/* ============================================
   VARIABLES Y RESET
   ============================================ */
:root {
    /* Colores principales */
    --primary: #6366f1;
    --primary-dark: #4f46e5;
    --primary-light: #818cf8;
    --secondary: #ec4899;
    --secondary-dark: #db2777;
    
    /* Colores de estado */
    --success: #10b981;
    --error: #ef4444;
    --warning: #f59e0b;
    --info: #3b82f6;
    
    /* Gradientes */
    --gradient-primary: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    --gradient-success: linear-gradient(135deg, #10b981 0%, #059669 100%);
    --gradient-error: linear-gradient(135deg, #ef4444 0%, #dc2626 100%);
    --gradient-warm: linear-gradient(135deg, #f093fb 0%, #f5576c 100%);
    
    /* Neutrales */
    --bg-primary: #0f172a;
    --bg-secondary: #1e293b;
    --bg-tertiary: #334155;
    --text-primary: #f1f5f9;
    --text-secondary: #cbd5e1;
    --text-muted: #94a3b8;
    
    /* Sombras */
    --shadow-sm: 0 2px 4px rgba(0, 0, 0, 0.1);
    --shadow-md: 0 4px 6px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 10px 15px rgba(0, 0, 0, 0.2);
    --shadow-xl: 0 20px 25px rgba(0, 0, 0, 0.3);
    --shadow-glow: 0 0 20px rgba(99, 102, 241, 0.5);
    
    /* Espaciado */
    --spacing-xs: 0.5rem;
    --spacing-sm: 1rem;
    --spacing-md: 1.5rem;
    --spacing-lg: 2rem;
    --spacing-xl: 3rem;
    
    /* Bordes */
    --radius-sm: 0.5rem;
    --radius-md: 1rem;
    --radius-lg: 1.5rem;
    --radius-full: 9999px;
    
    /* Transiciones */
    --transition-fast: 0.15s ease;
    --transition-normal: 0.3s ease;
    --transition-slow: 0.5s ease;
}

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

html {
    font-size: 16px;
    scroll-behavior: smooth;
}

body {
    font-family: 'Poppins', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    background: var(--bg-primary);
    color: var(--text-primary);
    line-height: 1.6;
    overflow-x: hidden;
    min-height: 100vh;
}

/* ============================================
   PANTALLAS Y CONTENEDORES
   ============================================ */
.screen {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100vh;
    opacity: 0;
    visibility: hidden;
    transition: opacity var(--transition-normal), visibility var(--transition-normal);
    overflow-y: auto;
    z-index: 1;
}

.screen.active {
    opacity: 1;
    visibility: visible;
    z-index: 10;
}

.screen-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: var(--spacing-lg);
    min-height: 100vh;
}

/* ============================================
   PANTALLA DE BIENVENIDA
   ============================================ */
.welcome-container {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    min-height: 100vh;
    text-align: center;
    padding: var(--spacing-lg);
    position: relative;
    z-index: 2;
}

.logo-animation {
    margin-bottom: var(--spacing-lg);
    animation: float 3s ease-in-out infinite;
}

@keyframes float {
    0%, 100% { transform: translateY(0px); }
    50% { transform: translateY(-20px); }
}

.calculator-icon {
    width: 140px;
    height: 140px;
    background: var(--gradient-primary);
    border-radius: var(--radius-lg);
    display: flex;
    align-items: center;
    justify-content: center;
    box-shadow: var(--shadow-glow);
    animation: pulse-glow 2s ease-in-out infinite;
    position: relative;
}

.calculator-icon::before {
    content: '';
    position: absolute;
    inset: -5px;
    background: var(--gradient-primary);
    border-radius: var(--radius-lg);
    opacity: 0.3;
    filter: blur(20px);
    z-index: -1;
}

@keyframes pulse-glow {
    0%, 100% {
        box-shadow: 0 0 30px rgba(99, 102, 241, 0.6);
        transform: scale(1);
    }
    50% {
        box-shadow: 0 0 50px rgba(99, 102, 241, 0.9);
        transform: scale(1.05);
    }
}

.calc-display {
    font-size: 4.5rem;
    color: white;
    text-shadow: 0 0 20px rgba(255, 255, 255, 0.5);
}

.welcome-title {
    margin-bottom: var(--spacing-md);
}

.gradient-text {
    font-size: 3.5rem;
    font-weight: 700;
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    display: block;
    margin-bottom: var(--spacing-xs);
}

.subtitle {
    font-size: 1.8rem;
    color: var(--text-secondary);
    font-weight: 300;
    display: block;
}

.teacher-link {
    font-size: 1.1rem;
    color: var(--text-secondary);
    font-weight: 400;
    display: inline-block;
    margin-top: 0.5rem;
    transition: color 0.3s ease;
    cursor: pointer;
    opacity: 0.8;
}

.teacher-link:hover {
    color: var(--primary);
    opacity: 1;
}

.welcome-description {
    font-size: 1.2rem;
    color: var(--text-secondary);
    margin-bottom: var(--spacing-xl);
    max-width: 600px;
}

.welcome-buttons {
    display: flex;
    gap: var(--spacing-md);
    margin-bottom: var(--spacing-xl);
    flex-wrap: wrap;
    justify-content: center;
}

.stats-preview {
    display: flex;
    gap: var(--spacing-lg);
    padding: var(--spacing-lg);
    background: rgba(255, 255, 255, 0.05);
    border-radius: var(--radius-lg);
    backdrop-filter: blur(10px);
    border: 1px solid rgba(255, 255, 255, 0.1);
}

.stat-item {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: var(--spacing-xs);
}

.stat-value {
    font-size: 2rem;
    font-weight: 700;
    color: var(--primary-light);
}

.stat-label {
    font-size: 0.9rem;
    color: var(--text-muted);
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

/* Formas flotantes animadas */
.floating-shapes {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    pointer-events: none;
    z-index: 1;
}

.shape {
    position: absolute;
    border-radius: 50%;
    opacity: 0.1;
    animation: float-random 20s ease-in-out infinite;
}

.shape-1 {
    width: 300px;
    height: 300px;
    background: var(--primary);
    top: 10%;
    left: 10%;
    animation-delay: 0s;
}

.shape-2 {
    width: 200px;
    height: 200px;
    background: var(--secondary);
    top: 50%;
    right: 10%;
    animation-delay: 5s;
}

.shape-3 {
    width: 250px;
    height: 250px;
    background: var(--info);
    bottom: 10%;
    left: 50%;
    animation-delay: 10s;
}

@keyframes float-random {
    0%, 100% {
        transform: translate(0, 0) rotate(0deg);
    }
    33% {
        transform: translate(50px, -50px) rotate(120deg);
    }
    66% {
        transform: translate(-50px, 50px) rotate(240deg);
    }
}

/* ============================================
   BOTONES
   ============================================ */
.btn {
    padding: 0.75rem 1.5rem;
    border: none;
    border-radius: var(--radius-md);
    font-family: inherit;
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    transition: all var(--transition-normal);
    display: inline-flex;
    align-items: center;
    gap: var(--spacing-xs);
    text-decoration: none;
    box-shadow: var(--shadow-md);
}

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

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
}

.btn-primary:active {
    transform: translateY(0);
}

.btn-secondary {
    background: rgba(255, 255, 255, 0.1);
    color: var(--text-primary);
    border: 1px solid rgba(255, 255, 255, 0.2);
}

.btn-secondary:hover {
    background: rgba(255, 255, 255, 0.15);
    transform: translateY(-2px);
}

.btn-large {
    padding: 1rem 2rem;
    font-size: 1.1rem;
}

.btn-icon {
    font-size: 1.3em;
}

.btn-back {
    position: fixed;
    top: var(--spacing-md);
    left: var(--spacing-md);
    padding: 0.75rem 1.5rem;
    background: rgba(255, 255, 255, 0.1);
    border: 1px solid rgba(255, 255, 255, 0.2);
    border-radius: var(--radius-md);
    color: var(--text-primary);
    font-family: inherit;
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    transition: all var(--transition-normal);
    z-index: 100;
    backdrop-filter: blur(10px);
}

.btn-back:hover {
    background: rgba(255, 255, 255, 0.15);
    transform: translateX(-3px);
}

/* ============================================
   SELECCIÓN DE MODO
   ============================================ */
.screen-title {
    font-size: 2.5rem;
    font-weight: 700;
    text-align: center;
    margin-bottom: var(--spacing-xl);
    margin-top: var(--spacing-xl);
}

.mode-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: var(--spacing-lg);
    margin-top: var(--spacing-xl);
}

.mode-card {
    background: rgba(255, 255, 255, 0.05);
    border: 1px solid rgba(255, 255, 255, 0.1);
    border-radius: var(--radius-lg);
    padding: var(--spacing-xl);
    cursor: pointer;
    transition: all var(--transition-normal);
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-md);
    text-align: center;
}

.mode-card:hover {
    transform: translateY(-5px);
    border-color: var(--primary);
    background: rgba(99, 102, 241, 0.1);
    box-shadow: var(--shadow-xl);
}

.mode-icon {
    font-size: 4rem;
    text-align: center;
    margin-bottom: var(--spacing-sm);
    color: var(--primary-light);
    transition: all var(--transition-normal);
}

.mode-icon i {
    display: inline-block;
    transition: transform var(--transition-normal);
}

.mode-card:hover .mode-icon i {
    transform: scale(1.2) rotate(5deg);
}

.mode-card h3 {
    font-size: 1.4rem;
    color: var(--primary-light);
    text-align: center;
    margin: 0;
    line-height: 1.4;
}

.mode-card p {
    color: var(--text-secondary);
    text-align: center;
    font-size: 0.95rem;
    margin: 0;
    line-height: 1.6;
}

.mode-example {
    background: rgba(0, 0, 0, 0.3);
    padding: var(--spacing-md);
    border-radius: var(--radius-sm);
    font-size: 0.9rem;
    color: var(--text-muted);
    font-style: italic;
    border-left: 3px solid var(--primary);
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-xs);
    width: 100%;
    text-align: center;
}

.mode-example i {
    color: var(--warning);
    font-size: 1rem;
    margin-top: 2px;
    flex-shrink: 0;
}

/* ============================================
   TUTORIAL
   ============================================ */
.tutorial-container {
    display: grid;
    grid-template-columns: 250px 1fr;
    gap: var(--spacing-xl);
    margin-top: var(--spacing-xl);
}

.tutorial-sidebar {
    background: rgba(255, 255, 255, 0.05);
    border-radius: var(--radius-lg);
    padding: var(--spacing-md);
    height: fit-content;
    position: sticky;
    top: var(--spacing-md);
    z-index: 10;
}

.tutorial-content {
    min-width: 0;
    overflow-x: hidden;
}

.tutorial-sidebar h3 {
    margin-bottom: var(--spacing-md);
    color: var(--text-secondary);
    font-size: 0.9rem;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    display: flex;
    align-items: center;
    gap: var(--spacing-xs);
}

.tutorial-sidebar h3 i {
    font-size: 1rem;
}

.tutorial-tab {
    width: 100%;
    padding: var(--spacing-md);
    background: transparent;
    border: none;
    border-radius: var(--radius-sm);
    color: var(--text-secondary);
    font-family: inherit;
    font-size: 1rem;
    text-align: left;
    cursor: pointer;
    transition: all var(--transition-fast);
    margin-bottom: var(--spacing-xs);
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
}

.tutorial-tab i {
    font-size: 1.2rem;
    width: 24px;
    text-align: center;
}

.tutorial-tab:hover {
    background: rgba(255, 255, 255, 0.05);
    transform: translateX(5px);
}

.tutorial-tab.active {
    background: var(--gradient-primary);
    color: white;
    font-weight: 600;
    transform: translateX(5px);
}

.tutorial-content {
    background: rgba(255, 255, 255, 0.05);
    border-radius: var(--radius-lg);
    padding: var(--spacing-xl);
}

.tutorial-section {
    display: none;
}

.tutorial-section.active {
    display: block;
    animation: fadeIn 0.5s ease;
}

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

.tutorial-section h2 {
    font-size: 2rem;
    margin-bottom: var(--spacing-lg);
    color: var(--primary-light);
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
}

.tutorial-section h2 i {
    font-size: 1.8rem;
}

.tutorial-block {
    margin-bottom: var(--spacing-lg);
}

.tutorial-block h3 {
    font-size: 1.4rem;
    margin-bottom: var(--spacing-md);
    color: var(--text-primary);
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
}

.tutorial-block h3 i {
    color: var(--warning);
    font-size: 1.3rem;
}

.tutorial-block p {
    color: var(--text-secondary);
    font-size: 1rem;
    line-height: 1.8;
}

.tutorial-block.highlight {
    background: rgba(99, 102, 241, 0.1);
    padding: var(--spacing-lg);
    border-radius: var(--radius-md);
    border-left: 4px solid var(--primary);
}

.example-box {
    margin-top: var(--spacing-md);
}

.example-problem {
    font-size: 1.1rem;
    color: var(--text-primary);
    font-weight: 600;
    margin-bottom: var(--spacing-lg);
    padding: var(--spacing-md);
    background: rgba(0, 0, 0, 0.3);
    border-radius: var(--radius-sm);
}

.step-by-step {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-lg);
}

.step {
    display: flex;
    gap: var(--spacing-md);
    align-items: flex-start;
}

.step-number {
    width: 40px;
    height: 40px;
    background: var(--gradient-primary);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 700;
    font-size: 1.2rem;
    flex-shrink: 0;
}

.step-content {
    flex: 1;
}

.step-content h4 {
    font-size: 1.1rem;
    margin-bottom: var(--spacing-sm);
    color: var(--primary-light);
}

.rule-of-three-visual {
    background: rgba(0, 0, 0, 0.3);
    padding: var(--spacing-md);
    border-radius: var(--radius-sm);
    margin-top: var(--spacing-sm);
}

.proportion-line {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: var(--spacing-sm);
    margin: var(--spacing-xs) 0;
    font-size: 1.1rem;
}

.proportion-line.highlight {
    background: rgba(99, 102, 241, 0.2);
    border-radius: var(--radius-sm);
    font-weight: 600;
}

.formula {
    background: rgba(16, 185, 129, 0.2);
    padding: var(--spacing-md);
    border-radius: var(--radius-sm);
    font-size: 1.3rem;
    font-weight: 700;
    text-align: center;
    color: var(--success);
    margin-top: var(--spacing-sm);
    font-family: 'Courier New', monospace;
}

.calculation {
    background: rgba(0, 0, 0, 0.3);
    padding: var(--spacing-md);
    border-radius: var(--radius-sm);
    font-size: 1.2rem;
    text-align: center;
    margin-top: var(--spacing-sm);
    font-family: 'Courier New', monospace;
}

.result {
    color: var(--success);
    font-weight: 700;
    font-size: 1.4em;
}

.note {
    margin-top: var(--spacing-sm);
    padding: var(--spacing-sm);
    background: rgba(59, 130, 246, 0.1);
    border-left: 3px solid var(--info);
    border-radius: var(--radius-sm);
    font-size: 0.95rem;
    color: var(--text-secondary);
}

.tip {
    background: rgba(245, 158, 11, 0.1);
    padding: var(--spacing-md);
    border-radius: var(--radius-sm);
    border-left: 4px solid var(--warning);
    font-size: 1rem;
    color: var(--text-secondary);
    font-style: italic;
    line-height: 1.8;
}

.magnitudes-table {
    overflow-x: auto;
    margin-top: var(--spacing-md);
}

.magnitudes-table table {
    width: 100%;
    border-collapse: collapse;
    background: rgba(0, 0, 0, 0.3);
    border-radius: var(--radius-sm);
}

.magnitudes-table th,
.magnitudes-table td {
    padding: var(--spacing-sm);
    text-align: center;
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
}

.magnitudes-table th {
    background: rgba(99, 102, 241, 0.2);
    font-weight: 600;
    color: var(--primary-light);
}

.magnitudes-table .inverse {
    color: var(--secondary);
    font-weight: 600;
}

/* ============================================
   PANTALLA DE JUEGO
   ============================================ */
.game-container {
    max-width: 900px;
    margin: 0 auto;
    padding: var(--spacing-lg);
    padding-top: 100px;
}

.game-header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    background: rgba(15, 23, 42, 0.95);
    backdrop-filter: blur(10px);
    padding: var(--spacing-md);
    z-index: 50;
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
}

.game-info {
    display: flex;
    justify-content: center;
    gap: var(--spacing-xl);
    margin: var(--spacing-md) 0;
}

.info-item {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 0.25rem;
}

.info-label {
    font-size: 0.8rem;
    color: var(--text-muted);
    text-transform: uppercase;
    letter-spacing: 0.05em;
    display: flex;
    align-items: center;
    gap: 0.3rem;
}

.info-label i {
    font-size: 1rem;
}

.info-value {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--primary-light);
}

.progress-bar {
    height: 6px;
    background: rgba(255, 255, 255, 0.1);
    border-radius: var(--radius-full);
    overflow: hidden;
    margin-top: var(--spacing-md);
}

.progress-fill {
    height: 100%;
    background: var(--gradient-primary);
    transition: width var(--transition-normal);
    width: 0%;
}

.exercise-area {
    margin-top: var(--spacing-lg);
}

.exercise-type {
    text-align: center;
    font-size: 1.2rem;
    color: var(--text-primary);
    margin-bottom: var(--spacing-md);
    font-weight: 600;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-sm);
    background: rgba(99, 102, 241, 0.1);
    padding: var(--spacing-md);
    border-radius: var(--radius-md);
    border: 1px solid rgba(99, 102, 241, 0.3);
}

.exercise-type i {
    font-size: 1.4rem;
    color: var(--primary-light);
}

.exercise-card {
    background: rgba(255, 255, 255, 0.05);
    border: 1px solid rgba(255, 255, 255, 0.1);
    border-radius: var(--radius-lg);
    padding: var(--spacing-xl);
    box-shadow: var(--shadow-xl);
}

.exercise-problem {
    font-size: 1.3rem;
    font-weight: 600;
    color: var(--text-primary);
    text-align: center;
    margin-bottom: var(--spacing-xl);
    line-height: 1.6;
}

.exercise-visual {
    background: rgba(0, 0, 0, 0.3);
    padding: var(--spacing-lg);
    border-radius: var(--radius-md);
    margin-bottom: var(--spacing-xl);
}

.answer-section {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-md);
}

.answer-label {
    font-size: 1.1rem;
    font-weight: 600;
    color: var(--text-primary);
}

.answer-input-group {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
}

.answer-input {
    flex: 1;
    padding: var(--spacing-md);
    font-size: 1.5rem;
    font-family: 'Courier New', monospace;
    font-weight: 700;
    background: rgba(0, 0, 0, 0.3);
    border: 2px solid rgba(255, 255, 255, 0.2);
    border-radius: var(--radius-md);
    color: var(--text-primary);
    text-align: center;
    transition: all var(--transition-normal);
}

.answer-input:focus {
    outline: none;
    border-color: var(--primary);
    box-shadow: 0 0 0 4px rgba(99, 102, 241, 0.2);
}

.answer-unit {
    font-size: 1.2rem;
    color: var(--text-secondary);
    min-width: 80px;
}

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

/* Nuevo sistema de opciones múltiples */
.exercise-header-info {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: var(--spacing-md);
    padding: var(--spacing-md);
    background: rgba(255, 255, 255, 0.05);
    border-radius: var(--radius-md);
}

.player-name {
    font-size: 1.1rem;
    font-weight: 600;
    color: var(--primary-light);
}

.player-name i {
    margin-right: var(--spacing-xs);
}

.question-counter {
    font-size: 1rem;
    color: var(--text-secondary);
    font-weight: 600;
}

.options-container {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: var(--spacing-md);
    margin-top: var(--spacing-xl);
}

.option-btn {
    padding: var(--spacing-lg);
    background: rgba(255, 255, 255, 0.05);
    border: 2px solid rgba(255, 255, 255, 0.1);
    border-radius: var(--radius-md);
    color: var(--text-primary);
    font-size: 1.3rem;
    font-weight: 700;
    cursor: pointer;
    transition: all var(--transition-normal);
    min-height: 80px;
    display: flex;
    align-items: center;
    justify-content: center;
}

.option-btn:hover:not(.correct):not(.incorrect):not(.disabled) {
    background: rgba(99, 102, 241, 0.2);
    border-color: var(--primary);
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
}

.option-btn.correct {
    background: rgba(16, 185, 129, 0.2);
    border-color: var(--success);
    color: var(--success);
    animation: pulse 0.5s ease;
}

.option-btn.incorrect {
    background: rgba(239, 68, 68, 0.2);
    border-color: var(--error);
    color: var(--error);
    animation: shake 0.5s ease;
}

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

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

@media (max-width: 768px) {
    .options-container {
        grid-template-columns: 1fr;
    }
    
    .challenge-phases {
        grid-template-columns: 1fr !important;
    }
}

/* ============================================
   PANTALLA DE RESULTADOS
   ============================================ */
.results-container {
    max-width: 700px;
    margin: 0 auto;
    padding: var(--spacing-xl);
    text-align: center;
}

.results-animation {
    font-size: 8rem;
    margin-bottom: var(--spacing-lg);
    animation: bounceIn 0.8s ease;
}

@keyframes bounceIn {
    0% {
        transform: scale(0);
        opacity: 0;
    }
    50% {
        transform: scale(1.2);
    }
    100% {
        transform: scale(1);
        opacity: 1;
    }
}

.results-title {
    font-size: 3rem;
    font-weight: 700;
    margin-bottom: var(--spacing-md);
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.results-message {
    font-size: 1.2rem;
    color: var(--text-secondary);
    margin-bottom: var(--spacing-xl);
}

.results-stats {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
    gap: var(--spacing-md);
    margin-bottom: var(--spacing-xl);
}

.result-stat {
    background: rgba(255, 255, 255, 0.05);
    border: 1px solid rgba(255, 255, 255, 0.1);
    border-radius: var(--radius-lg);
    padding: var(--spacing-lg);
}

.result-stat-icon {
    font-size: 3rem;
    margin-bottom: var(--spacing-sm);
}

.result-stat-icon i {
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.result-stat-value {
    font-size: 2.5rem;
    font-weight: 700;
    color: var(--primary-light);
    margin-bottom: var(--spacing-xs);
}

.result-stat-label {
    font-size: 0.9rem;
    color: var(--text-muted);
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

.results-buttons {
    display: flex;
    gap: var(--spacing-md);
    justify-content: center;
    flex-wrap: wrap;
}

/* ============================================
   MODAL DE FEEDBACK
   ============================================ */
.modal {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.8);
    display: none;
    align-items: center;
    justify-content: center;
    z-index: 1000;
    backdrop-filter: blur(5px);
}

.modal.show {
    display: flex;
    animation: fadeIn 0.3s ease;
}

.modal-content {
    background: var(--bg-secondary);
    border: 1px solid rgba(255, 255, 255, 0.1);
    border-radius: var(--radius-lg);
    padding: var(--spacing-xl);
    max-width: 500px;
    width: 90%;
    text-align: center;
    animation: slideUp 0.3s ease;
}

@keyframes slideUp {
    from {
        opacity: 0;
        transform: translateY(50px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.feedback-icon {
    font-size: 5rem;
    margin-bottom: var(--spacing-md);
}

.feedback-content h3 {
    font-size: 2rem;
    margin-bottom: var(--spacing-md);
}

.feedback-content p {
    color: var(--text-secondary);
    font-size: 1.1rem;
    margin-bottom: var(--spacing-md);
}

.feedback-explanation {
    background: rgba(0, 0, 0, 0.3);
    padding: var(--spacing-md);
    border-radius: var(--radius-sm);
    text-align: left;
    margin-top: var(--spacing-md);
}

/* ============================================
   CANVAS DE PARTÍCULAS
   ============================================ */
#particlesCanvas {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    pointer-events: none;
    z-index: 9999;
}

/* ============================================
   CONCEPTOS FUNDAMENTALES
   ============================================ */
.concept-intro {
    background: linear-gradient(135deg, rgba(99, 102, 241, 0.2), rgba(236, 72, 153, 0.2));
    padding: var(--spacing-lg);
    border-radius: var(--radius-lg);
    border: 2px solid var(--primary);
    margin-bottom: var(--spacing-xl);
    text-align: center;
}

.concept-card {
    background: rgba(255, 255, 255, 0.03);
    border: 1px solid rgba(255, 255, 255, 0.1);
    border-radius: var(--radius-lg);
    margin-bottom: var(--spacing-xl);
    overflow: hidden;
    transition: all var(--transition-normal);
}

.concept-card:hover {
    border-color: var(--primary);
    box-shadow: var(--shadow-xl);
    transform: translateY(-2px);
}

.concept-header {
    background: var(--gradient-primary);
    padding: var(--spacing-lg);
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-md);
}

.concept-header i {
    font-size: 1.8rem;
    flex-shrink: 0;
}

.concept-header h3 {
    margin: 0;
    font-size: 1.5rem;
    line-height: 1.3;
    text-align: center;
}

.concept-body {
    padding: var(--spacing-lg);
}

.concept-explain {
    font-size: 1.15rem;
    line-height: 1.9;
    margin-bottom: var(--spacing-lg);
    color: var(--text-primary);
}

.highlight-text {
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    font-weight: 700;
    font-size: 1.1em;
}

.concept-example {
    background: rgba(0, 0, 0, 0.3);
    padding: var(--spacing-lg);
    border-radius: var(--radius-md);
    margin: var(--spacing-md) 0;
    border-left: 4px solid var(--primary);
}

.concept-example h4 {
    color: var(--primary-light);
    margin-bottom: var(--spacing-md);
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
}

.visual-proportion {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-md);
    margin: var(--spacing-md) 0;
    flex-wrap: wrap;
}

.prop-box {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    padding: var(--spacing-md);
    background: rgba(99, 102, 241, 0.2);
    border-radius: var(--radius-sm);
}

.prop-value {
    font-weight: 600;
    color: var(--text-primary);
    font-size: 1.1rem;
}

.prop-arrow {
    font-size: 1.5rem;
    color: var(--primary-light);
}

.prop-equals {
    font-size: 2rem;
    font-weight: 700;
    color: var(--success);
}

.concept-note {
    margin-top: var(--spacing-md);
    padding: var(--spacing-sm);
    background: rgba(16, 185, 129, 0.1);
    border-radius: var(--radius-sm);
    border-left: 3px solid var(--success);
    display: flex;
    align-items: flex-start;
    gap: var(--spacing-sm);
}

.concept-note i {
    color: var(--success);
    margin-top: 4px;
}

.key-insight {
    background: rgba(245, 158, 11, 0.15);
    border: 2px solid var(--warning);
    border-radius: var(--radius-md);
    padding: var(--spacing-lg);
    margin-top: var(--spacing-lg);
    display: flex;
    align-items: flex-start;
    gap: var(--spacing-md);
}

.key-insight i {
    font-size: 1.8rem;
    color: var(--warning);
    margin-top: 2px;
    flex-shrink: 0;
}

.key-insight strong {
    font-size: 1.1rem;
}

.key-insight {
    font-size: 1.05rem;
    line-height: 1.8;
}

.magnitudes-examples {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-md);
    margin: var(--spacing-md) 0;
}

.mag-item {
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
    padding: var(--spacing-md);
    background: rgba(255, 255, 255, 0.05);
    border-radius: var(--radius-sm);
    border-left: 3px solid;
}

.mag-item:nth-child(1) { border-left-color: #10b981; }
.mag-item:nth-child(2) { border-left-color: #f59e0b; }
.mag-item:nth-child(3) { border-left-color: #3b82f6; }
.mag-item:nth-child(4) { border-left-color: #ec4899; }
.mag-item:nth-child(5) { border-left-color: #8b5cf6; }

.mag-item i {
    font-size: 1.5rem;
}

.direct-rules, .inverse-rules {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: var(--spacing-md);
    margin: var(--spacing-md) 0;
}

.rule-box {
    padding: var(--spacing-lg);
    background: rgba(16, 185, 129, 0.1);
    border: 2px solid var(--success);
    border-radius: var(--radius-md);
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: var(--spacing-sm);
    text-align: center;
}

.rule-box p {
    font-size: 1.05rem;
    line-height: 1.6;
}

.rule-box.inverse {
    background: rgba(236, 72, 153, 0.1);
    border-color: var(--secondary);
}

.rule-box i {
    font-size: 2rem;
    color: var(--success);
}

.rule-box.inverse i {
    color: var(--secondary);
}

.example-item {
    margin: var(--spacing-md) 0;
    padding: var(--spacing-md);
    background: rgba(59, 130, 246, 0.1);
    border-radius: var(--radius-sm);
    border-left: 3px solid var(--info);
}

.example-item.inverse {
    background: rgba(236, 72, 153, 0.1);
    border-left-color: var(--secondary);
}

.example-item strong {
    display: block;
    margin-bottom: var(--spacing-xs);
    color: var(--primary-light);
    font-size: 1.15rem;
}

.example-item p {
    font-size: 1.05rem;
    line-height: 1.7;
}

.visual-example {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-xs);
    margin-top: var(--spacing-sm);
    padding: var(--spacing-sm);
    background: rgba(0, 0, 0, 0.3);
    border-radius: var(--radius-sm);
    font-family: 'Courier New', monospace;
}

.formula-box {
    background: rgba(16, 185, 129, 0.15);
    border: 2px solid var(--success);
    border-radius: var(--radius-lg);
    padding: var(--spacing-lg);
    margin: var(--spacing-lg) 0;
}

.formula-box.inverse {
    background: rgba(236, 72, 153, 0.15);
    border-color: var(--secondary);
}

.formula-box h4 {
    margin-bottom: var(--spacing-md);
    color: var(--success);
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
}

.formula-box.inverse h4 {
    color: var(--secondary);
}

.formula-display {
    background: rgba(0, 0, 0, 0.4);
    padding: var(--spacing-xl);
    border-radius: var(--radius-md);
    text-align: center;
    font-size: 2rem;
    font-weight: 700;
    font-family: 'Courier New', monospace;
    color: var(--success);
    margin: var(--spacing-md) 0;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-sm);
    min-height: 80px;
}

.formula-box.inverse .formula-display {
    color: var(--secondary);
}

.formula-fraction {
    display: inline-flex;
    flex-direction: column;
    vertical-align: middle;
    text-align: center;
    margin: 0 var(--spacing-sm);
    font-size: 1.6rem;
}

.formula-fraction span {
    padding: var(--spacing-xs) var(--spacing-sm);
}

.formula-fraction span:first-child {
    border-bottom: 3px solid currentColor;
    padding-bottom: var(--spacing-xs);
    margin-bottom: var(--spacing-xs);
}

.formula-explain {
    font-size: 1rem;
    color: var(--text-secondary);
    line-height: 1.8;
    margin-top: var(--spacing-md);
}

.important-note {
    margin-top: var(--spacing-md);
    padding: var(--spacing-md);
    background: rgba(245, 158, 11, 0.2);
    border: 1px solid var(--warning);
    border-radius: var(--radius-sm);
    display: flex;
    align-items: flex-start;
    gap: var(--spacing-sm);
}

.important-note i {
    color: var(--warning);
    font-size: 1.2rem;
    margin-top: 2px;
}

.compound-explain {
    background: rgba(99, 102, 241, 0.1);
    padding: var(--spacing-md);
    border-radius: var(--radius-md);
    margin: var(--spacing-md) 0;
}

.compound-steps {
    margin: var(--spacing-lg) 0;
}

.compound-steps h4 {
    margin-bottom: var(--spacing-md);
    color: var(--primary-light);
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
}

.compound-step {
    display: flex;
    gap: var(--spacing-md);
    margin: var(--spacing-md) 0;
    padding: var(--spacing-lg);
    background: rgba(255, 255, 255, 0.03);
    border-radius: var(--radius-md);
    border-left: 3px solid var(--primary);
}

.compound-step strong {
    font-size: 1.1rem;
}

.compound-step p {
    font-size: 1.05rem;
    line-height: 1.7;
    margin-top: var(--spacing-xs);
}

.step-num {
    width: 40px;
    height: 40px;
    background: var(--gradient-primary);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 700;
    font-size: 1.3rem;
    flex-shrink: 0;
}

.compound-visual {
    margin: var(--spacing-md) 0;
}

.analysis-table {
    width: 100%;
    margin: var(--spacing-md) 0;
    border-collapse: collapse;
    background: rgba(0, 0, 0, 0.3);
    border-radius: var(--radius-sm);
    overflow: hidden;
}

.analysis-table th,
.analysis-table td {
    padding: var(--spacing-sm);
    text-align: left;
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
}

.analysis-table th {
    background: rgba(99, 102, 241, 0.2);
    font-weight: 600;
    color: var(--primary-light);
}

/* Tabla horizontal para regla compuesta */
.analysis-table-horizontal {
    width: 100%;
    margin: var(--spacing-md) 0;
    border-collapse: collapse;
    background: rgba(0, 0, 0, 0.3);
    border-radius: var(--radius-sm);
    overflow: hidden;
}

.analysis-table-horizontal th {
    background: rgba(99, 102, 241, 0.2);
    font-weight: 700;
    color: var(--primary-light);
    padding: var(--spacing-md);
    text-align: center;
    border: 1px solid rgba(255, 255, 255, 0.1);
    font-size: 1.05rem;
}

.analysis-table-horizontal td {
    padding: var(--spacing-md);
    text-align: center;
    border: 1px solid rgba(255, 255, 255, 0.1);
    font-size: 1.1rem;
    font-weight: 500;
}

.analysis-table-horizontal tr:nth-child(1) th {
    background: rgba(99, 102, 241, 0.3);
}

.analysis-table-horizontal tr:nth-child(2) td {
    background: rgba(16, 185, 129, 0.1);
}

.analysis-table-horizontal tr:nth-child(3) td {
    background: rgba(59, 130, 246, 0.1);
}

.analysis-table-horizontal tr:nth-child(4) td {
    background: rgba(236, 72, 153, 0.1);
}

.search-label {
    display: inline-block;
    background: var(--gradient-primary);
    color: white;
    padding: 2px 8px;
    border-radius: var(--radius-sm);
    font-size: 0.8rem;
    margin-left: var(--spacing-xs);
    font-weight: 700;
}

.inverse-rel {
    color: var(--secondary);
    font-weight: 700;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-xs);
}

.inverse-rel i {
    font-size: 1.2rem;
}

.solution-compound {
    background: rgba(16, 185, 129, 0.05);
    padding: var(--spacing-lg);
    border-radius: var(--radius-md);
    margin-top: var(--spacing-lg);
    border: 2px solid rgba(16, 185, 129, 0.3);
}

.analysis-explanation {
    background: rgba(99, 102, 241, 0.1);
    padding: var(--spacing-md);
    border-radius: var(--radius-sm);
    margin-bottom: var(--spacing-md);
}

.analysis-explanation ul {
    margin: var(--spacing-sm) 0 0 var(--spacing-lg);
    list-style: none;
}

.analysis-explanation li {
    margin: var(--spacing-xs) 0;
    padding-left: var(--spacing-md);
    position: relative;
}

.analysis-explanation li::before {
    content: "→";
    position: absolute;
    left: 0;
    color: var(--primary-light);
    font-weight: 700;
}

.analysis-explanation code {
    background: rgba(0, 0, 0, 0.4);
    padding: 2px 8px;
    border-radius: var(--radius-sm);
    font-family: 'Courier New', monospace;
    color: var(--success);
    font-weight: 700;
}

.solution-title {
    font-size: 1.1rem;
    margin: var(--spacing-md) 0;
    color: var(--primary-light);
}

.calculation-steps {
    font-size: 1.05rem;
    margin: var(--spacing-lg) 0 var(--spacing-md) 0;
    color: var(--primary-light);
}

.formula-display-compound {
    background: rgba(0, 0, 0, 0.5);
    padding: var(--spacing-xl);
    border-radius: var(--radius-md);
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-md);
    flex-wrap: wrap;
    margin: var(--spacing-md) 0;
    min-height: 100px;
}

.formula-part {
    font-size: 1.8rem;
    font-weight: 700;
    color: var(--text-primary);
    font-family: 'Courier New', monospace;
}

.formula-operator {
    font-size: 2rem;
    font-weight: 700;
    color: var(--primary-light);
}

.formula-fraction-group {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: var(--spacing-xs);
}

.fraction-label {
    font-size: 0.75rem;
    background: rgba(16, 185, 129, 0.3);
    color: var(--success);
    padding: 2px 8px;
    border-radius: var(--radius-sm);
    font-weight: 700;
    text-transform: uppercase;
}

.fraction-label.inverse-label {
    background: rgba(236, 72, 153, 0.3);
    color: var(--secondary);
}

.formula-fraction-compound {
    display: flex;
    flex-direction: column;
    align-items: center;
    font-family: 'Courier New', monospace;
    font-size: 1.6rem;
    font-weight: 700;
    color: var(--text-primary);
}

.formula-fraction-compound .numerator {
    padding: var(--spacing-xs) var(--spacing-sm);
    color: var(--success);
}

.formula-fraction-compound .divider {
    width: 100%;
    height: 3px;
    background: var(--primary-light);
    margin: 2px 0;
}

.formula-fraction-compound .denominator {
    padding: var(--spacing-xs) var(--spacing-sm);
    color: var(--info);
}

.result-fraction {
    border: 2px solid var(--success);
    padding: var(--spacing-sm);
    border-radius: var(--radius-sm);
    background: rgba(16, 185, 129, 0.1);
}

.result-final {
    font-size: 2rem;
    color: var(--success);
    font-weight: 700;
}

.formula-hint {
    background: rgba(245, 158, 11, 0.1);
    padding: var(--spacing-md);
    border-radius: var(--radius-sm);
    border-left: 3px solid var(--warning);
    margin-top: var(--spacing-md);
    font-size: 1.05rem;
    display: flex;
    align-items: flex-start;
    gap: var(--spacing-sm);
}

.formula-hint i {
    color: var(--warning);
    margin-top: 2px;
}

.formula-explanation {
    background: rgba(59, 130, 246, 0.1);
    padding: var(--spacing-md);
    border-radius: var(--radius-sm);
    border-left: 3px solid var(--info);
    margin: var(--spacing-md) 0;
    font-size: 1.05rem;
}

.formula-explanation i {
    color: var(--info);
}

.explain-formula {
    font-size: 0.95rem;
    color: var(--text-muted);
    font-style: italic;
    text-align: center;
    margin-top: var(--spacing-sm);
}

/* Estilos para explicación detallada de regla compuesta */
.compound-intro {
    background: rgba(99, 102, 241, 0.05);
    padding: var(--spacing-lg);
    border-radius: var(--radius-md);
    border-left: 4px solid var(--primary);
    margin-bottom: var(--spacing-xl);
}

.compound-example-section {
    margin-top: var(--spacing-xl);
}

.compound-example-section h4 {
    color: var(--primary-light);
    margin-bottom: var(--spacing-md);
    font-size: 1.2rem;
}

.example-problem {
    background: linear-gradient(135deg, rgba(99, 102, 241, 0.1), rgba(139, 92, 246, 0.1));
    padding: var(--spacing-lg);
    border-radius: var(--radius-md);
    border: 2px solid rgba(99, 102, 241, 0.3);
    margin-bottom: var(--spacing-xl);
}

.problem-text {
    font-size: 1.15rem;
    line-height: 1.8;
    margin: 0;
}

.solution-steps {
    margin-top: var(--spacing-xl);
}

.solution-steps > h4 {
    color: var(--primary-light);
    margin-bottom: var(--spacing-lg);
    font-size: 1.2rem;
}

.step-detail {
    background: rgba(0, 0, 0, 0.3);
    padding: var(--spacing-lg);
    border-radius: var(--radius-md);
    margin-bottom: var(--spacing-lg);
    border-left: 4px solid var(--primary);
}

.step-header {
    display: flex;
    align-items: flex-start;
    gap: var(--spacing-sm);
    margin-bottom: var(--spacing-md);
    font-size: 1.1rem;
    line-height: 1.7;
}

.step-bullet {
    color: var(--primary-light);
    font-size: 1.5rem;
    font-weight: 700;
    flex-shrink: 0;
}

.highlight-text {
    background: linear-gradient(135deg, var(--primary), var(--secondary));
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
    font-weight: 700;
}

.highlight-search {
    color: var(--secondary);
    font-weight: 700;
}

.highlight-important {
    color: var(--warning);
    font-weight: 700;
    font-size: 1.1em;
}

.step-content {
    padding-left: calc(var(--spacing-md) + 1.5rem);
}

.data-table {
    width: 100%;
    border-collapse: collapse;
    background: rgba(0, 0, 0, 0.4);
    border-radius: var(--radius-sm);
    overflow: hidden;
    margin: var(--spacing-md) 0;
}

.data-table th {
    background: rgba(99, 102, 241, 0.3);
    font-weight: 700;
    padding: var(--spacing-md);
    text-align: center;
    border: 1px solid rgba(255, 255, 255, 0.1);
}

.data-table td {
    padding: var(--spacing-md);
    text-align: center;
    border: 1px solid rgba(255, 255, 255, 0.1);
    font-size: 1.1rem;
    font-weight: 600;
}

.comparison-box {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-xl);
    margin: var(--spacing-lg) 0;
}

.comparison-item {
    background: rgba(0, 0, 0, 0.4);
    padding: var(--spacing-lg);
    border-radius: var(--radius-md);
    border: 2px solid rgba(99, 102, 241, 0.2);
}

.comparison-title {
    font-size: 1.1rem;
    font-weight: 700;
    color: var(--primary-light);
    margin-bottom: var(--spacing-md);
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
}

.comparison-content {
    margin-top: var(--spacing-md);
}

.comparison-diagram {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-lg);
    flex-wrap: wrap;
    margin-bottom: var(--spacing-md);
}

.diagram-col {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: var(--spacing-xs);
    padding: var(--spacing-md);
    background: rgba(99, 102, 241, 0.1);
    border-radius: var(--radius-sm);
    min-width: 100px;
}

.diagram-label {
    font-size: 0.85rem;
    color: var(--text-muted);
    font-weight: 600;
    text-transform: uppercase;
}

.diagram-value {
    font-size: 1.3rem;
    font-weight: 700;
    color: var(--text-primary);
}

.arrow-down {
    color: var(--primary-light);
    margin-left: var(--spacing-xs);
}

.diagram-arrow {
    font-size: 2rem;
    color: var(--primary-light);
}

.diagram-conclusion {
    width: 100%;
    margin-top: var(--spacing-md);
}

.relation-box {
    padding: var(--spacing-lg);
    border-radius: var(--radius-md);
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: var(--spacing-md);
    text-align: center;
}

.direct-box {
    background: rgba(16, 185, 129, 0.15);
    border: 2px solid rgba(16, 185, 129, 0.4);
}

.inverse-box {
    background: rgba(236, 72, 153, 0.15);
    border: 2px solid rgba(236, 72, 153, 0.4);
}

.relation-box i {
    font-size: 1.5rem;
}

.direct-box i {
    color: var(--success);
}

.inverse-box i {
    color: var(--secondary);
}

.relation-box > div {
    font-size: 1.05rem;
    line-height: 1.7;
}

.fraction-result {
    font-size: 1.2rem;
    font-weight: 700;
    margin-top: var(--spacing-sm);
}

.fraction-inline {
    display: inline-block;
    margin: 0 var(--spacing-xs);
}

.fraction-inline sup {
    color: var(--success);
    font-size: 1.1em;
}

.fraction-inline sub {
    color: var(--info);
    font-size: 1.1em;
}

.important-note {
    background: rgba(245, 158, 11, 0.1);
    padding: var(--spacing-lg);
    border-radius: var(--radius-md);
    border-left: 4px solid var(--warning);
}

.important-note p {
    font-size: 1.05rem;
    line-height: 1.8;
    margin: 0;
}

.direct-label {
    background: rgba(16, 185, 129, 0.3) !important;
    color: var(--success) !important;
}

.calculation-explanation {
    background: rgba(59, 130, 246, 0.1);
    padding: var(--spacing-md);
    border-radius: var(--radius-sm);
    margin: var(--spacing-lg) 0;
    text-align: center;
}

.calculation-explanation p {
    margin: 0;
    font-size: 1.1rem;
    color: var(--info);
}

.final-answer {
    background: linear-gradient(135deg, rgba(16, 185, 129, 0.2), rgba(5, 150, 105, 0.2));
    padding: var(--spacing-lg);
    border-radius: var(--radius-md);
    border: 2px solid var(--success);
    margin-top: var(--spacing-xl);
    text-align: center;
    font-size: 1.15rem;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-md);
}

.final-answer i {
    color: var(--success);
    font-size: 1.5rem;
}

/* Responsive para comparaciones */
@media (max-width: 768px) {
    .comparison-diagram {
        flex-direction: column;
    }
    
    .diagram-arrow {
        transform: rotate(90deg);
    }
    
    .step-content {
        padding-left: var(--spacing-sm);
    }
}

.final-summary {
    background: var(--gradient-primary);
    padding: var(--spacing-xl);
    border-radius: var(--radius-lg);
    margin-top: var(--spacing-xl);
}

.final-summary h3 {
    text-align: center;
    margin-bottom: var(--spacing-lg);
    font-size: 1.8rem;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-sm);
}

.summary-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: var(--spacing-md);
}

.summary-card {
    background: rgba(255, 255, 255, 0.1);
    backdrop-filter: blur(10px);
    padding: var(--spacing-lg);
    border-radius: var(--radius-md);
    text-align: center;
    transition: all var(--transition-normal);
}

.summary-card:hover {
    background: rgba(255, 255, 255, 0.15);
    transform: translateY(-5px);
}

.summary-card i {
    font-size: 3rem;
    margin-bottom: var(--spacing-sm);
}

.summary-card h4 {
    margin: var(--spacing-sm) 0;
    font-size: 1.3rem;
}

.summary-card p {
    font-size: 0.95rem;
    margin-bottom: var(--spacing-sm);
}

.summary-card code {
    background: rgba(0, 0, 0, 0.4);
    padding: var(--spacing-sm) var(--spacing-md);
    border-radius: var(--radius-sm);
    font-family: 'Courier New', monospace;
    font-size: 1rem;
    display: block;
    margin-top: var(--spacing-sm);
}

/* ============================================
   RESPONSIVE DESIGN
   ============================================ */
@media (max-width: 768px) {
    .gradient-text {
        font-size: 2.5rem;
    }
    
    .subtitle {
        font-size: 1.4rem;
    }
    
    .welcome-buttons {
        flex-direction: column;
        width: 100%;
    }
    
    .welcome-buttons .btn {
        width: 100%;
    }
    
    .stats-preview {
        flex-direction: column;
        gap: var(--spacing-md);
    }
    
    .tutorial-container {
        grid-template-columns: 1fr;
    }
    
    .tutorial-sidebar {
        position: static;
    }
    
    .mode-grid {
        grid-template-columns: 1fr;
    }
    
    .screen-title {
        font-size: 2rem;
    }
    
    .game-info {
        gap: var(--spacing-md);
    }
    
    .info-value {
        font-size: 1.2rem;
    }
    
    .results-title {
        font-size: 2rem;
    }
    
    .results-animation {
        font-size: 5rem;
    }
    
    .btn-back {
        top: var(--spacing-sm);
        left: var(--spacing-sm);
        padding: 0.5rem 1rem;
        font-size: 0.9rem;
    }
    
    /* Conceptos responsive */
    .visual-proportion {
        flex-direction: column;
    }
    
    .direct-rules, .inverse-rules {
        grid-template-columns: 1fr;
    }
    
    .summary-grid {
        grid-template-columns: 1fr;
    }
    
    .formula-display {
        font-size: 1.3rem;
        padding: var(--spacing-md);
        min-height: 60px;
        flex-wrap: wrap;
    }
    
    .formula-fraction {
        font-size: 1.2rem;
    }
    
    .concept-header h3 {
        font-size: 1.2rem;
    }
    
    .concept-explain {
        font-size: 1rem;
    }
    
    .analysis-table {
        font-size: 0.85rem;
    }
    
    .analysis-table th,
    .analysis-table td {
        padding: var(--spacing-xs);
    }
    
    .compound-step {
        flex-direction: column;
        align-items: flex-start;
    }
    
    .summary-card code {
        font-size: 0.85rem;
    }
}

/* ============================================
   ANIMACIONES ADICIONALES
   ============================================ */
@keyframes shake {
    0%, 100% { transform: translateX(0); }
    25% { transform: translateX(-10px); }
    75% { transform: translateX(10px); }
}

.shake {
    animation: shake 0.5s ease;
}

@keyframes success-pulse {
    0%, 100% {
        transform: scale(1);
        box-shadow: 0 0 0 0 rgba(16, 185, 129, 0.7);
    }
    50% {
        transform: scale(1.05);
        box-shadow: 0 0 0 20px rgba(16, 185, 129, 0);
    }
}

.success-animation {
    animation: success-pulse 0.6s ease;
}

/* ============================================
   UTILIDADES
   ============================================ */
.text-center {
    text-align: center;
}

.mb-1 { margin-bottom: var(--spacing-xs); }
.mb-2 { margin-bottom: var(--spacing-sm); }
.mb-3 { margin-bottom: var(--spacing-md); }
.mb-4 { margin-bottom: var(--spacing-lg); }

.mt-1 { margin-top: var(--spacing-xs); }
.mt-2 { margin-top: var(--spacing-sm); }
.mt-3 { margin-top: var(--spacing-md); }
.mt-4 { margin-top: var(--spacing-lg); }