/* =====================================================
   Rottboter 官网样式 — 深空蓝科技风（匹配白色 LOGO）
   响应式 H5，兼顾欧洲/东南亚/中东浏览习惯
   ===================================================== */
:root {
    --bg: #0a0f1e;
    --bg-alt: #0d1528;
    --panel: #111c33;
    --border: #1e2c4a;
    --text: #e8eef8;
    --text-dim: #9aa9c4;
    --accent: #2f7bff;
    --accent-2: #29d3ff;
    --accent-dark: #1a54d8;
    --radius: 10px;
    --shadow: 0 6px 24px rgba(0, 10, 40, .45);
    --glow: 0 0 22px rgba(47, 123, 255, .35);
    --container: 1200px;
}

* { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", "PingFang SC", "Microsoft YaHei", Arial, sans-serif;
    background: var(--bg);
    color: var(--text);
    line-height: 1.7;
    font-size: 16px;
}
img { max-width: 100%; display: block; }
a { color: var(--accent); text-decoration: none; transition: color .2s; }
a:hover { color: var(--accent-2); }
h1, h2, h3, h4 { line-height: 1.3; font-weight: 700; }
.container { max-width: var(--container); margin: 0 auto; padding: 0 20px; }
.container-narrow { max-width: 860px; }

/* ===== Header ===== */
.site-header {
    position: sticky; top: 0; z-index: 100;
    background: rgba(6, 10, 22, .92);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid var(--border);
}
.header-inner { display: flex; align-items: center; justify-content: space-between; height: 72px; gap: 20px; }
.logo img { height: 44px; width: auto; }
.main-nav { display: flex; align-items: center; gap: 28px; flex-wrap: wrap; }
.main-nav > a { color: var(--text-dim); font-weight: 500; font-size: 15px; padding: 6px 0; }
.main-nav > a:hover, .main-nav > a.active { color: #fff; }
.main-nav > a.active { box-shadow: inset 0 -2px 0 var(--accent); }
.nav-cta {
    background: var(--accent); color: #fff !important; padding: 8px 18px !important;
    border-radius: 6px; font-weight: 600 !important;
}
.nav-cta:hover { background: var(--accent-dark); }
.header-tools { display: flex; align-items: center; gap: 14px; }
.lang-switch {
    border: 1px solid var(--border); border-radius: 6px; padding: 5px 12px;
    color: var(--text-dim); font-size: 13px; font-weight: 600;
}
.lang-switch:hover { border-color: var(--accent); color: #fff; }
.nav-toggle { display: none; background: none; border: 0; cursor: pointer; padding: 6px; }
.nav-toggle span { display: block; width: 22px; height: 2px; background: var(--text); margin: 5px 0; border-radius: 2px; }

/* ===== Hero ===== */
.hero { position: relative; height: 560px; overflow: hidden; }
.hero-slide {
    position: absolute; inset: 0; background-size: cover; background-position: center;
    opacity: 0; transition: opacity .8s ease; display: flex; align-items: center;
}
.hero-slide.active { opacity: 1; }
.hero-overlay { position: absolute; inset: 0; background: linear-gradient(90deg, rgba(5,9,22,.9) 0%, rgba(7,14,36,.6) 55%, rgba(10,20,50,.28) 100%); }
.hero-content { position: relative; z-index: 2; max-width: 720px; }
.hero-content h1 { font-size: 44px; color: #fff; margin-bottom: 16px; text-shadow: 0 2px 12px rgba(0,0,0,.5); }
.hero-content p { font-size: 18px; color: #d5dde5; margin-bottom: 28px; }
.hero-dots { position: absolute; bottom: 24px; left: 50%; transform: translateX(-50%); display: flex; gap: 10px; z-index: 3; }
.hero-dots button { width: 10px; height: 10px; border-radius: 50%; border: 0; background: rgba(255,255,255,.4); cursor: pointer; }
.hero-dots button.active { background: var(--accent); }

/* ===== Buttons ===== */
.btn { display: inline-block; padding: 12px 28px; border-radius: 8px; font-weight: 600; font-size: 15px; border: 1px solid transparent; cursor: pointer; text-align: center; }
.btn-primary { background: var(--accent); color: #fff; }
.btn-primary:hover { background: var(--accent-dark); color: #fff; }
.btn-outline { border-color: var(--accent); color: var(--accent); background: transparent; }
.btn-outline:hover { background: rgba(47,123,255,.14); color: var(--accent-2); }
.btn-lg { padding: 14px 34px; font-size: 16px; }
.btn-block { display: block; width: 100%; margin-top: 10px; }

/* ===== Stats ===== */
.stats { border-bottom: 1px solid var(--border); background: var(--bg-alt); }
.stats-grid { display: grid; grid-template-columns: repeat(4, 1fr); padding: 34px 20px; gap: 16px; }
.stat-item { text-align: center; }
.stat-num { font-size: 34px; font-weight: 800; color: var(--accent); text-shadow: 0 0 18px rgba(47,123,255,.5); }
.stat-label { color: var(--text-dim); font-size: 14px; margin-top: 4px; }

/* ===== Sections ===== */
.section { padding: 72px 0; }
.section-alt { background: var(--bg-alt); border-top: 1px solid var(--border); border-bottom: 1px solid var(--border); }
.section-head { text-align: center; max-width: 720px; margin: 0 auto 46px; }
.section-head h2 { font-size: 32px; color: #fff; position: relative; padding-bottom: 14px; }
.section-head h2::after { content: ""; position: absolute; left: 50%; bottom: 0; transform: translateX(-50%); width: 56px; height: 3px; background: linear-gradient(90deg, var(--accent), var(--accent-2)); border-radius: 2px; box-shadow: var(--glow); }
.section-head p { color: var(--text-dim); margin-top: 12px; }
.section-sub { text-align: center; color: var(--text-dim); margin-bottom: 32px; }
.section-more { text-align: center; margin-top: 40px; }

/* ===== Cards ===== */
.card-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px; }
.card-grid.grid-3 { grid-template-columns: repeat(3, 1fr); }
.card {
    background: var(--panel); border: 1px solid var(--border); border-radius: var(--radius);
    overflow: hidden; transition: transform .25s, box-shadow .25s;
    display: flex; flex-direction: column;
}
.card:hover { transform: translateY(-4px); box-shadow: var(--shadow), var(--glow); border-color: rgba(47,123,255,.55); }
.card-img { position: relative; display: block; aspect-ratio: 4 / 3; overflow: hidden; background: #070c18; }
.card-img img { width: 100%; height: 100%; object-fit: cover; transition: transform .4s; }
.card:hover .card-img img { transform: scale(1.05); }
.card-region {
    position: absolute; top: 12px; left: 12px; background: rgba(26,84,216,.92);
    color: #fff; font-size: 12px; font-weight: 600; padding: 4px 12px; border-radius: 20px;
}
.card-body { padding: 20px; flex: 1; display: flex; flex-direction: column; gap: 8px; }
.card-tag { color: var(--accent-2); font-size: 12px; font-weight: 700; letter-spacing: .04em; text-transform: uppercase; }
.card-body h3 { font-size: 18px; }
.card-body h3 a { color: #fff; }
.card-body h3 a:hover { color: var(--accent); }
.card-body p { color: var(--text-dim); font-size: 14px; flex: 1; }
.card-body time { color: var(--text-dim); font-size: 13px; }
.card-more { font-size: 14px; font-weight: 600; margin-top: 6px; }

/* ===== Features ===== */
.feature-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 22px; }
.feature-item {
    background: var(--panel); border: 1px solid var(--border); border-radius: var(--radius);
    padding: 28px 22px; text-align: center; transition: transform .25s, border-color .25s, box-shadow .25s;
}
.feature-item:hover { transform: translateY(-4px); border-color: rgba(47,123,255,.55); box-shadow: var(--glow); }
.feature-icon { font-size: 34px; margin-bottom: 12px; }
.feature-item h3 { font-size: 17px; color: #fff; margin-bottom: 8px; }
.feature-item p { color: var(--text-dim); font-size: 14px; }

/* ===== FAQ ===== */
.faq-list { display: flex; flex-direction: column; gap: 12px; }
.faq-item {
    background: var(--panel); border: 1px solid var(--border); border-radius: var(--radius);
    overflow: hidden;
}
.faq-item summary {
    cursor: pointer; padding: 18px 22px; font-weight: 600; color: #fff;
    list-style: none; position: relative; padding-right: 44px;
}
.faq-item summary::-webkit-details-marker { display: none; }
.faq-item summary::after { content: "+"; position: absolute; right: 20px; top: 50%; transform: translateY(-50%); color: var(--accent); font-size: 22px; }
.faq-item[open] summary::after { content: "−"; }
.faq-answer { padding: 0 22px 18px; color: var(--text-dim); font-size: 15px; }

/* ===== Page hero & breadcrumb ===== */
.page-hero {
    background:
        radial-gradient(ellipse 60% 90% at 85% 10%, rgba(47,123,255,.16) 0%, transparent 60%),
        linear-gradient(120deg, #0c1631 0%, #0a0f1e 100%);
    border-bottom: 1px solid var(--border);
    padding: 52px 0 36px;
}
.page-hero h1 { font-size: 34px; color: #fff; }
.breadcrumb { margin-top: 10px; color: var(--text-dim); font-size: 14px; }
.breadcrumb a { color: var(--text-dim); }
.breadcrumb a:hover { color: var(--accent); }

/* ===== Detail pages ===== */
.detail-layout { display: grid; grid-template-columns: 1fr 320px; gap: 36px; align-items: start; }
.detail-hero { border-radius: var(--radius); overflow: hidden; border: 1px solid var(--border); margin-bottom: 24px; }
.lead { font-size: 17px; color: var(--text); background: linear-gradient(90deg, rgba(47,123,255,.1), var(--panel)); border-left: 3px solid var(--accent); padding: 16px 20px; border-radius: 0 8px 8px 0; margin-bottom: 24px; }
.detail-main h2 { font-size: 24px; color: #fff; margin: 30px 0 16px; padding-left: 12px; border-left: 4px solid var(--accent); }
.rich { color: var(--text-dim); font-size: 15px; }
.rich p, .rich ul, .rich ol { margin-bottom: 14px; }
.rich ul, .rich ol { padding-left: 24px; }
.rich img { max-width: 100%; height: auto; border-radius: 8px; margin: 14px 0; }
.rich a { text-decoration: underline; }
.rich table { width: 100%; border-collapse: collapse; margin: 16px 0; font-size: 14px; }
.rich th, .rich td { border: 1px solid var(--border); padding: 10px 14px; text-align: left; }
.rich th { background: var(--panel); color: #fff; white-space: nowrap; }
.specs { background: var(--panel); border: 1px solid var(--border); border-radius: var(--radius); padding: 6px 18px; }
.detail-side { position: sticky; top: 92px; display: flex; flex-direction: column; gap: 20px; }
.side-box { background: var(--panel); border: 1px solid var(--border); border-radius: var(--radius); padding: 22px; }
.side-box h3 { font-size: 17px; color: #fff; margin-bottom: 10px; }
.side-box p { color: var(--text-dim); font-size: 14px; }
.side-list { list-style: none; }
.side-list li { padding: 9px 0; border-bottom: 1px dashed var(--border); }
.side-list li:last-child { border-bottom: 0; }
.side-list a { color: var(--text); font-size: 14px; }

/* ===== Article ===== */
.article { background: var(--panel); border: 1px solid var(--border); border-radius: var(--radius); padding: 34px; }
.article-meta { color: var(--text-dim); font-size: 13px; margin-bottom: 18px; }
.article-cta { text-align: center; margin-top: 34px; }

/* ===== About ===== */
.about-content { font-size: 16px; color: var(--text); background: var(--panel); border: 1px solid var(--border); border-radius: var(--radius); padding: 34px; }
.about-facts { margin-top: 34px; }

/* ===== Contact ===== */
.contact-layout { display: grid; grid-template-columns: 1fr 1.2fr; gap: 40px; align-items: start; }
.contact-info h2 { font-size: 26px; color: #fff; margin-bottom: 14px; }
.contact-info p { color: var(--text-dim); margin-bottom: 20px; }
.contact-list { list-style: none; display: flex; flex-direction: column; gap: 12px; color: var(--text-dim); font-size: 15px; }
.contact-form { background: var(--panel); border: 1px solid var(--border); border-radius: var(--radius); padding: 30px; display: flex; flex-direction: column; gap: 16px; }
.contact-form label { display: flex; flex-direction: column; gap: 6px; color: var(--text-dim); font-size: 14px; font-weight: 600; }
.contact-form input, .contact-form textarea {
    background: var(--bg); border: 1px solid var(--border); border-radius: 8px;
    color: var(--text); padding: 12px 14px; font-size: 15px; font-family: inherit;
}
.contact-form input:focus, .contact-form textarea:focus { outline: none; border-color: var(--accent); }
.form-row { display: grid; grid-template-columns: 1fr 1fr; gap: 16px; }
.hp-field { position: absolute; left: -9999px; height: 0; width: 0; opacity: 0; }
.form-msg { text-align: center; font-size: 14px; min-height: 20px; }
.form-msg.ok { color: var(--accent-2); }
.form-msg.err { color: #e5534b; }

/* ===== CTA band ===== */
.cta-band { background: linear-gradient(120deg, #1a54d8 0%, #2f7bff 55%, #1e8fe0 100%); padding: 54px 0; box-shadow: inset 0 0 80px rgba(0,20,80,.35); }
.cta-inner { text-align: center; }
.cta-inner h2 { color: #fff; font-size: 26px; margin-bottom: 22px; }

/* ===== Footer ===== */
.site-footer { background: #070b16; border-top: 1px solid var(--border); padding-top: 54px; }
.footer-grid { display: grid; grid-template-columns: 1.6fr 1fr 1fr 1fr; gap: 34px; padding-bottom: 40px; }
.footer-logo { height: 36px; width: auto; margin-bottom: 14px; }
.footer-col h4 { color: #fff; font-size: 15px; margin-bottom: 14px; }
.footer-col a { display: block; color: var(--text-dim); font-size: 14px; padding: 4px 0; }
.footer-col p { color: var(--text-dim); font-size: 14px; }
.contact-line { margin-bottom: 8px; }
.footer-cta { color: var(--accent) !important; font-weight: 600; margin-top: 8px; }
.footer-bottom { border-top: 1px solid var(--border); padding: 18px 0; }
.footer-bottom .container { display: flex; justify-content: space-between; flex-wrap: wrap; gap: 8px; color: var(--text-dim); font-size: 13px; }

/* ===== WhatsApp float ===== */
.wa-float {
    position: fixed; right: 22px; bottom: 22px; z-index: 90;
    width: 54px; height: 54px; border-radius: 50%;
    background: #25d366; display: flex; align-items: center; justify-content: center;
    box-shadow: 0 4px 16px rgba(0,0,0,.4); transition: transform .2s;
}
.wa-float:hover { transform: scale(1.08); }

/* ===== Pagination ===== */
.pagination { text-align: center; margin-top: 34px; }
.pagination a, .pagination span { display: inline-block; padding: 7px 14px; margin: 0 4px; border: 1px solid var(--border); border-radius: 6px; color: var(--text-dim); font-size: 14px; }
.pagination span, .pagination .active { background: var(--accent); border-color: var(--accent); color: #fff; }

/* ===== Responsive ===== */
@media (max-width: 992px) {
    .card-grid, .card-grid.grid-3 { grid-template-columns: repeat(2, 1fr); }
    .feature-grid { grid-template-columns: repeat(2, 1fr); }
    .detail-layout { grid-template-columns: 1fr; }
    .detail-side { position: static; }
    .footer-grid { grid-template-columns: 1fr 1fr; }
    .hero { height: 460px; }
    .hero-content h1 { font-size: 34px; }
    .stats-grid { grid-template-columns: repeat(2, 1fr); }
}
@media (max-width: 640px) {
    .main-nav {
        display: none; position: absolute; top: 72px; left: 0; right: 0;
        background: #070b16; border-bottom: 1px solid var(--border);
        flex-direction: column; align-items: stretch; padding: 14px 20px; gap: 4px;
    }
    .main-nav.open { display: flex; }
    .main-nav > a { padding: 12px 0; }
    .nav-toggle { display: block; }
    .hero { height: 400px; }
    .hero-content h1 { font-size: 26px; }
    .hero-content p { font-size: 15px; }
    .card-grid, .card-grid.grid-3 { grid-template-columns: 1fr; }
    .feature-grid, .contact-layout, .form-row { grid-template-columns: 1fr; }
    .section { padding: 52px 0; }
    .section-head h2 { font-size: 25px; }
    .footer-grid { grid-template-columns: 1fr; }
    .footer-bottom .container { justify-content: center; text-align: center; }
    .stats-grid { padding: 24px 20px; }
}