/* =====================================
   GLOBAL SETTINGS
===================================== */
:root {
    --ai-bg: #f9fafb;
    --ai-text: #222;
    --ai-subtext: #555;
    --ai-accent: #004e98;
    --ai-border: #e1e4e8;
    --ai-muted-bg: #f1f3f5;
}

body {
    background: var(--ai-bg);
    font-family: "Inter", "Helvetica Neue", Arial, sans-serif;
    color: var(--ai-text);
    line-height: 1.7;
    font-size: 16px;
}

/* 通用 */
a {
    color: var(--ai-accent);
    text-decoration: none;
}

a:hover {
    text-decoration: underline;
}

img {
    display: block;
    width: 100%;
    height: auto;
    border-radius: 2px;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 1rem;
}

/* =====================================
   BANNER + SEARCH
===================================== */
#ai_auto_banner {
    text-align: center;
    padding: 6rem 0 4rem;
    background: #fff;
    border-bottom: 1px solid var(--ai-border);
}

.ai_auto_banner-title {
    font-size: 2.4rem;
    font-weight: 600;
    color: var(--ai-accent);
    margin-bottom: 1rem;
}

.ai_auto_banner-info {
    color: var(--ai-subtext);
    font-size: 1.05rem;
    max-width: 640px;
    margin: 0 auto 2rem;
}

.ai_auto_banner-search .form-control {
    border: 1px solid var(--ai-border);
    border-right: none;
    padding: 0.9rem 1rem;
    font-size: 1rem;
}

.ai_auto_banner-search .btn {
    background: var(--ai-accent);
    color: #fff;
    border: 1px solid var(--ai-accent);
    padding: 0 1.5rem;
    transition: background 0.2s;
}

.ai_auto_banner-search .btn:hover {
    background: #003e7a;
}

/* =====================================
   SECTION TITLES
===================================== */
.ai_auto_section-title {
    font-size: 1.6rem;
    font-weight: 600;
    color: var(--ai-accent);
    border-left: 4px solid var(--ai-accent);
    padding-left: 0.75rem;
    margin: 3rem 0 1.5rem;
}

/* =====================================
   FEATURED ARTICLES - MAGAZINE
===================================== */
.ai_auto_magazine-main {
    background: #fff;
    border: 1px solid var(--ai-border);
    padding: 0;
}

.ai_auto_magazine-main img {
    height: 900px;
    object-fit: cover;
}

.ai_auto_article-img-right {
    height: 100px;
    object-fit: cover;
}

.ai_auto_magazine-main-content {
    padding: 1.2rem 1.5rem 1.5rem;
}

.ai_auto_magazine-main-content h3 {
    font-size: 1.4rem;
    font-weight: 600;
    margin-bottom: 0.6rem;
}

.ai_auto_magazine-main-content p {
    color: var(--ai-subtext);
    font-size: 0.95rem;
    margin-bottom: 0.8rem;
}

.ai_auto_article-meta {
    font-size: 0.85rem;
    color: var(--ai-subtext);
}

.ai_auto_skeuo-element {
    background: #fff;
    border: 1px solid var(--ai-border);
    padding: 0.8rem;
    transition: transform 0.15s ease, box-shadow 0.15s ease;
}

.ai_auto_skeuo-element:hover {
    transform: translateY(-2px);
    box-shadow: 0 2px 6px rgba(0, 0, 0, 0.05);
}

.ai_auto_skeuo-element h5 {
    font-weight: 500;
    margin-top: 0.6rem;
    margin-bottom: 0.4rem;
    color: var(--ai-text);
    font-size: 1.056rem;
}

/* =====================================
   WATERFALL (Latest Articles)
===================================== */
.ai_auto_waterfall-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(340px, 1fr));
    gap: 1.5rem;
}

.ai_auto_waterfall-card {
    background: #fff;
    border: 1px solid var(--ai-border);
    display: flex;
    flex-direction: column;
    transition: transform 0.2s ease;
}

.ai_auto_waterfall-card:hover {
    transform: translateY(-3px);
}

.ai_auto_waterfall-card .bg-primary {
    color: #fff;
}

.ai_auto_waterfall-img {
    height: 200px;
    object-fit: cover;
    border-bottom: 1px solid var(--ai-border);
}

.ai_auto_waterfall-content {
    padding: 1rem 1.2rem;
}

.ai_auto_waterfall-content h4 {
    font-size: 1.1rem;
    font-weight: 600;
    margin-bottom: 0.5rem;
}

.ai_auto_waterfall-content p {
    color: var(--ai-subtext);
    font-size: 0.9rem;
}

/* =====================================
   RECOMMENDED ARTICLES - FUSION GRID
===================================== */
.ai_auto_fusion-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: 1.2rem;
}

.ai_auto_fusion-card {
    position: relative;
    display: block;
    overflow: hidden;
    border: 1px solid var(--ai-border);
    background: #fff;
}

.ai_auto_fusion-img {
    width: 100%;
    height: 180px;
    object-fit: cover;
    transition: transform 0.3s ease;
}

.ai_auto_fusion-card:hover .ai_auto_fusion-img {
    transform: scale(1.05);
}

.ai_auto_fusion-overlay {
    position: absolute;
    inset: 0;
    background: rgba(0, 0, 0, 0.45);
    color: #fff;
    padding: 1rem;
    opacity: 0;
    transition: opacity 0.3s ease;
    display: flex;
    flex-direction: column;
    justify-content: flex-end;
}

.ai_auto_fusion-card:hover .ai_auto_fusion-overlay {
    opacity: 1;
}

.ai_auto_fusion-title {
    font-size: 1.1rem;
    font-weight: 500;
    margin-bottom: 0.5rem;
}

.ai_auto_fusion-meta {
    font-size: 0.85rem;
}

/* =====================================
   TAGS
===================================== */
.badge {
    font-size: 0.75rem;
    font-weight: 500;
    background: var(--ai-muted-bg);
    color: var(--ai-accent);
    border-radius: 3px;
    padding: 0.25rem 0.5rem;
}

.badge.bg-primary {
    background: #e6f0fb;
}

.badge.bg-secondary {
    background: #f0f1f3;
    color: var(--ai-subtext);
}

/* =====================================
   SUBSCRIBE
===================================== */
#ai_auto_subscribe {
    background: #fff;
    border-top: 1px solid var(--ai-border);
    padding: 4rem 0;
    text-align: center;
}

.ai_auto_subscribe-title {
    font-size: 1.6rem;
    color: var(--ai-accent);
    font-weight: 600;
}

.ai_auto_subscribe-info {
    color: var(--ai-subtext);
    font-size: 1rem;
    margin-bottom: 2rem;
}

.ai_auto_subscribe-form .form-control {
    border: 1px solid var(--ai-border);
    border-right: none;
    padding: 0.8rem;
    max-width: 400px;
    margin: 0 auto;
}

.ai_auto_subscribe-form .btn {
    background: var(--ai-accent);
    color: #fff;
    border: 1px solid var(--ai-accent);
    padding: 0 1.5rem;
}

.ai_auto_subscribe-form .btn:hover {
    background: #003e7a;
}

/* =====================================
   RESPONSIVE
===================================== */
@media (max-width: 768px) {
    .ai_auto_banner-title {
        font-size: 2rem;
    }
    .ai_auto_waterfall-grid {
        grid-template-columns: 1fr;
    }
    .ai_auto_fusion-grid {
        grid-template-columns: 1fr;
    }
}