:root {
    /* Base colors */
    --bg-primary: #0a0a0f;
    --bg-secondary: #12121a;
    --bg-tertiary: #1a1a25;
    --bg-card: rgba(26, 26, 37, 0.6);
    
    /* Text colors */
    --text-primary: #e8e8ed;
    --text-secondary: #a0a0b0;
    --text-muted: #6b6b7b;
    
    /* Accent colors - Cyber Blue */
    --accent-primary: #00d4ff;
    --accent-secondary: #0099cc;
    --accent-glow: rgba(0, 212, 255, 0.4);
    
    /* Border */
    --border-color: rgba(255, 255, 255, 0.08);
    --border-hover: rgba(0, 212, 255, 0.3);
    
    /* Status colors */
    --color-success: #00ff9d;
    --color-warning: #ffb800;
    --color-error: #ff4757;
    
    /* Fonts */
    --font-mono: 'JetBrains Mono', monospace;
    --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
    
    /* Spacing */
    --container-max: 1200px;
    --border-radius: 12px;
    --border-radius-sm: 8px;
}

/* Theme: Light */
[data-theme="light"] {
    --bg-primary: #f5f5f7;
    --bg-secondary: #ffffff;
    --bg-tertiary: #e8e8ec;
    --bg-card: rgba(255, 255, 255, 0.8);
    
    --text-primary: #1a1a2e;
    --text-secondary: #4a4a5e;
    --text-muted: #7a7a8e;
    
    --accent-primary: #0066cc;
    --accent-secondary: #004499;
    --accent-glow: rgba(0, 102, 204, 0.3);
    
    --border-color: rgba(0, 0, 0, 0.08);
    --border-hover: rgba(0, 102, 204, 0.3);
}

/* Theme: Cyberpunk */
[data-theme="cyber"] {
    --bg-primary: #0d0221;
    --bg-secondary: #1a0b2e;
    --bg-tertiary: #260f4a;
    --bg-card: rgba(38, 15, 74, 0.6);
    
    --text-primary: #ff00ff;
    --text-secondary: #cc00cc;
    --text-muted: #990099;
    
    --accent-primary: #ff00ff;
    --accent-secondary: #00ffff;
    --accent-glow: rgba(255, 0, 255, 0.5);
    
    --border-color: rgba(255, 0, 255, 0.2);
    --border-hover: rgba(0, 255, 255, 0.5);
}

/* Theme: Matrix */
[data-theme="matrix"] {
    --bg-primary: #000000;
    --bg-secondary: #0a0a0a;
    --bg-tertiary: #111111;
    --bg-card: rgba(0, 255, 65, 0.05);
    
    --text-primary: #00ff41;
    --text-secondary: #00cc33;
    --text-muted: #009922;
    
    --accent-primary: #00ff41;
    --accent-secondary: #00cc33;
    --accent-glow: rgba(0, 255, 65, 0.4);
    
    --border-color: rgba(0, 255, 65, 0.15);
    --border-hover: rgba(0, 255, 65, 0.4);
}

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

body {
    font-family: var(--font-sans);
    background: var(--bg-primary);
    color: var(--text-primary);
    line-height: 1.6;
    min-height: 100vh;
    position: relative;
    overflow-x: hidden;
}

/* Background Effects */
.bg-grid {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-image: 
        linear-gradient(rgba(0, 212, 255, 0.03) 1px, transparent 1px),
        linear-gradient(90deg, rgba(0, 212, 255, 0.03) 1px, transparent 1px);
    background-size: 50px 50px;
    pointer-events: none;
    z-index: -2;
}

[data-theme="light"] .bg-grid {
    background-image: 
        linear-gradient(rgba(0, 102, 204, 0.05) 1px, transparent 1px),
        linear-gradient(90deg, rgba(0, 102, 204, 0.05) 1px, transparent 1px);
}

[data-theme="cyber"] .bg-grid {
    background-image: 
        linear-gradient(rgba(255, 0, 255, 0.05) 1px, transparent 1px),
        linear-gradient(90deg, rgba(0, 255, 255, 0.05) 1px, transparent 1px);
}

[data-theme="matrix"] .bg-grid {
    background-image: 
        linear-gradient(rgba(0, 255, 65, 0.1) 1px, transparent 1px),
        linear-gradient(90deg, rgba(0, 255, 65, 0.1) 1px, transparent 1px);
}

.bg-glow {
    position: fixed;
    top: 20%;
    left: 50%;
    transform: translateX(-50%);
    width: 800px;
    height: 600px;
    background: radial-gradient(ellipse, var(--accent-glow) 0%, transparent 70%);
    pointer-events: none;
    z-index: -1;
    opacity: 0.5;
}

/* Container */
.container {
    max-width: var(--container-max);
    margin: 0 auto;
    padding: 0 24px;
}

/* Header */
.header {
    background: linear-gradient(180deg, var(--bg-secondary) 0%, transparent 100%);
    border-bottom: 1px solid var(--border-color);
    padding: 24px 0;
    position: relative;
}

.header::before {
    content: '';
    position: absolute;
    bottom: -1px;
    left: 0;
    right: 0;
    height: 1px;
    background: linear-gradient(90deg, transparent, var(--accent-primary), transparent);
    opacity: 0.5;
}

.header-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: 20px;
}

.logo-section {
    display: flex;
    align-items: center;
    gap: 16px;
}

.logo-icon {
    font-size: 2.5rem;
    color: var(--accent-primary);
    text-shadow: 0 0 20px var(--accent-glow);
    animation: pulse 2s ease-in-out infinite;
}

@keyframes pulse {
    0%, 100% { opacity: 1; }
    50% { opacity: 0.7; }
}

.logo {
    font-family: var(--font-mono);
    font-size: 1.5rem;
    font-weight: 700;
    letter-spacing: 2px;
    background: linear-gradient(135deg, var(--text-primary), var(--accent-primary));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.tagline {
    color: var(--text-secondary);
    font-size: 0.875rem;
    margin-top: 4px;
}

.header-controls {
    display: flex;
    align-items: center;
    gap: 24px;
}

/* Theme Switcher */
.theme-switcher {
    display: flex;
    gap: 8px;
    padding: 4px;
    background: var(--bg-tertiary);
    border-radius: var(--border-radius);
    border: 1px solid var(--border-color);
}

.theme-btn {
    width: 36px;
    height: 36px;
    border: none;
    background: transparent;
    border-radius: var(--border-radius-sm);
    cursor: pointer;
    transition: all 0.3s ease;
    font-size: 1rem;
    display: flex;
    align-items: center;
    justify-content: center;
}

.theme-btn:hover {
    background: var(--bg-card);
    transform: translateY(-2px);
}

.theme-btn.active {
    background: var(--accent-primary);
    box-shadow: 0 0 15px var(--accent-glow);
}

/* Navigation */
.nav {
    display: flex;
    gap: 16px;
}

.nav-link {
    display: flex;
    align-items: center;
    gap: 6px;
    color: var(--text-secondary);
    text-decoration: none;
    font-size: 0.875rem;
    font-weight: 500;
    padding: 8px 16px;
    border-radius: var(--border-radius-sm);
    transition: all 0.3s ease;
    border: 1px solid transparent;
}

.nav-link:hover {
    color: var(--accent-primary);
    border-color: var(--border-hover);
    background: var(--bg-card);
}

.nav-icon {
    font-size: 0.75rem;
    color: var(--accent-primary);
}

/* Header Meta */
.header-meta {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 12px;
    margin-top: 16px;
    padding-top: 16px;
    border-top: 1px solid var(--border-color);
}

.last-updated {
    font-family: var(--font-mono);
    font-size: 0.8rem;
    color: var(--text-muted);
}

.pulse-indicator {
    width: 8px;
    height: 8px;
    background: var(--color-success);
    border-radius: 50%;
    box-shadow: 0 0 10px var(--color-success);
    animation: blink 1.5s ease-in-out infinite;
}

@keyframes blink {
    0%, 100% { opacity: 1; transform: scale(1); }
    50% { opacity: 0.5; transform: scale(0.8); }
}

/* Main */
.main {
    padding: 40px 0;
}

/* Date Selector */
.date-selector {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 16px;
    margin-bottom: 48px;
    padding: 20px;
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius);
    backdrop-filter: blur(10px);
}

.selector-label {
    display: flex;
    align-items: center;
    gap: 8px;
    color: var(--text-secondary);
    font-weight: 500;
}

.tech-select {
    background: var(--bg-secondary);
    color: var(--text-primary);
    border: 1px solid var(--border-color);
    padding: 10px 16px;
    border-radius: var(--border-radius-sm);
    font-family: var(--font-mono);
    font-size: 0.9rem;
    cursor: pointer;
    min-width: 180px;
    transition: all 0.3s ease;
}

.tech-select:hover,
.tech-select:focus {
    border-color: var(--accent-primary);
    box-shadow: 0 0 10px var(--accent-glow);
    outline: none;
}

/* Sections */
.section {
    margin-bottom: 64px;
}

.section-header {
    display: flex;
    align-items: center;
    gap: 16px;
    margin-bottom: 32px;
}

.section-icon-wrapper {
    width: 48px;
    height: 48px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: var(--border-radius);
    background: var(--bg-card);
    border: 1px solid var(--border-color);
}

.section-icon-wrapper svg {
    width: 24px;
    height: 24px;
}

.github-icon {
    color: var(--text-primary);
}

.twitter-icon {
    color: var(--text-primary);
}

.section-title {
    font-family: var(--font-mono);
    font-size: 1.5rem;
    font-weight: 700;
    display: flex;
    align-items: center;
    gap: 12px;
}

.section-subtitle {
    font-size: 0.875rem;
    color: var(--accent-primary);
    font-weight: 500;
    padding: 4px 12px;
    background: var(--bg-tertiary);
    border-radius: 20px;
    border: 1px solid var(--border-color);
}

.section-line {
    flex: 1;
    height: 1px;
    background: linear-gradient(90deg, var(--border-color), transparent);
}

/* Loading State */
.loading-state {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    padding: 80px;
    gap: 16px;
    color: var(--text-secondary);
}

.loading-spinner {
    width: 40px;
    height: 40px;
    border: 3px solid var(--border-color);
    border-top-color: var(--accent-primary);
    border-radius: 50%;
    animation: spin 1s linear infinite;
}

@keyframes spin {
    to { transform: rotate(360deg); }
}

/* GitHub Cards */
.github-list {
    display: grid;
    gap: 16px;
}

.github-card {
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius);
    padding: 24px;
    transition: all 0.3s ease;
    position: relative;
    overflow: hidden;
}

.github-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 2px;
    background: linear-gradient(90deg, var(--accent-primary), transparent);
    opacity: 0;
    transition: opacity 0.3s ease;
}

.github-card:hover {
    transform: translateY(-2px);
    border-color: var(--border-hover);
    box-shadow: 0 10px 40px rgba(0, 0, 0, 0.3);
}

.github-card:hover::before {
    opacity: 1;
}

.github-header {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    margin-bottom: 12px;
}

.github-rank {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 32px;
    height: 32px;
    background: linear-gradient(135deg, var(--accent-primary), var(--accent-secondary));
    color: var(--bg-primary);
    font-family: var(--font-mono);
    font-weight: 700;
    border-radius: var(--border-radius-sm);
    font-size: 0.875rem;
}

.github-stars {
    display: flex;
    align-items: center;
    gap: 6px;
    color: var(--color-warning);
    font-weight: 600;
    font-size: 0.875rem;
    font-family: var(--font-mono);
}

.github-name {
    font-size: 1.125rem;
    font-weight: 600;
    margin-bottom: 8px;
}

.github-name a {
    color: var(--text-primary);
    text-decoration: none;
    transition: color 0.3s ease;
}

.github-name a:hover {
    color: var(--accent-primary);
}

.github-desc {
    color: var(--text-secondary);
    line-height: 1.6;
    font-size: 0.9rem;
}

.github-meta {
    display: flex;
    gap: 16px;
    margin-top: 16px;
    font-size: 0.8rem;
    color: var(--text-muted);
}

.github-lang {
    display: flex;
    align-items: center;
    gap: 6px;
}

.lang-color {
    width: 10px;
    height: 10px;
    border-radius: 50%;
}

/* Twitter Section */
.twitter-header-info {
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius);
    padding: 20px;
    margin-bottom: 24px;
}

.twitter-title-main {
    font-size: 1.25rem;
    font-weight: 600;
    margin-bottom: 8px;
}

.twitter-timestamp {
    color: var(--text-muted);
    font-size: 0.875rem;
    font-family: var(--font-mono);
}

.hot-topics {
    margin-bottom: 32px;
}

.hot-topics-title {
    display: flex;
    align-items: center;
    gap: 8px;
    color: var(--color-warning);
    font-size: 1rem;
    font-weight: 600;
    margin-bottom: 16px;
}

.topic-list {
    display: flex;
    flex-wrap: wrap;
    gap: 12px;
}

.topic-tag {
    background: rgba(255, 184, 0, 0.1);
    color: var(--color-warning);
    padding: 8px 16px;
    border-radius: 20px;
    font-size: 0.85rem;
    font-weight: 500;
    border: 1px solid rgba(255, 184, 0, 0.2);
    transition: all 0.3s ease;
}

.topic-tag:hover {
    background: rgba(255, 184, 0, 0.2);
    transform: translateY(-1px);
}

.tweet-list {
    display: grid;
    gap: 16px;
}

.tweet-card {
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius);
    padding: 20px;
    transition: all 0.3s ease;
}

.tweet-card:hover {
    border-color: var(--border-hover);
    transform: translateX(4px);
}

.tweet-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 12px;
}

.tweet-author {
    font-weight: 600;
    color: var(--accent-primary);
    font-family: var(--font-mono);
}

.tweet-time {
    color: var(--text-muted);
    font-size: 0.8rem;
}

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

.tweet-link {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    color: var(--accent-primary);
    text-decoration: none;
    font-size: 0.85rem;
    font-weight: 500;
    transition: all 0.3s ease;
}

.tweet-link:hover {
    text-decoration: underline;
    gap: 10px;
}

.tweet-stats {
    display: flex;
    gap: 16px;
    margin-top: 12px;
    font-size: 0.8rem;
    color: var(--text-muted);
    font-family: var(--font-mono);
}

/* Footer */
.footer {
    background: var(--bg-secondary);
    border-top: 1px solid var(--border-color);
    padding: 32px 0;
    margin-top: 64px;
}

.footer-content {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 16px;
    text-align: center;
}

.footer-brand {
    display: flex;
    align-items: center;
    gap: 12px;
    font-weight: 600;
    font-size: 1.1rem;
}

.footer-logo {
    font-size: 1.5rem;
    color: var(--accent-primary);
}

.footer-links {
    display: flex;
    gap: 24px;
}

.footer-link {
    display: flex;
    align-items: center;
    gap: 6px;
    color: var(--text-secondary);
    text-decoration: none;
    font-size: 0.875rem;
    transition: all 0.3s ease;
}

.footer-link:hover {
    color: var(--accent-primary);
}

.footer-link svg {
    width: 16px;
    height: 16px;
}

.footer-info {
    color: var(--text-muted);
    font-size: 0.8rem;
    font-family: var(--font-mono);
}

/* Responsive */
@media (max-width: 768px) {
    .header-content {
        flex-direction: column;
        text-align: center;
    }
    
    .header-controls {
        flex-direction: column;
        width: 100%;
    }
    
    .theme-switcher {
        order: -1;
    }
    
    .nav {
        width: 100%;
        justify-content: center;
    }
    
    .section-title {
        font-size: 1.25rem;
    }
    
    .github-header {
        flex-direction: column;
        gap: 12px;
    }
    
    .date-selector {
        flex-direction: column;
    }
}

/* Scrollbar */
::-webkit-scrollbar {
    width: 8px;
    height: 8px;
}

::-webkit-scrollbar-track {
    background: var(--bg-secondary);
}

::-webkit-scrollbar-thumb {
    background: var(--border-color);
    border-radius: 4px;
}

::-webkit-scrollbar-thumb:hover {
    background: var(--accent-primary);
}