:root {
    --canvas-bg: #f8fafc;
    --surface-bg: rgba(255, 255, 255, 0.45);
    --surface-border: rgba(255, 255, 255, 0.7);
    --stroke-color: rgba(15, 23, 42, 0.04);
    --accent-glow: linear-gradient(135deg, rgba(99, 102, 241, 0.15) 0%, rgba(168, 85, 247, 0.15) 100%);
    --text-main: #0f172a;
    --text-muted: #475569;
    --text-accent: #4f46e5;
    --brand-gradient: linear-gradient(135deg, #4f46e5 0%, #7c3aed 50%, #ed64a6 100%);
    --card-radius: 18px;
}

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

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
    background-color: var(--canvas-bg);
    color: var(--text-main);
    line-height: 1.7;
    overflow-x: hidden;
    position: relative;
}

/* 氛围光 */
body::before {
    content: "";
    position: fixed;
    top: -15%;
    left: -8%;
    width: 55vw;
    height: 55vw;
    background: radial-gradient(circle, rgba(99, 102, 241, 0.10) 0%, rgba(255, 255, 255, 0) 70%);
    z-index: -1;
    pointer-events: none;
}

/* ========== 导航栏（与首页一致） ========== */
.navbar {
    position: sticky;
    top: 0;
    z-index: 1000;
    background: rgba(248, 250, 252, 0.78);
    backdrop-filter: blur(24px);
    -webkit-backdrop-filter: blur(24px);
    border-bottom: 1px solid rgba(15, 23, 42, 0.05);
    height: 72px;
    animation: fadeIn 0.7s ease both;
}
.navbar-container {
    max-width: 1400px;
    margin: 0 auto;
    height: 100%;
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0 48px;
}
.nav-brand a {
    text-decoration: none;
    color: var(--text-main);
    font-size: 19px;
    font-weight: 800;
    display: flex;
    align-items: center;
    gap: 10px;
    letter-spacing: -0.4px;
}
.nav-brand img {
    width: 30px;
    height: 30px;
    object-fit: contain;
}
.nav-right-zone {
    display: flex;
    align-items: center;
    gap: 20px;
}
.nav-menu {
    display: flex;
    gap: 4px;
}
.nav-item {
    text-decoration: none;
    color: var(--text-muted);
    font-size: 13.5px;
    font-weight: 600;
    padding: 7px 16px;
    border-radius: 9px;
    transition: all 0.25s cubic-bezier(0.16, 1, 0.3, 1);
}
.nav-item:hover {
    color: var(--text-accent);
    background: rgba(79, 70, 229, 0.05);
}
.nav-item.active {
    color: #fff;
    background: var(--text-main);
    box-shadow: 0 3px 10px rgba(15, 23, 42, 0.14);
}
.btn-github {
    display: inline-flex;
    align-items: center;
    gap: 7px;
    padding: 7px 15px;
    border-radius: 9px;
    background: #fff;
    border: 1px solid var(--surface-border);
    color: var(--text-main);
    text-decoration: none;
    font-size: 13px;
    font-weight: 600;
    box-shadow: 0 2px 6px rgba(0, 0, 0, 0.02);
    transition: all 0.25s ease;
}
.btn-github:hover {
    background: #f1f5f9;
    border-color: rgba(15, 23, 42, 0.14);
    transform: translateY(-1px);
}
.btn-github svg {
    width: 15px;
    height: 15px;
    fill: currentColor;
}

/* ========== 页面头部 ========== */
.page-header {
    max-width: 1400px;
    margin: 64px auto 36px auto;
    padding: 0 48px;
    text-align: center;
    animation: fadeInUp 0.9s cubic-bezier(0.16, 1, 0.3, 1) both;
}
.header-badge {
    display: inline-flex;
    align-items: center;
    gap: 7px;
    padding: 5px 15px;
    background: #fff;
    border: 1px solid var(--surface-border);
    border-radius: 28px;
    font-size: 12.5px;
    font-weight: 600;
    color: var(--text-accent);
    box-shadow: 0 3px 16px rgba(0, 0, 0, 0.02);
    margin-bottom: 24px;
}
.badge-dot {
    width: 5px;
    height: 5px;
    background: var(--text-accent);
    border-radius: 50%;
    display: inline-block;
    animation: pulse-dot 2s ease-in-out infinite;
}
@keyframes pulse-dot {
    0%, 100% { opacity: 1; transform: scale(1); }
    50% { opacity: 0.45; transform: scale(1.6); }
}
.page-title {
    font-size: 48px;
    font-weight: 900;
    letter-spacing: -1.5px;
    line-height: 1.15;
    margin-bottom: 16px;
    background: linear-gradient(135deg, #0f172a 30%, #3b82f6 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}
.page-subtitle {
    font-size: 16px;
    color: var(--text-muted);
    max-width: 720px;
    margin: 0 auto;
    line-height: 1.7;
}

/* ========== 分栏下载容器 ========== */
.split-download-container {
    max-width: 1400px;
    margin: 0 auto;
    padding: 20px 48px 80px 48px;
    display: flex;
    flex-direction: column;
    gap: 56px;
}
.section-block {
    display: grid;
    grid-template-columns: 260px 1fr;
    gap: 48px;
    border-bottom: 1px solid rgba(15, 23, 42, 0.05);
    padding-bottom: 56px;
}
.section-block:last-of-type {
    border-bottom: none;
    padding-bottom: 0;
}
.section-info h2 {
    font-size: 22px;
    font-weight: 800;
    color: var(--text-main);
    margin-bottom: 10px;
    display: flex;
    align-items: center;
    gap: 10px;
    letter-spacing: -0.3px;
}
.section-info p {
    font-size: 13.5px;
    color: var(--text-muted);
    line-height: 1.6;
    margin-bottom: 14px;
}
.section-link {
    font-size: 13px;
    font-weight: 600;
    color: var(--text-accent);
    text-decoration: none;
    display: inline-flex;
    align-items: center;
    gap: 4px;
    transition: gap 0.2s ease;
}
.section-link:hover {
    gap: 8px;
}
.section-icon {
    width: 26px;
    height: 26px;
    fill: currentColor;
    color: var(--text-main);
}
.download-row-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
    gap: 20px;
}
.package-item {
    background: #fff;
    border: 1px solid var(--surface-border);
    border-radius: var(--card-radius);
    padding: 28px;
    box-shadow: 0 6px 20px rgba(15, 23, 42, 0.02);
    display: flex;
    flex-direction: column;
    justify-content: space-between;
    transition: border-color 0.25s ease, box-shadow 0.25s ease, transform 0.25s ease;
}
.package-item:hover {
    border-color: rgba(79, 70, 229, 0.25);
    box-shadow: 0 14px 34px rgba(15, 23, 42, 0.05);
    transform: translateY(-3px);
}
.package-meta h3 {
    font-size: 16px;
    font-weight: 700;
    color: var(--text-main);
    margin-bottom: 4px;
}
.package-meta p {
    font-size: 13px;
    color: var(--text-muted);
    margin-bottom: 14px;
}
.tags-group {
    display: flex;
    gap: 6px;
    flex-wrap: wrap;
    margin-bottom: 20px;
}
.tag {
    font-size: 11px;
    font-weight: 600;
    background: #f1f5f9;
    border: 1px solid rgba(15, 23, 42, 0.05);
    padding: 3px 9px;
    border-radius: 6px;
    color: var(--text-muted);
}
.tag-accent {
    color: var(--text-accent);
    background: rgba(79, 70, 229, 0.05);
    border-color: rgba(79, 70, 229, 0.12);
}
.download-actions {
    display: flex;
    gap: 10px;
    align-items: center;
    flex-wrap: wrap;
}
.btn-download-action {
    background: var(--text-main);
    color: #fff;
    text-decoration: none;
    padding: 10px 20px;
    border-radius: 10px;
    font-size: 13px;
    font-weight: 600;
    transition: background-color 0.2s ease, transform 0.2s ease;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    flex: 1;
    min-width: 120px;
}
.btn-download-action:hover {
    background: var(--text-accent);
    transform: translateY(-1px);
}
.btn-checksum {
    background: transparent;
    border: 1px solid rgba(15, 23, 42, 0.1);
    color: var(--text-muted);
    padding: 10px 16px;
    border-radius: 10px;
    font-size: 12px;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.2s ease;
    white-space: nowrap;
}
.btn-checksum:hover {
    border-color: var(--text-accent);
    color: var(--text-accent);
    background: rgba(79, 70, 229, 0.03);
}
.note-text {
    font-size: 12px;
    color: var(--text-muted);
    align-self: center;
}

/* ========== 通用区块标题 ========== */
.section-header {
    text-align: center;
    margin-bottom: 48px;
}
.section-eyebrow {
    font-size: 12px;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 1.6px;
    color: var(--text-accent);
    margin-bottom: 8px;
    display: block;
}
.section-title {
    font-size: 32px;
    font-weight: 900;
    letter-spacing: -0.8px;
    color: var(--text-main);
    margin-bottom: 12px;
}
.section-desc {
    font-size: 15px;
    color: var(--text-muted);
    max-width: 640px;
    margin: 0 auto;
    line-height: 1.7;
}

/* ========== 历史版本归档 ========== */
.version-archive {
    max-width: 1400px;
    margin: 0 auto 100px auto;
    padding: 0 48px;
}
.archive-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 20px;
}
.archive-card {
    background: #fff;
    border: 1px solid var(--surface-border);
    border-radius: var(--card-radius);
    padding: 28px;
    box-shadow: 0 4px 18px rgba(15, 23, 42, 0.02);
    display: flex;
    flex-direction: column;
    transition: box-shadow 0.3s ease, transform 0.3s ease;
}
.archive-card:hover {
    box-shadow: 0 12px 32px rgba(15, 23, 42, 0.06);
    transform: translateY(-2px);
}
.archive-version {
    display: flex;
    align-items: center;
    gap: 12px;
    margin-bottom: 16px;
    flex-wrap: wrap;
}
.version-number {
    font-size: 18px;
    font-weight: 800;
    color: var(--text-main);
    letter-spacing: -0.3px;
}
.version-date {
    font-size: 12px;
    color: var(--text-muted);
    font-weight: 500;
}
.version-badge {
    font-size: 10px;
    font-weight: 700;
    padding: 2px 8px;
    border-radius: 12px;
    background: rgba(79, 70, 229, 0.08);
    color: var(--text-accent);
}
.version-badge.latest {
    background: var(--brand-gradient);
    color: #fff;
}
.archive-changes {
    list-style: none;
    display: flex;
    flex-direction: column;
    gap: 8px;
    margin-bottom: 20px;
    flex: 1;
}
.archive-changes li {
    font-size: 12.5px;
    color: var(--text-muted);
    display: flex;
    align-items: baseline;
    gap: 6px;
}
.archive-changes li::before {
    content: "•";
    color: var(--text-accent);
    font-weight: bold;
}
.archive-downloads {
    display: flex;
    gap: 10px;
    margin-top: auto;
}
.btn-archive-dl,
.btn-archive-changelog {
    font-size: 12px;
    font-weight: 600;
    padding: 7px 16px;
    border-radius: 8px;
    text-decoration: none;
    transition: all 0.2s ease;
}
.btn-archive-dl {
    background: var(--text-main);
    color: #fff;
}
.btn-archive-dl:hover {
    background: var(--text-accent);
}
.btn-archive-changelog {
    border: 1px solid rgba(15, 23, 42, 0.1);
    color: var(--text-main);
    background: transparent;
}
.btn-archive-changelog:hover {
    border-color: var(--text-accent);
    color: var(--text-accent);
}
.archive-more {
    text-align: center;
    margin-top: 36px;
}
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    padding: 12px 26px;
    border-radius: 10px;
    font-size: 14px;
    font-weight: 600;
    text-decoration: none;
    transition: all 0.3s ease;
}
.btn-secondary {
    background: #fff;
    color: var(--text-main);
    border: 1px solid var(--surface-border);
    box-shadow: 0 3px 16px rgba(0, 0, 0, 0.02);
}
.btn-secondary:hover {
    background: #f1f5f9;
    transform: translateY(-2px);
}

/* ========== 安全校验 ========== */
.verify-section {
    max-width: 1400px;
    margin: 0 auto 100px auto;
    padding: 0 48px;
}
.verify-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
    gap: 24px;
}
.verify-card {
    background: #fff;
    border: 1px solid var(--surface-border);
    border-radius: var(--card-radius);
    padding: 32px 28px;
    box-shadow: 0 4px 18px rgba(15, 23, 42, 0.02);
    transition: transform 0.3s ease;
}
.verify-card:hover {
    transform: translateY(-4px);
}
.verify-icon {
    width: 48px;
    height: 48px;
    border-radius: 14px;
    background: rgba(79, 70, 229, 0.08);
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--text-accent);
    margin-bottom: 18px;
}
.verify-card h3 {
    font-size: 17px;
    font-weight: 800;
    color: var(--text-main);
    margin-bottom: 10px;
}
.verify-card p {
    font-size: 13px;
    color: var(--text-muted);
    line-height: 1.6;
    margin-bottom: 14px;
}
.verify-link {
    font-size: 12.5px;
    font-weight: 700;
    color: var(--text-accent);
    text-decoration: none;
}
.verify-link:hover {
    text-decoration: underline;
}

/* ========== 安装指南 ========== */
.install-guide {
    max-width: 1400px;
    margin: 0 auto 100px auto;
    padding: 0 48px;
}
.guide-steps {
    display: flex;
    gap: 28px;
    justify-content: center;
    flex-wrap: wrap;
}
.guide-step {
    flex: 1;
    min-width: 200px;
    max-width: 320px;
    background: #fff;
    border: 1px solid var(--surface-border);
    border-radius: var(--card-radius);
    padding: 32px 24px;
    text-align: center;
    box-shadow: 0 4px 18px rgba(15, 23, 42, 0.02);
    transition: transform 0.3s ease;
}
.guide-step:hover {
    transform: translateY(-4px);
}
.step-icon {
    width: 48px;
    height: 48px;
    border-radius: 50%;
    background: var(--brand-gradient);
    color: #fff;
    font-weight: 900;
    font-size: 20px;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 16px;
}
.guide-step h3 {
    font-size: 16px;
    font-weight: 800;
    color: var(--text-main);
    margin-bottom: 8px;
}
.guide-step p {
    font-size: 13px;
    color: var(--text-muted);
    line-height: 1.6;
}
.guide-extra {
    text-align: center;
    margin-top: 36px;
    font-size: 14px;
    color: var(--text-muted);
}
.guide-extra a {
    color: var(--text-accent);
    font-weight: 600;
    text-decoration: none;
}
.guide-extra a:hover {
    text-decoration: underline;
}

/* ========== 页脚（与首页一致） ========== */
.footer {
    background-color: #fff;
    color: var(--text-muted);
    padding: 64px 48px;
    border-top: 1px solid rgba(15, 23, 42, 0.05);
    position: relative;
    z-index: 2;
}
.footer-container {
    max-width: 1400px;
    margin: 0 auto;
    display: grid;
    grid-template-columns: 1.6fr 1fr 1fr;
    gap: 52px;
}
.footer-brand-side {
    display: flex;
    flex-direction: column;
    gap: 14px;
}
.footer-brand-title {
    font-size: 15px;
    font-weight: 800;
    color: var(--text-main);
}
.footer-text {
    font-size: 12.5px;
    color: var(--text-muted);
    line-height: 1.6;
}
.footer-nav-col {
    display: flex;
    flex-direction: column;
    gap: 14px;
}
.footer-col-title {
    font-size: 13px;
    font-weight: 700;
    color: var(--text-main);
    letter-spacing: 0.4px;
}
.footer-links-list {
    display: flex;
    flex-direction: column;
    gap: 10px;
    list-style: none;
}
.footer-links-list a {
    color: var(--text-muted);
    text-decoration: none;
    font-size: 12.5px;
    font-weight: 500;
    transition: color 0.2s ease;
}
.footer-links-list a:hover {
    color: var(--text-accent);
}

/* ========== 动画 ========== */
@keyframes fadeIn {
    from { opacity: 0; }
    to { opacity: 1; }
}
@keyframes fadeInUp {
    from { opacity: 0; transform: translateY(28px); }
    to { opacity: 1; transform: translateY(0); }
}

/* ========== 响应式 ========== */
@media (max-width: 1024px) {
    .section-block {
        grid-template-columns: 1fr;
        gap: 28px;
    }
    .page-title {
        font-size: 38px;
    }
    .section-title {
        font-size: 28px;
    }
}
@media (max-width: 768px) {
    .navbar-container {
        padding: 0 20px;
    }
    .nav-menu {
        display: none;
    }
    .page-header {
        padding: 0 20px;
        margin: 40px auto 24px auto;
    }
    .page-title {
        font-size: 30px;
    }
    .split-download-container {
        padding: 20px 20px 60px 20px;
        gap: 36px;
    }
    .download-row-grid {
        grid-template-columns: 1fr;
    }
    .footer-container {
        grid-template-columns: 1fr;
        gap: 28px;
    }
    .footer {
        padding: 48px 24px;
    }
    .version-archive,
    .verify-section,
    .install-guide {
        padding: 0 20px;
        margin-bottom: 60px;
    }
    .archive-grid,
    .verify-grid {
        grid-template-columns: 1fr;
    }
    .guide-steps {
        flex-direction: column;
        align-items: center;
    }
}