/* ============================================
   Kǒh Nzime - Apprendre le Nzime
   Design System & Styles
   ============================================ */

:root {
    --green-50: #f0fdf4;
    --green-100: #dcfce7;
    --green-200: #bbf7d0;
    --green-300: #86efac;
    --green-400: #4ade80;
    --green-500: #22c55e;
    --green-600: #16a34a;
    --green-700: #15803d;
    --green-800: #166534;
    --green-900: #14532d;

    --white: #ffffff;
    --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;

    --red-400: #f87171;
    --red-500: #ef4444;
    --orange-400: #fb923c;
    --orange-500: #f97316;
    --yellow-400: #facc15;
    --blue-400: #60a5fa;
    --blue-500: #3b82f6;
    --purple-400: #a78bfa;
    --purple-500: #8b5cf6;

    --shadow-sm: 0 1px 2px rgba(0,0,0,0.05);
    --shadow-md: 0 4px 6px -1px rgba(0,0,0,0.1), 0 2px 4px -2px rgba(0,0,0,0.1);
    --shadow-lg: 0 10px 15px -3px rgba(0,0,0,0.1), 0 4px 6px -4px rgba(0,0,0,0.1);
    --shadow-xl: 0 20px 25px -5px rgba(0,0,0,0.1), 0 8px 10px -6px rgba(0,0,0,0.1);

    --radius-sm: 8px;
    --radius-md: 12px;
    --radius-lg: 16px;
    --radius-xl: 24px;
    --radius-full: 9999px;

    --font-family: 'Nunito', -apple-system, BlinkMacSystemFont, sans-serif;
}

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

body {
    font-family: var(--font-family);
    background: var(--gray-50);
    color: var(--gray-800);
    min-height: 100vh;
    overflow-x: hidden;
    -webkit-font-smoothing: antialiased;
}

/* ============================================
   Screen Management
   ============================================ */
.screen {
    display: none;
    min-height: 100vh;
    animation: fadeIn 0.3s ease;
}

.screen.active {
    display: flex;
    flex-direction: column;
}

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(10px); }
    to { opacity: 1; transform: translateY(0); }
}

@keyframes slideUp {
    from { opacity: 0; transform: translateY(30px); }
    to { opacity: 1; transform: translateY(0); }
}

@keyframes popIn {
    0% { transform: scale(0.8); opacity: 0; }
    50% { transform: scale(1.05); }
    100% { transform: scale(1); opacity: 1; }
}

@keyframes shake {
    0%, 100% { transform: translateX(0); }
    20% { transform: translateX(-8px); }
    40% { transform: translateX(8px); }
    60% { transform: translateX(-5px); }
    80% { transform: translateX(5px); }
}

@keyframes bounceIn {
    0% { transform: scale(0); }
    50% { transform: scale(1.15); }
    70% { transform: scale(0.95); }
    100% { transform: scale(1); }
}

@keyframes confetti {
    0% { transform: translateY(0) rotate(0deg); opacity: 1; }
    100% { transform: translateY(-100px) rotate(720deg); opacity: 0; }
}

@keyframes pulse {
    0%, 100% { transform: scale(1); }
    50% { transform: scale(1.05); }
}

@keyframes heartBeat {
    0% { transform: scale(1); }
    15% { transform: scale(1.3); }
    30% { transform: scale(1); }
    45% { transform: scale(1.2); }
    60% { transform: scale(1); }
}

/* ============================================
   Home Screen
   ============================================ */
.home-container {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    min-height: 100vh;
    padding: 2rem;
    background: linear-gradient(135deg, var(--green-600) 0%, var(--green-700) 50%, var(--green-800) 100%);
    position: relative;
    overflow: hidden;
}

.home-container::before {
    content: '';
    position: absolute;
    top: -50%;
    left: -50%;
    width: 200%;
    height: 200%;
    background: radial-gradient(circle at 30% 70%, rgba(255,255,255,0.08) 0%, transparent 50%),
                radial-gradient(circle at 70% 30%, rgba(255,255,255,0.05) 0%, transparent 40%);
    pointer-events: none;
}

.logo-area {
    text-align: center;
    margin-bottom: 3rem;
    position: relative;
    z-index: 1;
}

.logo-icon {
    font-size: 4rem;
    margin-bottom: 1rem;
    animation: bounceIn 0.8s ease;
    filter: drop-shadow(0 4px 8px rgba(0,0,0,0.2));
}

.app-title {
    font-size: 3rem;
    font-weight: 900;
    color: var(--white);
    letter-spacing: -1px;
    text-shadow: 0 2px 10px rgba(0,0,0,0.2);
    margin-bottom: 0.5rem;
}

.app-subtitle {
    font-size: 1.2rem;
    color: var(--green-100);
    font-weight: 600;
    margin-bottom: 0.25rem;
}

.app-description {
    font-size: 0.9rem;
    color: var(--green-200);
    opacity: 0.8;
}

.home-actions {
    display: flex;
    flex-direction: column;
    gap: 1rem;
    width: 100%;
    max-width: 320px;
    position: relative;
    z-index: 1;
}

.home-stats {
    margin-top: 2rem;
    display: flex;
    gap: 2rem;
    position: relative;
    z-index: 1;
}

.stat-item {
    text-align: center;
    color: var(--green-100);
}

.stat-value {
    font-size: 1.5rem;
    font-weight: 800;
    color: var(--white);
}

.stat-label {
    font-size: 0.75rem;
    opacity: 0.8;
}

/* ============================================
   Buttons
   ============================================ */
.btn {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
    padding: 0.875rem 1.5rem;
    border: none;
    border-radius: var(--radius-lg);
    font-family: var(--font-family);
    font-size: 1rem;
    font-weight: 700;
    cursor: pointer;
    transition: all 0.2s ease;
    position: relative;
    overflow: hidden;
}

.btn:active {
    transform: scale(0.97);
}

.btn-primary {
    background: var(--white);
    color: var(--green-700);
    box-shadow: var(--shadow-md);
}

.btn-primary:hover {
    background: var(--green-50);
    box-shadow: var(--shadow-lg);
    transform: translateY(-1px);
}

.btn-secondary {
    background: rgba(255,255,255,0.15);
    color: var(--white);
    border: 2px solid rgba(255,255,255,0.3);
    backdrop-filter: blur(10px);
}

.btn-secondary:hover {
    background: rgba(255,255,255,0.25);
    border-color: rgba(255,255,255,0.5);
}

.btn-large {
    padding: 1.125rem 2rem;
    font-size: 1.1rem;
    border-radius: var(--radius-xl);
}

.btn-ghost {
    background: transparent;
    color: var(--gray-500);
}

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

.btn-success {
    background: var(--green-500);
    color: var(--white);
    box-shadow: 0 4px 0 var(--green-700), var(--shadow-md);
}

.btn-success:hover {
    background: var(--green-600);
}

.btn-success:active {
    box-shadow: 0 1px 0 var(--green-700);
    transform: translateY(3px);
}

.btn-danger {
    background: var(--red-500);
    color: var(--white);
}

.btn-answer {
    background: var(--white);
    color: var(--gray-800);
    border: 2px solid var(--gray-200);
    padding: 1rem 1.25rem;
    text-align: left;
    border-radius: var(--radius-md);
    font-size: 1rem;
    font-weight: 600;
    box-shadow: 0 3px 0 var(--gray-200);
    width: 100%;
}

.btn-answer:hover {
    border-color: var(--green-400);
    background: var(--green-50);
}

.btn-answer:active {
    box-shadow: 0 1px 0 var(--gray-200);
    transform: translateY(2px);
}

.btn-answer.selected {
    border-color: var(--green-500);
    background: var(--green-50);
    color: var(--green-700);
    box-shadow: 0 3px 0 var(--green-300);
}

.btn-answer.correct {
    border-color: var(--green-500);
    background: var(--green-100);
    color: var(--green-800);
    animation: popIn 0.3s ease;
}

.btn-answer.incorrect {
    border-color: var(--red-400);
    background: #fef2f2;
    color: var(--red-500);
    animation: shake 0.4s ease;
}

.btn-answer.disabled {
    pointer-events: none;
    opacity: 0.7;
}

.btn-icon {
    font-size: 1.25rem;
}

.btn-back {
    width: 40px;
    height: 40px;
    border-radius: var(--radius-full);
    border: none;
    background: var(--gray-100);
    font-size: 1.25rem;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all 0.2s ease;
    font-family: var(--font-family);
    font-weight: 700;
    color: var(--gray-600);
}

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

.btn-icon-action {
    width: 40px;
    height: 40px;
    border-radius: var(--radius-full);
    border: 2px solid var(--green-500);
    background: var(--green-50);
    color: var(--green-600);
    font-size: 1.5rem;
    font-weight: 700;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all 0.2s ease;
    font-family: var(--font-family);
}

.btn-icon-action:hover {
    background: var(--green-500);
    color: var(--white);
}

/* ============================================
   Screen Header
   ============================================ */
.screen-header {
    display: flex;
    align-items: center;
    gap: 1rem;
    padding: 1rem 1.5rem;
    background: var(--white);
    border-bottom: 1px solid var(--gray-100);
    position: sticky;
    top: 0;
    z-index: 10;
}

.screen-header h2 {
    flex: 1;
    font-size: 1.25rem;
    font-weight: 800;
    color: var(--gray-800);
}

.header-points {
    display: flex;
    align-items: center;
}

.points-badge {
    background: linear-gradient(135deg, var(--green-500), var(--green-600));
    color: var(--white);
    padding: 0.375rem 0.875rem;
    border-radius: var(--radius-full);
    font-size: 0.875rem;
    font-weight: 800;
    box-shadow: var(--shadow-sm);
}

/* ============================================
   Sessions List
   ============================================ */
.sessions-list {
    padding: 1.5rem;
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.session-card {
    background: var(--white);
    border-radius: var(--radius-lg);
    padding: 1.25rem;
    box-shadow: var(--shadow-md);
    display: flex;
    align-items: center;
    gap: 1rem;
    cursor: pointer;
    transition: all 0.2s ease;
    border: 2px solid transparent;
}

.session-card:hover {
    border-color: var(--green-200);
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
}

.session-icon {
    width: 56px;
    height: 56px;
    border-radius: var(--radius-md);
    background: var(--green-50);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.75rem;
    flex-shrink: 0;
}

.session-info {
    flex: 1;
    min-width: 0;
}

.session-name {
    font-size: 1rem;
    font-weight: 700;
    color: var(--gray-800);
    margin-bottom: 0.25rem;
}

.session-meta {
    display: flex;
    gap: 1rem;
    font-size: 0.8rem;
    color: var(--gray-500);
}

.session-progress {
    width: 60px;
    text-align: right;
}

.session-progress-ring {
    width: 48px;
    height: 48px;
}

.session-delete {
    width: 32px;
    height: 32px;
    border: none;
    background: none;
    color: var(--gray-400);
    cursor: pointer;
    border-radius: var(--radius-sm);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1rem;
    transition: all 0.2s;
}

.session-delete:hover {
    color: var(--red-500);
    background: #fef2f2;
}

.empty-sessions {
    text-align: center;
    padding: 4rem 2rem;
    color: var(--gray-400);
}

.empty-sessions-icon {
    font-size: 3rem;
    margin-bottom: 1rem;
}

.empty-sessions h3 {
    color: var(--gray-600);
    margin-bottom: 0.5rem;
}

/* ============================================
   Modal
   ============================================ */
.modal {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0,0,0,0.5);
    z-index: 100;
    align-items: center;
    justify-content: center;
    padding: 1rem;
    backdrop-filter: blur(4px);
}

.modal.active {
    display: flex;
}

.modal-content {
    background: var(--white);
    border-radius: var(--radius-xl);
    padding: 2rem;
    width: 100%;
    max-width: 400px;
    animation: popIn 0.3s ease;
}

.modal-content h3 {
    font-size: 1.25rem;
    font-weight: 800;
    margin-bottom: 1.5rem;
    color: var(--gray-800);
}

.form-group {
    margin-bottom: 1.25rem;
}

.form-group label {
    display: block;
    font-size: 0.875rem;
    font-weight: 700;
    color: var(--gray-600);
    margin-bottom: 0.5rem;
}

.form-group input {
    width: 100%;
    padding: 0.875rem 1rem;
    border: 2px solid var(--gray-200);
    border-radius: var(--radius-md);
    font-family: var(--font-family);
    font-size: 1rem;
    font-weight: 600;
    transition: border-color 0.2s;
    outline: none;
}

.form-group input:focus {
    border-color: var(--green-500);
}

.icon-picker {
    display: flex;
    gap: 0.5rem;
    flex-wrap: wrap;
}

.icon-option {
    width: 44px;
    height: 44px;
    border: 2px solid var(--gray-200);
    border-radius: var(--radius-md);
    background: var(--white);
    font-size: 1.25rem;
    cursor: pointer;
    transition: all 0.2s;
    display: flex;
    align-items: center;
    justify-content: center;
}

.icon-option:hover {
    border-color: var(--green-300);
}

.icon-option.selected {
    border-color: var(--green-500);
    background: var(--green-50);
}

.modal-actions {
    display: flex;
    gap: 0.75rem;
    justify-content: flex-end;
    margin-top: 1.5rem;
}

/* ============================================
   Dashboard
   ============================================ */
.dashboard-content {
    padding: 1.5rem;
    max-width: 600px;
    margin: 0 auto;
    width: 100%;
}

.progress-overview {
    background: linear-gradient(135deg, var(--green-500), var(--green-600));
    border-radius: var(--radius-xl);
    padding: 1.5rem;
    color: var(--white);
    margin-bottom: 2rem;
    box-shadow: var(--shadow-lg);
    position: relative;
    overflow: hidden;
}

.progress-overview::after {
    content: '';
    position: absolute;
    top: -20px;
    right: -20px;
    width: 120px;
    height: 120px;
    background: rgba(255,255,255,0.1);
    border-radius: 50%;
}

.progress-title {
    font-size: 0.875rem;
    opacity: 0.9;
    margin-bottom: 0.5rem;
}

.progress-stats {
    display: flex;
    gap: 1.5rem;
    margin-bottom: 1rem;
}

.progress-stat-value {
    font-size: 1.75rem;
    font-weight: 900;
}

.progress-stat-label {
    font-size: 0.75rem;
    opacity: 0.8;
}

.progress-bar {
    height: 8px;
    background: rgba(255,255,255,0.3);
    border-radius: var(--radius-full);
    overflow: hidden;
}

.progress-bar-fill {
    height: 100%;
    background: var(--white);
    border-radius: var(--radius-full);
    transition: width 0.5s ease;
}

.levels-grid {
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.level-card {
    background: var(--white);
    border-radius: var(--radius-lg);
    padding: 1.25rem;
    box-shadow: var(--shadow-md);
    display: flex;
    align-items: center;
    gap: 1rem;
    cursor: pointer;
    transition: all 0.2s ease;
    border: 2px solid transparent;
    position: relative;
    overflow: hidden;
}

.level-card:hover:not(.locked) {
    border-color: var(--green-200);
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
}

.level-card.locked {
    opacity: 0.6;
    cursor: not-allowed;
}

.level-card.locked::after {
    content: '🔒';
    position: absolute;
    right: 1rem;
    font-size: 1.25rem;
}

.level-card.completed {
    border-color: var(--green-200);
    background: var(--green-50);
}

.level-number {
    width: 48px;
    height: 48px;
    border-radius: var(--radius-full);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.25rem;
    font-weight: 900;
    flex-shrink: 0;
}

.level-card:not(.locked):not(.completed) .level-number {
    background: var(--green-100);
    color: var(--green-700);
}

.level-card.completed .level-number {
    background: var(--green-500);
    color: var(--white);
}

.level-card.locked .level-number {
    background: var(--gray-200);
    color: var(--gray-400);
}

.level-info {
    flex: 1;
}

.level-title {
    font-size: 1rem;
    font-weight: 700;
    color: var(--gray-800);
    margin-bottom: 0.25rem;
}

.level-description {
    font-size: 0.8rem;
    color: var(--gray-500);
}

.level-stars {
    display: flex;
    gap: 2px;
    margin-top: 0.25rem;
}

.star {
    font-size: 0.875rem;
    color: var(--gray-300);
}

.star.earned {
    color: var(--yellow-400);
}

/* ============================================
   Lesson Screen
   ============================================ */
.lesson-header {
    display: flex;
    align-items: center;
    gap: 1rem;
    padding: 1rem 1.5rem;
    background: var(--white);
    border-bottom: 1px solid var(--gray-100);
    position: sticky;
    top: 0;
    z-index: 10;
}

.lesson-progress-bar {
    flex: 1;
    height: 12px;
    background: var(--gray-200);
    border-radius: var(--radius-full);
    overflow: hidden;
}

.lesson-progress-fill {
    height: 100%;
    background: linear-gradient(90deg, var(--green-400), var(--green-500));
    border-radius: var(--radius-full);
    transition: width 0.4s ease;
    min-width: 0;
}

.lesson-hearts {
    display: flex;
    gap: 4px;
    font-size: 1.25rem;
}

.heart {
    transition: all 0.3s;
}

.heart.lost {
    opacity: 0.2;
    transform: scale(0.8);
}

.lesson-content {
    flex: 1;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    padding: 2rem;
    max-width: 600px;
    margin: 0 auto;
    width: 100%;
}

/* Exercise Types */
.exercise-container {
    width: 100%;
    animation: slideUp 0.4s ease;
}

.exercise-type-label {
    font-size: 0.75rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 1px;
    color: var(--gray-400);
    margin-bottom: 0.75rem;
}

.exercise-question {
    font-size: 1.5rem;
    font-weight: 800;
    color: var(--gray-800);
    margin-bottom: 0.5rem;
    line-height: 1.4;
}

.exercise-hint {
    font-size: 1rem;
    color: var(--gray-500);
    margin-bottom: 2rem;
    font-style: italic;
}

.exercise-word-display {
    background: var(--white);
    border: 2px solid var(--gray-200);
    border-radius: var(--radius-lg);
    padding: 1.5rem 2rem;
    text-align: center;
    margin-bottom: 2rem;
    box-shadow: var(--shadow-sm);
}

.exercise-word {
    font-size: 2rem;
    font-weight: 900;
    color: var(--green-700);
    margin-bottom: 0.25rem;
}

.exercise-word-sub {
    font-size: 0.9rem;
    color: var(--gray-500);
}

.answers-grid {
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
    width: 100%;
    margin-bottom: 1.5rem;
}

.answer-pair {
    display: flex;
    gap: 0.5rem;
}

.text-input-container {
    width: 100%;
    margin-bottom: 1.5rem;
}

.text-input {
    width: 100%;
    padding: 1rem 1.25rem;
    border: 2px solid var(--gray-200);
    border-radius: var(--radius-md);
    font-family: var(--font-family);
    font-size: 1.125rem;
    font-weight: 600;
    outline: none;
    transition: border-color 0.2s;
    text-align: center;
}

.text-input:focus {
    border-color: var(--green-500);
}

.text-input.correct {
    border-color: var(--green-500);
    background: var(--green-50);
}

.text-input.incorrect {
    border-color: var(--red-400);
    background: #fef2f2;
}

.check-btn-container {
    width: 100%;
}

.feedback-banner {
    width: 100%;
    padding: 1.25rem;
    border-radius: var(--radius-lg);
    margin-bottom: 1rem;
    animation: slideUp 0.3s ease;
    display: flex;
    align-items: center;
    gap: 0.75rem;
}

.feedback-banner.correct {
    background: var(--green-100);
    color: var(--green-800);
    border: 2px solid var(--green-300);
}

.feedback-banner.incorrect {
    background: #fef2f2;
    color: var(--red-500);
    border: 2px solid #fecaca;
}

.feedback-icon {
    font-size: 1.5rem;
}

.feedback-text {
    flex: 1;
}

.feedback-text strong {
    display: block;
    font-size: 1rem;
    margin-bottom: 0.125rem;
}

.feedback-text span {
    font-size: 0.875rem;
    opacity: 0.8;
}

/* Word Bank Exercise */
.word-bank-dropzone {
    min-height: 56px;
    border: 2px dashed var(--gray-300);
    border-radius: var(--radius-md);
    padding: 0.75rem;
    margin-bottom: 1.5rem;
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
    align-items: center;
    justify-content: center;
    transition: all 0.2s;
}

.word-bank-dropzone.has-words {
    border-style: solid;
    border-color: var(--green-300);
    background: var(--green-50);
}

.word-bank {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
    justify-content: center;
    margin-bottom: 1.5rem;
}

.word-chip {
    padding: 0.625rem 1rem;
    background: var(--white);
    border: 2px solid var(--gray-200);
    border-radius: var(--radius-md);
    font-family: var(--font-family);
    font-size: 0.95rem;
    font-weight: 700;
    cursor: pointer;
    transition: all 0.2s;
    box-shadow: 0 2px 0 var(--gray-200);
    user-select: none;
}

.word-chip:hover {
    border-color: var(--green-400);
    background: var(--green-50);
}

.word-chip:active {
    transform: translateY(2px);
    box-shadow: none;
}

.word-chip.used {
    opacity: 0.3;
    pointer-events: none;
}

.word-chip.in-zone {
    background: var(--green-100);
    border-color: var(--green-400);
    color: var(--green-800);
}

/* Matching Exercise */
.matching-container {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 0.75rem;
    width: 100%;
    margin-bottom: 1.5rem;
}

.match-item {
    padding: 0.875rem;
    background: var(--white);
    border: 2px solid var(--gray-200);
    border-radius: var(--radius-md);
    font-weight: 700;
    text-align: center;
    cursor: pointer;
    transition: all 0.2s;
    font-family: var(--font-family);
    font-size: 0.95rem;
}

.match-item:hover:not(.matched) {
    border-color: var(--green-400);
}

.match-item.selected {
    border-color: var(--blue-500);
    background: #eff6ff;
    color: var(--blue-500);
}

.match-item.matched {
    border-color: var(--green-400);
    background: var(--green-100);
    color: var(--green-700);
    pointer-events: none;
    opacity: 0.7;
}

.match-item.wrong {
    border-color: var(--red-400);
    background: #fef2f2;
    animation: shake 0.3s ease;
}

/* ============================================
   Results Screen
   ============================================ */
.results-container {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    min-height: 100vh;
    padding: 2rem;
    text-align: center;
}

.results-icon {
    font-size: 5rem;
    margin-bottom: 1rem;
    animation: bounceIn 0.6s ease;
}

.results-title {
    font-size: 2rem;
    font-weight: 900;
    color: var(--gray-800);
    margin-bottom: 0.5rem;
}

.results-subtitle {
    font-size: 1rem;
    color: var(--gray-500);
    margin-bottom: 2rem;
}

.results-stats {
    display: flex;
    gap: 2rem;
    margin-bottom: 2rem;
}

.result-stat {
    text-align: center;
}

.result-stat-value {
    font-size: 2rem;
    font-weight: 900;
}

.result-stat-value.points {
    color: var(--green-600);
}

.result-stat-value.accuracy {
    color: var(--blue-500);
}

.result-stat-label {
    font-size: 0.8rem;
    color: var(--gray-500);
    font-weight: 600;
}

.results-stars {
    display: flex;
    gap: 0.5rem;
    margin-bottom: 2rem;
}

.results-stars .star {
    font-size: 2.5rem;
    animation: bounceIn 0.5s ease;
}

.results-stars .star:nth-child(2) {
    animation-delay: 0.15s;
}

.results-stars .star:nth-child(3) {
    animation-delay: 0.3s;
}

.results-actions {
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
    width: 100%;
    max-width: 300px;
}

/* ============================================
   Toast Notifications
   ============================================ */
#toast-container {
    position: fixed;
    bottom: 2rem;
    left: 50%;
    transform: translateX(-50%);
    z-index: 200;
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
    pointer-events: none;
}

.toast {
    background: var(--gray-800);
    color: var(--white);
    padding: 0.875rem 1.5rem;
    border-radius: var(--radius-lg);
    font-weight: 700;
    font-size: 0.9rem;
    box-shadow: var(--shadow-xl);
    animation: slideUp 0.3s ease, fadeOut 0.3s ease 2.5s forwards;
    white-space: nowrap;
}

.toast.success {
    background: var(--green-600);
}

.toast.error {
    background: var(--red-500);
}

@keyframes fadeOut {
    to { opacity: 0; transform: translateY(10px); }
}

/* ============================================
   Responsive
   ============================================ */
@media (max-width: 480px) {
    .app-title {
        font-size: 2.25rem;
    }

    .exercise-question {
        font-size: 1.25rem;
    }

    .exercise-word {
        font-size: 1.5rem;
    }

    .lesson-content {
        padding: 1.5rem;
    }

    .results-stats {
        gap: 1.5rem;
    }

    .matching-container {
        gap: 0.5rem;
    }

    .match-item {
        padding: 0.75rem 0.5rem;
        font-size: 0.85rem;
    }
}

@media (min-width: 768px) {
    .dashboard-content {
        padding: 2rem;
    }

    .sessions-list {
        max-width: 600px;
        margin: 0 auto;
    }
}

/* ============================================
   Confetti Effect
   ============================================ */
.confetti-container {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    pointer-events: none;
    z-index: 300;
    overflow: hidden;
}

.confetti-piece {
    position: absolute;
    width: 10px;
    height: 10px;
    border-radius: 2px;
    animation: confettiFall 3s ease-in forwards;
}

@keyframes confettiFall {
    0% {
        transform: translateY(-20px) rotate(0deg);
        opacity: 1;
    }
    100% {
        transform: translateY(100vh) rotate(720deg);
        opacity: 0;
    }
}

/* ============================================
   Streak indicator
   ============================================ */
.streak-indicator {
    position: fixed;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    font-size: 3rem;
    font-weight: 900;
    color: var(--orange-500);
    text-shadow: 0 2px 10px rgba(249, 115, 22, 0.3);
    animation: popIn 0.4s ease, fadeOut 0.3s ease 0.8s forwards;
    z-index: 150;
    pointer-events: none;
}

/* ============================================
   Listening exercise (speaker icon)
   ============================================ */
.speaker-btn {
    width: 80px;
    height: 80px;
    border-radius: var(--radius-full);
    border: 3px solid var(--green-400);
    background: var(--green-50);
    color: var(--green-600);
    font-size: 2rem;
    cursor: pointer;
    margin-bottom: 1.5rem;
    transition: all 0.2s;
    display: flex;
    align-items: center;
    justify-content: center;
}

.speaker-btn:hover {
    background: var(--green-100);
    transform: scale(1.05);
}

.speaker-btn:active {
    transform: scale(0.95);
}