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

:root {
    --primary-color: #2563eb;
    --secondary-color: #1e40af;
    --bg-color: #f8fafc;
    --card-bg: #ffffff;
    --text-primary: #1e293b;
    --text-secondary: #64748b;
    --border-color: #e2e8f0;
    --hover-color: #f1f5f9;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Roboto', 'Oxygen',
        'Ubuntu', 'Cantarell', 'Fira Sans', 'Droid Sans', 'Helvetica Neue', sans-serif;
    line-height: 1.6;
    color: var(--text-primary);
    background-color: var(--bg-color);
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 20px;
}

/* Header */
header {
    text-align: center;
    padding: 40px 0;
    border-bottom: 2px solid var(--border-color);
    margin-bottom: 30px;
}

header h1 {
    font-size: 2.5rem;
    color: var(--primary-color);
    margin-bottom: 10px;
}

.subtitle {
    font-size: 1.1rem;
    color: var(--text-secondary);
    margin-bottom: 15px;
}

.last-updated {
    font-size: 0.9rem;
    color: var(--text-secondary);
}

/* Controls */
.controls {
    background: var(--card-bg);
    padding: 20px;
    border-radius: 8px;
    margin-bottom: 20px;
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.1);
}

.search-box {
    margin-bottom: 20px;
}

.search-box input {
    width: 100%;
    padding: 12px 16px;
    font-size: 1rem;
    border: 1px solid var(--border-color);
    border-radius: 6px;
    outline: none;
    transition: border-color 0.2s;
}

.search-box input:focus {
    border-color: var(--primary-color);
}

.filters {
    margin-bottom: 20px;
}

.filters label {
    display: block;
    margin-bottom: 10px;
    font-weight: 500;
}

.filter-buttons {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
}

.filter-btn {
    padding: 8px 16px;
    border: 2px solid var(--border-color);
    background: var(--card-bg);
    border-radius: 20px;
    cursor: pointer;
    transition: all 0.2s;
    font-size: 0.9rem;
    display: inline-flex;
    align-items: center;
    gap: 6px;
}

.filter-btn img {
    width: 16px;
    height: 16px;
    object-fit: contain;
    padding: 2px;
    background: white;
    border-radius: 50%;
    box-shadow: 0 1px 2px rgba(0, 0, 0, 0.1);
}

.article-count-badge {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-width: 20px;
    height: 20px;
    padding: 0 6px;
    margin-left: 6px;
    background: rgba(255, 255, 255, 0.3);
    border-radius: 10px;
    font-size: 0.75rem;
    font-weight: 600;
    color: rgba(0, 0, 0, 0.6);
}

.filter-btn.active .article-count-badge {
    background: rgba(255, 255, 255, 0.9);
    color: rgba(0, 0, 0, 0.8);
}

.filter-btn:hover {
    background: var(--hover-color);
    transform: translateY(-1px);
}

.filter-btn.active {
    color: white;
    border-width: 2px;
    box-shadow: 0 4px 8px rgba(0, 0, 0, 0.2), inset 0 2px 4px rgba(0, 0, 0, 0.1);
    transform: translateY(0px);
}

/* Active 'All' button */
.filter-btn[data-source="all"].active {
    background: var(--primary-color);
    border-color: var(--primary-color);
}

/* Active filter button colors */
.filter-btn.active.source-google-research,
.filter-btn.active.source-google-ai,
.filter-btn.active.source-google-blog-ai {
    background: #4285F4 !important;
    border-color: #4285F4 !important;
}

.filter-btn.active.source-nvidia-blog,
.filter-btn.active.source-nvidia-news {
    background: #76B900 !important;
    border-color: #76B900 !important;
}

.filter-btn.active.source-microsoft-research,
.filter-btn.active.source-microsoft-ai-news {
    background: #00A4EF !important;
    border-color: #00A4EF !important;
}

.filter-btn.active.source-anthropic {
    background: #D97757 !important;
    border-color: #D97757 !important;
}

.filter-btn.active.source-meta-ai {
    background: #0668E1 !important;
    border-color: #0668E1 !important;
}

.filter-btn.active.source-google-deepmind {
    background: #4285F4 !important;
    border-color: #4285F4 !important;
}

.filter-btn.active.source-lg-ai-research {
    background: #A50034 !important;
    border-color: #A50034 !important;
}

.filter-btn.active.source-openai {
    background: #10A37F !important;
    border-color: #10A37F !important;
}

.filter-btn.active.source-xai {
    background: #000000 !important;
    border-color: #000000 !important;
}

.filter-btn.active.source-deepseek,
.filter-btn.active.source-deepseek-blog {
    background: #4D6BFE !important;
    border-color: #4D6BFE !important;
}

.filter-btn.active.source-qwen {
    background: #6952EF !important;
    border-color: #6952EF !important;
}

/* Inactive filter button background colors (lighter shade) */
.filter-btn.source-google-research,
.filter-btn.source-google-ai,
.filter-btn.source-google-blog-ai {
    background: #4285F420;
    border-color: #4285F460;
}

.filter-btn.source-nvidia-blog,
.filter-btn.source-nvidia-news {
    background: #76B90020;
    border-color: #76B90060;
}

.filter-btn.source-microsoft-research,
.filter-btn.source-microsoft-ai-news {
    background: #00A4EF20;
    border-color: #00A4EF60;
}

.filter-btn.source-anthropic {
    background: #D9775720;
    border-color: #D9775760;
}

.filter-btn.source-meta-ai {
    background: #0668E120;
    border-color: #0668E160;
}

.filter-btn.source-google-deepmind {
    background: #4285F420;
    border-color: #4285F460;
}

.filter-btn.source-lg-ai-research {
    background: #A5003420;
    border-color: #A5003460;
}

.filter-btn.source-openai {
    background: #10A37F20;
    border-color: #10A37F60;
}

.filter-btn.source-xai {
    background: #00000020;
    border-color: #00000060;
}

.filter-btn.source-deepseek,
.filter-btn.source-deepseek-blog {
    background: #4D6BFE20;
    border-color: #4D6BFE60;
}

.filter-btn.source-qwen {
    background: #6952EF20;
    border-color: #6952EF60;
}

.sort-options {
    display: flex;
    align-items: center;
    gap: 10px;
}

.sort-options select {
    padding: 8px 12px;
    border: 1px solid var(--border-color);
    border-radius: 6px;
    font-size: 0.95rem;
    cursor: pointer;
    outline: none;
}

/* Stats */
.stats {
    margin-bottom: 20px;
    padding: 10px 0;
    color: var(--text-secondary);
    font-size: 0.95rem;
}

/* Articles */
.articles {
    display: grid;
    gap: 20px;
}

.loading {
    text-align: center;
    padding: 40px;
    color: var(--text-secondary);
}

.article-card {
    background: var(--card-bg);
    padding: 24px;
    border-radius: 8px;
    border: 1px solid var(--border-color);
    transition: all 0.2s;
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.1);
}

.article-card:hover {
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
    transform: translateY(-2px);
}

.article-header {
    margin-bottom: 12px;
    display: flex;
    align-items: center;
    gap: 12px;
    flex-wrap: wrap;
}

.article-source {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 6px 14px;
    color: white;
    border-radius: 16px;
    font-size: 0.85rem;
    font-weight: 500;
}

.article-source img {
    width: 20px;
    height: 20px;
    object-fit: contain;
    padding: 3px;
    background: white;
    border-radius: 50%;
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.15);
}

/* Company-specific colors for article badges */
.article-source.source-google-research,
.article-source.source-google-ai,
.article-source.source-google-blog-ai {
    background: #4285F4 !important;
}

.article-source.source-nvidia-blog,
.article-source.source-nvidia-news {
    background: #76B900 !important;
}

.article-source.source-microsoft-research,
.article-source.source-microsoft-ai-news {
    background: #00A4EF !important;
}

.article-source.source-anthropic {
    background: #D97757 !important;
}

.article-source.source-meta-ai {
    background: #0668E1 !important;
}

.article-source.source-google-deepmind {
    background: #4285F4 !important;
}

.article-source.source-lg-ai-research {
    background: #A50034 !important;
}

.article-source.source-openai {
    background: #10A37F !important;
}

.article-source.source-xai {
    background: #000000 !important;
}

.article-source.source-deepseek,
.article-source.source-deepseek-blog {
    background: #4D6BFE !important;
}

.article-source.source-qwen {
    background: #6952EF !important;
}

.article-title {
    font-size: 1.3rem;
    margin-bottom: 8px;
    line-height: 1.4;
}

.article-title a {
    color: var(--text-primary);
    text-decoration: none;
    transition: color 0.2s;
}

.article-title a:hover {
    color: var(--primary-color);
}

.article-meta {
    display: flex;
    gap: 16px;
    font-size: 0.9rem;
    color: var(--text-secondary);
    margin-bottom: 12px;
}

.article-date::before {
    content: "📅 ";
}

.article-summary {
    color: var(--text-secondary);
    line-height: 1.6;
    margin-bottom: 12px;
}

.article-categories {
    display: flex;
    flex-wrap: wrap;
    gap: 6px;
}

.category-tag {
    padding: 4px 10px;
    background: var(--hover-color);
    border-radius: 8px;
    font-size: 0.8rem;
    color: var(--text-secondary);
}

.no-results {
    text-align: center;
    padding: 60px 20px;
    color: var(--text-secondary);
}

.no-results h2 {
    margin-bottom: 10px;
}

/* Footer */
footer {
    margin-top: 60px;
    padding: 30px 0;
    border-top: 2px solid var(--border-color);
    text-align: center;
    color: var(--text-secondary);
    font-size: 0.9rem;
}

footer p {
    margin-bottom: 8px;
}

footer a {
    color: var(--primary-color);
    text-decoration: none;
}

footer a:hover {
    text-decoration: underline;
}

/* Responsive */
@media (max-width: 768px) {
    header h1 {
        font-size: 2rem;
    }

    .controls {
        padding: 15px;
    }

    .filter-buttons {
        gap: 6px;
    }

    .filter-btn {
        font-size: 0.85rem;
        padding: 6px 12px;
    }

    .article-card {
        padding: 16px;
    }

    .article-title {
        font-size: 1.1rem;
    }

    .article-meta {
        flex-direction: column;
        gap: 4px;
    }
}