:root {
    --blanco: #ffffff;
    --negro: #000000;
}

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

body {
    font-family: 'Arial', sans-serif;
    line-height: 1.6;
    background-color: var(--blanco);
    color: var(--negro);
}

.container {
    max-width: 800px;
    margin: 0 auto;
    padding: 20px;
}

header {
    text-align: center;
    margin-bottom: 2rem;
}

.categories {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 1rem;
    margin: 2rem 0;
}

.category {
    padding: 1rem;
    border: 2px solid var(--negro);
    text-align: center;
    cursor: pointer;
    transition: all 0.3s ease;
}

.category:hover {
    background-color: var(--negro);
    color: var(--blanco);
}

.question {
    margin: 1.5rem 0;
    padding: 1rem;
    border-bottom: 1px solid #ccc;
}

.result-icon {
    margin-left: 1rem;
    font-weight: bold;
}

#timer {
    position: fixed;
    top: 20px;
    right: 20px;
    font-size: 1.5rem;
    font-weight: bold;
}

.modal {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0,0,0,0.5);
    justify-content: center;
    align-items: center;
}

.modal-content {
    background: var(--blanco);
    padding: 2rem;
    text-align: center;
}

.hidden {
    display: none;
}

/* Estilos adicionales para tabs, formularios y puntajes */