;
  border-radius: var(--radius-md);
  background: color-mix(in srgb, var(--icon-color) 12%, transparent);
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 20px;
  font-size: 1.5rem;
  color: var(--icon-color);
  transition: var(--transition);
}

.feature-card:hover .feature-card-icon {
  background: var(--icon-color);
  color: white;
  transform: scale(1.1) rotate(-5deg);
}

.feature-card-title {
  font-size: 1.1rem;
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: 10px;
}

.feature-card-desc {
  font-size: 0.9rem;
  color: var(--text-muted);
  line-height: 1.7;
  margin-bottom: 20px;
}

.feature-card-link {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-size: 0.875rem;
  font-weight: 600;
  color: var(--primary);
  transition: var(--transition-fast);
}

.feature-card-link:hover {
  gap: 10px;
  color: var(--primary-dark);
}

.feature-card-link i {
  font-size: 0.75rem;
}

.feature-card-special {
  background: linear-gradient(135deg, #fff8f0 0%, #fff0f8 100%);
  border-color: rgba(253, 112, 67, 0.15);
}

.feature-card-badge {
  position: absolute;
  top: 16px;
  right: 16px;
  padding: 4px 10px;
  background: var(--gradient-warm);
  color: white;
  font-size: 0.7rem;
  font-weight: 700;
  border-radius: var(--radius-full);
  letter-spacing: 0.5px;
}

/* ---------- Services ---------- */
.services-section {
  background: var(--bg-white);
}

.services-bg-shape {
  position: absolute;
  top: -200px;
  right: -200px;
  width: 600px;
  height: 600px;
  background: radial-gradient(circle, rgba(102, 126, 234, 0.06) 0%, transparent 70%);
  border-radius: 50%;
  pointer-events: none;
}

.services-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 28px;
}

.service-card {
  display: flex;
  gap: 24px;
  padding:  32px;
  background: var(--bg-white);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-lg);
  transition: var(--transition);
  position: relative;
  overflow: hidden;
}

.service-card::after {
  content: '';
  position: absolute;
  inset: 0;
  background: var(--gradient-main);
  opacity: 0;
  transition: var(--transition);
  z-index: 0;
  border-radius: var(--radius-lg);
}

.service-card:hover {
  transform: translateY(-6px);
  box-shadow: var(--shadow-lg);
  border-color: transparent;
}

.service-card:hover::after {
  opacity: 0.04;
}

.service-card-left,
.service-card-right {
  position: relative;
  z-index: 1;
}

.service-card-left {
  flex-shrink: 0;
}

.service-icon-wrap {
  width: 64px;
  height: 64px;
  border-radius: var(--radius-md);
  background: linear-gradient(135deg, rgba(102,126,234,0.12) 0%, rgba(118,75,162,0.12) 100%);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.6rem;
  color: var(--primary);
  transition: var(--transition);
}

.service-card:hover .service-icon-wrap {
  background: var(--gradient-main);
  color: white;
  transform: rotate(-8deg) scale(1.05);
}

.service-card-title {
  font-size: 1.15rem;
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: 10px;
}

.service-card-desc {
  font-size: 0.92rem;
  color: var(--text-muted);
  line-height: 1.8;
  margin-bottom: 16px;
}

.service-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.service-tags span {
  padding: 4px 12px;
  background: rgba(102,126,234,0.08);
  color: var(--primary);
  border-radius: var(--radius-full);
  font-size: 0.78rem;
  font-weight: 600;
  border: 1px solid rgba(102,126,234,0.15);
  transition: var(--transition-fast);
}

.service-card:hover .service-tags span {
  background: rgba(102,126,234,0.15);
}

/* ---------- Steps ---------- */
.steps-section {
  background: var(--bg-light);
}

.steps-timeline {
  max-width: 900px;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  gap: 0;
}

.step-item {
  display: flex;
  gap: 32px;
  position: relative;
}

.step-left {
  display: flex;
  flex-direction: column;
  align-items: center;
  flex-shrink: 0;
  width: 80px;
}

.step-number {
  width: 72px;
  height: 72px;
  border-radius: 50%;
  background: var(--gradient-main);
  color: white;
  font-size: 1.4rem;
  font-weight: 900;
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: var(--shadow-color);
  flex-shrink: 0;
  letter-spacing: -1px;
  position: relative;
  z-index: 1;
}

.step-line {
  width: 2px;
  flex: 1;
  min-height: 40px;
  background: linear-gradient(to bottom, rgba(102,126,234,0.4), rgba(102,126,234,0.1));
  margin: 8px 0;
}

.step-right {
  flex: 1;
  padding-bottom: 48px;
}

.step-card {
  background: var(--bg-white);
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: var(--shadow-sm);
  border: 1px solid var(--border-light);
  display: flex;
  transition: var(--transition);
}

.step-card:hover {
  box-shadow: var(--shadow-lg);
  transform: translateX(6px);
}

.step-item-reverse .step-card:hover {
  transform: translateX(-6px);
}

.step-card-img {
  width: 220px;
  flex-shrink: 0;
  overflow: hidden;
  background: linear-gradient(135deg, rgba(102,126,234,0.08), rgba(118,75,162,0.08));
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 24px;
}

.step-card-img img {
  width: 100%;
  height: auto;
  object-fit: contain;
  transition: var(--transition);
}

.step-card:hover .step-card-img img {
  transform: scale(1.05);
}

.step-card-img-icon {
  background: var(--gradient-main);
}

.step-icon-circle {
  width: 80px;
  height: 80px;
  border-radius: 50%;
  background: rgba(255,255,255,0.2);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 2rem;
  color: white;
}

.step-card-content {
  padding: 32px;
  flex: 1;
}

.step-tag {
  display: inline-block;
  padding: 4px 14px;
  background: rgba(102,126,234,0.1);
  color: var(--primary);
  border-radius: var(--radius-full);
  font-size: 0.78rem;
  font-weight: 700;
  letter-spacing: 0.5px;
  margin-bottom: 12px;
  text-transform: uppercase;
}

.step-card-title {
  font-size: 1.35rem;
  font-weight: 800;
  color: var(--text-primary);
  margin-bottom: 12px;
  letter-spacing: -0.3px;
}

.step-card-desc {
  font-size: 0.92rem;
  color: var(--text-secondary);
  line-height: 1.8;
  margin-bottom: 16px;
}

.step-list {
  display: flex;
  flex-direction: column;
  gap: 8px;
  margin-bottom: 24px;
}

.step-list li {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 0.9rem;
  color: var(--text-secondary);
}

.step-list li i {
  color: var(--primary);
  font-size: 0.85rem;
  flex-shrink: 0;
}

.step-actions {
  display: flex;
  gap: 12px;
  flex-wrap: wrap;
}

.btn-step {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 10px 22px;
  border-radius: var(--radius-full);
  font-size: 0.88rem;
  font-weight: 600;
  transition: var(--transition);
  cursor: pointer;
  border: 2px solid transparent;
}

.btn-step-primary {
  background: var(--gradient-main);
  color: white;
  box-shadow: 0 4px 15px rgba(102,126,234,0.35);
}

.btn-step-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 6px 20px rgba(102,126,234,0.45);
  color: white;
}

.btn-step-ghost {
  background: transparent;
  color: var(--primary);
  border-color: rgba(102,126,234,0.35);
}

.btn-step-ghost:hover {
  background: rgba(102,126,234,0.08);
  border-color: var(--primary);
  color: var(--primary);
  transform: translateY(-2px);
}

/* ---------- Screenshots ---------- */
.screenshots-section {
  background: var(--bg-white);
}

.screenshots-tabs {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 12px;
  margin-bottom: 40px;
}

.tab-btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 10px 28px;
  border-radius: var(--radius-full);
  font-size: 0.9rem;
  font-weight: 600;
  cursor: pointer;
  border: 2px solid var(--border-color);
  background: transparent;
  color: var(--text-muted);
  transition: var(--transition);
}

.tab-btn:hover {
  border-color: var(--primary);
  color: var(--primary);
  background: rgba(102,126,234,0.05);
}

.tab-btn.active {
  background: var(--gradient-main);
  border-color: transparent;
  color: white;
  box-shadow: 0 4px 15px rgba(102,126,234,0.35);
}

.screenshots-display {
  position: relative;
  max-width: 900px;
  margin: 0 auto;
}

.screenshot-panel {
  display: none;
  animation: fadeIn 0.4s ease;
}

.screenshot-panel.active {
  display: block;
}

@keyframes fadeIn {
  from { opacity: 0; transform: translateY(10px); }
  to   { opacity: 1; transform: translateY(0); }
}

.screenshot-frame {
  background: var(--bg-light);
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: var(--shadow-xl);
  border: 1px solid var(--border-color);
  margin-bottom: 24px;
}

.screenshot-frame.dark-frame {
  background: #1e2330;
  border-color: #2d3748;
}

.frame-bar {
  display: flex;
  align-items: center;
  gap: 6px;
  padding: 12px 16px;
  background: rgba(0,0,0,0.05);
  border-bottom: 1px solid rgba(0,0,0,0.06);
}

.dark-frame .frame-bar {
  background: rgba(255,255,255,0.04);
  border-bottom-color: rgba(255,255,255,0.06);
}

.frame-dot {
  width: 12px;
  height: 12px;
  border-radius: 50%;
  flex-shrink: 0;
}

.dot-red    { background: #ff5f57; }
.dot-yellow { background: #ffbd2e; }
.dot-green  { background: #28c840; }

.frame-url {
  flex: 1;
  text-align: center;
  font-size: 0.78rem;
  color: var(--text-muted);
  background: rgba(0,0,0,0.06);
  padding: 3px 12px;
  border-radius: 4px;
  margin: 0 60px;
}

.dark-frame .frame-url {
  background: rgba(255,255,255,0.08);
  color: rgba(255,255,255,0.5);
}

.screenshot-frame img {
  width: 100%;
  display: block;
}

.screenshot-info {
  text-align: center;
  padding: 16px;
}

.screenshot-info h4 {
  font-size: 1.1rem;
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: 6px;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
}

.screenshot-info p {
  font-size: 0.9rem;
  color: var(--text-muted);
}

/* ---------- Pricing ---------- */
.pricing-section {
  background: var(--bg-light);
  position: relative;
}

.pricing-bg {
  position: absolute;
  inset: 0;
  background:
    radial-gradient(ellipse at 20% 50%, rgba(102,126,234,0.07) 0%, transparent 60%),
    radial-gradient(ellipse at 80% 50%, rgba(118,75,162,0.07) 0%, transparent 60%);
  pointer-events: none;
}

.pricing-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
  align-items: stretch;
  position: relative;
  z-index: 1;
}

.pricing-card {
  background: var(--bg-white);
  border-radius: var(--radius-lg);
  padding: 36px 28px;
  border: 2px solid var(--border-light);
  transition: var(--transition);
  position: relative;
  overflow: hidden;
  display: flex;
  flex-direction: column;
}

.pricing-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 4px;
  background: var(--gradient-main);
  transform: scaleX(0);
  transition: var(--transition);
}

.pricing-card:hover {
  transform: translateY(-8px);
  box-shadow: var(--shadow-lg);
  border-color: rgba(102,126,234,0.2);
}

.pricing-card:hover::before {
  transform: scaleX(1);
}

.pricing-card-popular {
  border-color: var(--primary);
  transform: translateY(-8px);
  box-shadow: var(--shadow-color);
}

.pricing-card-popular::before {
  transform: scaleX(1);
}

.pricing-card-popular:hover {
  transform: translateY(-14px);
}

.pricing-card-enterprise {
  background: linear-gradient(135deg, #1a202c 0%, #2d3748 100%);
  border-color: transparent;
}

.pricing-card-enterprise .pricing-plan-name,
.pricing-card-enterprise .price-amount,
.pricing-card-enterprise .price-period,
.pricing-card-enterprise .price-currency {
  color: white;
}

.pricing-card-enterprise .pricing-features li {
  color: rgba(255,255,255,0.8);
  border-bottom-color: rgba(255,255,255,0.08);
}

.pricing-card-enterprise .feat-yes i {
  color: #43e97b;
}

.pricing-card-enterprise:hover {
  box-shadow: 0 8px 40px rgba(0,0,0,0.4);
}

.popular-badge,
.enterprise-badge {
  position: absolute;
  top: 16px;
  right: -1px;
  padding: 5px 14px;
  font-size: 0.72rem;
  font-weight: 700;
  letter-spacing: 0.5px;
  border-radius: var(--radius-sm) 0 0 var(--radius-sm);
}

.popular-badge {
  background: var(--gradient-main);
  color: white;
}

.enterprise-badge {
  background: var(--gradient-warm);
  color: white;
}

.pricing-card-header {
  text-align: center;
  padding-bottom: 24px;
  margin-bottom: 24px;
  border-bottom: 1px solid var(--border-light);
}

.pricing-card-enterprise .pricing-card-header {
  border-bottom-color: rgba(255,255,255,0.1);
}

.pricing-icon {
  width: 56px;
  height: 56px;
  border-radius: var(--radius-md);
  background: rgba(102,126,234,0.1);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.4rem;
  color: var(--primary);
  margin: 0 auto 16px;
  transition: var(--transition);
}

.pricing-card:hover .pricing-icon,
.pricing-card-popular .pricing-icon {
  background: var(--gradient-main);
  color: white;
}

.pricing-card-enterprise .pricing-icon {
  background: rgba(255,255,255,0.1);
  color: white;
}

.pricing-plan-name {
  font-size: 1.2rem;
  font-weight: 800;
  color: var(--text-primary);
  margin-bottom: 12px;
}

.pricing-price {
  display: flex;
  align-items: baseline;
  justify-content: center;
  gap: 4px;
  flex-wrap: wrap;
}

.price-currency {
  font-size: 1.4rem;
  font-weight: 700;
  color: var(--primary);
}

.price-amount {
  font-size: 2.8rem;
  font-weight: 900;
  color: var(--primary);
  line-height: 1;
  letter-spacing: -1px;
}

.price-period {
  font-size: 0.85rem;
  color: var(--text-muted);
  font-weight: 500;
}

.price-free {
  font-size: 1.5rem;
  font-weight: 800;
  color: var(--primary);
}

.pricing-features {
  margin-bottom: 28px;
  display: flex;
  flex-direction: column;
  gap: 0;
  flex: 1;
}

.pricing-features li {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 10px 0;
  font-size: 0.88rem;
  color: var(--text-secondary);
  border-bottom: 1px solid var(--border-light);
}

.pricing-features li:last-child {
  border-bottom: none;
}

.feat-yes i {
  color: #43e97b;
  font-size: 0.8rem;
  flex-shrink: 0;
}

.feat-no {
  opacity: 0.4;
}

.feat-no i {
  color: var(--text-muted);
  font-size: 0.8rem;
  flex-shrink: 0;
}

.pricing-action {
  text-align: center;
}

.btn-pricing {
  display: inline-block;
  width: 100%;
  padding: 12px 24px;
  border-radius: var(--radius-full);
  font-size: 0.9rem;
  font-weight: 700;
  text-align: center;
  transition: var(--transition);
  cursor: pointer;
  border: 2px solid transparent;
}

.btn-pricing-outline {
  background: transparent;
  color: var(--primary);
  border-color: rgba(102,126,234,0.4);
}

.btn-pricing-outline:hover {
  background: rgba(102,126,234,0.08);
  border-color: var(--primary);
  color: var(--primary);
  transform: translateY(-2px);
}

.btn-pricing-solid {
  background: var(--gradient-main);
  color: white;
  box-shadow: 0 4px 15px rgba(102,126,234,0.35);
}

.btn-pricing-solid:hover {
  transform: translateY(-3px);
  box-shadow: 0 8px 25px rgba(102,126,234,0.5);
  color: white;
}

.btn-pricing-enterprise {
  background: linear-gradient(135deg, #f093fb 0%, #f5576c 100%);
  color: white;
  box-shadow: 0 4px 15px rgba(245,87,108,0.3);
}

.btn-pricing-enterprise:hover {
  transform: translateY(-3px);
  box-shadow: 0 8px 25px rgba(245,87,108,0.45);
  color: white;
}

.pricing-note {
  text-align: center;
  margin-top: 40px;
  font-size: 0.875rem;
  color: var(--text-muted);
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
}

.pricing-note i {
  color: var(--primary);
}

.pricing-note a {
  color: var(--primary);
  font-weight: 600;
  text-decoration: underline;
  text-underline-offset: 3px;
}

/* ---------- Enter Section ---------- */
.enter-section {
  background: var(--bg-darker);
  position: relative;
  text-align: center;
  overflow: hidden;
}

.enter-bg {
  position: absolute;
  inset: 0;
  overflow: hidden;
}

.enter-shape {
  position: absolute;
  border-radius: 50%;
  filter: blur(60px);
  opacity: 0.5;
}

.shape-1 {
  width: 500px;
  height: 500px;
  background: rgba(102,126,234,0.3);
  top: -150px;
  left: -100px;
}

.shape-2 {
  width: 400px;
  height: 400px;
  background: rgba(118,75,162,0.3);
  bottom: -100px;
  right: -100px;
}

.shape-3 {
  width: 300px;
  height: 300px;
  background: rgba(240,147,251,0.2);
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
}

.enter-content {
  position: relative;
  z-index: 1;
}

.enter-content .section-tag {
  background: rgba(255,255,255,0.1);
  color: rgba(255,255,255,0.9);
  border-color: rgba(255,255,255,0.2);
}

.enter-title {
  font-size: clamp(2.2rem, 5vw, 3.5rem);
  font-weight: 900;
  color: white;
  margin: 16px 0;
  letter-spacing: -1px;
}

.enter-subtitle {
  font-size: 1.1rem;
  color: rgba(255,255,255,0.7);
  line-height: 1.8;
  margin-bottom: 40px;
}

.btn-enter {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  padding: 18px 48px;
  background: white;
  color: var(--primary);
  border-radius: var(--radius-full);
  font-size: 1.05rem;
  font-weight: 700;
  box-shadow: 0 8px 40px rgba(255,255,255,0.2);
  transition: var(--transition);
  margin-bottom: 32px;
}

.btn-enter:hover {
  transform: translateY(-4px);
  box-shadow: 0 16px 50px rgba(255,255,255,0.3);
  color: var(--primary-dark);
}

.btn-enter i {
  font-size: 1.1rem;
}

.enter-platforms {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 28px;
  flex-wrap: wrap;
}

.enter-platforms span {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 0.88rem;
  color: rgba(255,255,255,0.55);
  transition: var(--transition-fast);
}

.enter-platforms span:hover {
  color: rgba(255,255,255,0.9);
}

.enter-platforms i {
  font-size: 1.1rem;
}

/* ---------- Footer ---------- */
.footer-wrap {
  background: var(--bg-dark);
}

.footer-top {
  padding: 80px 0 60px;
  border-bottom: 1px solid rgba(255,255,255,0.06);
}

.footer-brand {
  display: inline-block;
  font-size: 1.6rem;
  font-weight: 900;
  color: white;
  margin-bottom: 16px;
  letter-spacing: -0.5px;
}

.footer-brand-desc {
  font-size: 0.9rem;
  color: rgba(255,255,255,0.5);
  line-height: 1.8;
  max-width: 280px;
  margin-bottom: 24px;
}

.footer-social {
  display: flex;
  gap: 10px;
}

.social-btn {
  width: 40px;
  height: 40px;
  border-radius: 50%;
  background: rgba(255,255,255,0.08);
  color: rgba(255,255,255,0.6);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 0.9rem;
  transition: var(--transition);
  border: 1px solid rgba(255,255,255,0.08);
}

.social-btn:hover {
  background: var(--primary);
  color: white;
  border-color: var(--primary);
  transform: translateY(-3px);
  box-shadow: 0 4px 15px rgba(102,126,234,0.4);
}

.footer-links-col {
  padding-top: 8px;
}

.footer-links-title {
  font-size: 0.9rem;
  font-weight: 700;
  color: rgba(255,255,255,0.9);
  margin-bottom: 20px;
  letter-spacing: 0.5px;
  text-transform: uppercase;
}

.footer-links {
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.footer-links a {
  font-size: 0.88rem;
  color: rgba(255,255,255,0.5);
  transition: var(--transition-fast);
  display: inline-flex;
  align-items: center;
  gap: 6px;
}

.footer-links a::before {
  content: '';
  width: 0;
  height: 1px;
  background: var(--primary);
  transition: var(--transition-fast);
}

.footer-links a:hover {
  color: white;
  padding-left: 6px;
}

.footer-links a:hover::before {
  width: 12px;
}

.footer-contact-list {
  display: flex;
  flex-direction: column;
  gap: 14px;
}

.footer-contact-list li {
  display: flex;
  align-items: center;
  gap: 12px;
  font-size: 0.88rem;
  color: rgba(255,255,255,0.5);
}

.footer-contact-list i {
  width: 18px;
  color: var(--primary);
  flex-shrink: 0;
}

.footer-contact-list a {
  color: rgba(255,255,255,0.5);
  transition: var(--transition-fast);
}

.footer-contact-list a:hover {
  color: white;
}

.footer-bottom {
  padding: 24px 0;
}

.footer-bottom-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 12px;
}

.footer-copyright,
.footer-icp {
  font-size: 0.82rem;
  color: rgba(255,255,255,0.35);
  margin: 0;
}

.footer-icp {
  display: flex;
  align-items: center;
  gap: 8px;
  flex-wrap: wrap;
}

.footer-icp a {
  color: rgba(255,255,255,0.35);
  transition: var(--transition-fast);
}

.footer-icp a:hover {
  color: rgba(255,255,255,0.7);
}

.footer-divider {
  color: rgba(255,255,255,0.15);
}

.footer-gongan {
  display: inline-flex;
  align-items: center;
  gap: 6px;
}

.footer-gongan img {
  width: 16px;
  height: 16px;
  display: inline;
  opacity: 0.5;
}

/* ---------- 回到顶部 ---------- */
.back-to-top {
  position: fixed;
  bottom: 32px;
  right: 32px;
  width: 48px;
  height: 48px;
  border-radius: 50%;
  background: var(--gradient-main);
  color: white;
  border: none;
  cursor: pointer;
  font-size: 1.1rem;
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: var(--shadow-color);
  transition: var(--transition);
  opacity: 0;
  visibility: hidden;
  transform: translateY(10px);
  z-index: 999;
}

.back-to-top.visible {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}

.back-to-top:hover {
  transform: translateY(-4px);
  box-shadow: 0 8px 25px rgba(102,126,234,0.5);
}

/* ---------- 动画 ---------- */
@keyframes fadeInDown {
  from { opacity: 0; transform: translateY(-20px); }
  to   { opacity: 1; transform: translateY(0); }
}

@keyframes fadeInUp {
  from { opacity: 0; transform: translateY(20px); }
  to   { opacity: 1; transform: translateY(0); }
}

.reveal {
  opacity: 0;
  transform: translateY(30px);
  transition: opacity 0.7s ease, transform 0.7s ease;
}

.reveal.visible {
  opacity: 1;
  transform: translateY(0);
}

/* ---------- 响应式 ---------- */

/* 平板 */
@media (max-width: 991px) {
  :root {
    --section-padding: 80px 0;
    --nav-height: 65px;
  }

  .section-title {
    font-size: 2rem;
  }

  .hero-title {
    font-size: clamp(2.2rem, 5vw, 3.5rem);
  }

  .hero-stats {
    flex-direction: column;
    gap: 20px;
    padding: 24px 32px;
  }

  .stat-divider {
    width: 60px;
    height: 1px;
  }

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

  .services-grid {
    grid-template-columns: 1fr;
  }

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

  .step-card {
    flex-direction: column;
  }

  .step-card-img {
    width: 100%;
    height: 200px;
  }

  .footer-bottom-inner {
    flex-direction: column;
    text-align: center;
  }
}

/* 手机 */
@media (max-width: 767px) {
  :root {
    --section-padding: 60px 0;
  }

  .section-title {
    font-size: 1.75rem;
  }

  .section-subtitle {
    font-size: 0.95rem;
  }

  /* 导航 */
  .ay-nav-toggle {
    display: flex;
  }

  .ay-nav-menu {
    position: fixed;
    top: var(--nav-height);
    left: 0;
    right: 0;
    background: rgba(255,255,255,0.98);
    backdrop-filter: blur(20px);
    flex-direction: column;
    align-items: stretch;
    padding: 20px;
    gap: 0;
    box-shadow: var(--shadow-lg);
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.3s ease;
  }

  .ay-nav-menu.open {
    max-height: 500px;
  }

  .nav-link {
    padding: 12px 16px;
    color: var(--text-primary);
    border-radius: var(--radius-sm);
  }

  .nav-link:hover,
  .nav-link.active {
    background: rgba(102,126,234,0.08);
    color: var(--primary);
  }

  .nav-cta {
    margin: 8px 0 0 0;
  }

  /* Hero */
  .hero-title {
    font-size: clamp(2rem, 8vw, 2.8rem);
  }

  .hero-subtitle {
    font-size: 1rem;
  }

  .hero-actions {
    flex-direction: column;
    width: 100%;
  }

  .btn-hero {
    width: 100%;
    justify-content: center;
  }

  .hero-stats {
    width: 100%;
    padding: 20px 24px;
  }

  .stat-item {
    padding: 0 16px;
  }

  .stat-num {
    font-size: 1.6rem;
  }

  /* Features */
  .features-grid {
    grid-template-columns: 1fr;
    gap: 20px;
  }

  /* Services */
  .service-card {
    flex-direction: column;
    text-align: center;
  }

  .service-icon-wrap {
    margin: 0 auto 16px;
  }

  /* Steps */
  .step-item {
    flex-direction: column;
    gap: 20px;
  }

  .step-left {
    flex-direction: row;
    width: 100%;
    align-items: center;
  }

  .step-number {
    width: 56px;
    height: 56px;
    font-size: 1.2rem;
  }

  .step-line {
    width: 100%;
    height: 2px;
    min-height: 0;
    margin: 0 12px;
  }

  .step-right {
    padding-bottom: 32px;
  }

  .step-card-img {
    height: 180px;
  }

  .step-card-content {
    padding: 24px;
  }

  .step-actions {
    flex-direction: column;
  }

  .btn-step {
    width: 100%;
    justify-content: center;
  }

  /* Screenshots */
  .screenshots-tabs {
    flex-direction: column;
    width: 100%;
  }

  .tab-btn {
    width: 100%;
    justify-content: center;
  }

  .frame-url {
    margin: 0 20px;
    font-size: 0.7rem;
  }

  /* Pricing */
  .pricing-grid {
    grid-template-columns: 1fr;
    gap: 20px;
  }

  .pricing-card-popular {
    transform: translateY(0);
  }

  .pricing-card-popular:hover {
    transform: translateY(-8px);
  }

  /* Enter */
  .enter-platforms {
    gap: 16px;
  }

  .enter-platforms span {
    font-size: 0.8rem;
  }

  /* Footer */
  .footer-top {
    padding: 60px 0 40px;
  }

  .footer-brand-col,
  .footer-links-col,
  .footer-contact-col {
    margin-bottom: 32px;
  }

  .footer-brand-desc {
    max-width: 100%;
  }

  .back-to-top {
    bottom: 20px;
    right: 20px;
    width: 44px;
    height: 44px;
  }
}

/* 超小屏 */
@media (max-width: 480px) {
  .section-title {
    font-size: 1.5rem;
  }

  .hero-badge {
    font-size: 0.8rem;
    padding: 6px 16px;
  }

  .btn-hero {
    padding: 12px 24px;font-size: 0.9rem;
  }

  .stat-item {
    padding: 0 12px;
  }

  .stat-num {
    font-size: 1.4rem;
  }

  .stat-label {
    font-size: 0.75rem;
  }

  .feature-card {
    padding: 24px 20px;
  }

  .service-card {
    padding: 24px 20px;
  }

  .step-card-content {
    padding: 20px;
  }

  .pricing-card {
    padding: 28px 20px;
  }

  .btn-enter {
    padding: 14px 32px;
    font-size: 0.95rem;
  }
}