/* =====================================================
   胖农教育官网样式（占位品牌，上线前可整体换肤）
   设计体系：CSS 变量驱动，主色蓝 + 橙色点缀
   ===================================================== */

:root {
    --primary: #1677e0;
    --primary-dark: #0f5cb8;
    --accent: #f08300;
    --ink: #17233d;
    --ink-soft: #4a5878;
    --muted: #8b96ad;
    --line: #e6eaf2;
    --bg: #ffffff;
    --bg-alt: #f5f7fc;
    --bg-dark: #101a30;
    --navy: #243b8f;
    --teal: #0aa574;
    --violet: #7b4de0;
    --rose: #e0447c;
    --gold: #f5b301;
    --radius: 14px;
    --radius-lg: 22px;
    --shadow: 0 10px 30px rgba(23, 35, 61, .08);
    --shadow-lg: 0 18px 50px rgba(23, 35, 61, .14);
    --font: "PingFang SC", "Microsoft YaHei", "Segoe UI", system-ui, sans-serif;
}

* { margin: 0; padding: 0; box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
    font-family: var(--font);
    color: var(--ink);
    background: var(--bg);
    line-height: 1.7;
    -webkit-font-smoothing: antialiased;
}

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

.container { width: min(1180px, 92%); margin: 0 auto; }
.container-narrow { width: min(860px, 92%); }

/* ===== 按钮 ===== */
.btn {
    display: inline-block;
    padding: 10px 22px;
    border-radius: 999px;
    font-weight: 600;
    font-size: 15px;
    border: 2px solid transparent;
    cursor: pointer;
    transition: all .25s ease;
    line-height: 1.5;
}
.btn-lg { padding: 14px 32px; font-size: 16px; }
.btn-primary { background: var(--primary); color: #fff; }
.btn-primary:hover { background: var(--primary-dark); transform: translateY(-2px); box-shadow: var(--shadow); }
.btn-outline { border-color: var(--primary); color: var(--primary); background: transparent; }
.btn-outline:hover { background: var(--primary); color: #fff; }
.btn-dark { background: var(--ink); color: #fff; }
.btn-dark:hover { background: #000; transform: translateY(-2px); }
.btn-light { background: #fff; color: var(--ink); }
.btn-light:hover { transform: translateY(-2px); box-shadow: var(--shadow); }
.section.dark .btn-outline, .cta-band .btn-outline { border-color: rgba(255,255,255,.6); color: #fff; }
.section.dark .btn-outline:hover, .cta-band .btn-outline:hover { background: rgba(255,255,255,.12); }

/* ===== 头部导航 ===== */
.header {
    position: sticky;
    top: 0;
    z-index: 100;
    background: rgba(255, 255, 255, .92);
    backdrop-filter: blur(12px);
    border-bottom: 1px solid var(--line);
}
.header-inner {
    display: flex;
    align-items: center;
    gap: 32px;
    height: 72px;
}
.logo { display: flex; align-items: center; gap: 10px; }
.logo-mark {
    width: 42px; height: 42px;
    border-radius: 12px;
    display: grid; place-items: center;
    overflow: hidden;
    flex-shrink: 0;
}
.logo-mark img { width: 100%; height: 100%; object-fit: contain; }
.logo-text { display: flex; flex-direction: column; line-height: 1.2; }
.logo-name { font-size: 18px; font-weight: 800; }
.logo-sub { font-size: 10px; color: var(--muted); letter-spacing: 1px; }
.nav-menu { display: flex; gap: 6px; margin-left: auto; }
.nav-link {
    padding: 8px 16px;
    border-radius: 999px;
    font-size: 15px;
    color: var(--ink-soft);
    transition: all .2s;
}
.nav-link:hover { color: var(--primary); background: var(--bg-alt); }
.nav-link.active { color: var(--primary); font-weight: 600; }
.header-cta { margin-left: 8px; }
.burger {
    display: none;
    flex-direction: column;
    gap: 5px;
    background: none; border: 0; cursor: pointer;
    padding: 6px;
}
.burger span { width: 22px; height: 2px; background: var(--ink); border-radius: 2px; }

/* ===== 移动端菜单 ===== */
.mobile-menu {
    position: fixed; inset: 0;
    background: #fff;
    z-index: 200;
    display: none;
    flex-direction: column;
    padding: 20px;
}
.mobile-menu.open { display: flex; }
.mobile-menu-top { display: flex; justify-content: space-between; align-items: center; }
.mobile-close {
    background: none; border: 0;
    font-size: 32px; line-height: 1;
    cursor: pointer; color: var(--ink);
}
.mobile-nav { display: flex; flex-direction: column; margin: 32px 0; gap: 4px; }
.mobile-nav a {
    padding: 14px 8px;
    font-size: 18px; font-weight: 600;
    border-bottom: 1px solid var(--line);
}
.mobile-menu .btn { text-align: center; }

/* ===== Hero ===== */
.hero {
    padding: 72px 0 64px;
    background:
        radial-gradient(800px 400px at 85% -10%, rgba(36, 92, 224, .12), transparent),
        radial-gradient(600px 300px at -10% 40%, rgba(255, 122, 26, .08), transparent);
}
.hero-grid {
    display: grid;
    grid-template-columns: 1.1fr .9fr;
    gap: 48px;
    align-items: center;
}
.hero-pill {
    display: inline-flex; align-items: center; gap: 8px;
    background: #fff;
    border: 1px solid var(--line);
    padding: 6px 14px;
    border-radius: 999px;
    font-size: 13px; color: var(--ink-soft);
    box-shadow: var(--shadow);
}
.hero-pill .dot { color: var(--accent); }
.hero h1 {
    font-size: clamp(32px, 4.6vw, 52px);
    line-height: 1.25;
    font-weight: 900;
    margin: 18px 0;
    letter-spacing: -.5px;
}
.hero .hl {
    color: var(--primary);
    background: linear-gradient(transparent 65%, rgba(36, 92, 224, .15) 65%);
}
.hero-lede { font-size: 17px; color: var(--ink-soft); max-width: 560px; }
.hero-actions { display: flex; gap: 14px; margin: 28px 0 36px; flex-wrap: wrap; }
.hero-stats { display: flex; gap: 36px; flex-wrap: wrap; }
.hero-stat .num em {
    font-style: normal;
    font-size: 30px; font-weight: 900; color: var(--ink);
}
.hero-stat .lab { font-size: 13px; color: var(--muted); }

/* Hero 视觉：浏览器模拟框 */
.hero-visual { position: relative; }
.browser {
    background: #fff;
    border: 1px solid var(--line);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-lg);
    overflow: hidden;
}
.browser-bar {
    display: flex; align-items: center; gap: 6px;
    padding: 12px 16px;
    background: var(--bg-alt);
    border-bottom: 1px solid var(--line);
}
.browser-bar i { width: 10px; height: 10px; border-radius: 50%; background: #d9dee9; }
.browser-bar i:first-child { background: #ff5f57; }
.browser-bar i:nth-child(2) { background: #febc2e; }
.browser-bar i:nth-child(3) { background: #28c840; }
.browser-url {
    margin-left: 10px;
    font-size: 12px; color: var(--muted);
    background: #fff; border: 1px solid var(--line);
    padding: 3px 12px; border-radius: 999px;
}
.browser-body { padding: 14px; }
.mock-rank-row {
    display: flex; align-items: center; gap: 12px;
    padding: 12px 10px;
    border-radius: 10px;
    font-size: 14px;
}
.mock-rank-row:hover { background: var(--bg-alt); }
.mock-rank-row .rk {
    width: 26px; height: 26px;
    border-radius: 8px;
    background: var(--bg-alt);
    display: grid; place-items: center;
    font-weight: 800; color: var(--ink-soft);
    flex-shrink: 0;
}
.mock-rank-row .rk.gold { background: #fff3d6; color: #b07b00; }
.mock-rank-row .av { font-size: 20px; }
.mock-rank-row .who { font-weight: 600; }
.mock-rank-row .sc { margin-left: auto; color: var(--primary); font-weight: 700; font-size: 13px; }

.hero-badge-float {
    position: absolute;
    display: flex; align-items: center; gap: 10px;
    background: #fff;
    border: 1px solid var(--line);
    border-radius: 14px;
    padding: 10px 16px;
    box-shadow: var(--shadow-lg);
    font-size: 13px;
    animation: float 4s ease-in-out infinite;
}
.hero-badge-float .ic { font-size: 22px; }
.hero-badge-float .t { font-weight: 700; }
.hero-badge-float .s { color: var(--muted); font-size: 12px; }
.float-1 { top: -22px; right: -14px; }
.float-2 { bottom: -22px; left: -14px; animation-delay: 2s; }
@keyframes float {
    0%, 100% { transform: translateY(0); }
    50% { transform: translateY(-8px); }
}

/* ===== 信任条 ===== */
.trust-band {
    border-top: 1px solid var(--line);
    border-bottom: 1px solid var(--line);
    background: #fff;
}
.trust-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 16px;
    padding: 22px 0;
}
.trust-item { display: flex; align-items: center; gap: 12px; }
.trust-item .ic { font-size: 24px; }
.trust-item .t { font-weight: 700; font-size: 14px; }
.trust-item .s { font-size: 12px; color: var(--muted); }

/* ===== 通用 Section ===== */
.section { padding: 84px 0; }
.section.alt { background: var(--bg-alt); }
.section.dark { background: var(--bg-dark); color: #fff; }
.section-head { max-width: 640px; }
.section-head.center { margin: 0 auto 52px; text-align: center; }
.eyebrow {
    display: inline-block;
    font-size: 12px; font-weight: 700;
    letter-spacing: 2px;
    text-transform: uppercase;
    color: var(--primary);
    margin-bottom: 10px;
}
.section-title {
    font-size: clamp(26px, 3.4vw, 38px);
    font-weight: 900;
    line-height: 1.3;
    letter-spacing: -.5px;
}
.section-desc { margin-top: 12px; color: var(--ink-soft); font-size: 16px; }
.section.dark .section-desc { color: #aab6d0; }
.section.dark .eyebrow { color: #7ea2ff; }

/* ===== 特色卡片 ===== */
.cards-4 {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 20px;
}
.feature {
    background: #fff;
    border: 1px solid var(--line);
    border-radius: var(--radius-lg);
    padding: 28px 22px;
    transition: all .25s;
}
.feature:hover { transform: translateY(-4px); box-shadow: var(--shadow-lg); }
.section.alt .feature { background: #fff; }
.feature .ic {
    width: 52px; height: 52px;
    border-radius: 14px;
    display: grid; place-items: center;
    font-size: 26px;
    margin-bottom: 16px;
}
.ic.navy { background: #e8edff; }
.ic.orange { background: #fff1e3; }
.ic.teal { background: #e2f7ef; }
.ic.violet { background: #f0e9ff; }
.feature h3 { font-size: 18px; font-weight: 800; margin-bottom: 8px; }
.feature p { font-size: 14px; color: var(--ink-soft); }

/* ===== 平台模块网格 ===== */
.module-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 18px;
}
.module {
    display: flex; align-items: flex-start; gap: 14px;
    border-radius: var(--radius-lg);
    padding: 26px 22px;
    color: #fff;
    position: relative;
    overflow: hidden;
    transition: transform .25s;
}
.module:hover { transform: translateY(-4px); }
.module .idx {
    font-size: 11px; letter-spacing: 1.5px;
    opacity: .75;
    padding-top: 4px;
    white-space: nowrap;
}
.module h3 { font-size: 18px; font-weight: 800; margin-bottom: 6px; }
.module p { font-size: 13.5px; opacity: .85; }
.module .glyph {
    position: absolute;
    right: 14px; bottom: 8px;
    font-size: 44px;
    opacity: .3;
}
.m-navy { background: linear-gradient(135deg, #2b3f9e, #1d2c6e); }
.m-orange { background: linear-gradient(135deg, #f07f2e, #d95f10); }
.m-teal { background: linear-gradient(135deg, #12b981, #0a7d59); }
.m-violet { background: linear-gradient(135deg, #8b5cf6, #5b34b8); }
.m-rose { background: linear-gradient(135deg, #ec5f95, #c22e68); }
.m-ink { background: linear-gradient(135deg, #33415c, #1c2540); }

/* ===== 学习闭环步骤 ===== */
.steps {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 18px;
}
.step-card {
    background: rgba(255, 255, 255, .06);
    border: 1px solid rgba(255, 255, 255, .12);
    border-radius: var(--radius-lg);
    padding: 28px 22px;
    transition: all .25s;
}
.step-card:hover { background: rgba(255, 255, 255, .1); transform: translateY(-4px); }
.step-card .n {
    font-size: 11px; letter-spacing: 2px;
    color: #7ea2ff; font-weight: 700;
}
.step-card h4 {
    font-size: 34px;
    margin: 8px 0 10px;
    background: linear-gradient(135deg, #fff, #9db8ff);
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
}
.step-card p { font-size: 14px; color: #aab6d0; }

/* ===== 课程卡片 ===== */
.course-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 22px;
}
.course-card {
    background: #fff;
    border: 1px solid var(--line);
    border-radius: var(--radius-lg);
    overflow: hidden;
    transition: all .25s;
}
.course-card:hover { transform: translateY(-6px); box-shadow: var(--shadow-lg); }
.course-top {
    padding: 30px 24px;
    color: #fff;
    display: flex; flex-direction: column; gap: 6px;
    position: relative;
}
.course-top .big { font-size: 40px; }
.course-top .age { font-size: 12px; letter-spacing: 1.5px; opacity: .8; }
.course-top h3 { font-size: 22px; font-weight: 800; }
.course-top .one { font-size: 14px; opacity: .9; }
.ct-scratch { background: linear-gradient(135deg, #f0a13a, #e07b1a); }
.ct-py { background: linear-gradient(135deg, #2e9e6b, #1a7d4f); }
.ct-cpp { background: linear-gradient(135deg, #4a63c8, #2b3f9e); }
.ct-math { background: linear-gradient(135deg, #8b5cf6, #5b34b8); }
.course-body { padding: 22px 24px; }
.course-tags { display: flex; gap: 8px; flex-wrap: wrap; margin-bottom: 14px; }
.chip {
    font-size: 12px;
    padding: 4px 12px;
    border-radius: 999px;
    background: var(--bg-alt);
    color: var(--ink-soft);
    border: 1px solid var(--line);
}
.course-body ul { margin-bottom: 18px; }
.course-body li {
    position: relative;
    padding-left: 22px;
    font-size: 14px;
    color: var(--ink-soft);
    margin-bottom: 8px;
}
.course-body li::before {
    content: "✓";
    position: absolute; left: 0;
    color: var(--teal); font-weight: 800;
}
.course-foot {
    display: flex; justify-content: space-between; align-items: center;
    border-top: 1px solid var(--line);
    padding-top: 14px;
}
.stages { font-size: 13px; color: var(--muted); }
.course-foot .go { color: var(--primary); font-weight: 600; font-size: 14px; }
.course-foot .go:hover { text-decoration: underline; }

/* ===== 大课程块（courses.html） ===== */
.course-big {
    display: grid;
    grid-template-columns: 320px 1fr;
    background: #fff;
    border: 1px solid var(--line);
    border-radius: var(--radius-lg);
    overflow: hidden;
    margin-bottom: 24px;
    transition: box-shadow .25s;
}
.course-big:hover { box-shadow: var(--shadow-lg); }
.cb-side {
    padding: 34px 26px;
    color: #fff;
    display: flex; flex-direction: column; gap: 8px;
}
.cb-side .big { font-size: 44px; }
.cb-side .age { font-size: 12px; letter-spacing: 1.5px; opacity: .8; }
.cb-side h3 { font-size: 24px; font-weight: 800; }
.cb-side p { font-size: 14px; opacity: .9; }
.cb-body { padding: 30px 28px; display: flex; flex-direction: column; }
.cb-body ul { margin: 4px 0 18px; flex: 1; }
.cb-body li {
    position: relative;
    padding-left: 22px;
    font-size: 14.5px;
    color: var(--ink-soft);
    margin-bottom: 8px;
}
.cb-body li::before {
    content: "✓";
    position: absolute; left: 0;
    color: var(--teal); font-weight: 800;
}
.cb-foot {
    display: flex; justify-content: space-between; align-items: center;
    border-top: 1px solid var(--line);
    padding-top: 16px;
}

/* ===== 进阶路径 ===== */
.path-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 18px;
    counter-reset: path;
}
.path-step {
    background: #fff;
    border: 1px solid var(--line);
    border-radius: var(--radius-lg);
    padding: 26px 22px;
    position: relative;
    transition: all .25s;
}
.path-step:hover { transform: translateY(-4px); box-shadow: var(--shadow-lg); }
.path-step .n {
    width: 34px; height: 34px;
    border-radius: 10px;
    background: var(--primary);
    color: #fff;
    display: grid; place-items: center;
    font-weight: 800;
    margin-bottom: 14px;
}
.path-step h4 { font-size: 17px; font-weight: 800; margin-bottom: 6px; }
.path-step p { font-size: 13.5px; color: var(--ink-soft); }

/* ===== 荣誉 ===== */
.result-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 20px;
}
.result-card {
    background: #fff;
    border: 1px solid var(--line);
    border-radius: var(--radius-lg);
    overflow: hidden;
    transition: all .25s;
}
.result-card:hover { transform: translateY(-4px); box-shadow: var(--shadow-lg); }
.result-card .img { aspect-ratio: 4 / 3; background: var(--bg-alt); }
.result-card .img img { width: 100%; height: 100%; object-fit: cover; }
.placeholder-img {
    display: grid; place-items: center;
    font-size: 56px;
}
.placeholder-img.big { font-size: 96px; border-radius: var(--radius-lg); }
.result-card .cap { padding: 14px 16px; }
.result-card .cap h4 { font-size: 15px; font-weight: 700; }
.result-card .cap p { font-size: 13px; color: var(--muted); }

/* ===== CTA 横幅 ===== */
.cta-band {
    background: linear-gradient(135deg, var(--primary), var(--primary-dark));
    border-radius: var(--radius-lg);
    padding: 56px 40px;
    text-align: center;
    color: #fff;
}
.cta-band h2 { font-size: clamp(24px, 3vw, 34px); font-weight: 900; margin-bottom: 10px; }
.cta-band p { opacity: .85; margin-bottom: 26px; }
.cta-band .btns { display: flex; gap: 14px; justify-content: center; flex-wrap: wrap; }

/* ===== 页头（内页） ===== */
.page-head {
    padding: 64px 0 48px;
    background:
        radial-gradient(700px 300px at 90% -20%, rgba(36, 92, 224, .12), transparent);
    border-bottom: 1px solid var(--line);
}
.page-head h1 {
    font-size: clamp(28px, 4vw, 44px);
    font-weight: 900;
    margin: 6px 0 14px;
    letter-spacing: -.5px;
}
.page-lede { color: var(--ink-soft); max-width: 680px; font-size: 16.5px; }

/* ===== 教学平台块 ===== */
.plat-block {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 48px;
    align-items: center;
    padding: 48px 0;
    border-bottom: 1px solid var(--line);
}
.plat-block:last-of-type { border-bottom: 0; }
.plat-text .idx {
    font-size: 12px; font-weight: 700;
    letter-spacing: 2px;
    color: var(--primary);
    text-transform: uppercase;
}
.plat-text h2 { font-size: clamp(22px, 2.8vw, 30px); font-weight: 900; margin: 10px 0 12px; }
.plat-text > p { color: var(--ink-soft); margin-bottom: 18px; }
.check-list li {
    position: relative;
    padding-left: 26px;
    margin-bottom: 10px;
    font-size: 15px;
    color: var(--ink);
}
.check-list li::before {
    content: "✓";
    position: absolute; left: 0;
    width: 18px; height: 18px;
    border-radius: 6px;
    background: #e2f7ef;
    color: var(--teal);
    font-size: 12px; font-weight: 800;
    display: grid; place-items: center;
    top: 4px;
}
.plat-visual { min-height: 260px; }

/* ===== FAQ ===== */
.faq-list { display: flex; flex-direction: column; gap: 12px; }
.faq {
    background: #fff;
    border: 1px solid var(--line);
    border-radius: var(--radius);
    padding: 4px 22px;
}
.faq summary {
    cursor: pointer;
    font-weight: 700;
    font-size: 16px;
    padding: 14px 0;
    list-style: none;
    position: relative;
    padding-right: 30px;
}
.faq summary::-webkit-details-marker { display: none; }
.faq summary::after {
    content: "+";
    position: absolute; right: 0; top: 12px;
    font-size: 22px; color: var(--primary);
    transition: transform .2s;
}
.faq[open] summary::after { transform: rotate(45deg); }
.faq p { padding: 0 0 16px; color: var(--ink-soft); font-size: 15px; }

/* ===== 时间线 ===== */
.timeline { position: relative; padding-left: 28px; }
.timeline::before {
    content: "";
    position: absolute; left: 6px; top: 8px; bottom: 8px;
    width: 2px;
    background: var(--line);
}
.tl-item {
    position: relative;
    display: flex; gap: 20px;
    padding-bottom: 28px;
}
.tl-item::before {
    content: "";
    position: absolute; left: -28px; top: 8px;
    width: 14px; height: 14px;
    border-radius: 50%;
    background: var(--primary);
    border: 3px solid #dfe7ff;
}
.tl-item .year {
    font-weight: 900; color: var(--primary);
    min-width: 64px;
    font-size: 17px;
}
.tl-item h4 { font-size: 16.5px; font-weight: 800; }
.tl-item p { font-size: 14px; color: var(--ink-soft); }

/* ===== 联系 ===== */
.contact-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 18px;
}
.contact-item {
    display: flex; gap: 14px; align-items: flex-start;
    background: #fff;
    border: 1px solid var(--line);
    border-radius: var(--radius-lg);
    padding: 22px;
    font-size: 15px;
}
.contact-item .ic { font-size: 26px; }
.contact-item .t { font-weight: 700; font-size: 15px; }
.contact-item .s { color: var(--muted); font-size: 13px; }

/* ===== 页脚 ===== */
.footer {
    background: var(--bg-dark);
    color: #c3cde2;
    padding: 56px 0 0;
}
.footer-grid {
    display: grid;
    grid-template-columns: 1.4fr 1fr 1fr 1.2fr;
    gap: 32px;
    padding-bottom: 40px;
}
.footer .logo-sub { color: #6b7899; }
.footer-about p { font-size: 14px; margin-top: 14px; opacity: .8; }
.footer h5 {
    color: #fff;
    font-size: 15px;
    margin-bottom: 14px;
}
.footer-links li { margin-bottom: 9px; }
.footer-links a { font-size: 14px; opacity: .8; transition: opacity .2s; }
.footer-links a:hover { opacity: 1; color: #fff; }
.footer-contact li {
    display: flex; gap: 8px;
    font-size: 14px; margin-bottom: 10px; opacity: .85;
}
.footer-bottom {
    border-top: 1px solid rgba(255, 255, 255, .1);
    padding: 18px 0;
    font-size: 13px;
    display: flex;
    justify-content: space-between;
    flex-wrap: wrap;
    gap: 10px;
}
.footer-bottom a { opacity: .7; }
.footer-bottom a:hover { opacity: 1; }

/* ===== 返回顶部 ===== */
.to-top {
    position: fixed;
    right: 24px; bottom: 24px;
    width: 44px; height: 44px;
    border-radius: 12px;
    border: 1px solid var(--line);
    background: #fff;
    color: var(--ink);
    font-size: 18px;
    cursor: pointer;
    box-shadow: var(--shadow);
    opacity: 0;
    pointer-events: none;
    transition: all .25s;
    z-index: 90;
}
.to-top.show { opacity: 1; pointer-events: auto; }
.to-top:hover { background: var(--primary); color: #fff; }

/* ===== 入场动画 ===== */
.js .reveal {
    opacity: 0;
    transform: translateY(24px);
    transition: opacity .6s ease, transform .6s ease;
}
.js .reveal.visible { opacity: 1; transform: none; }
.js .reveal.d1 { transition-delay: .1s; }
.js .reveal.d2 { transition-delay: .2s; }
.js .reveal.d3 { transition-delay: .3s; }

/* ===== 响应式 ===== */
@media (max-width: 980px) {
    .hero-grid { grid-template-columns: 1fr; }
    .hero-visual { max-width: 520px; }
    .cards-4, .result-grid, .steps, .path-grid { grid-template-columns: repeat(2, 1fr); }
    .module-grid, .course-grid { grid-template-columns: repeat(2, 1fr); }
    .footer-grid { grid-template-columns: repeat(2, 1fr); }
    .plat-block { grid-template-columns: 1fr; gap: 28px; }
    .course-big { grid-template-columns: 1fr; }
    .cb-side { padding: 28px 24px; }
    .trust-grid { grid-template-columns: repeat(2, 1fr); }
}

@media (max-width: 640px) {
    .nav-menu, .header-cta { display: none; }
    .burger { display: flex; margin-left: auto; }
    .hero { padding: 48px 0; }
    .hero-stats { gap: 22px; }
    .hero-badge-float { display: none; }
    .cards-4, .result-grid, .steps, .path-grid,
    .module-grid, .course-grid, .contact-grid,
    .trust-grid { grid-template-columns: 1fr; }
    .footer-grid { grid-template-columns: 1fr; }
    .section { padding: 56px 0; }
    .cta-band { padding: 40px 24px; }
}