/* ================================================================
   蜀哥乐器伴奏宝 - 官网样式表 V2.0
   视觉升级：高端大气质感、磨砂玻璃、渐变质感、悬浮动效
   主色: #1677ff (蓝) | 辅助: #ff7d00 (橙)
   ================================================================ */

/* ===== CSS 变量系统 ===== */
:root {
  --primary: #1677ff;
  --primary-dark: #0958d9;
  --primary-deep: #0f4c99;
  --primary-light: #4096ff;
  --primary-bg: #e6f4ff;
  --primary-pale: #f0f7ff;
  --logo-blue: #3c78d2;
  --logo-blue-light: #5ab4f0;
  --orange: #ff7d00;
  --orange-dark: #d65f00;
  --orange-light: #fff7e6;
  --text-dark: #1a1a2e;
  --text-body: #333333;
  --text-gray: #666666;
  --text-light: #999999;
  --bg-white: #ffffff;
  --bg-light: #f5f8fd;
  --bg-warm: #fffaf5;
  --border-light: #e8e8e8;
  --shadow-soft: 0 8px 32px rgba(0, 0, 0, 0.06);
  --shadow-card: 0 4px 20px rgba(15, 76, 153, 0.08);
  --shadow-hover: 0 12px 40px rgba(15, 76, 153, 0.15);
  --radius-sm: 8px;
  --radius-md: 12px;
  --radius-lg: 16px;
  --radius-xl: 20px;
  --max-width: 1200px;
  --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

/* ===== 全局重置 ===== */
* { margin: 0; padding: 0; box-sizing: border-box; }

html {
  scroll-behavior: smooth;
  scroll-padding-top: 80px;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC",
               "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  font-size: 18px;
  line-height: 1.7;
  color: var(--text-body);
  background: linear-gradient(180deg, #F5F8FD 0%, #ffffff 100%);
  background-attachment: fixed;
  overflow-x: hidden;
}

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

/* ===== 滚动淡入动画（全局） ===== */
.reveal {
  opacity: 0;
  transform: translateY(40px);
  transition: opacity 0.8s ease, transform 0.8s ease;
}
.reveal.visible {
  opacity: 1;
  transform: translateY(0);
}

/* ===== 柔和分割线（全局模块间） ===== */
section + section::before {
  content: '';
  display: block;
  height: 1px;
  background: linear-gradient(90deg, transparent, rgba(22,119,255,0.08), transparent);
}

/* ===== 通用容器 ===== */
.container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 24px;
  position: relative;
  z-index: 1;
}

/* ===== 通用按钮（渐变质感） ===== */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 14px 36px;
  font-size: 18px;
  font-weight: 600;
  border-radius: var(--radius-lg);
  border: none;
  cursor: pointer;
  transition: var(--transition);
  text-align: center;
  line-height: 1.5;
}
.btn:active { transform: scale(0.97); }
.btn-primary {
  background: linear-gradient(135deg, #0F4C99 0%, #3688FF 100%);
  color: #fff;
  box-shadow: 0 4px 16px rgba(15,76,153,0.35);
}
.btn-primary:hover {
  background: linear-gradient(135deg, #0d3d7a 0%, #2d7ae8 100%);
  transform: translateY(-2px);
  box-shadow: 0 6px 24px rgba(15,76,153,0.45), 0 0 20px rgba(54,136,255,0.2);
}
.btn-orange {
  background: linear-gradient(135deg, #e66e00 0%, #ff7d00 100%);
  color: #fff;
  box-shadow: 0 4px 16px rgba(255,125,0,0.35);
}
.btn-orange:hover {
  background: linear-gradient(135deg, #cc5f00 0%, #e66e00 100%);
  transform: translateY(-2px);
  box-shadow: 0 6px 24px rgba(255,125,0,0.45);
}
.btn-outline {
  background: transparent;
  color: #fff;
  border: 2px solid rgba(255,255,255,0.7);
}
.btn-outline:hover {
  background: rgba(255,255,255,0.15);
  border-color: #fff;
  transform: translateY(-2px);
}
.btn-ghost {
  background: #fff;
  color: var(--primary);
  border: 2px solid var(--primary);
}
.btn-ghost:hover {
  background: var(--primary);
  color: #fff;
  transform: translateY(-2px);
}
.btn-lg { padding: 16px 44px; font-size: 20px; }

/* ===== 通用板块标题 ===== */
.section-header { text-align: center; margin-bottom: 56px; }
.section-header .eyebrow {
  display: inline-block;
  font-size: 15px;
  font-weight: 600;
  color: var(--primary);
  background: var(--primary-bg);
  padding: 6px 18px;
  border-radius: 20px;
  margin-bottom: 16px;
  letter-spacing: 1px;
}
.section-title {
  font-size: 36px;
  font-weight: 800;
  color: var(--text-dark);
  margin-bottom: 14px;
  letter-spacing: -0.5px;
}
.section-subtitle {
  font-size: 20px;
  color: var(--text-gray);
  max-width: 600px;
  margin: 0 auto;
}

/* ===== 卡片统一样式（16px圆角+8px柔和阴影） ===== */
.card-style {
  background: #fff;
  border-radius: 16px;
  box-shadow: 0 4px 20px rgba(15, 76, 153, 0.06);
  transition: var(--transition);
}
.card-style:hover {
  transform: translateY(-1px);
  box-shadow: 0 8px 32px rgba(15, 76, 153, 0.12);
}

/* ===== 手机框组件 ===== */
.phone-frame {
  position: relative;
  border-radius: 28px;
  background: #1a1a1a;
  padding: 10px;
  box-shadow: 0 16px 60px rgba(0, 0, 0, 0.18), 0 0 0 1px rgba(255,255,255,0.05) inset;
  transition: transform 0.3s ease;
}
.phone-frame:hover { transform: translateY(-4px); }
.phone-frame img {
  width: 100%;
  border-radius: 20px;
  display: block;
}
.phone-frame::before {
  content: '';
  position: absolute;
  top: 10px; left: 50%;
  transform: translateX(-50%);
  width: 90px; height: 22px;
  background: #1a1a1a;
  border-radius: 0 0 14px 14px;
  z-index: 2;
}

/* ================================================================
   模块1: 顶部固定导航栏（磨砂玻璃效果）
   ================================================================ */
.navbar {
  position: fixed;
  top: 0; left: 0; width: 100%;
  height: 72px;
  background: rgba(255, 255, 255, 0.72);
  backdrop-filter: blur(20px) saturate(180%);
  -webkit-backdrop-filter: blur(20px) saturate(180%);
  box-shadow: 0 1px 12px rgba(0, 0, 0, 0.04);
  z-index: 1000;
  display: flex;
  align-items: center;
  transition: var(--transition);
}
.navbar.scrolled {
  background: rgba(255, 255, 255, 0.95);
  box-shadow: 0 2px 24px rgba(0, 0, 0, 0.1);
}
.navbar .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  width: 100%;
}
.navbar-brand {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 22px;
  font-weight: 800;
  color: var(--primary);
  white-space: nowrap;
}
.navbar-brand .brand-logo {
  width: 40px; height: 40px;
  border-radius: 10px;
  object-fit: cover;
  flex-shrink: 0;
  box-shadow: 0 2px 8px rgba(22, 119, 255, 0.15);
}
.navbar-menu {
  display: flex;
  gap: 36px;
}
.navbar-menu li a {
  font-size: 17px;
  color: var(--text-body);
  font-weight: 500;
  position: relative;
  padding: 6px 0;
  transition: color 0.2s;
}
.navbar-menu li a::after {
  content: '';
  position: absolute;
  bottom: -2px; left: 0;
  width: 0; height: 2px;
  background: linear-gradient(90deg, var(--primary), var(--primary-light));
  border-radius: 2px;
  transition: width 0.25s ease;
}
.navbar-menu li a:hover { color: var(--primary); }
.navbar-menu li a:hover::after,
.navbar-menu li a.active::after { width: 100%; }
.navbar-download {
  background: linear-gradient(135deg, #e66e00 0%, #ff7d00 100%);
  color: #fff !important;
  padding: 10px 24px;
  border-radius: 10px;
  font-size: 16px;
  font-weight: 600;
  white-space: nowrap;
  box-shadow: 0 3px 12px rgba(255,125,0,0.3);
  transition: var(--transition);
}
.navbar-download::after { display: none !important; }
.navbar-download:hover {
  background: linear-gradient(135deg, #cc5f00 0%, #e66e00 100%);
  transform: translateY(-1px);
  box-shadow: 0 5px 16px rgba(255,125,0,0.4);
}
.navbar-toggle {
  display: none;
  font-size: 26px;
  background: none; border: none;
  color: var(--text-dark);
  cursor: pointer;
  padding: 4px 8px;
}

/* ================================================================
   模块2: 首屏Banner（深蓝到浅蓝垂直渐变 + 柔和音波装饰）
   适配中老年视觉：低饱和、不刺眼、简约高级
   ================================================================ */
.banner {
  position: relative;
  min-height: 680px;
  display: flex;
  align-items: center;
  padding-top: 72px;
  background:
    linear-gradient(180deg,
      #0a1628 0%,
      #0d1f3c 10%,
      #123a6d 25%,
      #1a5f9e 45%,
      #2a7cc8 65%,
      #4a9fe0 80%,
      #7bb8ec 90%,
      #a8d0f0 100%
    );
  overflow: hidden;
}
/* ===== 柔和音波背景层 ===== */
.banner-wave-bg {
  position: absolute;
  top: 0; left: 0; right: 0; bottom: 0;
  pointer-events: none;
  z-index: 0;
  overflow: hidden;
}
/* SVG 音波曲线 - 极柔和 */
.banner-wave-bg .wave-svg {
  position: absolute;
  left: 0; right: 0;
  width: 100%;
  filter: blur(8px);
  opacity: 0.6;
}
.banner-wave-bg .wave-svg path {
  fill: rgba(200,230,255,0.15);
}
/* 音波高度与动画 */
.banner-wave-bg .wave-1 {
  bottom: 15%;
  height: 220px;
  animation: waveDrift 12s ease-in-out infinite;
}
.banner-wave-bg .wave-2 {
  bottom: 25%;
  height: 180px;
  animation: waveDrift 15s ease-in-out infinite reverse;
  opacity: 0.4;
}
.banner-wave-bg .wave-3 {
  bottom: 5%;
  height: 260px;
  animation: waveDrift 18s ease-in-out infinite;
  opacity: 0.3;
}
/* 柔和水平光带 */
.banner-light-stripe {
  position: absolute;
  top: 55%;
  left: -10%; right: -10%;
  height: 120px;
  background: linear-gradient(
    180deg,
    transparent 0%,
    rgba(150,210,255,0.04) 30%,
    rgba(180,225,255,0.08) 50%,
    rgba(150,210,255,0.04) 70%,
    transparent 100%
  );
  filter: blur(40px);
  pointer-events: none;
  animation: lightPulse 8s ease-in-out infinite;
}

@keyframes waveDrift {
  0%, 100% { transform: translateX(0) scaleY(1); }
  33% { transform: translateX(-20px) scaleY(1.05); }
  66% { transform: translateX(15px) scaleY(0.95); }
}
@keyframes lightPulse {
  0%, 100% { opacity: 0.6; }
  50% { opacity: 1; }
}
/* 简约暗纹点阵 */
.banner-note-pattern {
  position: absolute;
  top: 0; left: 0; right: 0; bottom: 0;
  background-image:
    radial-gradient(circle at 15% 30%, rgba(255,255,255,0.02) 2px, transparent 2px),
    radial-gradient(circle at 75% 70%, rgba(255,255,255,0.015) 1.5px, transparent 1.5px),
    radial-gradient(circle at 50% 50%, rgba(255,255,255,0.01) 3px, transparent 3px);
  background-size: 180px 180px, 240px 240px, 120px 120px;
  pointer-events: none;
  z-index: 1;
}
/* 装饰光晕 */
.banner-deco-1 {
  position: absolute;
  bottom: -120px; left: -80px;
  width: 400px; height: 400px;
  background: radial-gradient(circle, rgba(100,180,255,0.08) 0%, transparent 60%);
  border-radius: 50%;
  pointer-events: none;
  z-index: 0;
}
.banner-deco-2 {
  position: absolute;
  top: 20%; right: 15%;
  width: 300px; height: 300px;
  background: radial-gradient(circle, rgba(255,255,255,0.04) 0%, transparent 60%);
  border-radius: 50%;
  pointer-events: none;
  z-index: 0;
}
.banner .container {
  position: relative;
  z-index: 2;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 40px;
}
.banner-content {
  flex: 1;
  color: #fff;
  max-width: 560px;
}
.banner-content h1 {
  font-size: 44px;
  font-weight: 800;
  line-height: 1.3;
  margin-bottom: 20px;
  letter-spacing: -1px;
  text-shadow: 0 2px 16px rgba(0,0,0,0.2), 0 4px 32px rgba(0,0,0,0.1);
}
.banner-subtitle {
  font-size: 20px;
  line-height: 1.8;
  margin-bottom: 24px;
  opacity: 0.95;
}
/* 信任小字 */
.banner-trust {
  font-size: 15px;
  opacity: 0.8;
  margin-bottom: 24px;
  display: flex;
  align-items: center;
  gap: 8px;
}
.banner-trust .star { color: #ffd700; }
/* 胶囊标签样式 */
.banner-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-bottom: 36px;
}
.banner-tags .tag {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  background: rgba(255,255,255,0.15);
  backdrop-filter: blur(10px);
  border: 1px solid rgba(255,255,255,0.2);
  padding: 8px 20px;
  border-radius: 30px;
  font-size: 15px;
  font-weight: 500;
  color: #fff;
}
.banner-tags .tag .check { font-size: 16px; }
.banner-buttons {
  display: flex;
  gap: 20px;
  flex-wrap: wrap;
}
/* Banner右侧手机 */
.banner-phone {
  flex-shrink: 0;
  position: relative;
}
.banner-phone .phone-frame {
  width: 280px;
  animation: floatUp 4s ease-in-out infinite;
}
@keyframes floatUp {
  0%, 100% { transform: translateY(0); }
  50% { transform: translateY(-16px); }
}
.banner-phone .float-badge {
  position: absolute;
  background: rgba(255, 255, 255, 0.95);
  border-radius: 12px;
  padding: 10px 16px;
  font-size: 14px;
  font-weight: 700;
  color: var(--text-dark);
  box-shadow: var(--shadow-soft);
  white-space: nowrap;
  z-index: 3;
}
.banner-phone .float-badge.badge-1 {
  top: 20%; left: -60px;
  color: var(--primary);
  animation: floatSide 5s ease-in-out infinite;
}
.banner-phone .float-badge.badge-2 {
  bottom: 25%; right: -50px;
  color: var(--orange);
  animation: floatSide 5s ease-in-out infinite 1.5s;
}
@keyframes floatSide {
  0%, 100% { transform: translateX(0); }
  50% { transform: translateX(10px); }
}

/* ================================================================
   模块3: 四大核心卖点卡片（16px圆角+8px柔和阴影+悬浮动效）
   ================================================================ */
.features {
  padding: 100px 0;
  background: linear-gradient(180deg, #F5F8FD 0%, #f8fbff 50%, #F5F8FD 100%);
  position: relative;
}
.features-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
}
.feature-card {
  background: #fff;
  border-radius: 16px;
  padding: 40px 28px;
  text-align: center;
  box-shadow: 0 4px 20px rgba(15, 76, 153, 0.06);
  transition: var(--transition);
  border: 2px solid transparent;
  position: relative;
  overflow: hidden;
}
.feature-card::before {
  content: '';
  position: absolute;
  top: 0; left: 0; right: 0;
  height: 4px;
  background: linear-gradient(90deg, var(--primary-deep), var(--primary-light));
  transform: scaleX(0);
  transition: transform 0.3s ease;
}
.feature-card:hover {
  transform: translateY(-1px);
  box-shadow: 0 8px 32px rgba(15, 76, 153, 0.12);
}
.feature-card:hover::before { transform: scaleX(1); }
.feature-card.highlight {
  border-color: var(--orange);
}
.feature-card.highlight::before {
  background: linear-gradient(90deg, var(--orange-dark), var(--orange));
}
.feature-card.highlight .feature-icon {
  background: var(--orange-light) !important;
}
.feature-icon {
  width: 76px; height: 76px;
  margin: 0 auto 24px;
  border-radius: 20px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 34px;
}
.feature-icon.icon-1 { background: var(--primary-bg); }
.feature-icon.icon-2 { background: var(--orange-light); }
.feature-icon.icon-3 { background: #f6ffed; }
.feature-icon.icon-4 { background: var(--orange-light); }
.feature-card h3 {
  font-size: 22px;
  font-weight: 700;
  margin-bottom: 14px;
  color: var(--text-dark);
}
.feature-card.highlight h3 { color: var(--orange); }
.feature-card p {
  font-size: 16px;
  color: var(--text-gray);
  line-height: 1.85;
}
.feature-card .card-badge {
  position: absolute;
  top: 16px; right: -32px;
  background: linear-gradient(135deg, var(--orange), #ff9933);
  color: #fff;
  font-size: 13px;
  font-weight: 600;
  padding: 4px 36px;
  transform: rotate(45deg);
}

/* ================================================================
   模块4: 功能图文展示区（截图12px圆角+投影+关键词高亮）
   丰富版：核心播放 | 智能工具 | 曲谱与曲库 | 个性化管理
   ================================================================ */
.showcase {
  padding: 100px 0;
  background: linear-gradient(180deg, #ffffff 0%, #fafcfd 50%, #ffffff 100%);
  position: relative;
}

/* 功能分组 */
.showcase-group {
  margin-bottom: 80px;
  position: relative;
}
.showcase-group:last-child {
  margin-bottom: 0;
}

/* 分组标签（玻璃拟态胶囊） */
.group-label {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  background: linear-gradient(135deg, rgba(22,119,255,0.08) 0%, rgba(92,180,240,0.1) 100%);
  border: 1px solid rgba(22,119,255,0.12);
  padding: 8px 24px;
  border-radius: 50px;
  font-size: 14px;
  font-weight: 700;
  color: var(--primary);
  letter-spacing: 1px;
  text-transform: uppercase;
  margin-bottom: 36px;
  backdrop-filter: blur(10px);
}
.group-label::before {
  content: '';
  width: 6px; height: 6px;
  border-radius: 50%;
  background: var(--primary);
  display: inline-block;
}

/* 功能条目 - 交替排列 */
.showcase-item {
  display: flex;
  align-items: center;
  gap: 64px;
  margin-bottom: 80px;
  position: relative;
}
.showcase-item:last-child { margin-bottom: 0; }
.showcase-item:nth-child(even) { flex-direction: row-reverse; }
.showcase-item:nth-child(even) .showcase-text { text-align: right; }
.showcase-item:nth-child(even) .showcase-text .showcase-detail-list .detail-item { flex-direction: row-reverse; text-align: right; }
.showcase-item:nth-child(even) .showcase-text .showcase-detail-list .detail-item > div { text-align: right; }

/* 视觉区 - 双图叠放 */
.showcase-visual {
  flex: 0 0 380px;
  display: flex;
  justify-content: center;
  align-items: center;
  position: relative;
  min-height: 480px;
}
.showcase-visual .phone-frame {
  width: 300px;
  border-radius: 24px;
  position: relative;
  z-index: 1;
  transition: var(--transition);
}
/* 第二张手机框叠放效果 */
.showcase-visual .phone-frame-secondary {
  position: absolute;
  width: 260px;
  z-index: 0;
  opacity: 0.7;
  transform: translate(-80px, 40px) rotate(-8deg);
  box-shadow: 0 8px 24px rgba(0,0,0,0.08);
}
/* 右侧布局时第二张图在另一侧 */
.showcase-item:nth-child(even) .phone-frame-secondary {
  transform: translate(80px, 40px) rotate(8deg);
}
.showcase-item:hover .phone-frame {
  transform: translateY(-4px);
  box-shadow: 0 12px 32px rgba(0,0,0,0.15);
}
.showcase-item:hover .phone-frame-secondary {
  transform: translate(-80px, 30px) rotate(-6deg);
  opacity: 0.85;
}
.showcase-item:nth-child(even):hover .phone-frame-secondary {
  transform: translate(80px, 30px) rotate(6deg);
}

/* 截图圆角+投影 */
.showcase-visual .phone-frame img {
  border-radius: 18px;
  box-shadow: 0 8px 24px rgba(0, 0, 0, 0.12);
  width: 100%;
  display: block;
}

/* 背景光晕装饰 */
.showcase-visual::before {
  content: '';
  position: absolute;
  top: 50%; left: 50%;
  transform: translate(-50%, -50%);
  width: 400px; height: 400px;
  background: radial-gradient(circle, var(--primary-bg) 0%, transparent 70%);
  border-radius: 50%;
  z-index: 0;
  opacity: 0.6;
}

/* 文字区 */
.showcase-text { flex: 1; min-width: 0; }
.showcase-text .step-num {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 44px; height: 44px;
  background: linear-gradient(135deg, var(--primary-deep), var(--primary));
  color: #fff;
  border-radius: 50%;
  font-size: 18px;
  font-weight: 800;
  margin-bottom: 16px;
  box-shadow: 0 4px 12px rgba(22,119,255,0.3);
}
.showcase-text h3 {
  font-size: 30px;
  font-weight: 800;
  color: var(--text-dark);
  margin-bottom: 18px;
  display: flex;
  align-items: center;
  gap: 12px;
}
.showcase-text h3 .badge-new {
  display: inline-flex;
  align-items: center;
  padding: 4px 12px;
  background: linear-gradient(135deg, var(--orange), #ff9933);
  color: #fff;
  font-size: 13px;
  font-weight: 700;
  border-radius: 20px;
  letter-spacing: 1px;
}
.showcase-text .showcase-desc {
  font-size: 18px;
  color: var(--text-gray);
  line-height: 1.9;
  margin-bottom: 24px;
}
.showcase-text .showcase-desc .highlight-blue {
  color: var(--primary);
  font-weight: 700;
}

/* 详细功能列表 */
.showcase-detail-list {
  display: flex;
  flex-direction: column;
  gap: 14px;
  margin-bottom: 24px;
}
.detail-item {
  display: flex;
  align-items: flex-start;
  gap: 14px;
  padding: 12px 16px;
  background: linear-gradient(135deg, #ffffff 0%, #f8fbff 100%);
  border-radius: 12px;
  border: 1px solid rgba(22,119,255,0.06);
  transition: var(--transition);
}
.detail-item:hover {
  transform: translateX(4px);
  border-color: rgba(22,119,255,0.15);
  box-shadow: 0 4px 12px rgba(22,119,255,0.08);
}
.showcase-item:nth-child(even) .detail-item:hover {
  transform: translateX(-4px);
}
.detail-item .detail-icon {
  width: 36px; height: 36px;
  min-width: 36px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: linear-gradient(135deg, var(--primary-bg) 0%, #e8f2ff 100%);
  border-radius: 10px;
  font-size: 18px;
}
.detail-item > div {
  display: flex;
  flex-direction: column;
  gap: 2px;
}
.detail-item > div strong {
  font-size: 16px;
  color: var(--text-dark);
  font-weight: 700;
}
.detail-item > div span {
  font-size: 14px;
  color: var(--text-light);
  line-height: 1.6;
}

/* 关键词标签 */
.showcase-text .feature-points {
  margin-top: 20px;
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}
.showcase-text .feature-points span {
  background: linear-gradient(135deg, var(--primary-bg) 0%, #e8f2ff 100%);
  color: var(--primary);
  font-size: 14px;
  font-weight: 600;
  padding: 6px 14px;
  border-radius: 8px;
  border: 1px solid rgba(22,119,255,0.08);
}

/* 数字提炼短句 - 移除旧版 */
.showcase-text .short-summary { display: none; }

/* ================================================================
   模块5: 曲库数据可视化（浅蓝渐变卡片+数字放大品牌蓝）
   ================================================================ */
.stats {
  padding: 100px 0;
  background: linear-gradient(180deg, #e8f2ff 0%, #f0f7ff 40%, #f5faff 100%);
  position: relative;
}
.stats-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
  margin-bottom: 56px;
}
.stat-card {
  text-align: center;
  background: linear-gradient(180deg, #ffffff 0%, #f5faff 100%);
  border-radius: 16px;
  padding: 48px 20px;
  box-shadow: 0 4px 20px rgba(15, 76, 153, 0.06);
  transition: var(--transition);
  border: 1px solid rgba(22, 119, 255, 0.06);
}
.stat-card:hover {
  transform: translateY(-1px);
  box-shadow: 0 8px 32px rgba(15, 76, 153, 0.12);
}
.stat-number {
  font-size: 48px;
  font-weight: 800;
  background: linear-gradient(135deg, var(--primary-deep), var(--primary-light));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  line-height: 1.2;
}
.stat-label {
  font-size: 16px;
  color: var(--text-light);
  margin-top: 12px;
  line-height: 1.6;
}
.stats-tags-title {
  text-align: center;
  font-size: 20px;
  font-weight: 700;
  color: var(--text-dark);
  margin-bottom: 24px;
}
.stats-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 14px;
  justify-content: center;
}
.stats-tag {
  padding: 10px 24px;
  background: #fff;
  border: 1px solid var(--border-light);
  border-radius: 30px;
  font-size: 15px;
  color: var(--text-gray);
  transition: var(--transition);
  cursor: default;
}
.stats-tag:hover {
  background: linear-gradient(135deg, var(--primary) 0%, var(--primary-light) 100%);
  color: #fff;
  border-color: var(--primary);
  transform: translateY(-2px);
  box-shadow: 0 4px 12px rgba(22,119,255,0.25);
}

/* ================================================================
   模块6: 使用场景
   ================================================================ */
.scenarios {
  padding: 100px 0;
  background:
    radial-gradient(circle at 20% 30%, rgba(22, 119, 255, 0.03) 0%, transparent 50%),
    radial-gradient(circle at 80% 70%, rgba(255, 125, 0, 0.02) 0%, transparent 50%),
    linear-gradient(180deg, #ffffff 0%, #f8fbff 100%);
}
.scenarios-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
}
.scenario-card {
  text-align: center;
  padding: 44px 24px;
  border-radius: 16px;
  background: linear-gradient(180deg, #f8fbff 0%, #ffffff 100%);
  border: 1px solid rgba(22, 119, 255, 0.08);
  box-shadow: 0 4px 20px rgba(15, 76, 153, 0.04);
  transition: var(--transition);
}
.scenario-card:hover {
  transform: translateY(-1px);
  box-shadow: 0 8px 32px rgba(15, 76, 153, 0.1);
  border-color: rgba(22, 119, 255, 0.15);
}
.scenario-icon {
  width: 72px; height: 72px;
  margin: 0 auto 20px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--primary-bg) 0%, #f0f7ff 100%);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 36px;
}
.scenario-card h3 {
  font-size: 22px;
  font-weight: 700;
  color: var(--text-dark);
  margin-bottom: 10px;
}
.scenario-card p {
  font-size: 16px;
  color: var(--text-gray);
}

/* 场景大图 */
.scene-hero {
  margin-bottom: 64px;
  border-radius: 16px;
  overflow: hidden;
  box-shadow: 0 12px 40px rgba(0, 0, 0, 0.12);
  background: #fff;
  border: 1px solid rgba(0,0,0,0.04);
}
.scene-hero img {
  width: 100%;
  height: auto;
  display: block;
}
.scene-hero .scene-caption {
  text-align: center;
  font-size: 17px;
  color: var(--text-gray);
  padding: 16px 24px;
  background: linear-gradient(180deg, #fafbfd 0%, #f5f8fd 100%);
  border-top: 1px solid var(--border-light);
}

/* ================================================================
   模块7: FAQ折叠问答（浅渐变底色+上下箭头+展开高亮）
   ================================================================ */
.faq {
  padding: 100px 0;
  background: linear-gradient(180deg, #f5f8fd 0%, #eef3fa 50%, #f5f8fd 100%);
  position: relative;
}
.faq-list { max-width: 820px; margin: 0 auto; }
.faq-item {
  background: linear-gradient(180deg, #ffffff 0%, #fafcfe 100%);
  border-radius: 16px;
  margin-bottom: 16px;
  overflow: hidden;
  box-shadow: 0 2px 12px rgba(15, 76, 153, 0.04);
  transition: var(--transition);
  border: 1px solid rgba(0,0,0,0.03);
}
.faq-item:hover {
  box-shadow: 0 4px 20px rgba(15, 76, 153, 0.08);
}
.faq-item.active {
  box-shadow: 0 6px 24px rgba(15, 76, 153, 0.1);
  border-color: rgba(22, 119, 255, 0.1);
}
.faq-question {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 22px 28px;
  cursor: pointer;
  font-size: 19px;
  font-weight: 600;
  color: var(--text-dark);
  user-select: none;
  transition: background 0.2s;
}
.faq-question:hover { background: rgba(22, 119, 255, 0.02); }
.faq-question .faq-icon {
  font-size: 14px;
  color: var(--primary);
  transition: transform 0.3s ease;
  flex-shrink: 0;
  margin-left: 16px;
  width: 32px;
  height: 32px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: 50%;
  background: var(--primary-bg);
  font-weight: 700;
}
/* 展开状态：标题变蓝 */
.faq-item.active .faq-question {
  color: var(--primary);
  background: linear-gradient(90deg, rgba(22,119,255,0.04), transparent);
}
.faq-item.active .faq-icon {
  transform: rotate(180deg);
  background: var(--primary);
  color: #fff;
}
.faq-answer {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.35s ease;
}
.faq-answer-inner {
  padding: 0 28px 24px;
  font-size: 18px;
  color: var(--text-gray);
  line-height: 1.9;
}
/* FAQ答案内高亮关键词 */
.faq-answer-inner .hl {
  color: var(--primary);
  font-weight: 600;
}

/* ================================================================
   模块8: 底部下载购买转化区（首尾呼应+点击反馈+二维码边框）
   ================================================================ */
.download {
  padding: 100px 0;
  background:
    radial-gradient(ellipse at 30% 20%, rgba(54, 136, 255, 0.1) 0%, transparent 50%),
    radial-gradient(ellipse at 70% 80%, rgba(255, 125, 0, 0.06) 0%, transparent 50%),
    linear-gradient(160deg, #05285f 0%, #0a3d91 35%, #1677ff 60%, #3c78d2 100%);
  text-align: center;
  color: #fff;
  position: relative;
  overflow: hidden;
}
/* 和首屏Banner首尾呼应的音符暗纹 */
.download-note-pattern {
  position: absolute;
  top: 0; left: 0; right: 0; bottom: 0;
  background-image:
    radial-gradient(circle at 20% 40%, rgba(255,255,255,0.03) 2px, transparent 2px),
    radial-gradient(circle at 60% 70%, rgba(255,255,255,0.02) 1.5px, transparent 1.5px);
  background-size: 150px 150px, 200px 200px;
  pointer-events: none;
  z-index: 1;
}
.download-deco {
  position: absolute;
  top: 30%; left: 10%;
  width: 250px; height: 250px;
  background: radial-gradient(circle, rgba(255,255,255,0.04) 0%, transparent 60%);
  border-radius: 50%;
  pointer-events: none;
}
.download .container { position: relative; z-index: 2; }
.download h2 {
  font-size: 36px;
  font-weight: 800;
  margin-bottom: 18px;
  text-shadow: 0 2px 12px rgba(0,0,0,0.15);
}
/* 加粗醒目文字 */
.download .download-highlight {
  font-size: 20px;
  font-weight: 700;
  margin-bottom: 12px;
  background: linear-gradient(90deg, #fff, #ffd699);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}
.download-desc {
  font-size: 18px;
  opacity: 0.92;
  margin-bottom: 44px;
}
.download-buttons {
  display: flex;
  gap: 24px;
  justify-content: center;
  flex-wrap: wrap;
  margin-bottom: 52px;
}
/* 下载按钮点击缩放反馈 */
.download-btn {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 18px 36px;
  border-radius: 16px;
  font-size: 19px;
  font-weight: 700;
  min-width: 220px;
  transition: var(--transition);
}
.download-btn:active { transform: scale(0.95); }
.download-btn:hover { transform: translateY(-3px); }
.download-btn.android {
  background: linear-gradient(135deg, #e66e00 0%, #ff7d00 100%);
  color: #fff;
  box-shadow: 0 6px 20px rgba(255,125,0,0.35);
}
.download-btn.android:hover {
  background: linear-gradient(135deg, #cc5f00 0%, #e66e00 100%);
  box-shadow: 0 8px 28px rgba(255,125,0,0.45);
}
.download-btn.ios {
  background: #fff;
  color: var(--primary);
  box-shadow: 0 6px 20px rgba(0,0,0,0.15);
}
.download-btn.ios:hover {
  background: var(--primary-bg);
  box-shadow: 0 8px 28px rgba(0,0,0,0.2);
}
.download-btn .btn-icon { font-size: 28px; }
.download-btn .btn-text { text-align: left; line-height: 1.3; }
.download-btn .btn-text small { font-size: 13px; font-weight: 400; opacity: 0.8; display: block; }

/* 双二维码并排区域（10px圆角浅蓝边框） */
.qrcode-row {
  display: flex;
  justify-content: center;
  gap: 32px;
  flex-wrap: wrap;
}
.qr-card {
  background: rgba(255, 255, 255, 0.12);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  border: 1px solid rgba(255,255,255,0.15);
  border-radius: 16px;
  padding: 36px 28px;
  display: inline-block;
  width: 280px;
  transition: var(--transition);
}
.qr-card:hover {
  transform: translateY(-4px);
  background: rgba(255, 255, 255, 0.18);
}
.qr-card h4 { font-size: 20px; margin-bottom: 18px; }
.qr-card .qr-box {
  width: 200px; height: 200px;
  background: #fff;
  border-radius: 10px;
  margin: 0 auto 14px;
  overflow: hidden;
  border: 3px solid var(--primary-bg);
  box-shadow: 0 4px 12px rgba(0,0,0,0.1);
  transition: var(--transition);
}
.qr-card:hover .qr-box {
  border-color: var(--primary-light);
  box-shadow: 0 6px 20px rgba(22,119,255,0.15);
}
.qr-card .qr-box img { width: 100%; height: 100%; object-fit: cover; }
.qr-card p { font-size: 16px; opacity: 0.9; }
.qr-card p strong { font-weight: 700; opacity: 1; }

/* ================================================================
   模块9: 页脚
   ================================================================ */
.footer {
  background: linear-gradient(180deg, #0a1628 0%, #111827 100%);
  color: #8b949e;
  text-align: center;
  padding: 44px 24px;
  position: relative;
}
.footer::before {
  content: '';
  position: absolute;
  top: 0; left: 0; right: 0;
  height: 1px;
  background: linear-gradient(90deg, transparent 10%, rgba(22,119,255,0.2) 50%, transparent 90%);
}
.footer p { font-size: 16px; margin: 6px 0; }
.footer .footer-note { font-size: 14px; color: #6e7681; margin-top: 8px; }
.footer .footer-seo { font-size: 12px; color: #4a5260; margin-top: 12px; line-height: 1.8; max-width: 800px; margin-left: auto; margin-right: auto; }

/* ================================================================
   响应式: 平板（≤992px）
   ================================================================ */
@media (max-width: 992px) {
  .features-grid { grid-template-columns: repeat(2, 1fr); }
  .stats-grid { grid-template-columns: repeat(2, 1fr); }
  .scenarios-grid { grid-template-columns: repeat(2, 1fr); }
  .banner-content h1 { font-size: 36px; }
  .banner .container { flex-direction: column; text-align: center; }
  .banner-content { max-width: 100%; }
  .banner-tags { justify-content: center; }
  .banner-buttons { justify-content: center; }
  .banner-phone { margin-top: 20px; }
  .banner-phone .phone-frame { width: 240px; }
  .banner-phone .float-badge { display: none; }
  .section-title { font-size: 30px; }
  .showcase-item { gap: 40px; }
  .showcase-visual { flex-basis: 300px; min-height: 400px; }
  .showcase-visual .phone-frame { width: 260px; }
  .showcase-visual .phone-frame-secondary { width: 220px; transform: translate(-60px, 30px) rotate(-6deg); }
  .showcase-item:nth-child(even) .phone-frame-secondary { transform: translate(60px, 30px) rotate(6deg); }
}

/* ================================================================
   响应式: 手机（≤768px）
   ================================================================ */
@media (max-width: 768px) {
  body { font-size: 17px; }

  /* 导航栏 */
  .navbar-menu {
    display: none;
    position: absolute;
    top: 72px; left: 0; width: 100%;
    background: rgba(255,255,255,0.98);
    backdrop-filter: blur(20px);
    flex-direction: column;
    gap: 0;
    padding: 8px 0;
    box-shadow: 0 4px 16px rgba(0, 0, 0, 0.1);
  }
  .navbar-menu.show { display: flex; }
  .navbar-menu li { width: 100%; text-align: center; }
  .navbar-menu li a {
    display: block;
    padding: 15px 20px;
    font-size: 18px;
    border-bottom: 1px solid var(--border-light);
  }
  .navbar-menu li:last-child a { border-bottom: none; }
  .navbar-toggle { display: block; }
  .navbar-download { display: none; }
  .navbar-menu.show .navbar-download {
    display: inline-block;
    margin: 12px auto;
  }

  /* Banner */
  .banner { min-height: auto; padding: 100px 0 60px; }
  .banner-content h1 { font-size: 28px; }
  .banner-subtitle { font-size: 17px; }
  .banner-tags .tag { font-size: 14px; padding: 6px 14px; }
  .banner-trust { font-size: 13px; justify-content: center; }
  .banner-buttons { flex-direction: column; gap: 14px; }
  .banner-buttons .btn { width: 100%; }
  .banner-phone { margin-top: 30px; }
  .banner-phone .phone-frame { width: 220px; }

  /* 卖点卡片 */
  .features-grid { grid-template-columns: 1fr; }
  .feature-card { padding: 32px 24px; border-radius: 14px; }

  /* 功能展示 */
  .showcase-group { margin-bottom: 56px; }
  .group-label { font-size: 12px; padding: 6px 16px; margin-bottom: 24px; }
  .showcase-item,
  .showcase-item:nth-child(even) {
    flex-direction: column;
    gap: 28px;
    text-align: center;
    margin-bottom: 56px;
  }
  .showcase-item:nth-child(even) .showcase-text { text-align: center; }
  .showcase-item:nth-child(even) .showcase-text .showcase-detail-list .detail-item { flex-direction: row; text-align: left; }
  .showcase-item:nth-child(even) .showcase-text .showcase-detail-list .detail-item > div { text-align: left; }
  .showcase-visual { flex-basis: auto; min-height: auto; }
  .showcase-visual .phone-frame { width: 240px; }
  .showcase-visual .phone-frame-secondary { display: none; }
  .showcase-visual::before { width: 300px; height: 300px; }
  .showcase-text h3 { font-size: 24px; justify-content: center; }
  .showcase-text .showcase-desc { font-size: 16px; }
  .showcase-detail-list { gap: 10px; }
  .detail-item { padding: 10px 12px; }
  .detail-item:hover { transform: none; }
  .showcase-item:nth-child(even) .detail-item:hover { transform: none; }
  .detail-item > div strong { font-size: 15px; }
  .detail-item > div span { font-size: 13px; }
  .showcase-text .feature-points { justify-content: center; }

  /* 数据 */
  .stats-grid { grid-template-columns: repeat(2, 1fr); gap: 16px; }
  .stat-number { font-size: 36px; }

  /* 场景 */
  .scenarios-grid { grid-template-columns: 1fr; gap: 16px; }
  .scenario-card { border-radius: 14px; }
  .scene-hero { border-radius: 12px; margin-bottom: 40px; }
  .scene-hero .scene-caption { font-size: 15px; padding: 12px 16px; }

  /* FAQ */
  .faq-question { font-size: 17px; padding: 18px 20px; }
  .faq-answer-inner { font-size: 16px; padding: 0 20px 18px; }
  .faq-item { border-radius: 14px; }

  /* 下载 */
  .download h2 { font-size: 27px; }
  .download .download-highlight { font-size: 17px; }
  .download-desc { font-size: 16px; }
  .download-buttons { flex-direction: column; gap: 16px; align-items: center; }
  .download-btn { width: 100%; max-width: 320px; }
  .qrcode-row { flex-direction: column; gap: 20px; align-items: center; }
  .qr-card { width: 100%; max-width: 320px; }

  /* 通用 */
  .section-title { font-size: 25px; }
  .section-subtitle { font-size: 16px; }
  .section-header { margin-bottom: 36px; }
  .features, .showcase, .stats, .scenarios, .faq { padding: 60px 0; }
  .download { padding: 60px 0; }
}

/* 超小屏（≤400px） */
@media (max-width: 400px) {
  .stats-grid { grid-template-columns: 1fr; }
  .banner-content h1 { font-size: 24px; }
  .navbar-brand { font-size: 18px; }
  .navbar-brand .brand-logo { width: 32px; height: 32px; }
}