/* Light Theme (Default) */
[data-theme="light"] {
    --bg-color: #f5f7fa;
    --text-color: #333;
    --card-bg: white;
    --border-color: #e0e0e0;
}

/* Dark Theme */
[data-theme="dark"] {
    --bg-color: #1a1a1a;
    --text-color: #f0f0f0;
    --card-bg: #2d2d2d;
    --border-color: #444;
}

/* Apply theme colors */
body {
    background-color: var(--bg-color);
    color: var(--text-color);
}

.app-header,
.controls-section,
.preview-section,
.history-section {
    background-color: var(--card-bg);
    border: 1px solid var(--border-color);
}

.control-group label {
    color: var(--text-color);
}

.qr-preview-container {
    background-color: var(--bg-color);
}

/* Theme toggle button */
.theme-toggle {
    position: fixed;
    bottom: 20px;
    right: 20px;
    width: 50px;
    height: 50px;
    border-radius: 50%;
    background-color: var(--primary-color);
    color: white;
    display: flex;
    justify-content: center;
    align-items: center;
    cursor: pointer;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.2);
    z-index: 100;
    border: none;
    font-size: 20px;
}

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