/* ========== 关于我们页专属样式：轻量卡片 + 清晰层级 + 响应式 ========== */
/* 与站点共享变量（site.css）保持一致，深色/浅色模式自动适配 */

/* ========== 页面容器 ========== */
.about-page {
    max-width: 1080px;
    margin: 0 auto;
    padding: 104px 24px 80px;          /* 顶部预留固定导航栏 56px + 呼吸位，与首页 .container 宽度对齐 */
}

/* ========== Hero 首屏 ========== */
.about-hero {
    text-align: center;
    margin-bottom: 48px;
}

.about-hero h1 {
    font-size: clamp(26px, 5vw, 40px);
    font-weight: 600;
    letter-spacing: 0.5px;
    line-height: 1.25;
    margin-bottom: 16px;
    color: var(--text-primary);
}

.about-hero h1 .grad {
    background: linear-gradient(135deg, var(--accent-blue), var(--accent-gold));
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
}

.about-hero__desc {
    max-width: 640px;
    margin: 0 auto;
    font-size: 14px;
    font-weight: 500;
    color: var(--text-secondary);
    line-height: 1.75;
}

/* hero 区底部醒目风险提示条：左侧色条 + 图标 + 加大加粗 + 关键句着色 */
.about-hero__risk {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    max-width: 640px;
    margin: 14px auto 0;
    padding: 10px 14px;
    background: color-mix(in srgb, var(--color-up) 8%, var(--bg-secondary));
    border: 1px solid color-mix(in srgb, var(--color-up) 28%, var(--border-color));
    border-left: 4px solid var(--color-up);
    border-radius: 8px;
}

.about-hero__risk-icon {
    flex-shrink: 0;
    width: 18px;
    height: 18px;
    color: var(--color-up);
}

.about-hero__risk-text {
    margin: 0;
    font-size: 14px;
    font-weight: 600;
    color: var(--text-primary);
    line-height: 1.5;
}

.about-hero__risk-text b {
    color: var(--color-up);
    font-weight: 600;
}

@media (max-width: 680px) {
    .about-hero__risk-text {
        font-size: 13px;
    }
}

/* ========== 内容卡片网格 ========== */
.about-sections {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 16px;
    margin-bottom: 16px;
}

.about-card {
    position: relative;
    background: var(--bg-secondary);
    border: 1px solid var(--border-color);
    border-radius: 12px;
    padding: 24px;
    transition: transform 0.2s ease, border-color 0.2s ease, box-shadow 0.2s ease;
    overflow: hidden;
}

.about-card::before {
    content: '';
    position: absolute;
    left: 0;
    top: 0;
    bottom: 0;
    width: 3px;
    background: var(--accent-blue);
    transition: width 0.25s ease;
}

.about-card:hover {
    transform: translateY(-2px);
    border-color: var(--accent-blue);
    box-shadow: 0 6px 20px color-mix(in srgb, var(--accent-blue) 12%, transparent);
}

.about-card:hover::before { width: 5px; }

.about-card__head {
    display: flex;
    align-items: center;
    gap: 12px;
    margin-bottom: 16px;
}

.about-card__icon {
    width: 42px;
    height: 42px;
    border-radius: 10px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--tint-blue);
    color: var(--accent-blue);
    flex-shrink: 0;
}

.about-card__icon svg { width: 22px; height: 22px; }

.about-card h2 {
    font-size: 16px;
    font-weight: 600;
    color: var(--text-primary);
    margin: 0;
    letter-spacing: 0.3px;
}

.about-card p,
.about-card li {
    font-size: 13px;
    font-weight: 500;
    color: var(--text-secondary);
    line-height: 1.7;
}

.about-card p { margin: 0 0 8px; }
.about-card p:last-child { margin-bottom: 0; }

.about-card ul {
    margin: 0;
    padding-left: 0;
    list-style: none;
    display: flex;
    flex-direction: column;
    gap: 8px;
}

.about-card li {
    position: relative;
    padding-left: 14px;
    margin: 0;
}

.about-card li::before {
    content: '';
    position: absolute;
    left: 0;
    top: 8px;
    width: 4px;
    height: 4px;
    border-radius: 50%;
    background: var(--accent-blue);
    opacity: 0.6;
}

.about-card li strong {
    color: var(--text-primary);
    font-weight: 600;
}

/* 列表内联 h3 小标题：保持与原 strong 标签一致的视觉效果，仅补充语义层级 */
.about-card li .about-card__sub {
    display: inline;
    margin: 0;
    font-size: inherit;
    line-height: inherit;
    color: var(--text-primary);
    font-weight: 600;
}

/* ========== 联系方式卡片（通栏） ========== */
.about-contact-card {
    position: relative;
    background: var(--bg-secondary);
    border: 1px solid var(--border-color);
    border-radius: 14px;
    padding: 32px;
    margin-bottom: 16px;
    display: grid;
    grid-template-columns: 1.4fr 1fr;
    gap: 32px;
    align-items: center;
    overflow: hidden;
}

.about-contact-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 3px;
    background: linear-gradient(90deg, var(--accent-blue), var(--accent-gold));
}

.about-contact__main { position: relative; z-index: 1; }

.about-contact__label {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    font-size: 12px;
    font-weight: 600;
    color: var(--accent-blue);
    letter-spacing: 0.5px;
    margin-bottom: 12px;
}

.about-contact__label svg { width: 14px; height: 14px; }

.about-contact__title {
    font-size: 20px;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 10px;
    letter-spacing: 0.3px;
}

.about-contact__desc {
    font-size: 13px;
    font-weight: 500;
    color: var(--text-secondary);
    line-height: 1.7;
    margin-bottom: 16px;
}

.about-email {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    font-family: var(--font-mono);
    font-size: 14px;
    font-weight: 500;
    color: var(--accent-blue);
    text-decoration: none;
    padding: 8px 14px;
    border-radius: 8px;
    background: var(--tint-blue);
    border: 1px solid var(--tint-border-blue);
    transition: background 0.15s ease, transform 0.15s ease;
}

.about-email:hover { background: var(--hover-bg); transform: translateY(-1px); }

.about-email svg { width: 16px; height: 16px; }

.about-qr {
    justify-self: center;
    text-align: center;
}

.about-qr__wrap {
    background: #ffffff;
    border-radius: 12px;
    padding: 12px;
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.08);
}

.about-qr__wrap img {
    display: block;
    width: 160px;
    height: 160px;
    object-fit: contain;
}

.about-qr__tip {
    font-size: 12px;
    font-weight: 500;
    color: var(--text-muted);
    margin-top: 10px;
}

/* ========== 免责声明：复用风险警示风格（涨红语义）========== */
.about-disclaimer {
    position: relative;
    background: color-mix(in srgb, var(--color-up) 8%, var(--bg-secondary));
    border: 1px solid color-mix(in srgb, var(--color-up) 28%, var(--border-color));
    border-left: 4px solid var(--color-up);
    border-radius: 12px;
    padding: 22px 24px;
    box-shadow: 0 2px 12px color-mix(in srgb, var(--color-up) 12%, transparent);
}

.about-disclaimer__head {
    display: flex;
    align-items: center;
    gap: 8px;
    margin-bottom: 10px;
}

.about-disclaimer__icon {
    width: 20px;
    height: 20px;
    color: var(--color-up);
    flex-shrink: 0;
}

.about-disclaimer__title {
    font-size: 15px;
    font-weight: 600;
    color: var(--color-up);
    letter-spacing: 0.5px;
}

.about-disclaimer p {
    font-size: 13px;
    font-weight: 500;
    color: var(--text-primary);
    line-height: 1.7;
    margin: 0;
}

/* 免责段落中的 <strong> 着色强调，与 hero 风险条呼应 */
.about-disclaimer p strong {
    color: var(--color-up);
    font-weight: 600;
}

/* 深色模式：免责声明背景需更深，红边更亮 */
[data-theme="dark"] .about-disclaimer {
    background: color-mix(in srgb, var(--color-up) 14%, var(--bg-secondary));
    border-color: color-mix(in srgb, var(--color-up) 38%, var(--border-color));
    box-shadow: 0 2px 12px color-mix(in srgb, var(--color-up) 20%, transparent);
}

[data-theme="dark"] .about-qr__wrap {
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.5), 0 0 0 1px var(--border-color);
}

/* ========== 赞赏区：赞助服务器与算力开支（与联系方式通栏卡 .about-contact-card 同构，金色暖调点缀） ========== */
/* 刻意对齐本页轻量卡片语言：bg-secondary + 1px 边框 + 14px 圆角 + 顶部渐变条；
   不沿用首页 .support 的氛围光 / 徽章动画 / 大阴影，保持 about 页紧凑低饱和的整体观感 */
.about-support {
    margin-bottom: 16px;
}

/* 通栏卡片：左文案 + 右赞赏码，骨架与 .about-contact-card 完全一致 */
.about-support__card {
    position: relative;
    background: var(--bg-secondary);
    border: 1px solid var(--border-color);
    border-radius: 14px;
    padding: 32px;
    display: grid;
    grid-template-columns: 1.4fr 1fr;
    gap: 32px;
    align-items: center;
    overflow: hidden;
}

/* 顶部渐变条：金→蓝，与联系方式卡（蓝→金）镜像呼应，金色为主强调赞助主题 */
.about-support__card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 3px;
    background: linear-gradient(90deg, var(--accent-gold), var(--accent-blue));
}

.about-support__left { position: relative; z-index: 1; }

/* 小标签：对齐 .about-contact__label 排版，改用金色语义区分赞助区块 */
.about-support__label {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    font-size: 12px;
    font-weight: 600;
    color: var(--accent-gold);
    letter-spacing: 0.5px;
    margin-bottom: 12px;
}

.about-support__label svg { width: 14px; height: 14px; }

.about-support__title {
    font-size: 20px;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 10px;
    letter-spacing: 0.3px;
}

.about-support__desc {
    font-size: 13px;
    color: var(--text-secondary);
    font-weight: 500;
    margin-bottom: 14px;
    line-height: 1.7;
}

/* 关键用途强调着色：金色贴合"服务器/算力"投入主题 */
.about-support__desc strong {
    color: var(--accent-gold);
    font-weight: 600;
}

/* ========== 算力消耗数据带：用累计 token 与成本佐证赞助必要性 ========== */
/* 复用 .llm-stat-num 滚动机制（千分位 + 视口触发 + reduced-motion 降级）；
   贴合本页轻量低饱和语言：金色淡底 + 微边框，避免实色块 */
.about-support__stat {
    display: flex;
    align-items: center;
    gap: 22px;
    margin: 6px 0 14px;
    padding: 13px 20px;
    border-radius: 12px;
    background: color-mix(in srgb, var(--accent-gold) 6%, transparent);
    border: 1px solid color-mix(in srgb, var(--accent-gold) 16%, transparent);
}

.about-support__stat-item {
    display: flex;
    flex-direction: column;
    gap: 4px;
    min-width: 0;
}

.about-support__stat-label {
    font-size: 11px;
    color: var(--text-muted);
    font-weight: 500;
    letter-spacing: 0.2px;
}

.about-support__stat-value {
    display: flex;
    align-items: baseline;
    gap: 4px;
    font-variant-numeric: tabular-nums;   /* 滚动时数字等宽，避免宽度跳动 */
}

/* 覆写 .llm-stat-num 视觉：纯暖金、缩号适配紧凑卡片（用 .about-support__stat 前缀提升 specificity） */
.about-support__stat .about-support__stat-num {
    color: var(--accent-gold);
    font-size: 22px;
    font-weight: 600;
    line-height: 1;
    letter-spacing: 0.3px;
}

.about-support__stat-prefix {
    font-size: 15px;
    color: var(--accent-gold);
    font-weight: 600;
}

.about-support__stat-unit {
    font-size: 12px;
    font-weight: 500;
    color: var(--text-muted);
}

/* 竖向渐变分隔线：上下淡出，呼应首页 .llm-stat-divider 风格 */
.about-support__stat-divider {
    width: 1px;
    align-self: stretch;
    background: linear-gradient(180deg, transparent, color-mix(in srgb, var(--accent-gold) 30%, transparent) 30%, color-mix(in srgb, var(--accent-gold) 30%, transparent) 70%, transparent);
}

.about-support__tip {
    font-size: 12px;
    color: var(--text-muted);
    font-weight: 500;
}

/* 赞赏码：复用 .about-qr__wrap 白底卡片语言（轻阴影），尺寸与公众号二维码统一为 160px */
.about-support__qr {
    justify-self: center;
    background: #ffffff;
    border-radius: 12px;
    padding: 12px;
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.08);
    -webkit-touch-callout: default;  /* 允许 iOS/微信长按唤起系统菜单（识别二维码） */
    -webkit-user-select: none;
    user-select: none;
}

.about-support__qr img {
    display: block;
    width: 160px;
    height: 160px;
    object-fit: contain;
    -webkit-user-drag: none;
    pointer-events: auto;
}

/* 深色模式：白底必须保留（微信可扫前提），按 .about-qr__wrap 加深阴影 + 微弱边框 */
[data-theme="dark"] .about-support__qr {
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.5), 0 0 0 1px var(--border-color);
}

/* 赞赏区专属响应式：窄屏堆叠为单列居中，与联系方式卡一致 */
@media (max-width: 680px) {
    .about-support__card {
        grid-template-columns: 1fr;
        padding: 24px 20px;
        gap: 24px;
        text-align: center;
    }
    .about-support__qr img { width: 140px; height: 140px; }
    /* 数据带在居中布局下水平居中，分隔线隐藏 */
    .about-support__stat { justify-content: center; }
    .about-support__stat-divider { display: none; }
}

/* 极窄屏：数据带紧凑收窄 */
@media (max-width: 480px) {
    .about-support__stat { gap: 14px; padding: 12px 14px; }
    .about-support__stat .about-support__stat-num { font-size: 19px; }
}

/* ========== 友情链接：推广支持的友情网站（通栏卡，骨架对齐 .about-contact-card） ========== */
/* 刻意复用联系方式通栏卡语言：bg-secondary + 1px 边框 + 14px 圆角 + 顶部色条 + 左文案右标识；
   左侧介绍 + 访问按钮，右侧品牌信息卡（淡蓝底）替代二维码位 */
.about-friends-card {
    position: relative;
    background: var(--bg-secondary);
    border: 1px solid var(--border-color);
    border-radius: 14px;
    padding: 32px;
    margin-bottom: 16px;
    display: grid;
    grid-template-columns: 1.4fr 1fr;
    gap: 32px;
    align-items: center;
    overflow: hidden;
}

/* 顶部纯蓝条：与联系方式（蓝→金）、赞赏（金→蓝）形成视觉区分 */
.about-friends-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 3px;
    background: var(--accent-blue);
}

.about-friends__main { position: relative; z-index: 1; }

/* 小标签：对齐 .about-contact__label 排版，蓝色语义 */
.about-friends__label {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    font-size: 12px;
    font-weight: 600;
    color: var(--accent-blue);
    letter-spacing: 0.5px;
    margin-bottom: 12px;
}

.about-friends__label svg { width: 14px; height: 14px; }

.about-friends__title {
    font-size: 20px;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 10px;
    letter-spacing: 0.3px;
}

.about-friends__desc {
    font-size: 13px;
    font-weight: 500;
    color: var(--text-secondary);
    line-height: 1.7;
    margin-bottom: 16px;
}

/* 描述中服务关键词着色强调，与联系方式 desc 风格呼应 */
.about-friends__desc strong {
    color: var(--accent-blue);
    font-weight: 600;
}

/* 访问链接：复用 .about-email 蓝色按钮语言 */
.about-friends__link {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    font-family: var(--font-mono);
    font-size: 14px;
    font-weight: 500;
    color: var(--accent-blue);
    text-decoration: none;
    padding: 8px 14px;
    border-radius: 8px;
    background: var(--tint-blue);
    border: 1px solid var(--tint-border-blue);
    transition: background 0.15s ease, transform 0.15s ease;
}

.about-friends__link:hover { background: var(--hover-bg); transform: translateY(-1px); }
.about-friends__link svg { width: 16px; height: 16px; }

/* 右侧品牌信息卡：淡蓝底居中展示网站标识与服务关键词，替代二维码位 */
.about-friends__brand {
    justify-self: center;
    text-align: center;
    width: 100%;
    max-width: 240px;
    padding: 22px 20px;
    background: var(--tint-blue);
    border: 1px solid var(--tint-border-blue);
    border-radius: 12px;
}

.about-friends__brand-name {
    font-size: 16px;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 4px;
    letter-spacing: 0.3px;
}

.about-friends__brand-en {
    font-size: 12px;
    font-family: var(--font-mono);
    color: var(--text-muted);
    margin-bottom: 14px;
}

.about-friends__brand-tags {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 6px;
}

/* 服务关键词标签：极淡底色 + 彩色文字的轻量标签语言，不用实色胶囊 */
.about-friends__brand-tags span {
    font-size: 11px;
    font-weight: 500;
    color: var(--accent-blue);
    padding: 3px 9px;
    border-radius: 20px;
    background: var(--bg-secondary);
    border: 1px solid var(--tint-border-blue);
}

/* 深色模式：关键词标签底色换为蓝色淡底，保持可读 */
[data-theme="dark"] .about-friends__brand-tags span {
    background: color-mix(in srgb, var(--accent-blue) 12%, transparent);
}

/* ========== 响应式 ========== */
@media (max-width: 680px) {
    .about-page { padding: 88px 18px 60px; }
    .about-hero { margin-bottom: 36px; }
    .about-sections { grid-template-columns: 1fr; }
    .about-card { padding: 20px; }
    .about-contact-card {
        grid-template-columns: 1fr;
        padding: 24px 20px;
        gap: 24px;
        text-align: center;
    }
    .about-email { margin: 0 auto; }
    .about-friends-card {
        grid-template-columns: 1fr;
        padding: 24px 20px;
        gap: 24px;
        text-align: center;
    }
    .about-friends__link { margin: 0 auto; }
    .about-qr__wrap img { width: 140px; height: 140px; }
    .about-disclaimer { padding: 18px 20px; }
}

/* ========== 无障碍：尊重 reduced-motion ========== */
@media (prefers-reduced-motion: reduce) {
    .about-card,
    .about-card::before,
    .about-email,
    .about-friends__link {
        transition: none !important;
        transform: none !important;
    }
}