/* ============================================================
   Ehviewer官方版 · 官网样式
   风格：浅薄荷绿 / 居中Hero + 浮动截图
   ============================================================ */

:root {
    --bg: #F0FDF9;
    --bg-card: #FFFFFF;
    --line: #CCFBF1;
    --text: #134E4A;
    --text-soft: #5A8A85;
    --text-faint: #94B8B3;
    --accent: #14B8A6;
    --accent-bright: #2DD4BF;
    --accent-deep: #0D9488;
    --gradient: linear-gradient(135deg, #0D9488 0%, #14B8A6 100%);
    --radius: 16px;
    --shadow: 0 4px 20px rgba(20,184,166,0.1);
    --shadow-lg: 0 20px 50px rgba(20,184,166,0.15);
}

* { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
    font-family: "PingFang SC", "Microsoft YaHei", sans-serif;
    background: var(--bg);
    color: var(--text);
    line-height: 1.7;
    -webkit-font-smoothing: antialiased;
    overflow-x: hidden;
    padding-bottom: 70px;
}
img { max-width: 100%; display: block; }
a { text-decoration: none; color: inherit; }

.container { max-width: 1140px; margin: 0 auto; padding: 0 24px; }

/* ============ 导航 ============ */
.navbar {
    position: sticky; top: 0; z-index: 100;
    background: rgba(255,255,255,0.92);
    backdrop-filter: blur(12px);
    border-bottom: 1px solid var(--line);
}
.nav-inner { display: flex; align-items: center; justify-content: space-between; height: 64px; }
.brand { display: flex; align-items: center; gap: 10px; }
.brand-logo { height: 38px; width: 38px; border-radius: 10px; object-fit: cover; }
.brand-name { font-size: 17px; font-weight: 700; color: var(--accent-deep); }

/* ============ 按钮 ============ */
.btn {
    display: inline-flex; align-items: center; justify-content: center; gap: 8px;
    padding: 12px 26px; border-radius: 12px;
    font-size: 14px; font-weight: 600; transition: all .25s;
}
.btn-small { padding: 8px 18px; font-size: 13px; border-radius: 10px; }
.btn-lg { padding: 16px 40px; font-size: 16px; }
.btn-primary {
    background: var(--gradient); color: #fff;
    box-shadow: 0 4px 14px rgba(20,184,166,0.3);
}
.btn-primary:hover { transform: translateY(-2px); box-shadow: 0 8px 24px rgba(20,184,166,0.4); }

/* ============ 居中 Hero ============ */
.hero {
    padding: 60px 0 40px;
    text-align: center;
}
.hero-center { max-width: 600px; margin: 0 auto; }
.hero-logo {
    width: 90px; height: 90px; border-radius: 22px; object-fit: cover;
    margin: 0 auto 24px;
    box-shadow: 0 8px 30px rgba(20,184,166,0.25);
}
.hero-center h1 {
    font-size: 42px; font-weight: 800; margin-bottom: 12px;
    color: var(--text);
}
.hero-sub { font-size: 16px; color: var(--accent-deep); margin-bottom: 20px; }
.hero-desc {
    font-size: 15px; color: var(--text-soft); line-height: 1.9;
    max-width: 460px; margin: 0 auto 36px;
}

/* 浮动截图 */
.hero-photos {
    display: flex; justify-content: center; gap: 16px;
    margin-top: 40px; flex-wrap: wrap;
}
.float-photo {
    width: 130px; border-radius: 14px;
    box-shadow: var(--shadow-lg);
    transition: transform .3s;
}
.float-photo:hover { transform: translateY(-8px); }

/* ============ Section ============ */
section { padding: 70px 0; }
.section-title { font-size: 28px; font-weight: 800; text-align: center; margin-bottom: 44px; }

/* ============ 三大功能（3列） ============ */
.features { background: #fff; }
.feature-row {
    display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px;
}
.f-item {
    padding: 36px 28px; border-radius: var(--radius);
    background: var(--bg); border: 1px solid var(--line);
    text-align: center; transition: all .3s;
}
.f-item:hover { transform: translateY(-4px); box-shadow: var(--shadow); }
.f-icon { font-size: 44px; margin-bottom: 16px; }
.f-item h3 { font-size: 19px; margin-bottom: 10px; color: var(--accent-deep); }
.f-item p { font-size: 14px; color: var(--text-soft); line-height: 1.9; }

/* ============ FAQ ============ */
.faq-list { max-width: 720px; margin: 0 auto; }
.faq-list details {
    border: 1px solid var(--line); border-radius: 12px;
    padding: 18px 24px; margin-bottom: 10px; background: #fff;
}
.faq-list details[open] { border-color: var(--accent-bright); }
.faq-list summary {
    font-size: 15px; font-weight: 600; cursor: pointer;
    list-style: none; position: relative; padding-right: 28px;
}
.faq-list summary::after {
    content: "+"; position: absolute; right: 0; top: 50%;
    transform: translateY(-50%); font-size: 20px; color: var(--accent);
}
.faq-list details[open] summary::after { content: "−"; }
.faq-list details p { font-size: 14px; color: var(--text-soft); padding-top: 10px; }

/* ============ 页脚 ============ */
.footer {
    background: #134E4A; color: rgba(255,255,255,0.5); padding: 32px 0;
}
.footer-inner { display: flex; justify-content: space-between; align-items: center; flex-wrap: wrap; gap: 12px; }
.footer-brand { display: flex; align-items: center; gap: 10px; font-size: 14px; }
.footer-logo { height: 36px; width: 36px; border-radius: 8px; object-fit: cover; }
.footer-copy { font-size: 13px; }

/* ============ 底部悬浮下载栏 ============ */
.sticky-bar {
    position: fixed; bottom: 0; left: 0; right: 0; z-index: 99;
    background: rgba(255,255,255,0.95); backdrop-filter: blur(12px);
    border-top: 1px solid var(--line); padding: 10px 0;
}
.sticky-inner { display: flex; align-items: center; gap: 12px; }
.sticky-logo { height: 36px; width: 36px; border-radius: 8px; object-fit: cover; }
.sticky-text { flex: 1; display: flex; flex-direction: column; }
.sticky-text strong { font-size: 14px; }
.sticky-text span { font-size: 12px; color: var(--text-soft); }

/* ============ 滚动渐入 ============ */
.reveal { opacity: 0; transform: translateY(24px); transition: opacity .7s, transform .7s; }
.reveal.visible { opacity: 1; transform: translateY(0); }

/* ============ 响应式 ============ */
@media (max-width: 900px) {
    .hero-center h1 { font-size: 30px; }
    .feature-row { grid-template-columns: 1fr; }
    .float-photo { width: 110px; }
    .footer-inner { flex-direction: column; text-align: center; }
}