/* AI News Digest - Styles */

:root {
    --color-primary: #6366F1;
    --color-primary-light: #818CF8;
    --color-primary-dark: #4F46E5;
    --color-bg: #FAFAFA;
    --color-surface: #FFFFFF;
    --color-text: #1A1A2E;
    --color-text-secondary: #6B7280;
    --color-border: #E5E7EB;
    --color-accent: #10B981;
    --radius: 12px;
    --shadow-sm: 0 1px 2px rgba(0,0,0,0.04);
    --shadow-md: 0 4px 12px rgba(0,0,0,0.06);
    --shadow-lg: 0 8px 24px rgba(0,0,0,0.08);
}

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

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    background: var(--color-bg);
    color: var(--color-text);
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
}

.container {
    max-width: 740px;
    margin: 0 auto;
    padding: 2rem 1.5rem;
}

/* Header */
header {
    margin-bottom: 2.5rem;
}

.back-link {
    display: inline-block;
    margin-bottom: 1rem;
    color: var(--color-primary);
    text-decoration: none;
    font-size: 0.875rem;
    font-weight: 500;
}

.back-link:hover {
    color: var(--color-primary-dark);
}

.header-content {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    gap: 1rem;
    flex-wrap: wrap;
}

.logo-section {
    display: flex;
    align-items: center;
    gap: 0.875rem;
}

.logo-icon {
    flex-shrink: 0;
}

h1 {
    font-size: 1.75rem;
    font-weight: 700;
    letter-spacing: -0.02em;
    color: var(--color-text);
    line-height: 1.2;
}

.subtitle {
    color: var(--color-text-secondary);
    font-size: 0.9375rem;
    margin-top: 0.125rem;
}

.badge {
    display: inline-flex;
    align-items: center;
    gap: 0.375rem;
    background: linear-gradient(135deg, #EEF2FF, #E0E7FF);
    color: var(--color-primary-dark);
    font-size: 0.75rem;
    font-weight: 600;
    padding: 0.375rem 0.75rem;
    border-radius: 100px;
    white-space: nowrap;
    border: 1px solid rgba(99, 102, 241, 0.15);
}

.badge::before {
    content: '';
    width: 6px;
    height: 6px;
    border-radius: 50%;
    background: var(--color-accent);
    animation: pulse 2s ease-in-out infinite;
}

@keyframes pulse {
    0%, 100% { opacity: 1; }
    50% { opacity: 0.4; }
}

/* Article Cards */
main {
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.card {
    background: var(--color-surface);
    border: 1px solid var(--color-border);
    border-radius: var(--radius);
    padding: 1.5rem;
    transition: box-shadow 0.2s ease, border-color 0.2s ease;
}

.card:hover {
    box-shadow: var(--shadow-md);
    border-color: var(--color-primary-light);
}

.card-source {
    font-size: 0.75rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    color: var(--color-primary);
    margin-bottom: 0.5rem;
}

.card-title {
    font-size: 1.125rem;
    font-weight: 600;
    line-height: 1.4;
    margin-bottom: 0.75rem;
}

.card-title a {
    color: var(--color-text);
    text-decoration: none;
}

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

.card-summary {
    color: var(--color-text-secondary);
    font-size: 0.9375rem;
    line-height: 1.65;
    margin-bottom: 0.75rem;
}

.card-meta {
    display: flex;
    gap: 1rem;
    align-items: center;
}

.card-date {
    font-size: 0.8125rem;
    color: var(--color-text-secondary);
}

/* Empty State */
.empty-state {
    text-align: center;
    padding: 4rem 2rem;
    color: var(--color-text-secondary);
}

.empty-state p {
    margin-bottom: 0.5rem;
}

/* Archive Section */
.archive-section {
    margin-top: 3rem;
    padding-top: 2rem;
    border-top: 1px solid var(--color-border);
}

.archive-section h2 {
    font-size: 1.125rem;
    font-weight: 600;
    margin-bottom: 1rem;
    color: var(--color-text);
}

.archive-list {
    list-style: none;
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(140px, 1fr));
    gap: 0.5rem;
}

.archive-list li a {
    display: block;
    padding: 0.5rem 0.75rem;
    background: var(--color-surface);
    border: 1px solid var(--color-border);
    border-radius: 8px;
    color: var(--color-text);
    text-decoration: none;
    font-size: 0.875rem;
    font-weight: 500;
    text-align: center;
    transition: all 0.15s ease;
}

.archive-list li a:hover {
    border-color: var(--color-primary);
    color: var(--color-primary);
    box-shadow: var(--shadow-sm);
}

/* Footer */
footer {
    margin-top: 3rem;
    padding-top: 1.5rem;
    border-top: 1px solid var(--color-border);
}

.footer-content {
    text-align: center;
    color: var(--color-text-secondary);
    font-size: 0.8125rem;
    line-height: 1.8;
}

.footer-content a {
    color: var(--color-primary);
    text-decoration: none;
    font-weight: 500;
}

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

/* Responsive */
@media (max-width: 640px) {
    .container {
        padding: 1.25rem 1rem;
    }

    h1 {
        font-size: 1.375rem;
    }

    .header-content {
        flex-direction: column;
    }

    .card {
        padding: 1.25rem;
    }

    .card-title {
        font-size: 1rem;
    }

    .archive-list {
        grid-template-columns: repeat(auto-fill, minmax(120px, 1fr));
    }
}

/* Print-friendly */
@media print {
    body { background: white; }
    .badge, .archive-section, footer { display: none; }
    .card { break-inside: avoid; border: 1px solid #ddd; }
}