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

:root {
    --color-fondo: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    --color-correcto: #2ecc71;
    --color-incorrecto: #e74c3c;
    --color-texto: #2d3436;
    --sombra-fuerte: 0 15px 35px rgba(0,0,0,0.2);
}

body { 
    font-family: 'Poppins', sans-serif; 
    background: var(--color-fondo);
    color: var(--color-texto);
    display: flex;
    justify-content: center;
    align-items: flex-start; 
    min-height: 100vh;
    padding: 40px 20px; 
}

.contenedor { 
    width: 100%;
    max-width: 700px; 
    margin: 0 auto; 
    background: #ffffff; 
    padding: 40px; 
    border-radius: 25px; 
    box-shadow: var(--sombra-fuerte);
    text-align: center;
    position: relative;
}

h1 {
    color: #4834d4;
    font-weight: 800;
    margin-bottom: 10px;
}

.barra-progreso-fondo {
    height: 8px;
    background-color: #dfe6e9;
    border-radius: 10px;
    margin-bottom: 25px;
    overflow: hidden;
}

#barra-progreso-relleno {
    height: 100%;
    background-color: #0984e3;
    width: 0%;
    transition: width 0.5s ease-in-out;
}

.info-estado {
    display: flex;
    justify-content: space-between;
    margin-bottom: 30px;
    font-weight: 600;
    color: #636e72;
    font-size: 1.1rem;
}

#pregunta {
    font-size: 1.3rem;
    margin-bottom: 20px;
    color: #2d3436;
    font-weight: 600;
    line-height: 1.4;
}

#zona-reaccion {
    height: 70px; 
    display: flex;
    justify-content: center;
    align-items: center;
    font-size: 3.5rem; 
    margin-bottom: 15px;
}

.animacion-rebote {
    animation: rebote 0.6s cubic-bezier(0.68, -0.55, 0.265, 1.55);
}

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

.contenedor-botones { 
    display: flex; 
    flex-direction: column; 
    gap: 15px; 
}

.boton { 
    background-color: #f1f2f6; 
    border: none;
    border-radius: 15px; 
    padding: 15px 20px; 
    font-size: 1rem; 
    font-family: inherit;
    font-weight: 600;
    cursor: pointer; 
    transition: all 0.2s; 
    color: #2d3436;
    box-shadow: 0 5px 15px rgba(0,0,0,0.05);
    position: relative;
    overflow: hidden;
}

.boton:hover:not(:disabled) { 
    background-color: #dfe6e9;
    transform: translateY(-3px);
    box-shadow: 0 8px 20px rgba(0,0,0,0.1);
}

.boton:active:not(:disabled) {
    transform: translateY(-1px);
}

.boton.correcto { 
    background-color: var(--color-correcto) !important; 
    color: white; 
    box-shadow: 0 0 20px rgba(46, 204, 113, 0.6) !important;
    transform: scale(1.02);
}

.boton.incorrecto { 
    background-color: var(--color-incorrecto) !important; 
    color: white; 
    opacity: 0.8;
}

.boton:disabled {
    cursor: default;
}

#contenedor-retroalimentacion {
    margin-top: 25px;
    padding: 20px;
    border-radius: 15px;
    text-align: left;
    animation: aparecer 0.5s ease-out;
}

#contenedor-retroalimentacion.acierto {
    background-color: rgba(46, 204, 113, 0.1);
    border-left: 5px solid var(--color-correcto);
}

#contenedor-retroalimentacion.fallo {
    background-color: rgba(231, 76, 60, 0.1);
    border-left: 5px solid var(--color-incorrecto);
}

#titulo-retroalimentacion {
    margin: 0 0 10px 0;
    font-size: 1.2rem;
}

#contenedor-retroalimentacion.acierto #titulo-retroalimentacion { color: #27ae60; }
#contenedor-retroalimentacion.fallo #titulo-retroalimentacion { color: #c0392b; }

#texto-retroalimentacion {
    margin: 0;
    font-size: 1rem;
    color: #34495e;
}

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

#boton-siguiente { 
    margin-top: 30px;
    background: linear-gradient(to right, #4834d4, #686de0);
    color: white;
    border: none;
    padding: 15px 40px;
    font-size: 1.2rem;
    border-radius: 50px;
    cursor: pointer;
    transition: all 0.3s ease;
    font-weight: 800;
    box-shadow: 0 10px 20px rgba(72, 52, 212, 0.3);
}

#boton-siguiente:hover {
    transform: translateY(-5px);
    box-shadow: 0 15px 25px rgba(72, 52, 212, 0.5);
}

.oculto { display: none !important; }