/* Dark Mode Styles */
:root {
    --bg-primary: #ffffff;
    --bg-secondary: #f8f9fa;
    --text-primary: #1e293b;
    --text-secondary: #64748b;
    --border-color: #e2e8f0;
    --card-bg: #ffffff;
}

.dark-mode {
    --bg-primary: #0f172a;
    --bg-secondary: #1e293b;
    --text-primary: #f1f5f9;
    --text-secondary: #94a3b8;
    --border-color: #334155;
    --card-bg: #1e293b;
}

.dark-mode body {
    background-color: var(--bg-primary);
    color: var(--text-primary);
}

.dark-mode .article-item,
.dark-mode .card {
    background-color: var(--card-bg);
    border-color: var(--border-color);
}

.dark-mode a {
    color: #60a5fa;
}

.dark-mode .article-meta {
    color: var(--text-secondary);
}

/* Dark Mode Toggle Button */
.dark-mode-toggle {
    position: fixed;
    bottom: 24px;
    right: 24px;
    width: 56px;
    height: 56px;
    border-radius: 50%;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    border: none;
    cursor: pointer;
    box-shadow: 0 4px 12px rgba(0,0,0,0.15);
    z-index: 1000;
    transition: transform 0.2s;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 24px;
}

.dark-mode-toggle:hover {
    transform: scale(1.1);
}

.dark-mode-toggle .light-icon {
    display: none;
}

.dark-mode .dark-mode-toggle .dark-icon {
    display: none;
}

.dark-mode .dark-mode-toggle .light-icon {
    display: block;
}