/* ==================== CSS Reset & Variables ==================== */
:root {
    --primary: #6366f1;
    --primary-light: #818cf8;
    --primary-dark: #4f46e5;
    --primary-bg: #eef2ff;
    --success: #10b981;
    --success-bg: #ecfdf5;
    --danger: #ef4444;
    --danger-bg: #fef2f2;
    --warning: #f59e0b;
    --warning-bg: #fffbeb;
    --gray-50: #f9fafb;
    --gray-100: #f3f4f6;
    --gray-200: #e5e7eb;
    --gray-300: #d1d5db;
    --gray-400: #9ca3af;
    --gray-500: #6b7280;
    --gray-600: #4b5563;
    --gray-700: #374151;
    --gray-800: #1f2937;
    --gray-900: #111827;
    --radius: 12px;
    --radius-sm: 8px;
    --shadow-sm: 0 1px 2px rgba(0,0,0,0.05);
    --shadow: 0 1px 3px rgba(0,0,0,0.1), 0 1px 2px rgba(0,0,0,0.06);
    --shadow-md: 0 4px 6px -1px rgba(0,0,0,0.1), 0 2px 4px -1px rgba(0,0,0,0.06);
    --shadow-lg: 0 10px 15px -3px rgba(0,0,0,0.1), 0 4px 6px -2px rgba(0,0,0,0.05);
    --transition: all 0.2s ease;
}

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

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'PingFang SC', 'Hiragino Sans GB', 'Microsoft YaHei', sans-serif;
    background: var(--gray-50);
    color: var(--gray-800);
    line-height: 1.6;
    min-height: 100vh;
}

/* ==================== Header ==================== */
.header {
    background: white;
    border-bottom: 1px solid var(--gray-200);
    position: sticky;
    top: 0;
    z-index: 100;
    box-shadow: var(--shadow-sm);
}

.header-inner {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 24px;
    height: 64px;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.logo {
    font-size: 20px;
    font-weight: 700;
    color: var(--primary);
}

.nav {
    display: flex;
    gap: 4px;
}

.nav-btn {
    padding: 8px 16px;
    border: none;
    background: transparent;
    color: var(--gray-600);
    font-size: 14px;
    font-weight: 500;
    cursor: pointer;
    border-radius: var(--radius-sm);
    transition: var(--transition);
}

.nav-btn:hover {
    background: var(--gray-100);
    color: var(--gray-800);
}

.nav-btn.active {
    background: var(--primary-bg);
    color: var(--primary);
}

/* ==================== Pages ==================== */
.page {
    display: none;
    max-width: 1200px;
    margin: 0 auto;
    padding: 24px;
}

.page.active {
    display: block;
}

/* ==================== Hero ==================== */
.hero {
    text-align: center;
    padding: 60px 20px 40px;
}

.hero h2 {
    font-size: 32px;
    font-weight: 700;
    color: var(--gray-900);
    margin-bottom: 12px;
}

.hero > p {
    font-size: 16px;
    color: var(--gray-500);
    margin-bottom: 40px;
}

.hero-stats {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 16px;
    margin-bottom: 40px;
}

.stat-card {
    background: white;
    padding: 24px;
    border-radius: var(--radius);
    box-shadow: var(--shadow);
    text-align: center;
    transition: var(--transition);
}

.stat-card:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

.stat-number {
    font-size: 28px;
    font-weight: 700;
    color: var(--primary);
}

.stat-label {
    font-size: 13px;
    color: var(--gray-500);
    margin-top: 4px;
}

/* ==================== Mode Cards ==================== */
.mode-section {
    margin-top: 20px;
}

.mode-section h3 {
    font-size: 20px;
    font-weight: 600;
    margin-bottom: 20px;
    text-align: center;
}

.mode-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 16px;
}

.mode-card {
    background: white;
    padding: 32px 24px;
    border-radius: var(--radius);
    box-shadow: var(--shadow);
    text-align: center;
    cursor: pointer;
    transition: var(--transition);
    border: 2px solid transparent;
}

.mode-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-lg);
    border-color: var(--primary);
}

.mode-icon {
    font-size: 40px;
    margin-bottom: 12px;
}

.mode-card h4 {
    font-size: 16px;
    font-weight: 600;
    margin-bottom: 8px;
    color: var(--gray-800);
}

.mode-card p {
    font-size: 13px;
    color: var(--gray-500);
}

/* ==================== Buttons ==================== */
.btn {
    padding: 10px 20px;
    border: none;
    border-radius: var(--radius-sm);
    font-size: 14px;
    font-weight: 500;
    cursor: pointer;
    transition: var(--transition);
    display: inline-flex;
    align-items: center;
    gap: 8px;
}

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

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

.btn-secondary {
    background: var(--gray-100);
    color: var(--gray-700);
}

.btn-secondary:hover {
    background: var(--gray-200);
}

.btn-ghost {
    background: transparent;
    color: var(--gray-600);
}

.btn-ghost:hover {
    background: var(--gray-100);
}

.btn-large {
    padding: 14px 32px;
    font-size: 16px;
    border-radius: var(--radius);
}

.btn-small {
    padding: 6px 12px;
    font-size: 12px;
}

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

.btn-danger:hover {
    background: #dc2626;
}

.btn-option {
    padding: 16px 24px;
    background: white;
    border: 2px solid var(--gray-200);
    border-radius: var(--radius);
    font-size: 16px;
    cursor: pointer;
    transition: var(--transition);
    flex: 1;
    text-align: center;
}

.btn-option:hover {
    border-color: var(--primary);
    background: var(--primary-bg);
}

.btn-option.selected {
    border-color: var(--primary);
    background: var(--primary-bg);
    color: var(--primary);
    font-weight: 600;
}

.btn-option.correct {
    border-color: var(--success);
    background: var(--success-bg);
    color: var(--success);
}

.btn-option.wrong {
    border-color: var(--danger);
    background: var(--danger-bg);
    color: var(--danger);
}

/* ==================== Practice ==================== */
.setup-panel {
    max-width: 500px;
    margin: 40px auto;
    background: white;
    padding: 40px;
    border-radius: var(--radius);
    box-shadow: var(--shadow-md);
}

.setup-panel h2 {
    text-align: center;
    margin-bottom: 24px;
}

.setup-form .form-group {
    margin-bottom: 20px;
}

.setup-form label {
    display: block;
    font-size: 14px;
    font-weight: 500;
    color: var(--gray-700);
    margin-bottom: 6px;
}

.setup-form select,
.setup-form input[type="number"],
.setup-form input[type="text"],
.setup-form textarea {
    width: 100%;
    padding: 10px 14px;
    border: 1px solid var(--gray-300);
    border-radius: var(--radius-sm);
    font-size: 14px;
    transition: var(--transition);
    background: white;
}

.setup-form select:focus,
.setup-form input:focus,
.setup-form textarea:focus {
    outline: none;
    border-color: var(--primary);
    box-shadow: 0 0 0 3px rgba(99, 102, 241, 0.1);
}

.setup-form .btn {
    width: 100%;
    justify-content: center;
}

/* Progress bar */
.progress-bar-container {
    margin-bottom: 24px;
}

.progress-info {
    display: flex;
    align-items: center;
    gap: 12px;
    margin-bottom: 8px;
}

.progress-bar {
    width: 100%;
    height: 8px;
    background: var(--gray-200);
    border-radius: 4px;
    overflow: hidden;
}

.progress-fill {
    height: 100%;
    background: linear-gradient(90deg, var(--primary), var(--primary-light));
    border-radius: 4px;
    transition: width 0.3s ease;
}

/* Question card */
.question-card {
    background: white;
    border-radius: var(--radius);
    box-shadow: var(--shadow-md);
    padding: 32px;
    margin-bottom: 20px;
}

.question-header {
    display: flex;
    align-items: center;
    gap: 12px;
    margin-bottom: 20px;
}

.question-number {
    font-size: 14px;
    color: var(--gray-500);
    font-weight: 500;
}

.question-type-badge {
    font-size: 12px;
    padding: 4px 10px;
    border-radius: 20px;
    font-weight: 500;
}

.badge {
    display: inline-block;
    padding: 2px 10px;
    border-radius: 20px;
    font-size: 12px;
    font-weight: 500;
}

.badge-choice { background: #dbeafe; color: #2563eb; }
.badge-judge { background: #fef3c7; color: #d97706; }
.badge-short { background: #ede9fe; color: #7c3aed; }

.question-text {
    font-size: 18px;
    font-weight: 500;
    color: var(--gray-900);
    line-height: 1.8;
}

/* Choice options */
.choice-options {
    display: flex;
    flex-direction: column;
    gap: 12px;
    margin-top: 24px;
}

.choice-option-btn {
    display: flex;
    align-items: center;
    gap: 14px;
    padding: 14px 18px;
    background: white;
    border: 2px solid var(--gray-200);
    border-radius: var(--radius-sm);
    cursor: pointer;
    transition: var(--transition);
    text-align: left;
    width: 100%;
    font-size: 15px;
}

.choice-option-btn:hover {
    border-color: var(--primary);
    background: var(--primary-bg);
}

.choice-option-btn .option-label {
    width: 32px;
    height: 32px;
    border-radius: 50%;
    background: var(--gray-100);
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 600;
    font-size: 14px;
    color: var(--gray-600);
    flex-shrink: 0;
}

.choice-option-btn.selected .option-label {
    background: var(--primary);
    color: white;
}

.choice-option-btn.correct {
    border-color: var(--success);
    background: var(--success-bg);
}

.choice-option-btn.correct .option-label {
    background: var(--success);
    color: white;
}

.choice-option-btn.wrong {
    border-color: var(--danger);
    background: var(--danger-bg);
}

.choice-option-btn.wrong .option-label {
    background: var(--danger);
    color: white;
}

/* Judge options */
.judge-options {
    display: flex;
    gap: 16px;
    margin-top: 24px;
}

/* Short answer */
.short-answer {
    margin-top: 24px;
}

.short-answer textarea {
    width: 100%;
    padding: 14px;
    border: 2px solid var(--gray-200);
    border-radius: var(--radius-sm);
    font-size: 15px;
    resize: vertical;
    font-family: inherit;
    line-height: 1.6;
}

.short-answer textarea:focus {
    outline: none;
    border-color: var(--primary);
    box-shadow: 0 0 0 3px rgba(99, 102, 241, 0.1);
}

.short-answer .btn {
    margin-top: 12px;
}

/* Answer panel */
.answer-panel {
    background: white;
    border-radius: var(--radius);
    box-shadow: var(--shadow-md);
    padding: 24px;
    margin-bottom: 20px;
}

.answer-header {
    padding: 12px 16px;
    border-radius: var(--radius-sm);
    margin-bottom: 16px;
    font-weight: 600;
}

.answer-correct .answer-header {
    background: var(--success-bg);
    color: var(--success);
}

.answer-wrong .answer-header {
    background: var(--danger-bg);
    color: var(--danger);
}

.answer-body {
    padding: 16px;
    background: var(--gray-50);
    border-radius: var(--radius-sm);
    margin-bottom: 16px;
    font-size: 14px;
    line-height: 1.8;
}

.answer-body strong {
    color: var(--primary);
}

/* Result */
.practice-result {
    padding: 40px 0;
}

.result-card {
    background: white;
    border-radius: var(--radius);
    box-shadow: var(--shadow-lg);
    padding: 48px;
    text-align: center;
    max-width: 600px;
    margin: 0 auto;
}

.result-card h2 {
    font-size: 28px;
    margin-bottom: 32px;
    color: var(--gray-900);
}

.result-summary {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 16px;
    margin-bottom: 32px;
}

.result-item {
    padding: 20px;
    background: var(--gray-50);
    border-radius: var(--radius-sm);
}

.result-label {
    display: block;
    font-size: 13px;
    color: var(--gray-500);
    margin-bottom: 4px;
}

.result-value {
    font-size: 24px;
    font-weight: 700;
    color: var(--primary);
}

.result-chart {
    margin-bottom: 32px;
}

.result-actions {
    display: flex;
    gap: 12px;
    justify-content: center;
}

/* ==================== Bank Management ==================== */
.bank-container {
    max-width: 900px;
    margin: 0 auto;
}

.bank-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-bottom: 24px;
}

.bank-header h2 {
    font-size: 24px;
}

.bank-actions {
    display: flex;
    gap: 8px;
}

/* ==================== Document Import Area ==================== */
.doc-import-area {
    border: 2px dashed var(--gray-300);
    border-radius: var(--radius);
    padding: 48px 24px;
    text-align: center;
    cursor: pointer;
    transition: var(--transition);
    position: relative;
    margin-bottom: 32px;
    background: white;
}

.doc-import-area:hover,
.doc-import-area.drag-over {
    border-color: var(--primary);
    background: var(--primary-bg);
    transform: none;
}

.doc-import-area.has-file {
    border-color: var(--success);
    background: var(--success-bg);
}

.doc-import-area.processing {
    pointer-events: none;
    opacity: 0.7;
}

.doc-import-icon {
    font-size: 48px;
    margin-bottom: 12px;
}

.doc-import-area h3 {
    font-size: 18px;
    font-weight: 600;
    color: var(--gray-800);
    margin-bottom: 8px;
}

.doc-import-area > p {
    font-size: 14px;
    color: var(--gray-500);
}

.doc-import-hint {
    font-size: 12px !important;
    color: var(--gray-400) !important;
    margin-top: 4px;
}

.doc-import-area input[type="file"] {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    opacity: 0;
    cursor: pointer;
}

/* Hide file input when preview is shown, so buttons can be clicked */
.doc-import-area.has-file input[type="file"],
.doc-import-area.processing input[type="file"] {
    display: none;
}

#bank-upload-status {
    margin-top: 12px;
    font-size: 13px;
}

.upload-success {
    color: var(--success);
    font-weight: 500;
}

.upload-error {
    color: var(--danger);
}

.upload-loading {
    color: var(--primary);
}

.upload-preview-mini {
    margin-top: 12px;
    text-align: left;
    padding: 12px;
    background: white;
    border: 1px solid var(--gray-200);
    border-radius: var(--radius-sm);
    max-height: 200px;
    overflow-y: auto;
}

.bank-list {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(250px, 1fr));
    gap: 16px;
    margin-bottom: 32px;
}

.bank-item {
    background: white;
    padding: 20px;
    border-radius: var(--radius);
    box-shadow: var(--shadow);
    cursor: pointer;
    transition: var(--transition);
    border: 2px solid transparent;
}

.bank-item:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

.bank-item.active {
    border-color: var(--primary);
    background: var(--primary-bg);
}

.bank-item-name {
    font-size: 16px;
    font-weight: 600;
    margin-bottom: 8px;
}

.bank-item-meta {
    display: flex;
    gap: 16px;
    font-size: 13px;
    color: var(--gray-500);
}

.bank-item-actions {
    display: flex;
    gap: 8px;
    margin-top: 12px;
}

/* Questions list */
.questions-section {
    background: white;
    border-radius: var(--radius);
    box-shadow: var(--shadow);
    padding: 24px;
}

.questions-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-bottom: 20px;
}

.filter-bar {
    display: flex;
    gap: 8px;
}

.filter-bar select,
.filter-bar input {
    padding: 8px 12px;
    border: 1px solid var(--gray-300);
    border-radius: var(--radius-sm);
    font-size: 13px;
}

.filter-bar select:focus,
.filter-bar input:focus {
    outline: none;
    border-color: var(--primary);
}

.questions-list {
    max-height: 600px;
    overflow-y: auto;
}

.question-item {
    padding: 16px;
    border-bottom: 1px solid var(--gray-100);
    transition: var(--transition);
}

.question-item:hover {
    background: var(--gray-50);
}

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

.question-item-header {
    display: flex;
    align-items: center;
    gap: 8px;
    margin-bottom: 8px;
}

.question-item-text {
    font-size: 14px;
    color: var(--gray-800);
    line-height: 1.6;
}

.question-item-footer {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-top: 8px;
}

.question-item-actions {
    display: flex;
    gap: 8px;
}

.question-item-actions button {
    padding: 4px 10px;
    font-size: 12px;
    border: none;
    border-radius: 4px;
    cursor: pointer;
    transition: var(--transition);
}

/* ==================== Stats ==================== */
.stats-container {
    max-width: 900px;
    margin: 0 auto;
}

.stats-container > h2 {
    font-size: 24px;
    margin-bottom: 24px;
}

.stats-overview {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 16px;
    margin-bottom: 32px;
}

.stat-card-large {
    background: white;
    padding: 24px;
    border-radius: var(--radius);
    box-shadow: var(--shadow);
    display: flex;
    align-items: center;
    gap: 16px;
}

.stat-icon {
    font-size: 32px;
}

.stat-number-large {
    font-size: 24px;
    font-weight: 700;
    color: var(--gray-900);
}

.stat-label-large {
    font-size: 13px;
    color: var(--gray-500);
}

.chart-section {
    background: white;
    padding: 24px;
    border-radius: var(--radius);
    box-shadow: var(--shadow);
    margin-bottom: 24px;
}

.chart-section h3 {
    margin-bottom: 16px;
}

.chart-container {
    height: 200px;
    display: flex;
    align-items: flex-end;
    gap: 8px;
    padding: 0 8px;
}

.chart-bar-group {
    flex: 1;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 4px;
}

.chart-bar {
    width: 100%;
    max-width: 40px;
    border-radius: 4px 4px 0 0;
    background: linear-gradient(to top, var(--primary), var(--primary-light));
    transition: height 0.3s ease;
    min-height: 4px;
}

.chart-bar-label {
    font-size: 11px;
    color: var(--gray-500);
}

.chart-bar-value {
    font-size: 11px;
    color: var(--gray-700);
    font-weight: 500;
}

/* Type stats */
.type-stats-section {
    background: white;
    padding: 24px;
    border-radius: var(--radius);
    box-shadow: var(--shadow);
    margin-bottom: 24px;
}

.type-stats-section h3 {
    margin-bottom: 16px;
}

.type-stats-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 16px;
}

.type-stat-card {
    padding: 20px;
    border-radius: var(--radius-sm);
    text-align: center;
}

.type-stat-card.choice { background: #dbeafe; }
.type-stat-card.judge { background: #fef3c7; }
.type-stat-card.short { background: #ede9fe; }

.type-stat-number {
    font-size: 28px;
    font-weight: 700;
    margin-bottom: 4px;
}

.type-stat-card.choice .type-stat-number { color: #2563eb; }
.type-stat-card.judge .type-stat-number { color: #d97706; }
.type-stat-card.short .type-stat-number { color: #7c3aed; }

.type-stat-label {
    font-size: 13px;
    color: var(--gray-600);
}

/* Wrong section */
.wrong-section {
    background: white;
    padding: 24px;
    border-radius: var(--radius);
    box-shadow: var(--shadow);
}

.wrong-section h3 {
    margin-bottom: 16px;
}

.wrong-list {
    max-height: 400px;
    overflow-y: auto;
}

.wrong-item {
    padding: 16px;
    border-bottom: 1px solid var(--gray-100);
}

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

.empty-text {
    text-align: center;
    padding: 40px;
    color: var(--gray-400);
    font-size: 14px;
}

/* ==================== Modal ==================== */
.modal {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: 200;
    display: flex;
    align-items: center;
    justify-content: center;
}

.modal.hidden {
    display: none;
}

.modal-overlay {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.5);
}

.modal-content {
    position: relative;
    background: white;
    border-radius: var(--radius);
    width: 90%;
    max-width: 560px;
    max-height: 80vh;
    overflow-y: auto;
    box-shadow: var(--shadow-lg);
}

.modal-large {
    max-width: 720px;
}

.modal-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 20px 24px;
    border-bottom: 1px solid var(--gray-200);
}

.modal-header h3 {
    font-size: 18px;
    font-weight: 600;
}

.modal-close {
    width: 32px;
    height: 32px;
    border: none;
    background: var(--gray-100);
    border-radius: 50%;
    font-size: 20px;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--gray-500);
    transition: var(--transition);
}

.modal-close:hover {
    background: var(--gray-200);
}

.modal-body {
    padding: 24px;
}

.modal-footer {
    display: flex;
    justify-content: flex-end;
    gap: 8px;
    padding: 16px 24px;
    border-top: 1px solid var(--gray-200);
}

/* Import tabs */
.import-tabs {
    display: flex;
    gap: 4px;
    margin-bottom: 20px;
    background: var(--gray-100);
    padding: 4px;
    border-radius: var(--radius-sm);
}

.tab-btn {
    flex: 1;
    padding: 8px 16px;
    border: none;
    background: transparent;
    font-size: 14px;
    font-weight: 500;
    cursor: pointer;
    border-radius: 6px;
    transition: var(--transition);
    color: var(--gray-600);
}

.tab-btn.active {
    background: white;
    color: var(--primary);
    box-shadow: var(--shadow-sm);
}

.tab-btn:hover:not(.active) {
    color: var(--gray-800);
}

.import-panel {
    display: none;
}

.import-panel.active {
    display: block;
}

.help-text {
    font-size: 13px;
    color: var(--gray-500);
    margin-bottom: 12px;
}

.code-example {
    background: var(--gray-900);
    color: #e5e7eb;
    padding: 16px;
    border-radius: var(--radius-sm);
    font-size: 12px;
    line-height: 1.6;
    overflow-x: auto;
    margin-bottom: 16px;
}

.code-example.small {
    font-size: 11px;
    padding: 12px;
}

.csv-example {
    width: 100%;
    border-collapse: collapse;
    font-size: 12px;
    margin-bottom: 16px;
}

.csv-example th,
.csv-example td {
    border: 1px solid var(--gray-300);
    padding: 8px;
    text-align: left;
}

.csv-example th {
    background: var(--gray-100);
    font-weight: 600;
}

/* File upload */
.file-upload {
    border: 2px dashed var(--gray-300);
    border-radius: var(--radius);
    padding: 40px;
    text-align: center;
    cursor: pointer;
    transition: var(--transition);
    position: relative;
}

.file-upload:hover {
    border-color: var(--primary);
    background: var(--primary-bg);
}

.upload-icon {
    font-size: 36px;
    margin-bottom: 8px;
}

.file-upload p {
    font-size: 14px;
    color: var(--gray-500);
}

.file-upload input[type="file"] {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    opacity: 0;
    cursor: pointer;
}

.file-upload.has-file {
    border-color: var(--success);
    background: var(--success-bg);
}

/* ==================== Toast ==================== */
.toast-container {
    position: fixed;
    top: 80px;
    right: 24px;
    z-index: 300;
    display: flex;
    flex-direction: column;
    gap: 8px;
}

.toast {
    padding: 12px 20px;
    border-radius: var(--radius-sm);
    font-size: 14px;
    font-weight: 500;
    box-shadow: var(--shadow-md);
    animation: slideIn 0.3s ease;
    max-width: 320px;
}

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

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

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

@keyframes slideIn {
    from {
        transform: translateX(100%);
        opacity: 0;
    }
    to {
        transform: translateX(0);
        opacity: 1;
    }
}

/* ==================== Form Group ==================== */
.form-group {
    margin-bottom: 16px;
}

.form-group label {
    display: block;
    font-size: 14px;
    font-weight: 500;
    color: var(--gray-700);
    margin-bottom: 6px;
}

.form-group select,
.form-group input,
.form-group textarea {
    width: 100%;
    padding: 10px 14px;
    border: 1px solid var(--gray-300);
    border-radius: var(--radius-sm);
    font-size: 14px;
    transition: var(--transition);
    font-family: inherit;
}

.form-group select:focus,
.form-group input:focus,
.form-group textarea:focus {
    outline: none;
    border-color: var(--primary);
    box-shadow: 0 0 0 3px rgba(99, 102, 241, 0.1);
}

/* ==================== Hidden ==================== */
.hidden {
    display: none !important;
}

/* ==================== Wrong Review ==================== */
.wrong-review-item {
    padding: 16px;
    border: 1px solid var(--gray-200);
    border-radius: var(--radius-sm);
    margin-bottom: 12px;
}

.wrong-review-q {
    font-size: 15px;
    font-weight: 500;
    margin-bottom: 8px;
}

.wrong-review-detail {
    font-size: 13px;
    color: var(--gray-600);
    line-height: 1.8;
}

.wrong-review-detail .your-ans {
    color: var(--danger);
}

.wrong-review-detail .correct-ans {
    color: var(--success);
}

/* ==================== Responsive ==================== */
@media (max-width: 768px) {
    .header-inner {
        flex-direction: column;
        height: auto;
        padding: 12px 16px;
        gap: 8px;
    }

    .nav {
        width: 100%;
        justify-content: center;
    }

    .hero-stats {
        grid-template-columns: repeat(2, 1fr);
    }

    .mode-grid {
        grid-template-columns: repeat(2, 1fr);
    }

    .stats-overview {
        grid-template-columns: repeat(2, 1fr);
    }

    .result-summary {
        grid-template-columns: repeat(2, 1fr);
    }

    .result-actions {
        flex-direction: column;
    }

    .bank-header {
        flex-direction: column;
        gap: 12px;
    }

    .bank-actions {
        flex-wrap: wrap;
    }

    .questions-header {
        flex-direction: column;
        gap: 12px;
    }

    .filter-bar {
        width: 100%;
    }

    .filter-bar input {
        flex: 1;
    }

    .type-stats-grid {
        grid-template-columns: 1fr;
    }

    .modal-content {
        width: 95%;
    }

    .judge-options {
        flex-direction: column;
    }
}

@media (max-width: 480px) {
    .hero h2 {
        font-size: 24px;
    }

    .question-text {
        font-size: 16px;
    }

    .question-card {
        padding: 20px;
    }

    .setup-panel {
        padding: 24px;
    }
}

/* ==================== Scrollbar ==================== */
::-webkit-scrollbar {
    width: 6px;
}

::-webkit-scrollbar-track {
    background: transparent;
}

::-webkit-scrollbar-thumb {
    background: var(--gray-300);
    border-radius: 3px;
}

::-webkit-scrollbar-thumb:hover {
    background: var(--gray-400);
}

/* ==================== Result pie chart CSS ==================== */
.pie-chart {
    width: 160px;
    height: 160px;
    border-radius: 50%;
    margin: 0 auto 16px;
    position: relative;
    display: flex;
    align-items: center;
    justify-content: center;
}

.pie-chart-center {
    width: 80px;
    height: 80px;
    border-radius: 50%;
    background: white;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    position: absolute;
}

.pie-chart-center .value {
    font-size: 24px;
    font-weight: 700;
    color: var(--primary);
}

.pie-chart-center .label {
    font-size: 11px;
    color: var(--gray-500);
}

/* ==================== Drag & Drop ==================== */
.file-upload.drag-over {
    border-color: var(--primary);
    background: var(--primary-bg);
    transform: scale(1.02);
}

@keyframes spin {
    from { transform: rotate(0deg); }
    to { transform: rotate(360deg); }
}