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

:root {
    --primary: #4a6de5;
    --primary-dark: #3a5bd5;
    --secondary: #e54a6d;
    --light: #f4f7fe;
    --dark: #2c3e50;
    --success: #2ecc71;
    --warning: #f1c40f;
    --danger: #e74c3c;
    --border-radius: 8px;
    --shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
    --transition: all 0.3s ease;
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background-color: var(--light);
    color: var(--dark);
    min-height: 100vh;
}

#app {
    max-width: 1200px;
    margin: 0 auto;
    padding: 20px;
}

.app-container {
    background-color: #fff;
    border-radius: var(--border-radius);
    box-shadow: var(--shadow);
    overflow: hidden;
}

.header {
    background-color: var(--primary);
    color: white;
    padding: 20px;
    text-align: center;
}

.header h1 {
    margin-bottom: 10px;
    font-size: 2rem;
}

.header p {
    opacity: 0.9;
}

.tabs {
    display: flex;
    background-color: var(--primary-dark);
}

.tab {
    flex: 1;
    padding: 15px;
    text-align: center;
    color: white;
    cursor: pointer;
    transition: var(--transition);
    border-bottom: 3px solid transparent;
}

.tab:hover {
    background-color: rgba(255, 255, 255, 0.1);
}

.tab.active {
    background-color: rgba(255, 255, 255, 0.2);
    border-bottom: 3px solid white;
}

.tab-content {
    padding: 20px;
    min-height: 400px;
}

/* Form styles */
.form-group {
    margin-bottom: 15px;
}

.form-group label {
    display: block;
    margin-bottom: 5px;
    font-weight: 500;
}

.form-control {
    width: 100%;
    padding: 10px;
    border: 1px solid #ddd;
    border-radius: var(--border-radius);
    font-size: 1rem;
}

.btn {
    padding: 10px 20px;
    border: none;
    border-radius: var(--border-radius);
    cursor: pointer;
    font-size: 1rem;
    transition: var(--transition);
    display: inline-block;
}

.btn-primary {
    background-color: var(--primary);
    color: white;
}

.btn-primary:hover {
    background-color: var(--primary-dark);
}

.btn-secondary {
    background-color: var(--secondary);
    color: white;
}

.btn-secondary:hover {
    background-color: #d43a5d;
}

.btn-success {
    background-color: var(--success);
    color: white;
}

.btn-warning {
    background-color: var(--warning);
    color: white;
}

.btn-danger {
    background-color: var(--danger);
    color: white;
}

/* Answer tab */
.answer-container {
    text-align: center;
    max-width: 600px;
    margin: 0 auto;
}

.answer-name {
    font-size: 2.5rem;
    margin: 40px 0;
    animation: fadeIn 0.5s;
}

.answer-buttons {
    display: flex;
    justify-content: space-between;
    margin-bottom: 30px;
}

.answer-buttons button {
    flex: 1;
    margin: 0 5px;
    padding: 15px;
    font-size: 1rem;
}

.don't-know {
    background-color: var(--danger);
}

.heard-of {
    background-color: var(--warning);
}

.know-them {
    background-color: var(--success);
}

.progress-bar {
    background-color: #eee;
    height: 10px;
    border-radius: 5px;
    margin-bottom: 20px;
    overflow: hidden;
}

.progress {
    height: 100%;
    background-color: var(--primary);
    width: 0%;
    transition: width 0.3s ease;
}

/* Sets tab */
.sets-container {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: 20px;
}

.set-card {
    background-color: white;
    border-radius: var(--border-radius);
    box-shadow: var(--shadow);
    padding: 20px;
    transition: var(--transition);
}

.set-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 6px 12px rgba(0, 0, 0, 0.15);
}

.set-card h3 {
    margin-bottom: 10px;
    color: var(--primary);
}

.set-card .meta {
    display: flex;
    justify-content: space-between;
    margin-bottom: 15px;
    font-size: 0.9rem;
    color: #666;
}

.filter-controls {
    display: flex;
    justify-content: space-between;
    margin-bottom: 20px;
    flex-wrap: wrap;
}

.search-box {
    flex: 1;
    margin-right: 20px;
}

.sort-controls {
    display: flex;
}

.sort-controls button {
    margin-left: 5px;
}

/* Leaderboard tab */
.leaderboard-nav {
    display: flex;
    margin-bottom: 20px;
    border-bottom: 1px solid #ddd;
}

.leaderboard-nav button {
    padding: 10px 15px;
    background: none;
    border: none;
    cursor: pointer;
    font-size: 1rem;
    transition: var(--transition);
    border-bottom: 3px solid transparent;
}

.leaderboard-nav button.active {
    color: var(--primary);
    border-bottom: 3px solid var(--primary);
}

.leaderboard-table {
    width: 100%;
    border-collapse: collapse;
}

.leaderboard-table th,
.leaderboard-table td {
    padding: 12px 15px;
    text-align: left;
    border-bottom: 1px solid #ddd;
}

.leaderboard-table th {
    background-color: var(--primary);
    color: white;
}

.leaderboard-table tr:nth-child(even) {
    background-color: #f9f9f9;
}

.leaderboard-table tr:hover {
    background-color: #f1f1f1;
}

.rank {
    font-weight: bold;
    text-align: center;
}

/* Animations */
@keyframes fadeIn {
    from { opacity: 0; }
    to { opacity: 1; }
}

.fade-in {
    animation: fadeIn 0.5s;
}

/* Responsive design */
@media (max-width: 768px) {
    .tabs {
        flex-direction: column;
    }
    
    .answer-buttons {
        flex-direction: column;
    }
    
    .answer-buttons button {
        margin: 5px 0;
    }
    
    .filter-controls {
        flex-direction: column;
    }
    
    .search-box {
        margin-right: 0;
        margin-bottom: 10px;
    }
}

/* Other custom components */
.name-list {
    max-height: 300px;
    overflow-y: auto;
    border: 1px solid #ddd;
    border-radius: var(--border-radius);
    margin-bottom: 20px;
    padding: 10px;
}

.name-item {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 8px;
    border-bottom: 1px solid #eee;
}

.name-item:last-child {
    border-bottom: none;
}

.name-item button {
    background: none;
    border: none;
    color: var(--danger);
    cursor: pointer;
}

.set-builder {
    display: flex;
    gap: 20px;
}

.set-builder .column {
    flex: 1;
}

.message {
    text-align: center;
    padding: 20px;
    animation: fadeIn 0.5s;
}

.loading {
    text-align: center;
    padding: 40px;
    font-size: 1.2rem;
    color: #666;
}

.confirmation-modal {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background-color: rgba(0, 0, 0, 0.5);
    display: flex;
    justify-content: center;
    align-items: center;
    z-index: 1000;
}

.modal-content {
    background-color: white;
    padding: 20px;
    border-radius: var(--border-radius);
    max-width: 400px;
    width: 100%;
}

.modal-actions {
    display: flex;
    justify-content: flex-end;
    margin-top: 20px;
}

.modal-actions button {
    margin-left: 10px;
}