/* ==========================================================================
   RapidRAW 官方网站 - 全局样式表
   配色：基于单色 logo（黑 #0A0A0A + 白 #FAFAFA）+ 暖橙强调色 #FF6B1A
   风格：扁平、现代、专业
   ========================================================================== */

/* ---------- 1. 设计令牌（Design Tokens） ---------- */
:root {
    /* 主色 - 源自 logo */
    --color-ink: #0A0A0A;            /* 主文字 / 深色背景 */
    --color-ink-soft: #1A1A1A;       /* 次级深色 */
    --color-ink-muted: #525252;      /* 弱化文字 */
    --color-ink-faint: #A3A3A3;      /* 占位 / 提示 */

    /* 背景层 */
    --color-bg: #FFFFFF;             /* 主背景 */
    --color-bg-alt: #FAFAFA;         /* 次背景（来自 logo 白） */
    --color-bg-soft: #F5F5F4;        /* 卡片 / 灰底 */
    --color-bg-dark: #0A0A0A;        /* 深色区块背景 */
    --color-bg-dark-alt: #171717;    /* 深色次背景 */

    /* 边框 */
    --color-border: #E5E5E5;
    --color-border-dark: #262626;

    /* 强调色 - 暖橙（速度 + 摄影暖调） */
    --color-accent: #FF6B1A;
    --color-accent-hover: #E55A0A;
    --color-accent-soft: #FFF1E8;
    --color-accent-dark: #FF8A4C;

    /* 功能色 */
    --color-success: #16A34A;
    --color-info: #2563EB;

    /* 排版 */
    --font-sans: "Inter", "PingFang SC", "Microsoft YaHei", "Hiragino Sans GB",
                 "Noto Sans SC", -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
    --font-mono: "JetBrains Mono", "SF Mono", "Cascadia Code", Consolas, monospace;

    /* 间距系统（8px 基准） */
    --space-1: 0.25rem;
    --space-2: 0.5rem;
    --space-3: 0.75rem;
    --space-4: 1rem;
    --space-6: 1.5rem;
    --space-8: 2rem;
    --space-12: 3rem;
    --space-16: 4rem;
    --space-20: 5rem;
    --space-24: 6rem;
    --space-32: 8rem;

    /* 圆角 */
    --radius-sm: 6px;
    --radius-md: 10px;
    --radius-lg: 16px;
    --radius-xl: 24px;
    --radius-full: 9999px;

    /* 阴影 */
    --shadow-sm: 0 1px 2px rgba(10,10,10,0.04), 0 1px 3px rgba(10,10,10,0.06);
    --shadow-md: 0 4px 6px -1px rgba(10,10,10,0.08), 0 2px 4px -1px rgba(10,10,10,0.04);
    --shadow-lg: 0 10px 25px -5px rgba(10,10,10,0.10), 0 8px 10px -6px rgba(10,10,10,0.04);
    --shadow-xl: 0 20px 40px -10px rgba(10,10,10,0.15), 0 10px 20px -10px rgba(10,10,10,0.06);
    --shadow-accent: 0 8px 24px -6px rgba(255,107,26,0.35);

    /* 布局 */
    --container-max: 1200px;
    --header-h: 72px;

    /* 过渡 */
    --transition: 200ms cubic-bezier(0.4, 0, 0.2, 1);
}

/* ---------- 2. 重置（Reset） ---------- */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; -webkit-text-size-adjust: 100%; }
body {
    font-family: var(--font-sans);
    font-size: 16px;
    line-height: 1.7;
    color: var(--color-ink);
    background: var(--color-bg);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    overflow-x: hidden;
}
img, svg, video { max-width: 100%; height: auto; display: block; }
a { color: inherit; text-decoration: none; transition: color var(--transition); }
a:hover { color: var(--color-accent); }
button { font-family: inherit; cursor: pointer; border: none; background: none; }
ul, ol { list-style: none; }
input, textarea, select { font-family: inherit; font-size: inherit; }

/* ---------- 3. 排版工具 ---------- */
h1, h2, h3, h4, h5, h6 {
    font-weight: 700;
    line-height: 1.2;
    letter-spacing: -0.02em;
    color: var(--color-ink);
}
h1 { font-size: clamp(2.25rem, 5vw, 3.75rem); font-weight: 800; letter-spacing: -0.035em; }
h2 { font-size: clamp(1.875rem, 4vw, 2.75rem); letter-spacing: -0.03em; }
h3 { font-size: clamp(1.375rem, 2.5vw, 1.75rem); }
h4 { font-size: 1.25rem; }
p  { color: var(--color-ink-muted); }
.lead { font-size: 1.125rem; line-height: 1.75; color: var(--color-ink-muted); }
.text-accent { color: var(--color-accent); }
.text-white  { color: #fff; }
.text-center { text-align: center; }
.mono { font-family: var(--font-mono); }

/* ---------- 4. 布局容器 ---------- */
.container {
    width: 100%;
    max-width: var(--container-max);
    margin: 0 auto;
    padding: 0 var(--space-6);
}
.section { padding: var(--space-24) 0; }
.section-sm { padding: var(--space-16) 0; }
.section-dark { background: var(--color-bg-dark); color: #fff; }
.section-dark h1, .section-dark h2, .section-dark h3, .section-dark h4 { color: #fff; }
.section-dark p { color: #A3A3A3; }
.section-alt { background: var(--color-bg-alt); }
.grid { display: grid; gap: var(--space-6); }
.grid-2 { grid-template-columns: repeat(2, 1fr); }
.grid-3 { grid-template-columns: repeat(3, 1fr); }
.grid-4 { grid-template-columns: repeat(4, 1fr); }
@media (max-width: 900px) {
    .grid-2, .grid-3, .grid-4 { grid-template-columns: 1fr; }
    .section { padding: var(--space-16) 0; }
}
@media (max-width: 1100px) {
    .grid-4 { grid-template-columns: repeat(2, 1fr); }
    .grid-3 { grid-template-columns: repeat(2, 1fr); }
}

/* ---------- 5. 顶部导航 ---------- */
.site-header {
    position: sticky;
    top: 0;
    z-index: 100;
    height: var(--header-h);
    background: rgba(255,255,255,0.85);
    backdrop-filter: saturate(180%) blur(20px);
    -webkit-backdrop-filter: saturate(180%) blur(20px);
    border-bottom: 1px solid var(--color-border);
    transition: box-shadow var(--transition);
}
.site-header.scrolled { box-shadow: var(--shadow-sm); }
.nav {
    height: 100%;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: var(--space-6);
}
.brand {
    display: flex;
    align-items: center;
    gap: var(--space-3);
    font-weight: 800;
    font-size: 1.25rem;
    letter-spacing: -0.02em;
    color: var(--color-ink);
}
.brand img { width: 36px; height: 36px; }
.brand:hover { color: var(--color-ink); }
.nav-links {
    display: flex;
    align-items: center;
    gap: var(--space-8);
}
.nav-links a {
    font-size: 0.95rem;
    font-weight: 500;
    color: var(--color-ink-soft);
    position: relative;
    padding: var(--space-2) 0;
}
.nav-links a:hover { color: var(--color-ink); }
.nav-links a.active { color: var(--color-accent); }
.nav-links a.active::after {
    content: "";
    position: absolute;
    left: 0; right: 0; bottom: -4px;
    height: 2px;
    background: var(--color-accent);
    border-radius: 2px;
}
.nav-cta-group { display: flex; align-items: center; gap: var(--space-3); }

/* 移动端菜单 */
.nav-toggle {
    display: none;
    width: 44px; height: 44px;
    align-items: center; justify-content: center;
    border-radius: var(--radius-sm);
}
.nav-toggle span {
    width: 22px; height: 2px; background: var(--color-ink);
    position: relative;
    transition: transform var(--transition), opacity var(--transition);
}
.nav-toggle span::before, .nav-toggle span::after {
    content: ""; position: absolute; left: 0;
    width: 22px; height: 2px; background: var(--color-ink);
    transition: transform var(--transition);
}
.nav-toggle span::before { top: -7px; }
.nav-toggle span::after  { top: 7px; }
.nav-toggle.open span { background: transparent; }
.nav-toggle.open span::before { transform: rotate(45deg) translate(5px, 5px); }
.nav-toggle.open span::after  { transform: rotate(-45deg) translate(5px, -5px); }

@media (max-width: 900px) {
    .nav-toggle { display: flex; }
    .nav-links {
        position: fixed;
        top: var(--header-h); left: 0; right: 0;
        background: #fff;
        flex-direction: column;
        align-items: stretch;
        padding: var(--space-6);
        gap: var(--space-2);
        border-bottom: 1px solid var(--color-border);
        box-shadow: var(--shadow-lg);
        transform: translateY(-120%);
        opacity: 0;
        pointer-events: none;
        transition: transform var(--transition), opacity var(--transition);
    }
    .nav-links.open { transform: translateY(0); opacity: 1; pointer-events: auto; }
    .nav-links a { padding: var(--space-3); border-radius: var(--radius-sm); }
    .nav-links a:hover { background: var(--color-bg-soft); }
    .nav-cta-group .btn-outline { display: none; }
}

/* ---------- 6. 按钮 ---------- */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: var(--space-2);
    padding: 0.85rem 1.6rem;
    border-radius: var(--radius-md);
    font-weight: 600;
    font-size: 0.95rem;
    line-height: 1;
    letter-spacing: -0.01em;
    cursor: pointer;
    transition: all var(--transition);
    white-space: nowrap;
    border: 1.5px solid transparent;
}
.btn svg { width: 18px; height: 18px; }
.btn-primary {
    background: var(--color-accent);
    color: #fff;
    box-shadow: var(--shadow-accent);
}
.btn-primary:hover {
    background: var(--color-accent-hover);
    color: #fff;
    transform: translateY(-2px);
    box-shadow: 0 12px 28px -6px rgba(255,107,26,0.45);
}
.btn-dark { background: var(--color-ink); color: #fff; }
.btn-dark:hover { background: var(--color-ink-soft); color: #fff; transform: translateY(-2px); }
.btn-outline {
    background: transparent;
    color: var(--color-ink);
    border-color: var(--color-border);
}
.btn-outline:hover { border-color: var(--color-ink); color: var(--color-ink); transform: translateY(-2px); }
.btn-ghost { background: rgba(255,255,255,0.1); color: #fff; border-color: rgba(255,255,255,0.2); }
.btn-ghost:hover { background: rgba(255,255,255,0.15); color: #fff; }
.btn-lg { padding: 1.05rem 2rem; font-size: 1.05rem; }
.btn-sm { padding: 0.55rem 1rem; font-size: 0.85rem; }
.btn-block { width: 100%; }

/* ---------- 7. 卡片 ---------- */
.card {
    background: #fff;
    border: 1px solid var(--color-border);
    border-radius: var(--radius-lg);
    padding: var(--space-8);
    transition: transform var(--transition), box-shadow var(--transition), border-color var(--transition);
}
.card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-lg);
    border-color: var(--color-ink-faint);
}
.card-icon {
    width: 56px; height: 56px;
    border-radius: var(--radius-md);
    background: var(--color-accent-soft);
    color: var(--color-accent);
    display: flex; align-items: center; justify-content: center;
    margin-bottom: var(--space-4);
}
.card-icon svg { width: 28px; height: 28px; }
.card h3 { margin-bottom: var(--space-3); }
.card p { font-size: 0.95rem; }

/* ---------- 8. 区块标题 ---------- */
.section-head {
    max-width: 720px;
    margin: 0 auto var(--space-12);
    text-align: center;
}
.section-head .eyebrow {
    display: inline-flex;
    align-items: center;
    gap: var(--space-2);
    padding: 0.35rem 0.85rem;
    background: var(--color-accent-soft);
    color: var(--color-accent);
    border-radius: var(--radius-full);
    font-size: 0.8rem;
    font-weight: 600;
    letter-spacing: 0.02em;
    text-transform: uppercase;
    margin-bottom: var(--space-4);
}
.section-head h2 { margin-bottom: var(--space-4); }
.section-head p { font-size: 1.075rem; }
.section-dark .section-head .eyebrow {
    background: rgba(255,107,26,0.15);
}
.section-dark .section-head p { color: #A3A3A3; }

/* ---------- 9. Hero 区 ---------- */
.hero {
    padding: var(--space-24) 0 var(--space-20);
    background:
        radial-gradient(circle at 15% 20%, rgba(255,107,26,0.08), transparent 40%),
        radial-gradient(circle at 85% 80%, rgba(10,10,10,0.04), transparent 40%),
        var(--color-bg);
    position: relative;
    overflow: hidden;
}
.hero-grid {
    display: grid;
    grid-template-columns: 1.1fr 1fr;
    gap: var(--space-12);
    align-items: center;
}
@media (max-width: 900px) {
    .hero-grid { grid-template-columns: 1fr; gap: var(--space-12); }
    .hero { padding: var(--space-16) 0; }
}
.hero-badge {
    display: inline-flex;
    align-items: center;
    gap: var(--space-2);
    padding: 0.4rem 0.9rem;
    background: #fff;
    border: 1px solid var(--color-border);
    border-radius: var(--radius-full);
    font-size: 0.85rem;
    font-weight: 500;
    color: var(--color-ink-soft);
    margin-bottom: var(--space-6);
    box-shadow: var(--shadow-sm);
}
.hero-badge .dot { width: 8px; height: 8px; background: var(--color-success); border-radius: 50%; }
.hero h1 { margin-bottom: var(--space-6); }
.hero h1 .grad {
    background: linear-gradient(135deg, var(--color-accent) 0%, #FF9A4D 100%);
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
}
.hero .lead { margin-bottom: var(--space-8); max-width: 560px; }
.hero-cta {
    display: flex;
    flex-wrap: wrap;
    gap: var(--space-3);
    margin-bottom: var(--space-8);
}
.hero-stats {
    display: flex;
    flex-wrap: wrap;
    gap: var(--space-8);
    padding-top: var(--space-6);
    border-top: 1px solid var(--color-border);
}
.hero-stat .num {
    font-size: 1.875rem;
    font-weight: 800;
    color: var(--color-ink);
    letter-spacing: -0.03em;
    line-height: 1.1;
}
.hero-stat .num .unit { font-size: 1.1rem; color: var(--color-accent); margin-left: 2px; }
.hero-stat .label { font-size: 0.85rem; color: var(--color-ink-muted); }

.hero-visual {
    position: relative;
    border-radius: var(--radius-xl);
    overflow: hidden;
    box-shadow: var(--shadow-xl);
    background: var(--color-bg-dark);
    aspect-ratio: 4 / 3;
}
.hero-visual img { width: 100%; height: 100%; object-fit: cover; }
.hero-visual::after {
    content: "";
    position: absolute; inset: 0;
    background: linear-gradient(to bottom, transparent 60%, rgba(10,10,10,0.4));
}
.hero-visual-tag {
    position: absolute;
    left: var(--space-4); bottom: var(--space-4);
    z-index: 2;
    display: flex; align-items: center; gap: var(--space-2);
    padding: 0.5rem 0.9rem;
    background: rgba(255,255,255,0.95);
    border-radius: var(--radius-full);
    font-size: 0.8rem;
    font-weight: 600;
    backdrop-filter: blur(8px);
}
.hero-visual-tag .dot { width: 8px; height: 8px; background: var(--color-accent); border-radius: 50%; }

/* ---------- 10. Logo 墙 / 信任标识 ---------- */
.trust-bar {
    padding: var(--space-12) 0;
    border-bottom: 1px solid var(--color-border);
    background: var(--color-bg-alt);
}
.trust-bar .label {
    text-align: center;
    font-size: 0.8rem;
    text-transform: uppercase;
    letter-spacing: 0.1em;
    color: var(--color-ink-faint);
    margin-bottom: var(--space-6);
}
.trust-logos {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    align-items: center;
    gap: var(--space-12);
}
.trust-logos .item {
    font-weight: 700;
    font-size: 1.05rem;
    color: var(--color-ink-muted);
    display: flex;
    align-items: center;
    gap: var(--space-2);
    transition: color var(--transition);
}
.trust-logos .item:hover { color: var(--color-ink); }
.trust-logos .item svg { width: 22px; height: 22px; }

/* ---------- 11. 使用场景（首页） ---------- */
.usecase-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: var(--space-6);
}
@media (max-width: 760px) { .usecase-grid { grid-template-columns: 1fr; } }
.usecase {
    position: relative;
    border-radius: var(--radius-lg);
    overflow: hidden;
    background: var(--color-bg-dark);
    aspect-ratio: 16 / 11;
    border: 1px solid var(--color-border);
    transition: transform var(--transition), box-shadow var(--transition);
}
.usecase:hover { transform: translateY(-4px); box-shadow: var(--shadow-lg); }
.usecase img { width: 100%; height: 100%; object-fit: cover; opacity: 0.85; transition: opacity var(--transition), transform var(--transition); }
.usecase:hover img { opacity: 1; transform: scale(1.04); }
.usecase-body {
    position: absolute;
    inset: auto 0 0 0;
    padding: var(--space-6);
    background: linear-gradient(to top, rgba(10,10,10,0.95), transparent);
    color: #fff;
}
.usecase-body .tag {
    display: inline-block;
    padding: 0.25rem 0.7rem;
    background: var(--color-accent);
    color: #fff;
    border-radius: var(--radius-full);
    font-size: 0.7rem;
    font-weight: 700;
    letter-spacing: 0.05em;
    text-transform: uppercase;
    margin-bottom: var(--space-2);
}
.usecase-body h3 { color: #fff; font-size: 1.2rem; margin-bottom: var(--space-2); }
.usecase-body p { color: rgba(255,255,255,0.8); font-size: 0.9rem; margin: 0; }

/* ---------- 12. 用户评价 ---------- */
.testimonials-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: var(--space-6);
}
@media (max-width: 900px) { .testimonials-grid { grid-template-columns: 1fr; } }
.testimonial {
    background: #fff;
    border: 1px solid var(--color-border);
    border-radius: var(--radius-lg);
    padding: var(--space-8);
    display: flex;
    flex-direction: column;
    gap: var(--space-4);
    transition: transform var(--transition), box-shadow var(--transition);
}
.testimonial:hover { transform: translateY(-3px); box-shadow: var(--shadow-lg); }
.testimonial .stars {
    display: flex;
    gap: 2px;
    color: var(--color-accent);
}
.testimonial .stars svg { width: 18px; height: 18px; }
.testimonial blockquote {
    font-size: 1rem;
    line-height: 1.7;
    color: var(--color-ink-soft);
    font-style: normal;
    flex: 1;
}
.testimonial-author {
    display: flex;
    align-items: center;
    gap: var(--space-3);
    padding-top: var(--space-4);
    border-top: 1px solid var(--color-border);
}
.testimonial-author .avatar {
    width: 44px; height: 44px;
    border-radius: 50%;
    background: linear-gradient(135deg, var(--color-accent), #FFB37D);
    color: #fff;
    display: flex; align-items: center; justify-content: center;
    font-weight: 700;
    font-size: 1rem;
}
.testimonial-author .name { font-weight: 700; color: var(--color-ink); font-size: 0.95rem; }
.testimonial-author .meta { font-size: 0.82rem; color: var(--color-ink-muted); }

/* ---------- 13. 功能列表（带图标） ---------- */
.feature-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: var(--space-6);
}
@media (max-width: 900px) { .feature-grid { grid-template-columns: 1fr; } }
.feature {
    padding: var(--space-8);
    background: #fff;
    border: 1px solid var(--color-border);
    border-radius: var(--radius-lg);
    transition: all var(--transition);
}
.feature:hover {
    border-color: var(--color-accent);
    box-shadow: var(--shadow-md);
    transform: translateY(-3px);
}
.feature .icon {
    width: 48px; height: 48px;
    background: var(--color-ink);
    color: #fff;
    border-radius: var(--radius-md);
    display: flex; align-items: center; justify-content: center;
    margin-bottom: var(--space-4);
}
.feature .icon svg { width: 24px; height: 24px; }
.feature h3 { font-size: 1.15rem; margin-bottom: var(--space-2); }
.feature p { font-size: 0.95rem; margin: 0; }

/* ---------- 14. 比较表 ---------- */
.compare-table-wrap {
    overflow-x: auto;
    border-radius: var(--radius-lg);
    border: 1px solid var(--color-border);
    background: #fff;
}
.compare-table {
    width: 100%;
    border-collapse: collapse;
    min-width: 720px;
}
.compare-table th, .compare-table td {
    padding: var(--space-4) var(--space-6);
    text-align: left;
    border-bottom: 1px solid var(--color-border);
}
.compare-table thead th {
    background: var(--color-bg-soft);
    font-weight: 700;
    color: var(--color-ink);
    font-size: 0.95rem;
}
.compare-table tbody tr:hover { background: var(--color-bg-alt); }
.compare-table td.feature-name { font-weight: 600; color: var(--color-ink); }
.compare-table .check { color: var(--color-success); font-weight: 700; }
.compare-table .cross  { color: var(--color-ink-faint); }
.compare-table .accent-col { background: var(--color-accent-soft); }

/* ---------- 15. 下载按钮组 ---------- */
.platform-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: var(--space-4);
}
@media (max-width: 900px) { .platform-grid { grid-template-columns: repeat(2, 1fr); } }
@media (max-width: 480px) { .platform-grid { grid-template-columns: 1fr; } }
.platform-card {
    padding: var(--space-6);
    background: #fff;
    border: 1.5px solid var(--color-border);
    border-radius: var(--radius-lg);
    text-align: center;
    transition: all var(--transition);
    cursor: pointer;
}
.platform-card:hover {
    border-color: var(--color-accent);
    box-shadow: var(--shadow-md);
    transform: translateY(-3px);
}
.platform-card .icon {
    width: 56px; height: 56px;
    margin: 0 auto var(--space-4);
    color: var(--color-ink);
}
.platform-card .icon svg { width: 100%; height: 100%; }
.platform-card h4 { font-size: 1.1rem; margin-bottom: var(--space-1); }
.platform-card .ver { font-size: 0.8rem; color: var(--color-ink-muted); margin-bottom: var(--space-4); }
.platform-card .size {
    display: inline-block;
    padding: 0.25rem 0.6rem;
    background: var(--color-bg-soft);
    border-radius: var(--radius-full);
    font-size: 0.75rem;
    color: var(--color-ink-muted);
    font-weight: 600;
}

/* ---------- 16. 代码块 ---------- */
.code-block {
    background: var(--color-bg-dark);
    border-radius: var(--radius-md);
    padding: var(--space-6);
    overflow-x: auto;
    font-family: var(--font-mono);
    font-size: 0.875rem;
    line-height: 1.7;
    color: #E5E5E5;
    border: 1px solid var(--color-border-dark);
    position: relative;
}
.code-block::before {
    content: "";
    position: absolute;
    top: 14px; left: 14px;
    width: 12px; height: 12px;
    background: #FF5F56;
    border-radius: 50%;
    box-shadow: 18px 0 0 #FFBD2E, 36px 0 0 #27C93F;
}
.code-block pre { padding-top: var(--space-6); margin: 0; white-space: pre; }
.code-block .c-key { color: #FF8A4C; }
.code-block .c-str { color: #98C379; }
.code-block .c-cmt { color: #6B7280; font-style: italic; }
.code-block .c-fn  { color: #61DAFB; }

/* ---------- 17. 时间线（关于页） ---------- */
.timeline {
    position: relative;
    padding-left: var(--space-12);
}
.timeline::before {
    content: "";
    position: absolute;
    left: 8px; top: 8px; bottom: 8px;
    width: 2px;
    background: linear-gradient(to bottom, var(--color-accent), var(--color-border));
}
.timeline-item {
    position: relative;
    padding-bottom: var(--space-8);
}
.timeline-item:last-child { padding-bottom: 0; }
.timeline-item::before {
    content: "";
    position: absolute;
    left: -38px; top: 6px;
    width: 14px; height: 14px;
    background: #fff;
    border: 2px solid var(--color-accent);
    border-radius: 50%;
}
.timeline-item .date {
    font-size: 0.8rem;
    font-weight: 700;
    color: var(--color-accent);
    text-transform: uppercase;
    letter-spacing: 0.05em;
    margin-bottom: var(--space-2);
}
.timeline-item h4 { margin-bottom: var(--space-2); }
.timeline-item p { font-size: 0.95rem; margin: 0; }

/* ---------- 18. FAQ 折叠 ---------- */
.faq-item {
    border: 1px solid var(--color-border);
    border-radius: var(--radius-md);
    background: #fff;
    overflow: hidden;
    margin-bottom: var(--space-3);
}
.faq-q {
    width: 100%;
    text-align: left;
    padding: var(--space-4) var(--space-6);
    font-weight: 600;
    font-size: 1rem;
    color: var(--color-ink);
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: var(--space-4);
}
.faq-q .icon {
    width: 24px; height: 24px;
    flex-shrink: 0;
    color: var(--color-accent);
    transition: transform var(--transition);
}
.faq-item.open .faq-q .icon { transform: rotate(45deg); }
.faq-a {
    max-height: 0;
    overflow: hidden;
    transition: max-height var(--transition);
}
.faq-item.open .faq-a { max-height: 600px; }
.faq-a-inner {
    padding: 0 var(--space-6) var(--space-6);
    color: var(--color-ink-muted);
    font-size: 0.95rem;
    line-height: 1.75;
}

/* ---------- 19. CTA 区 ---------- */
.cta-band {
    background:
        radial-gradient(circle at 80% 20%, rgba(255,107,26,0.18), transparent 50%),
        var(--color-bg-dark);
    color: #fff;
    border-radius: var(--radius-xl);
    padding: var(--space-16) var(--space-12);
    text-align: center;
    overflow: hidden;
    position: relative;
}
.cta-band h2 { color: #fff; margin-bottom: var(--space-4); }
.cta-band p { color: #A3A3A3; margin-bottom: var(--space-8); max-width: 580px; margin-left: auto; margin-right: auto; }
.cta-band .hero-cta { justify-content: center; }

/* ---------- 20. 页脚 ---------- */
.site-footer {
    background: var(--color-bg-dark);
    color: #A3A3A3;
    padding: var(--space-20) 0 var(--space-8);
}
.footer-grid {
    display: grid;
    grid-template-columns: 1.5fr repeat(3, 1fr);
    gap: var(--space-8);
    margin-bottom: var(--space-12);
}
@media (max-width: 760px) { .footer-grid { grid-template-columns: 1fr 1fr; } }
@media (max-width: 480px) { .footer-grid { grid-template-columns: 1fr; } }
.footer-brand {
    display: flex; align-items: center; gap: var(--space-3);
    margin-bottom: var(--space-4);
    color: #fff;
    font-weight: 800;
    font-size: 1.1rem;
}
.footer-brand img { width: 32px; height: 32px; }
.footer-desc { font-size: 0.9rem; line-height: 1.7; color: #A3A3A3; margin-bottom: var(--space-4); max-width: 320px; }
.footer-social { display: flex; gap: var(--space-3); }
.footer-social a {
    width: 36px; height: 36px;
    background: rgba(255,255,255,0.08);
    border-radius: var(--radius-sm);
    display: flex; align-items: center; justify-content: center;
    color: #A3A3A3;
    transition: all var(--transition);
}
.footer-social a:hover { background: var(--color-accent); color: #fff; transform: translateY(-2px); }
.footer-social svg { width: 18px; height: 18px; }
.footer-col h5 {
    color: #fff;
    font-size: 0.85rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.08em;
    margin-bottom: var(--space-4);
}
.footer-col ul li { margin-bottom: var(--space-3); }
.footer-col ul li a { font-size: 0.9rem; color: #A3A3A3; }
.footer-col ul li a:hover { color: var(--color-accent); }
.footer-bottom {
    padding-top: var(--space-8);
    border-top: 1px solid var(--color-border-dark);
    display: flex;
    flex-wrap: wrap;
    justify-content: space-between;
    align-items: center;
    gap: var(--space-4);
    font-size: 0.85rem;
}
.footer-bottom a { color: #A3A3A3; }
.footer-bottom a:hover { color: #fff; }
.footer-legal { display: flex; gap: var(--space-6); flex-wrap: wrap; }

/* ---------- 21. 下载弹窗（Modal） ---------- */
.modal-overlay {
    position: fixed;
    inset: 0;
    background: rgba(10,10,10,0.7);
    backdrop-filter: blur(8px);
    -webkit-backdrop-filter: blur(8px);
    z-index: 200;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: var(--space-6);
    opacity: 0;
    pointer-events: none;
    transition: opacity var(--transition);
}
.modal-overlay.open { opacity: 1; pointer-events: auto;  left: 0;
  right: 0;
  top: 0;
  bottom: 0;}
button { outline: none } 
.modal {
    background: #fff;
    border-radius: var(--radius-xl);
    max-width: 720px;
    width: 100%;
    max-height: 90vh;
    overflow-y: auto;
    transform: scale(0.95) translateY(20px);
    transition: transform var(--transition);
    box-shadow: var(--shadow-xl);
}
.modal-overlay.open .modal { transform: scale(1) translateY(0); }
.modal-header {
    padding: var(--space-8) var(--space-8) var(--space-4);
    text-align: center;
    border-bottom: 1px solid var(--color-border);
    position: relative;
}
.modal-close {
    position: absolute;
    top: var(--space-4); right: var(--space-4);
    width: 36px; height: 36px;
    border-radius: var(--radius-sm);
    display: flex; align-items: center; justify-content: center;
    color: var(--color-ink-muted);
    transition: all var(--transition);
}
.modal-close:hover { background: var(--color-bg-soft); color: var(--color-ink); }
.modal-header .badge {
    display: inline-flex;
    align-items: center;
    gap: var(--space-2);
    padding: 0.35rem 0.85rem;
    background: var(--color-accent-soft);
    color: var(--color-accent);
    border-radius: var(--radius-full);
    font-size: 0.78rem;
    font-weight: 700;
    margin-bottom: var(--space-3);
}
.modal-header h3 { font-size: 1.5rem; margin-bottom: var(--space-2); }
.modal-header p { font-size: 0.95rem; margin: 0; }
.modal-body {
    padding: var(--space-8);
}
.qr-row {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--space-6);
    margin-bottom: var(--space-8);
}
@media (max-width: 520px) { .qr-row { grid-template-columns: 1fr; } }
.qr-card {
    text-align: center;
    padding: var(--space-6);
    border: 1.5px solid var(--color-border);
    border-radius: var(--radius-lg);
    transition: all var(--transition);
}
.qr-card:hover { border-color: var(--color-accent); box-shadow: var(--shadow-md); }
.qr-card .qr-img {
    width: 200px; height: 200px;
    margin: 0 auto var(--space-4);
    border-radius: var(--radius-md);
    overflow: hidden;
    background: #fff;
}
.qr-card .qr-img img { width: 100%; height: 100%; object-fit: contain; }
.qr-card h4 { font-size: 1.05rem; margin-bottom: var(--space-1); }
.qr-card p { font-size: 0.82rem; margin: 0; }
.modal-extra {
    padding: var(--space-6);
    background: var(--color-bg-soft);
    border-radius: var(--radius-md);
    text-align: center;
    font-size: 0.875rem;
    color: var(--color-ink-muted);
}
.modal-extra a { color: var(--color-accent); font-weight: 600; }

/* ---------- 22. 步骤（教程） ---------- */
.steps {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: var(--space-6);
    counter-reset: step;
}
@media (max-width: 900px) { .steps { grid-template-columns: repeat(2, 1fr); } }
@media (max-width: 520px) { .steps { grid-template-columns: 1fr; } }
.step {
    position: relative;
    padding: var(--space-8) var(--space-6);
    background: #fff;
    border: 1px solid var(--color-border);
    border-radius: var(--radius-lg);
}
.step::before {
    counter-increment: step;
    content: counter(step, decimal-leading-zero);
    display: block;
    font-size: 2rem;
    font-weight: 800;
    color: var(--color-accent);
    letter-spacing: -0.04em;
    line-height: 1;
    margin-bottom: var(--space-4);
}
.step h4 { margin-bottom: var(--space-2); }
.step p { font-size: 0.9rem; margin: 0; }

/* ---------- 23. 工具类 ---------- */
.flex { display: flex; }
.flex-center { display: flex; align-items: center; justify-content: center; }
.flex-between { display: flex; align-items: center; justify-content: space-between; }
.gap-2 { gap: var(--space-2); }
.gap-3 { gap: var(--space-3); }
.gap-4 { gap: var(--space-4); }
.gap-6 { gap: var(--space-6); }
.mt-4 { margin-top: var(--space-4); }
.mt-6 { margin-top: var(--space-6); }
.mt-8 { margin-top: var(--space-8); }
.mt-12 { margin-top: var(--space-12); }
.mb-4 { margin-bottom: var(--space-4); }
.mb-6 { margin-bottom: var(--space-6); }
.mb-8 { margin-bottom: var(--space-8); }
.mb-12 { margin-bottom: var(--space-12); }

/* 滚动进入动画 */
.reveal {
    opacity: 0;
    transform: translateY(20px);
    transition: opacity 600ms ease-out, transform 600ms ease-out;
}
.reveal.visible {
    opacity: 1;
    transform: translateY(0);
}
@media (prefers-reduced-motion: reduce) {
    .reveal { opacity: 1; transform: none; transition: none; }
    html { scroll-behavior: auto; }
}

/* 选区配色 */
::selection { background: var(--color-accent); color: #fff; }