/* ============================================================
   乐赏帮 - 官方网站样式表
   域名：sqzxedu.com
   说明：纯手写CSS，无框架。
         布局基准宽度 1200px 居中；
         屏宽 <= 1440px 时容器固定1200px，两侧留白；
         屏宽 > 1440px 时通过 CSS clamp() 对字号、间距等比例放大；
         移动端使用媒体查询改为流式布局。
   ============================================================ */

/* ---------- 一、变量与重置 ---------- */
:root {
  /* 主题色 */
  --c-primary:        #ff9800;   /* 主色：暖橙 */
  --c-primary-deep:   #f57c00;   /* 深橙（按钮按下） */
  --c-primary-light:  #ffe0b2;   /* 浅橙（装饰背景） */
  --c-accent:         #ff3d00;   /* 强调红（优惠价等） */
  --c-success:        #43a047;   /* 成功绿 */

  /* 文字色 */
  --c-text:           #2a2a2a;   /* 主文字 */
  --c-text-2:         #555;      /* 次级文字 */
  --c-text-3:         #888;      /* 次级灰 */
  --c-muted:          #aaa;      /* 弱化 */
  --c-white:          #fff;

  /* 背景色 */
  --c-bg:             #fffdf8;   /* 页面背景（米白） */
  --c-bg-gray:        #f7f8fa;   /* 区块间隔灰 */
  --c-bg-hero:        linear-gradient(135deg, #fff6e0 0%, #ffe7c2 60%, #ffd39b 100%);
  --c-bg-cta:         linear-gradient(135deg, #ffb347 0%, #ff8a00 100%);

  /* 边框 */
  --c-border:         #eceef1;
  --c-border-2:       #e4e6eb;

  /* 阴影 */
  --sh-sm:  0 2px 8px  rgba(0,0,0,0.05);
  --sh-md:  0 8px 24px rgba(0,0,0,0.08);
  --sh-lg:  0 16px 40px rgba(255,152,0,0.18);
  --sh-hover: 0 12px 32px rgba(255,152,0,0.28);

  /* 圆角 */
  --r-sm: 6px;
  --r-md: 12px;
  --r-lg: 20px;
  --r-xl: 28px;

  /* 字体 */
  --f-base: -apple-system, BlinkMacSystemFont, "PingFang SC", "Microsoft YaHei",
            "Helvetica Neue", Helvetica, Arial, sans-serif;

  /* 基准参数（用于 >1440 大屏放大） */
  --base-w: 1440;
}

/* 全局重置 - 精简不冗余 */
*,*::before,*::after{box-sizing:border-box;}
html,body{margin:0;padding:0;}
html{scroll-behavior:smooth;-webkit-text-size-adjust:100%;}
body{
  font-family: var(--f-base);
  color: var(--c-text);
  background: var(--c-bg);
  font-size: 15px;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  overflow-x: hidden;
}
img{max-width:100%;display:block;height:auto;}
ul,ol,li{list-style:none;margin:0;padding:0;}
h1,h2,h3,h4,h5,h6{margin:0;font-weight:700;color:var(--c-text);line-height:1.3;}
p{margin:0;}
a{color:inherit;text-decoration:none;transition:color .2s,opacity .2s;}
button{border:0;background:none;cursor:pointer;font-family:inherit;}
input,textarea{font-family:inherit;}
details summary{list-style:none;}
details summary::-webkit-details-marker{display:none;}

/* ---------- 二、基础通用：容器 / 按钮 / 区块标题 ---------- */

/* 主容器：<=1440 固定 1200px，>1440 随屏等比放大 */
.container{
  width: 1200px;
  max-width: calc(100% - 40px);
  margin: 0 auto;
  position: relative;
}
@media (min-width: 1441px){
  /* 以 1440 为基准，按可视宽度线性放大容器最大宽度至 1600 */
  .container{
    width: clamp(1200px, calc(1200px + (100vw - 1440px) * 0.8), 1600px);
    max-width: 92%;
  }
  /* 同时放大字号与留白，避免大屏空洞 */
  html{
    font-size: clamp(16px, calc(16px + (100vw - 1440px) * 0.008), 20px);
  }
  body{font-size: 1em;}
}

/* 通用按钮 */
.btn-primary, .btn-ghost, .btn-download-top, .btn-android, .btn-ios{
  display:inline-flex;align-items:center;justify-content:center;
  padding: 10px 24px;border-radius: 999px;
  font-weight:600;cursor:pointer;white-space:nowrap;
  transition:transform .2s ease, box-shadow .2s ease, background .2s ease, color .2s ease, border-color .2s ease;
  user-select:none;
}
.btn-large{padding:14px 34px;font-size:16px;}
.btn-xlarge{padding:16px 38px;font-size:17px;border-radius: var(--r-lg);}

/* 橙色实心按钮 */
.btn-primary{
  background: var(--c-primary);color:#fff;box-shadow: 0 6px 16px rgba(255,152,0,0.35);
}
.btn-primary:hover{
  background: var(--c-primary-deep);transform: translateY(-2px);box-shadow: var(--sh-hover);
}
.btn-primary:active{transform: translateY(0);}

/* 透明描边按钮 */
.btn-ghost{
  background:#fff;color: var(--c-primary-deep);
  border:2px solid var(--c-primary);
}
.btn-ghost:hover{
  background: var(--c-primary);color:#fff;transform: translateY(-2px);
  box-shadow: 0 6px 16px rgba(255,152,0,0.3);
}

/* 顶部下载按钮 */
.btn-download-top{
  background: linear-gradient(135deg, var(--c-primary), var(--c-primary-deep));
  color:#fff;padding: 9px 22px;font-size:14px;
  box-shadow: 0 4px 12px rgba(255,152,0,0.35);
}
.btn-download-top:hover{
  transform: translateY(-1px);box-shadow: 0 8px 20px rgba(255,152,0,0.45);
}

/* 安卓下载按钮 */
.btn-android{
  background: #fff;color:#2a7b3b;border:2px solid #2a7b3b;
  gap: 12px;min-width: 220px;justify-content:flex-start;
}
.btn-android:hover{
  background:#2a7b3b;color:#fff;transform: translateY(-2px);
  box-shadow: 0 10px 24px rgba(42,123,59,0.3);
}
.btn-android strong{font-size:17px;display:block;}
.btn-android span{font-size:12px;color:#888;font-weight:400;}
.btn-android:hover span{color:#d4f2dc;}

/* iOS下载按钮 */
.btn-ios{
  background: #000;color:#fff;border:2px solid #000;
  gap: 12px;min-width: 220px;justify-content:flex-start;
}
.btn-ios:hover{
  background:#fff;color:#000;transform: translateY(-2px);
  box-shadow: 0 10px 24px rgba(0,0,0,0.25);
}
.btn-ios strong{font-size:17px;display:block;}
.btn-ios span{font-size:12px;color:#bbb;font-weight:400;}
.btn-ios:hover span{color:#666;}

/* 安卓/iOS 简化图标（内联纯CSS） */
.icon-android{
  width:32px;height:32px;flex:0 0 32px;
  background:#2a7b3b;border-radius: 8px;position:relative;
}
.btn-android:hover .icon-android{background:#fff;}
.icon-android::before, .icon-android::after{
  content:"";position:absolute;left:8px;width:4px;height:14px;background:#fff;border-radius:2px;top:9px;
}
.icon-android::after{left:20px;}
.btn-android:hover .icon-android::before,
.btn-android:hover .icon-android::after{background:#2a7b3b;}

.icon-ios{
  width:32px;height:32px;flex:0 0 32px;
  background:#fff;border-radius: 8px;position:relative;
}
.btn-ios:hover .icon-ios{background:#000;}
.icon-ios::before{
  content:"";position:absolute;left:6px;top:5px;width:20px;height:22px;
  background:#000;border-radius: 3px 3px 7px 7px / 3px 3px 5px 5px;
  clip-path: polygon(50% 0, 62% 18%, 88% 14%, 78% 34%, 95% 55%, 70% 60%, 62% 82%, 50% 70%, 38% 82%, 30% 60%, 5% 55%, 22% 34%, 12% 14%, 38% 18%);
}
.btn-ios:hover .icon-ios::before{background:#fff;}

/* 区块标题 */
.section-head{margin-bottom: 52px;}
.section-head.center{text-align:center;}
.section-head.left{text-align:left;}
.section-title{
  font-size: 34px;letter-spacing: .5px;
  position:relative;display:inline-block;
}
.section-head.center .section-title::after{
  content:"";display:block;margin:16px auto 0;
  width:56px;height:4px;border-radius: 4px;
  background: linear-gradient(90deg, var(--c-primary), var(--c-accent));
}
.section-head.left .section-title{font-size:34px;}
.section-sub{
  margin-top: 14px;color:var(--c-text-2);font-size: 15px;letter-spacing: .3px;
}

/* ---------- 三、顶部导航 ---------- */
.site-header{
  position: sticky;top:0;z-index:100;
  background: rgba(255,253,248,0.92);
  backdrop-filter: saturate(180%) blur(10px);
  -webkit-backdrop-filter: saturate(180%) blur(10px);
  border-bottom:1px solid transparent;
  transition: border-color .25s, box-shadow .25s, background .25s;
}
.site-header.scrolled{
  border-bottom-color: var(--c-border);
  box-shadow: 0 2px 12px rgba(0,0,0,0.05);
  background: rgba(255,255,255,0.96);
}
.header-inner{
  display:flex;align-items:center;justify-content:space-between;
  height: 76px;
}
.logo{display:flex;align-items:center;gap:10px;font-weight:700;}
.logo img{height: 50px;width:auto;}
.logo-subtext{
  font-size: 13px;color:var(--c-text-3);font-weight:400;
  padding-left:10px;border-left:1px solid var(--c-border-2);
}
.main-nav ul{display:flex;gap: 40px;}
.main-nav .nav-link{
  position:relative;font-size:15px;color:var(--c-text-2);font-weight:500;
  padding: 6px 0;
}
.main-nav .nav-link::after{
  content:"";position:absolute;left:50%;bottom:0;transform:translateX(-50%);
  width:0;height:2px;background:var(--c-primary);
  transition: width .25s ease;
}
.main-nav .nav-link:hover{color: var(--c-primary-deep);}
.main-nav .nav-link:hover::after{width: 100%;}

/* 汉堡按钮（仅小屏显示） */
.hamburger{
  display:none;width: 42px;height: 42px;
  border-radius: 10px;background: var(--c-bg-gray);
  position:relative;
}
.hamburger span{
  display:block;position:absolute;left:11px;width:20px;height:2px;background:var(--c-text);border-radius:2px;
  transition: transform .25s, opacity .2s, top .25s;
}
.hamburger span:nth-child(1){top: 14px;}
.hamburger span:nth-child(2){top: 20px;}
.hamburger span:nth-child(3){top: 26px;}
.hamburger[aria-expanded="true"] span:nth-child(1){top:20px;transform: rotate(45deg);}
.hamburger[aria-expanded="true"] span:nth-child(2){opacity:0;}
.hamburger[aria-expanded="true"] span:nth-child(3){top:20px;transform: rotate(-45deg);}

/* ---------- 四、首屏 Hero ---------- */
.hero-section{
  position:relative;overflow:hidden;
  background: var(--c-bg-hero);
  padding: 60px 0 80px;
}
.hero-section::before,
.hero-section::after{
  content:"";position:absolute;border-radius:50%;filter: blur(60px);opacity:.55;z-index:0;
}
.hero-section::before{
  width:360px;height:360px;background:#ffcf8a;
  left:-80px;top:-80px;
}
.hero-section::after{
  width:440px;height:440px;background:#ffb266;
  right:-120px;bottom:-160px;opacity:.4;
}
.hero-inner{
  display:grid;grid-template-columns: 1.05fr 1fr;gap: 56px;align-items:center;
  position:relative;z-index:1;
}
.hero-tag{
  display:inline-block;
  background: rgba(255,255,255,0.7);
  color: var(--c-primary-deep);
  padding: 6px 14px;border-radius: 999px;
  font-size: 13px;font-weight:500;
  margin-bottom: 22px;
  border:1px solid rgba(255,152,0,0.25);
}
.hero-title{
  font-size: 48px;margin-bottom: 20px;letter-spacing: 1px;
}
.title-accent{
  background: linear-gradient(90deg, var(--c-primary), var(--c-accent));
  -webkit-background-clip: text;background-clip: text;color:transparent;
}
.hero-desc{
  color: var(--c-text-2);font-size: 16px;line-height: 1.8;margin-bottom: 34px;
  max-width: 520px;
}
.hero-btns{display:flex;gap:16px;flex-wrap:wrap;margin-bottom: 28px;}

.hero-live{display:inline-flex;align-items:center;gap:10px;color:var(--c-text-2);font-size:14px;}
.live-dot{
  width: 10px;height:10px;border-radius:50%;background:#43a047;
  position:relative;flex:0 0 10px;
}
.live-dot::before{
  content:"";position:absolute;inset:-4px;border-radius:50%;
  background:#43a047;opacity:.35;animation: pulse 1.8s ease-out infinite;
}
@keyframes pulse{
  0%{transform:scale(1);opacity:.4;}
  100%{transform:scale(2.2);opacity:0;}
}
.hero-live strong{color:#e65100;font-weight:700;}

/* Hero 右侧图 */
.hero-visual{position:relative;display:flex;justify-content:center;align-items:center;}
.hero-img-wrap{
  position:relative;width:100%;max-width: 560px;aspect-ratio: 1/0.87;
}
.hero-img-wrap img{
  width:100%;height:100%;object-fit:contain;
  filter: drop-shadow(0 24px 40px rgba(255,138,0,0.3));
  animation: float 5s ease-in-out infinite;
}
@keyframes float{
  0%,100%{transform: translateY(0);}
  50%{transform: translateY(-14px);}
}
/* 悬浮头像 */
.float-avatar{
  position:absolute;width: 64px;height:64px;border-radius:50%;overflow:hidden;
  background:#fff;padding:3px;border: 3px solid #fff;
  box-shadow: 0 10px 24px rgba(0,0,0,0.15);
  animation: bounce 3s ease-in-out infinite;
}
.float-avatar img{width:100%;height:100%;object-fit:cover;border-radius:50%;}
.float-a{top: 8%;left: -4%; animation-delay: 0s;}
.float-b{bottom: 10%;right: -2%; animation-delay: 1.2s;}
@keyframes bounce{
  0%,100%{transform: translateY(0);}
  50%{transform: translateY(-8px);}
}
/* 悬浮徽章 */
.float-badge{
  position:absolute;right: 8%;top: 18%;
  background:#fff;border-radius: 16px;
  padding: 10px 16px;display:flex;align-items:center;gap:8px;
  box-shadow: var(--sh-md);
  animation: bounce 3.6s ease-in-out infinite .6s;
}
.badge-num{
  background: linear-gradient(135deg, var(--c-accent), var(--c-primary));
  color:#fff;padding: 4px 10px;border-radius: 999px;
  font-weight:800;font-size:16px;
}
.badge-label{font-weight:700;color:var(--c-text);font-size:15px;}

/* ---------- 五、平台数据 ---------- */
.stats-section{
  padding: 80px 0;
  background: var(--c-bg-gray);
  position:relative;
}
.stats-section::before{
  content:"";position:absolute;top:0;left:0;right:0;height: 40px;
  background: linear-gradient(180deg, #ffe7c2 0%, transparent 100%);
}
.stats-grid{
  display:grid;grid-template-columns: repeat(4, 1fr);gap: 24px;
}
.stat-card{
  background: #fff;border-radius: var(--r-lg);padding: 36px 20px;
  text-align:center;position:relative;overflow:hidden;
  box-shadow: var(--sh-sm);
  transition: transform .3s ease, box-shadow .3s ease;
}
.stat-card::before{
  content:"";position:absolute;top:-60px;right:-60px;width:160px;height:160px;
  background: radial-gradient(circle, var(--c-primary-light) 0%, transparent 70%);
  opacity:.5;
}
.stat-card:hover{
  transform: translateY(-6px);
  box-shadow: 0 16px 40px rgba(255,152,0,0.18);
}
.stat-num{
  font-size: 40px;font-weight:800;line-height:1;
  background: linear-gradient(135deg, var(--c-primary), var(--c-accent));
  -webkit-background-clip:text;background-clip:text;color:transparent;
  margin-bottom: 12px;
}
.stat-label{font-size: 15px;color: var(--c-text-2);font-weight:500;}

/* ---------- 六、App界面展示 ---------- */
.app-showcase-section{padding: 88px 0;}
.app-grid{
  display:grid;grid-template-columns: repeat(3, 1fr);gap: 32px;
}
.app-card{
  margin:0;background:#fff;border-radius: var(--r-lg);overflow:hidden;
  border:1px solid var(--c-border);
  box-shadow: var(--sh-sm);
  transition: transform .3s ease, box-shadow .3s ease, border-color .3s ease;
}
.app-card:hover{
  transform: translateY(-8px);
  box-shadow: var(--sh-lg);
  border-color: var(--c-primary-light);
}
.app-img{
  background: linear-gradient(135deg, #fff8ee, #ffe8cc);
  padding: 30px 10px 0;display:flex;justify-content:center;
  aspect-ratio: 4/5;
}
.app-img img{
  width: 72%;height: 100%;object-fit: contain;object-position: bottom center;
  border-radius: 24px 24px 0 0;
  box-shadow: 0 -10px 24px rgba(0,0,0,0.1);
  transition: transform .4s ease;
}
.app-card:hover .app-img img{transform: translateY(-8px) scale(1.03);}
.app-card figcaption{padding: 22px 24px 26px;}
.app-card h3{font-size: 20px;margin-bottom: 8px;color: var(--c-text);}
.app-card p{font-size: 14px;color: var(--c-text-2);line-height: 1.7;}

/* ---------- 七、扫码下载区 ---------- */
.qr-section{
  padding: 80px 0;
  background: linear-gradient(135deg, #fff6e2 0%, #ffe3bf 100%);
  position:relative;overflow:hidden;
}
.qr-section::before{
  content:"";position:absolute;width: 500px;height:500px;
  background: radial-gradient(circle, #ffb347 0%, transparent 70%);
  left:-150px;top:-200px;opacity:.35;
}
.qr-inner{
  display:grid;grid-template-columns: 1.2fr .8fr;gap: 40px;align-items:center;
  position:relative;
}
.qr-copy .section-title{line-height:1.3;margin-bottom:0;}
.qr-copy .section-sub{max-width: 520px;margin: 18px 0 26px;}
.qr-tags{display:flex;flex-wrap:wrap;gap:12px;}
.qr-tags li{
  display:inline-flex;align-items:center;gap: 8px;
  background:#fff;padding: 10px 20px;border-radius: 999px;
  color: var(--c-primary-deep);font-weight:600;font-size: 15px;
  box-shadow: var(--sh-sm);
  transition: transform .2s ease, box-shadow .2s ease;
}
.qr-tags li:hover{transform: translateY(-2px);box-shadow: var(--sh-md);}
.qr-tags li i{
  width: 8px;height:8px;border-radius:50%;background: var(--c-primary);flex:0 0 8px;
  box-shadow: 0 0 0 4px rgba(255,152,0,.2);
}
.qr-card{
  background:#fff;border-radius: var(--r-xl);padding: 30px 28px;
  text-align:center;max-width: 320px;margin-left:auto;
  box-shadow: 0 20px 48px rgba(255,152,0,0.22);
  transition: transform .3s ease;
}
.qr-card:hover{transform: translateY(-4px);}
.qr-img{
  width: 220px;height: 220px;margin: 0 auto 16px;
  padding: 10px;background:#fff;border: 1px solid var(--c-border);
  border-radius: var(--r-md);
}
.qr-img img{width:100%;height:100%;object-fit:contain;}
.qr-tip{font-size:15px;color:var(--c-text-2);font-weight:500;}

/* ---------- 八、核心优势 ---------- */
.features-section{padding: 88px 0;}
.features-grid{
  display:grid;grid-template-columns: repeat(3, 1fr);gap: 24px;
}
.feature-card{
  background:#fff;border-radius: var(--r-lg);padding: 36px 30px;
  border:1px solid var(--c-border);
  position:relative;overflow:hidden;
  transition: transform .3s ease, box-shadow .3s ease, border-color .3s ease;
}
.feature-card::after{
  content:"";position:absolute;top:0;left:-100%;width:100%;height:100%;
  background: linear-gradient(90deg, transparent, rgba(255,152,0,0.08), transparent);
  transition: left .6s ease;
}
.feature-card:hover{
  transform: translateY(-6px);
  box-shadow: var(--sh-lg);
  border-color: var(--c-primary-light);
}
.feature-card:hover::after{left: 100%;}
.feature-icon{margin-bottom: 20px;}
.feature-icon img{
  width: 64px;height:64px;
  transition: transform .4s ease;
}
.feature-card:hover .feature-icon img{transform: rotate(-8deg) scale(1.08);}
.feature-card h3{font-size: 20px;margin-bottom: 10px;}
.feature-card p{font-size: 14.5px;color: var(--c-text-2);line-height:1.75;}

/* ---------- 九、任务类型 ---------- */
.tasks-section{
  padding: 88px 0;
  background: var(--c-bg-gray);
}
.tasks-grid{
  display:grid;grid-template-columns: repeat(6, 1fr);gap: 20px;
}
.task-card{
  background:#fff;border-radius: var(--r-md);padding: 30px 18px 24px;
  text-align:center;position:relative;
  transition: transform .3s ease, box-shadow .3s ease;
  cursor:default;
}
.task-card:hover{
  transform: translateY(-6px);
  box-shadow: 0 12px 28px rgba(255,152,0,0.18);
}
.task-icon{margin-bottom: 16px;display:flex;justify-content:center;}
.task-icon img{
  width:72px;height:72px;transition: transform .4s cubic-bezier(.34,1.56,.64,1);
}
.task-card:hover .task-icon img{transform: scale(1.12) translateY(-4px);}
.task-card h4{font-size: 17px;margin-bottom: 4px;}
.task-card p{font-size: 13px;color: var(--c-text-3);}

/* ---------- 十、用户评价 ---------- */
.reviews-section{padding: 88px 0;}
.reviews-grid{
  display:grid;grid-template-columns: repeat(3, 1fr);gap: 24px;
}
.review-card{
  background:#fff;border-radius: var(--r-lg);padding: 30px;
  border:1px solid var(--c-border);position:relative;
  transition: transform .3s ease, box-shadow .3s ease, border-color .3s ease;
}
.review-card::before{
  content:"\201C";position:absolute;top: 20px;right: 30px;
  font-size: 80px;line-height:1;color: var(--c-primary-light);
  font-family: Georgia, serif;font-weight:700;
}
.review-card:hover{
  transform: translateY(-5px);
  box-shadow: var(--sh-md);
  border-color: var(--c-primary-light);
}
.review-user{display:flex;align-items:center;gap:14px;margin-bottom: 18px;}
.review-user img{
  width:58px;height:58px;border-radius:50%;object-fit:cover;
  border:2px solid var(--c-primary-light);
  background:#eee;
}
.review-user h4{font-size:16px;margin-bottom:2px;}
.review-tag{
  display:inline-block;font-size:12px;
  padding: 2px 10px;border-radius:999px;
  background: var(--c-primary-light);color: var(--c-primary-deep);
  font-weight:500;
}
.review-text{
  color: var(--c-text-2);font-size: 14.5px;line-height: 1.85;
  margin-bottom: 16px;position:relative;z-index:1;
}
.review-stars{color:#ffb300;font-size:16px;letter-spacing:2px;}

/* ---------- 十一、下载CTA ---------- */
.cta-section{
  padding: 80px 0;
  background: var(--c-bg-cta);
  color:#fff;position:relative;overflow:hidden;
}
.cta-section::before,.cta-section::after{
  content:"";position:absolute;border-radius:50%;opacity:.25;
}
.cta-section::before{
  width: 400px;height:400px;background:#fff;
  top:-200px;right:-100px;
}
.cta-section::after{
  width: 300px;height:300px;background:#fff;
  bottom:-150px;left:-80px;
}
.cta-inner{text-align:center;position:relative;z-index:1;}
.cta-title{font-size: 38px;color:#fff;margin-bottom: 10px;}
.cta-sub{font-size: 16px;color: rgba(255,255,255,.88);margin-bottom: 36px;}
.cta-btns{display:flex;gap:20px;justify-content:center;flex-wrap:wrap;margin-bottom: 28px;}
.cta-tags{
  color: rgba(255,255,255,.9);font-size: 14px;letter-spacing:.3px;
}
.cta-tags b{
  margin: 0 12px;color: rgba(255,255,255,.55);font-weight:400;
}

/* ---------- 十二、常见问题（手风琴） ---------- */
.faq-section{padding: 88px 0;}
.faq-list{max-width: 880px;margin: 0 auto;display:flex;flex-direction:column;gap: 14px;}
.faq-item{
  background:#fff;border: 1px solid var(--c-border);
  border-radius: var(--r-md);overflow:hidden;
  transition: box-shadow .25s ease, border-color .25s ease;
}
.faq-item[open]{
  border-color: var(--c-primary-light);
  box-shadow: var(--sh-sm);
}
.faq-item summary{
  display:flex;align-items:center;justify-content:space-between;gap:20px;
  padding: 20px 26px;cursor:pointer;font-weight:600;
  color: var(--c-text);font-size: 16px;
  background:#fff;transition: background .2s ease;
}
.faq-item summary:hover{background: #fffaf0;}
.faq-item[open] summary{color: var(--c-primary-deep);background:#fff6e6;}
.faq-icon{
  width: 28px;height:28px;border-radius:50%;
  display:flex;align-items:center;justify-content:center;
  background: var(--c-primary-light);color: var(--c-primary-deep);
  font-size:20px;line-height:1;flex:0 0 28px;
  transition: transform .3s ease, background .3s ease, color .3s ease;
}
.faq-item[open] .faq-icon{
  transform: rotate(45deg);
  background: var(--c-primary);color:#fff;
}
.faq-a{
  padding: 4px 26px 22px;color:var(--c-text-2);font-size:14.5px;line-height: 1.85;
}

/* ---------- 十三、页脚 ---------- */
.site-footer{
  background: #1f2328;color:#c8ccd2;padding: 60px 0 0;
}
.footer-inner{
  display:grid;grid-template-columns: 1.4fr 1fr 1fr 1fr;gap: 44px;
  padding-bottom: 40px;
}
.footer-logo{margin-bottom: 16px;}
.footer-logo img{height: 46px;width:auto;filter: brightness(2);}
.footer-desc{font-size: 14px;color:#9aa0a8;line-height:1.8;max-width: 380px;}
.footer-col h5{
  color:#fff;font-size:16px;margin-bottom: 18px;position:relative;padding-bottom:10px;
}
.footer-col h5::after{
  content:"";position:absolute;left:0;bottom:0;width: 32px;height:2px;
  background: var(--c-primary);
}
.footer-col ul li{margin-bottom: 10px;}
.footer-col a{
  font-size:14px;color:#9aa0a8;
  position:relative;transition: color .2s ease, padding .2s ease;
}
.footer-col a:hover{color: var(--c-primary);padding-left: 6px;}
.footer-col-last{display:flex;flex-direction:column;}
.footer-qr{
  width: 120px;padding: 5px;background:#fff;border-radius: 8px;
}
.footer-qr img{width:100%;height:100%;aspect-ratio:1;object-fit:contain;}

/* 页脚底部 */
.footer-bottom{
  border-top:1px solid rgba(255,255,255,.08);
  padding: 24px 0;
}
.footer-bottom-inner{
  display:flex;flex-direction:column;align-items:center;gap:6px;
  font-size: 13px;color:#8a9099;
}
.footer-bottom-inner a{color: var(--c-primary);}
.footer-bottom-inner a:hover{text-decoration:underline;}
.footer-disclaimer{font-size:12px;color:#6b7280;}
.footer-links{
  margin-top: 18px;padding-top: 18px;
  border-top:1px dashed rgba(255,255,255,.08);
  display:flex;flex-wrap:wrap;gap: 6px 18px;justify-content:center;
  font-size: 13px;
}
.footer-links a{
  color:#8a9099;transition: color .2s;
}
.footer-links a:hover{color: var(--c-primary);}

/* ---------- 十四、返回顶部 ---------- */
.back-top{
  position:fixed;right: 24px;bottom: 30px;z-index:90;
  width: 46px;height:46px;border-radius:50%;
  background: linear-gradient(135deg, var(--c-primary), var(--c-primary-deep));
  color:#fff;font-size:22px;
  display:flex;align-items:center;justify-content:center;
  box-shadow: 0 8px 20px rgba(255,152,0,0.4);
  opacity:0;pointer-events:none;transform: translateY(10px);
  transition: opacity .3s ease, transform .3s ease, box-shadow .2s ease;
}
.back-top.show{opacity:1;pointer-events:auto;transform: translateY(0);}
.back-top:hover{
  transform: translateY(-3px);
  box-shadow: 0 12px 26px rgba(255,152,0,0.55);
}

/* ============================================================
   响应式 - 平板（769 ~ 1024px）
   ============================================================ */
@media (max-width: 1024px){
  .container{width: 96%;}
  .header-inner{height: 70px;}
  .main-nav ul{gap: 24px;}
  .hero-inner{grid-template-columns: 1fr 1fr;gap:36px;}
  .hero-title{font-size: 40px;}
  .section-title{font-size: 30px;}
  .stats-grid{grid-template-columns: repeat(2, 1fr);}
  .features-grid{grid-template-columns: repeat(2, 1fr);}
  .app-grid{grid-template-columns: repeat(2, 1fr);}
  .reviews-grid{grid-template-columns: 1fr;}
  .tasks-grid{grid-template-columns: repeat(3, 1fr);}
  .qr-inner{grid-template-columns: 1fr;}
  .qr-card{margin: 20px 0 0;}
  .footer-inner{grid-template-columns: 1.2fr 1fr 1fr;}
  .footer-col-last{grid-column: 1 / -1;}
}

/* ============================================================
   响应式 - 移动端（<= 768px）
   ============================================================ */
@media (max-width: 768px){
  body{font-size: 14px;}

  /* 导航改为汉堡 */
  .header-inner{height: 64px;}
  .logo img{height: 40px;}
  .logo-subtext{display:none;}
  .main-nav{
    position: absolute;top: 64px;left:0;right:0;
    background:#fff;border-bottom:1px solid var(--c-border);
    max-height:0;overflow:hidden;transition: max-height .3s ease;
  }
  .main-nav.open{max-height: 360px;box-shadow: var(--sh-md);}
  .main-nav ul{flex-direction:column;gap:0;padding: 6px 20px 14px;}
  .main-nav li{border-bottom: 1px dashed var(--c-border);}
  .main-nav li:last-child{border-bottom:0;}
  .main-nav .nav-link{display:block;padding: 14px 0;font-size:15px;}
  .main-nav .nav-link::after{display:none;}
  .hamburger{display:block;}
  .btn-download-top{font-size:13px;padding: 8px 16px;}

  /* Hero */
  .hero-section{padding: 36px 0 52px;}
  .hero-inner{grid-template-columns: 1fr;gap: 30px;}
  .hero-title{font-size: 30px;}
  .hero-desc{font-size:14.5px;}
  .btn-large{padding:12px 26px;font-size: 15px;}
  .hero-btns{gap: 12px;}

  /* 数据区 */
  .stats-section{padding: 50px 0;}
  .stats-grid{grid-template-columns: repeat(2, 1fr);gap: 14px;}
  .stat-card{padding: 24px 10px;border-radius: var(--r-md);}
  .stat-num{font-size: 28px;}
  .stat-label{font-size: 13px;}

  /* 通用区块标题 */
  .section-head{margin-bottom: 32px;}
  .section-title{font-size: 24px;}
  .section-head.left .section-title{font-size: 24px;}
  .section-sub{font-size:14px;}
  .app-showcase-section,.features-section,.reviews-section,.faq-section,
  .tasks-section{padding: 52px 0;}
  .qr-section{padding: 50px 0;}
  .cta-section{padding: 52px 0;}

  /* App展示 */
  .app-grid{grid-template-columns: 1fr;gap:20px;}
  .app-img{aspect-ratio: 5/4;padding-top:20px;}
  .app-img img{width:60%;}

  /* 二维码区 */
  .qr-tags li{font-size:14px;padding: 8px 16px;}
  .qr-card{max-width: 280px;padding: 22px;}
  .qr-img{width: 180px;height: 180px;}

  /* 核心优势 */
  .features-grid{grid-template-columns: 1fr;gap: 16px;}
  .feature-card{padding: 26px 22px;}

  /* 任务类型 */
  .tasks-grid{grid-template-columns: repeat(3, 1fr);gap: 12px;}
  .task-card{padding: 22px 10px 18px;border-radius: 10px;}
  .task-icon img{width: 56px;height: 56px;}
  .task-card h4{font-size: 15px;}
  .task-card p{font-size:12px;}

  /* 用户评价 */
  .reviews-grid{gap: 14px;}
  .review-card{padding: 22px;}
  .review-card::before{font-size:60px;top:14px;right:20px;}

  /* 下载CTA */
  .cta-title{font-size: 26px;}
  .cta-sub{font-size: 14px;margin-bottom: 26px;}
  .cta-btns{flex-direction:column;align-items:stretch;padding: 0 10px;}
  .btn-xlarge{min-width:auto;width:100%;padding: 14px 20px;font-size: 15px;}
  .cta-tags{padding: 0 10px;font-size: 12px;line-height:1.8;}
  .cta-tags b{display:none;}
  .cta-tags span::after{content:" · ";color:rgba(255,255,255,.5);}
  .cta-tags span:last-child::after{content:"";}

  /* FAQ */
  .faq-item summary{padding: 16px 18px;font-size:15px;}
  .faq-a{padding: 2px 18px 18px;font-size:14px;}

  /* 页脚 */
  .site-footer{padding-top: 40px;}
  .footer-inner{grid-template-columns: 1fr;gap: 28px;padding-bottom: 28px;}
  .footer-logo img{height: 40px;}
  .footer-col h5{font-size:15px;margin-bottom: 14px;}
  .footer-qr{width: 100px;}
  .footer-bottom-inner{font-size: 12px;}
  .footer-links{font-size:12px;gap:4px 14px;margin-top:14px;padding-top:14px;}

  /* 返回顶部 */
  .back-top{width:42px;height:42px;right:16px;bottom:20px;}
}

/* ============================================================
   响应式 - 小屏手机（<= 480px）
   ============================================================ */
@media (max-width: 480px){
  .container{max-width: calc(100% - 24px);}
  .hero-title{font-size: 26px;}
  .hero-section{padding-top: 26px;}
  .tasks-grid{grid-template-columns: repeat(2, 1fr);}
  .stats-grid .stat-num{font-size: 24px;}
  .btn-download-top{padding: 7px 12px;font-size: 12px;}
}

/* ---------- 小屏优化：点击态去除高亮 ---------- */
*{-webkit-tap-highlight-color: transparent;}

/* ---------- 降低动效偏好 ---------- */
@media (prefers-reduced-motion: reduce){
  *{animation-duration: .01ms !important;transition-duration:.01ms !important;}
  html{scroll-behavior:auto;}
}