/* Reset and Base Styles */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    --primary-color: #4f46e5;
    --primary-hover: #4338ca;
    --secondary-color: #6b7280;
    --success-color: #10b981;
    --warning-color: #f59e0b;
    --danger-color: #ef4444;
    --background: #f9fafb;
    --card-background: #ffffff;
    --text-primary: #111827;
    --text-secondary: #6b7280;
    --border-color: #e5e7eb;
    --shadow: 0 1px 3px 0 rgba(0, 0, 0, 0.1), 0 1px 2px 0 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);
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Roboto', 'Helvetica', 'Arial', sans-serif;
    background-color: var(--background);
    color: var(--text-primary);
    line-height: 1.6;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 1.5rem;
    width: 100%;
}

/* Navigation */
.navbar {
    background-color: var(--card-background);
    box-shadow: var(--shadow);
    position: sticky;
    top: 0;
    z-index: 100;
}

.navbar .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1rem 1.5rem;
}

.nav-brand a {
    font-size: 1.5rem;
    font-weight: bold;
    color: var(--primary-color);
    text-decoration: none;
}

.nav-links {
    display: flex;
    gap: 1.5rem;
    align-items: center;
}

.nav-links a {
    color: var(--text-secondary);
    text-decoration: none;
    font-weight: 500;
    transition: color 0.2s;
}

.nav-links a:hover {
    color: var(--primary-color);
}

.btn-logout {
    padding: 0.5rem 1rem;
    background-color: var(--danger-color);
    color: white !important;
    border-radius: 0.375rem;
}

.btn-logout:hover {
    background-color: #dc2626;
}

/* Flash Messages */
.flash-message {
    padding: 1rem;
    margin-bottom: 1rem;
}

.flash-message.success {
    background-color: #d1fae5;
    color: #065f46;
    border-left: 4px solid var(--success-color);
}

.flash-message.error {
    background-color: #fee2e2;
    color: #991b1b;
    border-left: 4px solid var(--danger-color);
}

.flash-message.info {
    background-color: #dbeafe;
    color: #1e40af;
    border-left: 4px solid var(--primary-color);
}

/* Main Content */
.main-content {
    flex: 1;
    padding: 2rem 0;
}

/* Footer */
.footer {
    background-color: var(--card-background);
    border-top: 1px solid var(--border-color);
    padding: 1.5rem 0;
    margin-top: auto;
    text-align: center;
    color: var(--text-secondary);
    font-size: 0.875rem;
}

/* Buttons */
.btn-primary {
    background-color: var(--primary-color);
    color: white;
    padding: 0.625rem 1.25rem;
    border: none;
    border-radius: 0.375rem;
    font-size: 1rem;
    font-weight: 500;
    cursor: pointer;
    transition: background-color 0.2s;
    text-decoration: none;
    display: inline-block;
}

.btn-primary:hover:not(:disabled) {
    background-color: var(--primary-hover);
}

.btn-primary:disabled {
    opacity: 0.5;
    cursor: not-allowed;
}

.btn-secondary {
    background-color: var(--secondary-color);
    color: white;
    padding: 0.625rem 1.25rem;
    border: none;
    border-radius: 0.375rem;
    font-size: 1rem;
    font-weight: 500;
    cursor: pointer;
    transition: background-color 0.2s;
    text-decoration: none;
    display: inline-block;
}

.btn-secondary:hover:not(:disabled) {
    background-color: #4b5563;
}

.btn-secondary:disabled {
    opacity: 0.5;
    cursor: not-allowed;
}

/* Forms */
.form-group {
    margin-bottom: 1.5rem;
}

.form-group label {
    display: block;
    font-weight: 500;
    margin-bottom: 0.5rem;
    color: var(--text-primary);
}

.form-group input[type="text"],
.form-group input[type="email"],
.form-group input[type="password"],
.form-group input[type="number"],
.form-group select,
.form-group textarea {
    width: 100%;
    padding: 0.625rem;
    border: 1px solid var(--border-color);
    border-radius: 0.375rem;
    font-size: 1rem;
    transition: border-color 0.2s;
}

.form-group input:focus,
.form-group select:focus,
.form-group textarea:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(79, 70, 229, 0.1);
}

.form-group small {
    display: block;
    margin-top: 0.25rem;
    color: var(--text-secondary);
    font-size: 0.875rem;
}

.form-actions {
    display: flex;
    gap: 1rem;
    margin-top: 2rem;
}

/* Checkbox Styles */
.checkbox-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
    gap: 0.75rem;
    margin-top: 0.5rem;
}

.checkbox-label {
    display: flex;
    align-items: center;
    cursor: pointer;
    padding: 0.5rem;
    border-radius: 0.375rem;
    transition: background-color 0.2s;
}

.checkbox-label:hover {
    background-color: var(--background);
}

.checkbox-label input[type="checkbox"] {
    margin-right: 0.5rem;
    cursor: pointer;
}

.checkbox-group {
    margin-bottom: 1rem;
}

/* Auth Pages */
.auth-container {
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 60vh;
    padding: 2rem 0;
}

.auth-box {
    background-color: var(--card-background);
    border-radius: 0.5rem;
    box-shadow: var(--shadow-lg);
    padding: 2.5rem;
    width: 100%;
    max-width: 450px;
}

.auth-box h1 {
    margin-bottom: 1.5rem;
    text-align: center;
    color: var(--primary-color);
}

.auth-form {
    margin-bottom: 1.5rem;
}

.auth-footer {
    text-align: center;
    padding-top: 1rem;
    border-top: 1px solid var(--border-color);
}

.auth-footer a {
    color: var(--primary-color);
    text-decoration: none;
    font-weight: 500;
}

/* Messages */
.error-message {
    background-color: #fee2e2;
    color: #991b1b;
    padding: 1rem;
    border-radius: 0.375rem;
    margin-bottom: 1.5rem;
    border-left: 4px solid var(--danger-color);
}

.success-message {
    background-color: #d1fae5;
    color: #065f46;
    padding: 1rem;
    border-radius: 0.375rem;
    margin-bottom: 1.5rem;
    border-left: 4px solid var(--success-color);
}

.help-text {
    color: var(--text-secondary);
    font-size: 0.875rem;
    margin-bottom: 1rem;
}

/* Profile Page */
.profile-container h1 {
    margin-bottom: 1.5rem;
}

.profile-container h2 {
    margin-top: 2rem;
    margin-bottom: 1rem;
    padding-bottom: 0.5rem;
    border-bottom: 2px solid var(--border-color);
    color: var(--primary-color);
}

.profile-form {
    background-color: var(--card-background);
    padding: 2rem;
    border-radius: 0.5rem;
    box-shadow: var(--shadow);
}

/* Dictionary Page */
.dictionary-container h1 {
    margin-bottom: 1.5rem;
}

.dictionary-filters {
    background-color: var(--card-background);
    padding: 1.5rem;
    border-radius: 0.5rem;
    box-shadow: var(--shadow);
    margin-bottom: 2rem;
}

.dictionary-filters h2 {
    margin-bottom: 1rem;
    color: var(--primary-color);
}

.filter-row {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 1rem;
}

.dictionary-results h2 {
    margin-bottom: 1rem;
}

.dictionary-list {
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.dictionary-entry {
    background-color: var(--card-background);
    padding: 1.5rem;
    border-radius: 0.5rem;
    box-shadow: var(--shadow);
}

.entry-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 1rem;
}

.entry-text {
    display: flex;
    align-items: center;
    gap: 1rem;
    font-size: 1.125rem;
}

.source-text {
    font-weight: 600;
}

.arrow {
    color: var(--text-secondary);
}

.target-text {
    font-weight: 600;
    color: var(--primary-color);
}

.entry-type-badge {
    background-color: var(--primary-color);
    color: white;
    padding: 0.25rem 0.75rem;
    border-radius: 9999px;
    font-size: 0.75rem;
    font-weight: 500;
    text-transform: uppercase;
}

.entry-pronunciation {
    margin-bottom: 0.75rem;
    color: var(--text-secondary);
    font-style: italic;
}

.entry-meta {
    margin-top: 1rem;
}

.entry-tags {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

.tag-group {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
    align-items: center;
}

.tag {
    display: inline-block;
    padding: 0.25rem 0.625rem;
    border-radius: 0.25rem;
    font-size: 0.75rem;
    font-weight: 500;
}

.tag-topic {
    background-color: #dbeafe;
    color: #1e40af;
}

.tag-hobby {
    background-color: #d1fae5;
    color: #065f46;
}

.tag-scenario {
    background-color: #fef3c7;
    color: #92400e;
}

.tag-grammar {
    background-color: #e9d5ff;
    color: #6b21a8;
}

.entry-difficulty {
    margin-top: 0.5rem;
    color: var(--text-secondary);
}

.entry-notes {
    margin-top: 0.5rem;
    padding: 0.75rem;
    background-color: var(--background);
    border-radius: 0.375rem;
    font-size: 0.875rem;
}

.pagination {
    display: flex;
    justify-content: center;
    align-items: center;
    gap: 1rem;
    margin-top: 2rem;
}

.page-info {
    color: var(--text-secondary);
}

.no-results {
    text-align: center;
    padding: 3rem 1rem;
    background-color: var(--card-background);
    border-radius: 0.5rem;
    box-shadow: var(--shadow);
}

.no-results p {
    margin-bottom: 0.5rem;
}

/* Flashcards */
.flashcards-container h1 {
    margin-bottom: 1.5rem;
    text-align: center;
}

.flashcards-header {
    margin-bottom: 2rem;
}

.progress-bar {
    width: 100%;
    height: 8px;
    background-color: var(--border-color);
    border-radius: 9999px;
    overflow: hidden;
    margin-bottom: 0.5rem;
}

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

.progress-text {
    text-align: center;
    color: var(--text-secondary);
    font-size: 0.875rem;
}

.flashcard-viewer {
    max-width: 600px;
    margin: 0 auto;
}

.flashcard {
    perspective: 1000px;
    cursor: pointer;
    margin-bottom: 2rem;
}

.flashcard-inner {
    position: relative;
    width: 100%;
    height: 400px;
    transition: transform 0.6s;
    transform-style: preserve-3d;
}

.flashcard.flipped .flashcard-inner {
    transform: rotateY(180deg);
}

.flashcard-front,
.flashcard-back {
    position: absolute;
    width: 100%;
    height: 100%;
    backface-visibility: hidden;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    background-color: var(--card-background);
    border-radius: 0.5rem;
    box-shadow: var(--shadow-lg);
    padding: 2rem;
}

.flashcard-back {
    transform: rotateY(180deg);
}

.card-type-label {
    position: absolute;
    top: 1rem;
    left: 1rem;
    font-size: 0.75rem;
    font-weight: 500;
    color: var(--text-secondary);
    text-transform: uppercase;
}

.card-text {
    font-size: 2rem;
    font-weight: 600;
    text-align: center;
    margin-bottom: 1rem;
}

.card-hint {
    position: absolute;
    bottom: 1rem;
    font-size: 0.875rem;
    color: var(--text-secondary);
    font-style: italic;
}

.card-pronunciation,
.card-notes {
    margin-top: 1rem;
    text-align: center;
    font-size: 0.875rem;
    color: var(--text-secondary);
}

.flashcard-controls {
    display: flex;
    justify-content: center;
    gap: 1rem;
    margin-bottom: 1rem;
}

.btn-need-practice {
    background-color: var(--warning-color);
    color: white;
    padding: 0.625rem 1.25rem;
    border: none;
    border-radius: 0.375rem;
    font-size: 1rem;
    font-weight: 500;
    cursor: pointer;
    transition: background-color 0.2s;
}

.btn-need-practice:hover:not(:disabled) {
    background-color: #d97706;
}

.btn-know-it {
    background-color: var(--success-color);
    color: white;
    padding: 0.625rem 1.25rem;
    border: none;
    border-radius: 0.375rem;
    font-size: 1rem;
    font-weight: 500;
    cursor: pointer;
    transition: background-color 0.2s;
}

.btn-know-it:hover:not(:disabled) {
    background-color: #059669;
}

.btn-flip {
    background-color: var(--primary-color);
    color: white;
    padding: 0.625rem 1.25rem;
    border: none;
    border-radius: 0.375rem;
    font-size: 1rem;
    font-weight: 500;
    cursor: pointer;
    transition: background-color 0.2s;
}

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

.flashcard-navigation {
    display: flex;
    justify-content: center;
    gap: 1rem;
    margin-bottom: 2rem;
}

.flashcard-stats {
    background-color: var(--card-background);
    padding: 1.5rem;
    border-radius: 0.5rem;
    box-shadow: var(--shadow);
    max-width: 600px;
    margin: 0 auto;
}

.flashcard-stats h3 {
    margin-bottom: 1rem;
    text-align: center;
    color: var(--primary-color);
}

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

.stat-item {
    text-align: center;
    padding: 1rem;
    background-color: var(--background);
    border-radius: 0.375rem;
}

.stat-label {
    display: block;
    font-size: 0.875rem;
    color: var(--text-secondary);
    margin-bottom: 0.5rem;
}

.stat-value {
    display: block;
    font-size: 1.5rem;
    font-weight: 600;
}

.stat-success {
    color: var(--success-color);
}

.stat-warning {
    color: var(--warning-color);
}

/* ============================================================================
   TUTOR SESSION STYLES
   ============================================================================ */

/* Session List Page */
.tutor-sessions-page .page-header {
    margin-bottom: 2rem;
}

.tutor-sessions-page .page-description {
    color: var(--text-secondary);
    margin-top: 0.5rem;
}

.session-actions {
    display: flex;
    gap: 1rem;
    margin-bottom: 2rem;
}

.sessions-list h2 {
    margin-bottom: 1rem;
    font-size: 1.25rem;
}

.session-cards {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: 1rem;
}

.session-card {
    background: var(--card-background);
    border-radius: 0.5rem;
    padding: 1rem;
    box-shadow: var(--shadow);
    border-left: 4px solid var(--border-color);
}

.session-card.session-draft { border-left-color: var(--text-secondary); }
.session-card.session-waiting { border-left-color: var(--warning-color); }
.session-card.session-active { border-left-color: var(--success-color); }
.session-card.session-completed { border-left-color: var(--primary-color); }
.session-card.session-cancelled { border-left-color: var(--danger-color); }

.session-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 0.75rem;
}

.session-code {
    font-family: monospace;
    font-size: 1.25rem;
    font-weight: 600;
}

.session-status {
    padding: 0.25rem 0.5rem;
    border-radius: 0.25rem;
    font-size: 0.75rem;
    font-weight: 500;
    text-transform: uppercase;
}

.status-draft { background: #e5e7eb; color: #374151; }
.status-waiting { background: #fef3c7; color: #92400e; }
.status-active { background: #d1fae5; color: #065f46; }
.status-completed { background: #dbeafe; color: #1e40af; }
.status-cancelled { background: #fee2e2; color: #991b1b; }

.session-info {
    margin-bottom: 1rem;
}

.session-info p {
    margin: 0.25rem 0;
    font-size: 0.875rem;
}

.session-waiting {
    color: var(--warning-color);
    font-style: italic;
}

.session-meta {
    color: var(--text-secondary);
    font-size: 0.75rem;
}

.session-actions-row {
    display: flex;
    gap: 0.5rem;
    flex-wrap: wrap;
}

/* Join Page */
.tutor-join-page .join-form-container {
    max-width: 400px;
    margin: 0 auto 2rem;
}

.join-form {
    background: var(--card-background);
    padding: 2rem;
    border-radius: 0.5rem;
    box-shadow: var(--shadow);
}

.code-input {
    font-family: monospace;
    font-size: 2rem;
    text-align: center;
    letter-spacing: 0.5rem;
    text-transform: uppercase;
    padding: 1rem;
}

.code-display {
    background: var(--background);
    border: 2px dashed var(--primary-color);
    border-radius: 0.5rem;
    padding: 1.5rem 2rem;
    margin: 1.5rem 0;
    cursor: pointer;
    transition: all 0.2s;
}

.code-display:hover {
    background: var(--primary-color);
}

.code-display:hover .big-code {
    color: white;
}

.big-code {
    font-family: monospace;
    font-size: 3rem;
    font-weight: bold;
    letter-spacing: 0.5rem;
    color: var(--primary-color);
}

.code-modal {
    max-width: 400px;
}

.join-help {
    max-width: 500px;
    margin: 0 auto;
    padding: 1.5rem;
    background: var(--background);
    border-radius: 0.5rem;
}

.join-help h3 {
    margin-bottom: 1rem;
}

.join-help ol {
    padding-left: 1.5rem;
}

.join-help li {
    margin-bottom: 0.5rem;
}

/* Active Session Page */
.session-header-bar {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 0.75rem 1rem;
    background: var(--card-background);
    border-radius: 0.5rem;
    margin-bottom: 1rem;
    box-shadow: var(--shadow);
}

.session-info-left,
.session-info-right {
    display: flex;
    align-items: center;
    gap: 1rem;
}

.session-code-display {
    font-family: monospace;
}

.session-status-badge {
    padding: 0.25rem 0.5rem;
    border-radius: 0.25rem;
    font-size: 0.75rem;
    font-weight: 500;
}

.connection-status {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    font-size: 0.75rem;
}

.connection-dot {
    width: 8px;
    height: 8px;
    border-radius: 50%;
}

.connection-dot.connected { background: var(--success-color); }
.connection-dot.disconnected { background: var(--danger-color); animation: pulse 1s infinite; }

@keyframes pulse {
    0%, 100% { opacity: 1; }
    50% { opacity: 0.5; }
}

.partner-info {
    color: var(--text-secondary);
    font-size: 0.875rem;
}

.waiting-text {
    color: var(--warning-color);
    font-style: italic;
    font-size: 0.875rem;
}

/* Main Session Layout */
.tutor-session-container {
    display: grid;
    grid-template-columns: 280px 1fr 280px;
    gap: 1rem;
    min-height: calc(100vh - 250px);
}

/* Word Cloud Panel */
.word-cloud-panel {
    background: var(--card-background);
    border-radius: 0.5rem;
    box-shadow: var(--shadow);
    display: flex;
    flex-direction: column;
    max-height: calc(100vh - 250px);
}

.cloud-tabs {
    display: flex;
    border-bottom: 1px solid var(--border-color);
}

.cloud-tab {
    flex: 1;
    padding: 0.75rem;
    text-align: center;
    cursor: pointer;
    border: none;
    background: none;
    border-bottom: 2px solid transparent;
    font-size: 0.875rem;
    transition: all 0.2s;
}

.cloud-tab:hover {
    background: var(--background);
}

.cloud-tab.active {
    border-bottom-color: var(--primary-color);
    color: var(--primary-color);
    font-weight: 500;
}

.cloud-filters {
    padding: 0.75rem;
    border-bottom: 1px solid var(--border-color);
}

.filter-row {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    margin-bottom: 0.5rem;
}

.filter-row:last-child {
    margin-bottom: 0;
}

.filter-row label {
    font-size: 0.75rem;
    color: var(--text-secondary);
    white-space: nowrap;
}

.threshold-buttons {
    display: flex;
    gap: 0.25rem;
}

.threshold-btn {
    padding: 0.25rem 0.5rem;
    font-size: 0.75rem;
    border: 1px solid var(--border-color);
    background: var(--background);
    border-radius: 0.25rem;
    cursor: pointer;
    transition: all 0.2s;
}

.threshold-btn:hover {
    border-color: var(--primary-color);
}

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

.filter-select {
    flex: 1;
    padding: 0.375rem;
    font-size: 0.75rem;
    border: 1px solid var(--border-color);
    border-radius: 0.25rem;
}

.word-cloud-list {
    flex: 1;
    overflow-y: auto;
    padding: 0.75rem;
}

.word-card {
    background: var(--background);
    border: 1px solid var(--border-color);
    border-radius: 0.375rem;
    padding: 0.625rem;
    margin-bottom: 0.5rem;
    cursor: pointer;
    transition: all 0.2s;
}

.word-card:hover {
    border-color: var(--primary-color);
    box-shadow: var(--shadow);
}

.word-card.good {
    border-left: 3px solid var(--success-color);
}

.word-card.bad {
    border-left: 3px solid var(--warning-color);
}

.word-text {
    margin-bottom: 0.25rem;
}

.source-text {
    font-weight: 500;
}

.target-text {
    color: var(--primary-color);
    font-weight: 500;
}

.source-text.small {
    font-size: 0.75rem;
    color: var(--text-secondary);
    font-weight: normal;
    margin-left: 0.25rem;
}

.word-meta {
    display: flex;
    justify-content: space-between;
    font-size: 0.75rem;
}

.mastery-badge {
    padding: 0.125rem 0.375rem;
    background: var(--background);
    border-radius: 0.25rem;
    color: var(--text-secondary);
}

.word-type {
    color: var(--text-secondary);
    text-transform: capitalize;
}

.empty-cloud,
.empty-lesson,
.empty-used {
    text-align: center;
    color: var(--text-secondary);
    padding: 2rem 1rem;
    font-size: 0.875rem;
}

/* Lesson Bar */
.lesson-bar {
    background: var(--card-background);
    border-radius: 0.5rem;
    box-shadow: var(--shadow);
    display: flex;
    flex-direction: column;
    max-height: calc(100vh - 250px);
}

.lesson-bar-header {
    padding: 1rem;
    border-bottom: 1px solid var(--border-color);
}

.lesson-bar-header h3 {
    margin: 0;
    font-size: 1rem;
}

.lesson-words {
    flex: 1;
    overflow-y: auto;
    padding: 1rem;
}

.lesson-word-card {
    background: var(--background);
    border: 1px solid var(--border-color);
    border-radius: 0.375rem;
    padding: 0.75rem;
    margin-bottom: 0.75rem;
}

.word-content {
    margin-bottom: 0.5rem;
}

.teacher-word-view {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.expand-btn {
    width: 24px;
    height: 24px;
    border: 1px solid var(--border-color);
    background: var(--card-background);
    border-radius: 0.25rem;
    cursor: pointer;
    font-size: 1rem;
    line-height: 1;
}

.word-translation {
    margin-top: 0.5rem;
    padding-top: 0.5rem;
    border-top: 1px dashed var(--border-color);
    font-size: 0.875rem;
}

.pronunciation {
    color: var(--text-secondary);
    font-style: italic;
    margin-left: 0.5rem;
}

.word-actions {
    display: flex;
    gap: 0.5rem;
    flex-wrap: wrap;
}

/* Used Bar */
.used-bar {
    background: var(--card-background);
    border-radius: 0.5rem;
    box-shadow: var(--shadow);
    display: flex;
    flex-direction: column;
    max-height: calc(100vh - 250px);
}

.used-bar-header {
    padding: 1rem;
    border-bottom: 1px solid var(--border-color);
}

.used-bar-header h3 {
    margin: 0 0 0.5rem;
    font-size: 1rem;
}

.used-stats {
    display: flex;
    gap: 1rem;
    font-size: 0.75rem;
}

.used-stats .stat.correct {
    color: var(--success-color);
}

.used-stats .stat.incorrect {
    color: var(--danger-color);
}

.used-words {
    flex: 1;
    overflow-y: auto;
    padding: 0.5rem;
}

.used-word {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 0.5rem;
    border-bottom: 1px solid var(--border-color);
    font-size: 0.875rem;
}

.used-word.correct {
    background: rgba(16, 185, 129, 0.1);
}

.used-word.incorrect {
    background: rgba(239, 68, 68, 0.1);
}

.word-result {
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.result-icon {
    width: 20px;
    height: 20px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 0.625rem;
    font-weight: bold;
}

.result-icon.correct-icon {
    background: var(--success-color);
    color: white;
}

.result-icon.incorrect-icon {
    background: var(--danger-color);
    color: white;
}

/* Button Sizes */
.btn-xs {
    padding: 0.25rem 0.5rem;
    font-size: 0.75rem;
}

.btn-sm {
    padding: 0.375rem 0.75rem;
    font-size: 0.875rem;
}

.btn-lg {
    padding: 0.75rem 1.5rem;
    font-size: 1.125rem;
}

.btn-outline {
    background: transparent;
    border: 1px solid var(--border-color);
    color: var(--text-color);
}

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

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

.modal {
    background: var(--card-background);
    border-radius: 0.5rem;
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.2);
    max-width: 500px;
    width: 90%;
    max-height: 90vh;
    overflow: hidden;
}

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

.modal-header h2 {
    margin: 0;
    font-size: 1.25rem;
}

.modal-close {
    background: none;
    border: none;
    font-size: 1.5rem;
    cursor: pointer;
    color: var(--text-secondary);
}

.modal-body {
    padding: 1rem;
}

.modal-footer {
    display: flex;
    justify-content: flex-end;
    gap: 0.5rem;
    padding-top: 1rem;
    border-top: 1px solid var(--border-color);
    margin-top: 1rem;
}

/* Radio Group */
.radio-group {
    display: flex;
    gap: 1rem;
    flex-wrap: wrap;
}

.radio-label {
    display: flex;
    align-items: center;
    gap: 0.375rem;
    cursor: pointer;
}

.checkbox-label {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    cursor: pointer;
}

/* Toast */
.toast {
    position: fixed;
    bottom: 2rem;
    left: 50%;
    transform: translateX(-50%);
    background: var(--text-color);
    color: var(--card-background);
    padding: 0.75rem 1.5rem;
    border-radius: 0.5rem;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.3);
    z-index: 1100;
}

/* Empty State */
.empty-state {
    text-align: center;
    padding: 3rem 2rem;
    color: var(--text-secondary);
}

/* Alpine x-cloak */
[x-cloak] {
    display: none !important;
}

/* Error Message */
.error-message {
    background: #fee2e2;
    color: #991b1b;
    padding: 0.75rem;
    border-radius: 0.375rem;
    margin-bottom: 1rem;
    font-size: 0.875rem;
}

/* Responsive Design */
@media (max-width: 768px) {
    .nav-links {
        gap: 1rem;
    }

    .filter-row {
        grid-template-columns: 1fr;
    }

    .checkbox-grid {
        grid-template-columns: 1fr;
    }

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

    .flashcard-inner {
        height: 350px;
    }

    .card-text {
        font-size: 1.5rem;
    }

    .flashcard-controls {
        flex-direction: column;
    }

    /* Tutor Session Responsive */
    .tutor-session-container {
        grid-template-columns: 1fr;
        gap: 1rem;
    }

    .word-cloud-panel,
    .lesson-bar,
    .used-bar {
        max-height: none;
    }

    .session-header-bar {
        flex-direction: column;
        gap: 0.75rem;
        align-items: flex-start;
    }

    .session-info-right {
        width: 100%;
        justify-content: space-between;
    }

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

    .session-cards {
        grid-template-columns: 1fr;
    }
}