:root {
    --bg-primary: #ffffff;
    --bg-secondary: #f5f5f5;
    --card-bg: #ffffff;
    --input-bg: #ffffff;
    --text-primary: #333333;
    --text-secondary: #666666;
    --text-tertiary: #999999;
    --border-color: #e0e0e0;
}

[data-theme="dark"] {
    --bg-primary: #1a1a1a;
    --bg-secondary: #2d2d2d;
    --card-bg: #2d2d2d;
    --input-bg: #3d3d3d;
    --text-primary: #ffffff;
    --text-secondary: #cccccc;
    --text-tertiary: #999999;
    --border-color: #444444;
}

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

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
    background: var(--bg-primary);
    color: var(--text-primary);
    transition: background 0.3s, color 0.3s;
}

/* Smooth transitions for theme changes */
body, .header, .card, .btn, input, .upload-area, .photo-card, .stat-card, .member-card, .logs-section {
    transition: background 0.3s, color 0.3s, border-color 0.3s;
}