/* ============================================
   MATE KIDS - Design System & Styles
   Candy-themed gamified math app for kids
   ============================================ */

/* --- CSS Custom Properties --- */
:root {
    /* Primary palette - Candy/Sweet theme */
    --primary: #6C3CE1;
    --primary-light: #8B5CF6;
    --primary-dark: #5521C6;
    --primary-glow: rgba(108, 60, 225, 0.3);
    
    /* Accent colors */
    --accent-pink: #F472B6;
    --accent-yellow: #FBBF24;
    --accent-green: #34D399;
    --accent-blue: #60A5FA;
    --accent-orange: #FB923C;
    --accent-red: #F87171;
    
    /* World theme colors */
    --world1-primary: #34D399;
    --world1-secondary: #6EE7B7;
    --world1-bg: linear-gradient(135deg, #064E3B, #065F46, #047857);
    
    --world2-primary: #60A5FA;
    --world2-secondary: #93C5FD;
    --world2-bg: linear-gradient(135deg, #1E3A5F, #1E40AF, #3B82F6);
    
    --world3-primary: #FBBF24;
    --world3-secondary: #FCD34D;
    --world3-bg: linear-gradient(135deg, #78350F, #92400E, #B45309);
    
    --world4-primary: #F472B6;
    --world4-secondary: #F9A8D4;
    --world4-bg: linear-gradient(135deg, #831843, #9D174D, #BE185D);
    
    --world5-primary: #FB923C;
    --world5-secondary: #FDBA74;
    --world5-bg: linear-gradient(135deg, #7C2D12, #9A3412, #C2410C);
    
    /* Neutrals */
    --bg-dark: #1B0A3C;
    --bg-card: rgba(255, 255, 255, 0.1);
    --bg-card-hover: rgba(255, 255, 255, 0.16);
    --bg-glass: rgba(255, 255, 255, 0.12);
    --border-glass: rgba(255, 255, 255, 0.18);
    --text-primary: #F8FAFC;
    --text-secondary: rgba(248, 250, 252, 0.8);
    --text-muted: rgba(248, 250, 252, 0.5);
    
    /* Shadows */
    --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.2);
    --shadow-md: 0 4px 16px rgba(0, 0, 0, 0.3);
    --shadow-lg: 0 8px 32px rgba(0, 0, 0, 0.4);
    --shadow-glow: 0 0 30px var(--primary-glow);
    
    /* Borders */
    --radius-sm: 8px;
    --radius-md: 12px;
    --radius-lg: 20px;
    --radius-xl: 28px;
    --radius-full: 9999px;
    
    /* Spacing */
    --space-xs: 4px;
    --space-sm: 8px;
    --space-md: 16px;
    --space-lg: 24px;
    --space-xl: 32px;
    --space-2xl: 48px;
    
    /* Typography */
    --font-display: 'Fredoka', 'Segoe UI', sans-serif;
    --font-body: 'Outfit', 'Segoe UI', sans-serif;
    
    /* Transitions */
    --transition-fast: 0.15s ease;
    --transition-normal: 0.3s ease;
    --transition-slow: 0.5s ease;
    --transition-bounce: 0.4s cubic-bezier(0.68, -0.55, 0.265, 1.55);
}

/* --- Reset & Base --- */
*, *::before, *::after {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    font-size: 16px;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

body {
    font-family: var(--font-body);
    background: linear-gradient(135deg, #1B0A3C 0%, #2D1B69 25%, #1a1145 50%, #0f2847 75%, #1B0A3C 100%);
    background-attachment: fixed;
    color: var(--text-primary);
    min-height: 100vh;
    overflow-x: hidden;
    line-height: 1.5;
}

/* Estrellas decorativas de fondo */
body::before {
    content: '';
    position: fixed;
    inset: 0;
    background-image:
        radial-gradient(2px 2px at 10% 15%, rgba(255,255,255,0.4), transparent),
        radial-gradient(2px 2px at 25% 35%, rgba(255,255,255,0.3), transparent),
        radial-gradient(1px 1px at 40% 10%, rgba(255,255,255,0.5), transparent),
        radial-gradient(2px 2px at 55% 45%, rgba(255,255,255,0.25), transparent),
        radial-gradient(1px 1px at 70% 20%, rgba(255,255,255,0.4), transparent),
        radial-gradient(2px 2px at 85% 55%, rgba(255,255,255,0.3), transparent),
        radial-gradient(1px 1px at 15% 65%, rgba(255,255,255,0.35), transparent),
        radial-gradient(2px 2px at 30% 80%, rgba(255,255,255,0.2), transparent),
        radial-gradient(1px 1px at 60% 75%, rgba(255,255,255,0.45), transparent),
        radial-gradient(2px 2px at 90% 85%, rgba(255,255,255,0.3), transparent),
        radial-gradient(1px 1px at 45% 90%, rgba(255,255,255,0.25), transparent),
        radial-gradient(2px 2px at 75% 60%, rgba(255,255,255,0.35), transparent),
        radial-gradient(1px 1px at 5% 50%, rgba(255,255,255,0.4), transparent),
        radial-gradient(2px 2px at 95% 30%, rgba(255,255,255,0.3), transparent),
        radial-gradient(1px 1px at 50% 55%, rgba(255,255,255,0.2), transparent);
    pointer-events: none;
    z-index: 0;
    animation: twinkle 4s ease-in-out infinite alternate;
}

@keyframes twinkle {
    0% { opacity: 0.6; }
    100% { opacity: 1; }
}

#app {
    position: relative;
    min-height: 100vh;
    width: 100%;
    overflow: hidden;
}

/* --- Screen Management --- */
.screen {
    display: none;
    min-height: 100vh;
    width: 100%;
    position: relative;
    animation: fadeIn 0.4s 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(40px); }
    to { opacity: 1; transform: translateY(0); }
}

@keyframes slideDown {
    from { opacity: 0; transform: translateY(-40px); }
    to { opacity: 1; transform: translateY(0); }
}

@keyframes scaleIn {
    from { opacity: 0; transform: scale(0.8); }
    to { opacity: 1; transform: scale(1); }
}

@keyframes popIn {
    0% { transform: scale(0); opacity: 0; }
    60% { transform: scale(1.15); }
    100% { transform: scale(1); opacity: 1; }
}

@keyframes bounceIn {
    0% { transform: scale(0.3); opacity: 0; }
    50% { transform: scale(1.05); }
    70% { transform: scale(0.95); }
    100% { transform: scale(1); opacity: 1; }
}

@keyframes shake {
    0%, 100% { transform: translateX(0); }
    25% { transform: translateX(-8px); }
    75% { transform: translateX(8px); }
}

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

@keyframes float {
    0%, 100% { transform: translateY(0px); }
    50% { transform: translateY(-10px); }
}

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

@keyframes starPop {
    0% { transform: scale(0) rotate(-45deg); opacity: 0; }
    60% { transform: scale(1.3) rotate(10deg); opacity: 1; }
    100% { transform: scale(1) rotate(0deg); opacity: 1; }
}

@keyframes confettiDrop {
    0% { transform: translateY(-50px) rotate(0deg); opacity: 1; }
    100% { transform: translateY(100vh) rotate(360deg); opacity: 0; }
}

@keyframes shimmer {
    0% { background-position: -200% center; }
    100% { background-position: 200% center; }
}

@keyframes heartbeat {
    0%, 100% { transform: scale(1); }
    15% { transform: scale(1.3); }
    30% { transform: scale(1); }
    45% { transform: scale(1.15); }
}

/* --- Loading Screen --- */
.loading-container {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    min-height: 100vh;
    padding: var(--space-xl);
    background: radial-gradient(ellipse at center, #3b1f7a 0%, #2D1B69 40%, transparent 80%);
    position: relative;
    z-index: 1;
}

.loading-logo {
    text-align: center;
    animation: bounceIn 0.8s ease;
}

.logo-emoji {
    font-size: 80px;
    display: block;
    margin-bottom: var(--space-md);
    animation: float 3s ease-in-out infinite;
    filter: drop-shadow(0 4px 20px rgba(108, 60, 225, 0.4));
}

.logo-text {
    font-family: var(--font-display);
    font-size: 3rem;
    font-weight: 700;
    background: linear-gradient(135deg, var(--accent-yellow), var(--accent-pink), var(--primary-light));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    text-shadow: none;
    margin-bottom: var(--space-xs);
}

.logo-subtitle {
    font-family: var(--font-body);
    font-size: 1.1rem;
    color: var(--text-secondary);
    font-weight: 400;
}

.loading-bar-container {
    width: 200px;
    height: 6px;
    background: var(--bg-glass);
    border-radius: var(--radius-full);
    margin-top: var(--space-2xl);
    overflow: hidden;
}

.loading-bar {
    width: 0%;
    height: 100%;
    background: linear-gradient(90deg, var(--primary), var(--accent-pink));
    border-radius: var(--radius-full);
    transition: width 0.3s ease;
    animation: shimmer 1.5s infinite;
    background-size: 200% 100%;
}

.loading-tip {
    margin-top: var(--space-md);
    font-size: 0.85rem;
    color: var(--text-muted);
}

/* --- Login Screen --- */
.login-screen {
    justify-content: center;
    align-items: center;
    padding: var(--space-xl);
    background: radial-gradient(ellipse at top center, #4a2090 0%, #2D1B69 40%, transparent 80%);
    position: relative;
    z-index: 1;
}

.login-card {
    width: 100%;
    max-width: 420px;
    background: var(--bg-glass);
    backdrop-filter: blur(20px);
    border: 1px solid var(--border-glass);
    border-radius: var(--radius-xl);
    padding: var(--space-2xl) var(--space-xl);
    text-align: center;
    animation: scaleIn 0.5s ease;
    box-shadow: var(--shadow-lg), var(--shadow-glow);
}

.login-card .logo-emoji {
    font-size: 64px;
}

.login-card .logo-text {
    font-size: 2.2rem;
    margin-bottom: var(--space-sm);
}

.login-card .logo-subtitle {
    margin-bottom: var(--space-xl);
}

.avatar-selector {
    display: flex;
    gap: var(--space-sm);
    justify-content: center;
    flex-wrap: wrap;
    margin-bottom: var(--space-lg);
}

.avatar-option {
    width: 52px;
    height: 52px;
    font-size: 28px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: var(--radius-lg);
    border: 2px solid transparent;
    background: var(--bg-card);
    cursor: pointer;
    transition: all var(--transition-bounce);
}

.avatar-option:hover {
    transform: scale(1.1);
    background: var(--bg-card-hover);
}

.avatar-option.selected {
    border-color: var(--primary-light);
    background: rgba(108, 60, 225, 0.2);
    transform: scale(1.1);
    box-shadow: 0 0 15px var(--primary-glow);
}

.input-group {
    margin-bottom: var(--space-lg);
}

.input-group label {
    display: block;
    text-align: left;
    font-size: 0.85rem;
    font-weight: 500;
    color: var(--text-secondary);
    margin-bottom: var(--space-sm);
}

.input-field {
    width: 100%;
    padding: 14px 18px;
    background: rgba(255, 255, 255, 0.05);
    border: 1px solid var(--border-glass);
    border-radius: var(--radius-md);
    color: var(--text-primary);
    font-family: var(--font-body);
    font-size: 1rem;
    transition: all var(--transition-normal);
    outline: none;
}

.input-field::placeholder {
    color: var(--text-muted);
}

.input-field:focus {
    border-color: var(--primary-light);
    background: rgba(108, 60, 225, 0.08);
    box-shadow: 0 0 0 3px var(--primary-glow);
}

/* --- Buttons --- */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: var(--space-sm);
    padding: 14px 28px;
    border: none;
    border-radius: var(--radius-lg);
    font-family: var(--font-display);
    font-size: 1.1rem;
    font-weight: 600;
    cursor: pointer;
    transition: all var(--transition-bounce);
    position: relative;
    overflow: hidden;
    user-select: none;
    -webkit-tap-highlight-color: transparent;
}

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

.btn-primary {
    background: linear-gradient(135deg, var(--primary), var(--primary-light));
    color: white;
    box-shadow: 0 4px 15px var(--primary-glow);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 25px var(--primary-glow);
}

.btn-success {
    background: linear-gradient(135deg, #059669, var(--accent-green));
    color: white;
    box-shadow: 0 4px 15px rgba(52, 211, 153, 0.3);
}

.btn-success:hover {
    transform: translateY(-2px);
}

.btn-danger {
    background: linear-gradient(135deg, #DC2626, var(--accent-red));
    color: white;
    box-shadow: 0 4px 15px rgba(248, 113, 113, 0.3);
}

.btn-outline {
    background: transparent;
    color: var(--text-primary);
    border: 2px solid var(--border-glass);
}

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

.btn-full {
    width: 100%;
}

.btn-sm {
    padding: 8px 16px;
    font-size: 0.9rem;
    border-radius: var(--radius-md);
}

.btn-lg {
    padding: 18px 36px;
    font-size: 1.3rem;
}

.btn:disabled {
    opacity: 0.5;
    cursor: not-allowed;
    transform: none !important;
}

/* --- Map Screen --- */
.map-screen {
    background: radial-gradient(ellipse at 20% 0%, rgba(108,60,225,0.2) 0%, transparent 50%),
                radial-gradient(ellipse at 80% 100%, rgba(244,114,182,0.15) 0%, transparent 50%);
    position: relative;
    z-index: 1;
}

.map-header {
    position: sticky;
    top: 0;
    z-index: 100;
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: var(--space-md) var(--space-lg);
    background: rgba(27, 10, 60, 0.85);
    backdrop-filter: blur(20px);
    border-bottom: 1px solid var(--border-glass);
}

.map-header-left {
    display: flex;
    align-items: center;
    gap: var(--space-md);
}

.map-user-avatar {
    width: 40px;
    height: 40px;
    font-size: 24px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--bg-glass);
    border-radius: var(--radius-md);
    border: 1px solid var(--border-glass);
}

.map-user-info {
    display: flex;
    flex-direction: column;
}

.map-user-name {
    font-family: var(--font-display);
    font-weight: 600;
    font-size: 0.95rem;
}

.map-user-stars {
    font-size: 0.8rem;
    color: var(--accent-yellow);
    display: flex;
    align-items: center;
    gap: 4px;
}

.map-header-right {
    display: flex;
    gap: var(--space-sm);
}

.header-btn {
    width: 40px;
    height: 40px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--bg-glass);
    border: 1px solid var(--border-glass);
    border-radius: var(--radius-md);
    font-size: 1.2rem;
    cursor: pointer;
    transition: all var(--transition-normal);
    color: var(--text-primary);
}

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

/* World sections */
.map-content {
    padding: var(--space-md) var(--space-lg);
    padding-bottom: 100px;
}

.world-section {
    margin-bottom: var(--space-2xl);
    animation: slideUp 0.5s ease;
}

.world-header {
    display: flex;
    align-items: center;
    gap: var(--space-md);
    padding: var(--space-lg);
    border-radius: var(--radius-xl);
    margin-bottom: var(--space-lg);
    position: relative;
    overflow: hidden;
}

.world-header::before {
    content: '';
    position: absolute;
    inset: 0;
    opacity: 0.15;
    background: radial-gradient(circle at 80% 50%, white, transparent 60%);
}

.world-emoji {
    font-size: 40px;
    z-index: 1;
    animation: float 4s ease-in-out infinite;
}

.world-info {
    flex: 1;
    z-index: 1;
}

.world-name {
    font-family: var(--font-display);
    font-weight: 700;
    font-size: 1.2rem;
    margin-bottom: 2px;
}

.world-desc {
    font-size: 0.8rem;
    color: rgba(255, 255, 255, 0.7);
}

.world-progress {
    z-index: 1;
    text-align: right;
}

.world-stars-count {
    font-family: var(--font-display);
    font-weight: 600;
    font-size: 0.9rem;
    color: var(--accent-yellow);
}

.world-progress-bar {
    width: 60px;
    height: 4px;
    background: rgba(255, 255, 255, 0.2);
    border-radius: var(--radius-full);
    margin-top: 4px;
    overflow: hidden;
}

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

/* Level nodes */
.level-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(60px, 1fr));
    gap: var(--space-sm);
    max-width: 700px;
}

.level-node {
    position: relative;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    aspect-ratio: 1;
    border-radius: var(--radius-lg);
    cursor: pointer;
    transition: all var(--transition-bounce);
    border: 2px solid transparent;
    background: var(--bg-card);
}

.level-node:hover:not(.locked) {
    transform: scale(1.08);
}

.level-node:active:not(.locked) {
    transform: scale(0.95);
}

.level-node.current {
    border-color: var(--primary-light);
    box-shadow: 0 0 20px var(--primary-glow);
    animation: pulse 2s ease-in-out infinite;
}

.level-node.completed {
    border-color: rgba(52, 211, 153, 0.3);
    background: rgba(52, 211, 153, 0.08);
}

.level-node.locked {
    opacity: 0.35;
    cursor: not-allowed;
}

.level-number {
    font-family: var(--font-display);
    font-weight: 700;
    font-size: 1.2rem;
    line-height: 1;
}

.level-stars {
    display: flex;
    gap: 1px;
    margin-top: 4px;
}

.level-stars .star {
    font-size: 10px;
    opacity: 0.3;
}

.level-stars .star.earned {
    opacity: 1;
}

.level-node.locked .level-number {
    display: none;
}

.level-node.locked::after {
    content: '🔒';
    font-size: 1.2rem;
}

/* --- Game Screen --- */
.game-screen {
    background: radial-gradient(ellipse at center, rgba(45,27,105,0.6) 0%, transparent 70%);
    position: relative;
    z-index: 1;
}

.game-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: var(--space-md) var(--space-lg);
    background: rgba(27, 10, 60, 0.9);
    backdrop-filter: blur(20px);
    border-bottom: 1px solid var(--border-glass);
}

.game-back-btn {
    width: 36px;
    height: 36px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--bg-glass);
    border: 1px solid var(--border-glass);
    border-radius: var(--radius-md);
    font-size: 1.1rem;
    cursor: pointer;
    transition: all var(--transition-normal);
    color: var(--text-primary);
}

.game-back-btn:hover {
    background: var(--bg-card-hover);
}

.game-level-info {
    text-align: center;
}

.game-level-title {
    font-family: var(--font-display);
    font-weight: 700;
    font-size: 0.95rem;
}

.game-level-world {
    font-size: 0.75rem;
    color: var(--text-secondary);
}

.game-lives {
    display: flex;
    gap: 4px;
    font-size: 1.3rem;
}

.game-lives .heart {
    transition: all var(--transition-bounce);
}

.game-lives .heart.lost {
    filter: grayscale(1) opacity(0.3);
    transform: scale(0.8);
}

.game-lives .heart.losing {
    animation: shake 0.3s ease;
}

/* Progress bar */
.game-progress {
    padding: var(--space-sm) var(--space-lg);
    display: flex;
    align-items: center;
    gap: var(--space-md);
}

.game-progress-bar {
    flex: 1;
    height: 6px;
    background: var(--bg-glass);
    border-radius: var(--radius-full);
    overflow: hidden;
}

.game-progress-fill {
    height: 100%;
    background: linear-gradient(90deg, var(--primary), var(--accent-pink));
    border-radius: var(--radius-full);
    transition: width 0.4s ease;
}

.game-progress-text {
    font-size: 0.75rem;
    color: var(--text-secondary);
    font-weight: 500;
    white-space: nowrap;
}

.game-timer {
    font-size: 0.75rem;
    color: var(--text-secondary);
    font-weight: 500;
    display: flex;
    align-items: center;
    gap: 4px;
}

/* Exercise area */
.game-content {
    flex: 1;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    padding: var(--space-xl) var(--space-lg);
    gap: var(--space-xl);
}

.exercise-container {
    width: 100%;
    text-align: center;
    animation: scaleIn 0.4s ease;
}

.exercise-emoji-display {
    font-size: 2.5rem;
    margin-bottom: var(--space-md);
    min-height: 60px;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--space-sm);
    flex-wrap: wrap;
}

.exercise-question {
    font-family: var(--font-display);
    font-size: 2.8rem;
    font-weight: 700;
    margin-bottom: var(--space-sm);
    background: linear-gradient(135deg, var(--text-primary), rgba(255,255,255,0.8));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.exercise-instruction {
    font-size: 0.95rem;
    color: var(--text-secondary);
    margin-bottom: var(--space-lg);
}

/* Answer options */
.answer-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--space-md);
    width: 100%;
    max-width: 420px;
    margin: 0 auto;
}

.answer-btn {
    padding: 20px;
    background: var(--bg-glass);
    border: 2px solid var(--border-glass);
    border-radius: var(--radius-xl);
    font-family: var(--font-display);
    font-size: 1.8rem;
    font-weight: 700;
    color: var(--text-primary);
    cursor: pointer;
    transition: all var(--transition-bounce);
    position: relative;
    overflow: hidden;
    user-select: none;
    -webkit-tap-highlight-color: transparent;
}

.answer-btn::before {
    content: '';
    position: absolute;
    inset: 0;
    background: linear-gradient(135deg, transparent 40%, rgba(255,255,255,0.05));
    pointer-events: none;
}

.answer-btn:hover {
    transform: scale(1.05);
    border-color: var(--primary-light);
    background: rgba(108, 60, 225, 0.15);
}

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

.answer-btn.correct {
    border-color: var(--accent-green) !important;
    background: rgba(52, 211, 153, 0.2) !important;
    animation: popIn 0.3s ease;
}

.answer-btn.incorrect {
    border-color: var(--accent-red) !important;
    background: rgba(248, 113, 113, 0.2) !important;
    animation: shake 0.4s ease;
}

.answer-btn.disabled {
    pointer-events: none;
    opacity: 0.5;
}

/* Feedback overlay */
.feedback-overlay {
    position: fixed;
    inset: 0;
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 200;
    pointer-events: none;
}

.feedback-emoji {
    font-size: 80px;
    animation: popIn 0.4s ease;
}

/* --- Results Screen --- */
.results-overlay {
    position: fixed;
    inset: 0;
    background: rgba(0, 0, 0, 0.8);
    backdrop-filter: blur(10px);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 300;
    padding: var(--space-lg);
}

.results-card {
    width: 100%;
    max-width: 440px;
    background: linear-gradient(145deg, #1a1030, #150d25);
    border: 1px solid var(--border-glass);
    border-radius: var(--radius-xl);
    padding: var(--space-2xl) var(--space-xl);
    text-align: center;
    animation: bounceIn 0.6s ease;
    box-shadow: var(--shadow-lg);
}

.results-title {
    font-family: var(--font-display);
    font-size: 1.8rem;
    font-weight: 700;
    margin-bottom: var(--space-lg);
}

.results-stars {
    display: flex;
    justify-content: center;
    gap: var(--space-md);
    margin-bottom: var(--space-xl);
}

.results-star {
    font-size: 48px;
    opacity: 0.2;
    transition: all 0.3s ease;
}

.results-star.earned {
    opacity: 1;
    animation: starPop 0.5s ease forwards;
}

.results-star:nth-child(2).earned {
    animation-delay: 0.2s;
}

.results-star:nth-child(3).earned {
    animation-delay: 0.4s;
}

.results-stats {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--space-md);
    margin-bottom: var(--space-xl);
}

.results-stat {
    background: var(--bg-card);
    border-radius: var(--radius-md);
    padding: var(--space-md);
}

.results-stat-value {
    font-family: var(--font-display);
    font-weight: 700;
    font-size: 1.5rem;
    color: var(--accent-yellow);
}

.results-stat-label {
    font-size: 0.75rem;
    color: var(--text-secondary);
    margin-top: 2px;
}

.results-actions {
    display: flex;
    flex-direction: column;
    gap: var(--space-sm);
}

/* Game over (0 lives) */
.results-card.game-over .results-title {
    color: var(--accent-red);
}

/* --- Stats/Profile Screen --- */
.stats-screen {
    background: var(--bg-dark);
}

.stats-header {
    padding: var(--space-lg);
    text-align: center;
    border-bottom: 1px solid var(--border-glass);
}

.stats-avatar {
    font-size: 56px;
    margin-bottom: var(--space-md);
    animation: float 3s ease-in-out infinite;
}

.stats-username {
    font-family: var(--font-display);
    font-size: 1.5rem;
    font-weight: 700;
    margin-bottom: var(--space-xs);
}

.stats-back-btn {
    position: absolute;
    top: var(--space-md);
    left: var(--space-lg);
    width: 40px;
    height: 40px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--bg-glass);
    border: 1px solid var(--border-glass);
    border-radius: var(--radius-md);
    font-size: 1.1rem;
    cursor: pointer;
    color: var(--text-primary);
    transition: all var(--transition-normal);
}

.stats-content {
    padding: var(--space-lg);
}

.stats-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: var(--space-md);
    margin-bottom: var(--space-xl);
}

.stat-card {
    background: var(--bg-card);
    border: 1px solid var(--border-glass);
    border-radius: var(--radius-lg);
    padding: var(--space-md);
    text-align: center;
}

.stat-card-value {
    font-family: var(--font-display);
    font-weight: 700;
    font-size: 1.5rem;
}

.stat-card-label {
    font-size: 0.7rem;
    color: var(--text-secondary);
    margin-top: 2px;
}

.stats-section-title {
    font-family: var(--font-display);
    font-weight: 600;
    font-size: 1rem;
    margin-bottom: var(--space-md);
    color: var(--text-secondary);
}

/* Leaderboard */
.leaderboard-list {
    display: flex;
    flex-direction: column;
    gap: var(--space-sm);
}

.leaderboard-item {
    display: flex;
    align-items: center;
    gap: var(--space-md);
    background: var(--bg-card);
    border: 1px solid var(--border-glass);
    border-radius: var(--radius-md);
    padding: var(--space-md);
    transition: all var(--transition-normal);
}

.leaderboard-item.self {
    border-color: var(--primary-light);
    background: rgba(108, 60, 225, 0.1);
}

.leaderboard-rank {
    font-family: var(--font-display);
    font-weight: 700;
    font-size: 1rem;
    width: 30px;
    text-align: center;
    color: var(--text-secondary);
}

.leaderboard-rank.gold { color: #FFD700; }
.leaderboard-rank.silver { color: #C0C0C0; }
.leaderboard-rank.bronze { color: #CD7F32; }

.leaderboard-avatar {
    font-size: 1.5rem;
}

.leaderboard-info {
    flex: 1;
}

.leaderboard-name {
    font-weight: 600;
    font-size: 0.9rem;
}

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

.leaderboard-stars {
    font-family: var(--font-display);
    font-weight: 600;
    color: var(--accent-yellow);
    display: flex;
    align-items: center;
    gap: 4px;
}

/* --- Confetti --- */
.confetti-container {
    position: fixed;
    inset: 0;
    pointer-events: none;
    z-index: 400;
    overflow: hidden;
}

.confetti-piece {
    position: absolute;
    top: -20px;
    width: 10px;
    height: 10px;
    border-radius: 2px;
    animation: confettiDrop linear forwards;
}

/* --- Toast Notifications --- */
#toast-container {
    position: fixed;
    top: var(--space-lg);
    left: 50%;
    transform: translateX(-50%);
    z-index: 500;
    display: flex;
    flex-direction: column;
    gap: var(--space-sm);
    width: 90%;
    max-width: 380px;
}

.toast {
    background: rgba(30, 20, 50, 0.95);
    backdrop-filter: blur(20px);
    border: 1px solid var(--border-glass);
    border-radius: var(--radius-md);
    padding: var(--space-md) var(--space-lg);
    display: flex;
    align-items: center;
    gap: var(--space-md);
    animation: slideDown 0.3s ease;
    box-shadow: var(--shadow-lg);
}

.toast-emoji {
    font-size: 1.5rem;
}

.toast-text {
    font-size: 0.9rem;
    font-weight: 500;
}

.toast.success { border-left: 3px solid var(--accent-green); }
.toast.error { border-left: 3px solid var(--accent-red); }
.toast.info { border-left: 3px solid var(--accent-blue); }

/* --- Fraction visual --- */
.fraction-visual {
    display: inline-flex;
    flex-direction: column;
    align-items: center;
    font-family: var(--font-display);
    font-size: 2rem;
    font-weight: 700;
}

.fraction-num {
    border-bottom: 3px solid var(--text-primary);
    padding-bottom: 4px;
    min-width: 40px;
    text-align: center;
}

.fraction-den {
    padding-top: 4px;
    min-width: 40px;
    text-align: center;
}

/* Emoji groups for visual exercises */
.emoji-group {
    display: inline-flex;
    gap: 4px;
    padding: 4px 8px;
    background: var(--bg-card);
    border-radius: var(--radius-md);
    flex-wrap: wrap;
    justify-content: center;
    max-width: 260px;
}

.emoji-item {
    font-size: 1.6rem;
    transition: all var(--transition-fast);
}

.operator-symbol {
    font-family: var(--font-display);
    font-size: 2rem;
    font-weight: 700;
    color: var(--primary-light);
    display: inline-flex;
    align-items: center;
    padding: 0 var(--space-sm);
}

.equals-symbol {
    font-family: var(--font-display);
    font-size: 2.5rem;
    font-weight: 700;
    color: var(--accent-yellow);
    margin: var(--space-sm) 0;
}

.question-mark {
    font-family: var(--font-display);
    font-size: 3rem;
    font-weight: 700;
    color: var(--accent-pink);
    animation: pulse 1.5s ease-in-out infinite;
}

/* Fraction pie visual */
.fraction-pie-container {
    display: flex;
    gap: var(--space-lg);
    justify-content: center;
    align-items: center;
    margin-bottom: var(--space-md);
}

.fraction-pie {
    width: 80px;
    height: 80px;
    border-radius: 50%;
    position: relative;
    border: 2px solid var(--border-glass);
}

/* --- Responsive --- */
@media (min-width: 768px) {
    .map-content {
        max-width: 900px;
        margin: 0 auto;
    }

    .game-content {
        max-width: 600px;
        margin: 0 auto;
    }

    .stats-content {
        max-width: 700px;
        margin: 0 auto;
    }

    .level-grid {
        grid-template-columns: repeat(10, 1fr);
    }
}

@media (max-width: 480px) {
    .level-grid {
        grid-template-columns: repeat(5, 1fr);
    }

    .map-content {
        padding: var(--space-md);
    }
}

@media (max-width: 360px) {
    .level-grid {
        grid-template-columns: repeat(4, 1fr);
    }
    
    .exercise-question {
        font-size: 2.2rem;
    }
    
    .answer-btn {
        font-size: 1.4rem;
        padding: 16px;
    }
}

/* --- Scrollbar --- */
::-webkit-scrollbar {
    width: 4px;
}

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

::-webkit-scrollbar-thumb {
    background: var(--border-glass);
    border-radius: var(--radius-full);
}

/* --- Selection --- */
::selection {
    background: var(--primary);
    color: white;
}