/* --- Variables de Color (Continuidad) --- */
:root {
    --color-background-soft: #F5F5F5; /* Fondo gris claro */
    --color-background-card: #FFFFFF;
    --color-text-dark: #1C1C1E;
    --color-text-mid: #5A5A5A;
    --color-accent-blue: #4A90E2; /* Azul Vibrante */
    --color-light-blue: #EAF3FF; /* Fondo de icono principal */
    --color-border-card: #E0E0E0; 
    --color-primary-button: #1C1C1E; /* Botón Negro */
    --color-secondary-button-text: #FFFFFF; /* Texto Blanco para botón principal */
    --font-primary: 'Helvetica Neue', Arial, sans-serif;
}

/*====================================================================
  1. ESTILOS BASE Y CONTENEDOR PRINCIPAL (CENTRADOS)
======================================================================*/
body {
    background-color: var(--color-background-soft);
    font-family: var(--font-primary);
}

main {
    max-width: 1200px;
    margin: 0 auto;
    padding: 60px 20px;
}

main {
    flex-grow: 1; 
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center; /* Centrado vertical */
    text-align: center;
    padding: 60px 20px;
}

/* --- Imagen de Error (404.png) --- */
main > img:first-child {
    width: auto;
    margin-bottom: 25px;
    
    /* Si 404.png es un número o icono que necesita fondo */
    padding: 15px;
    border-radius: 12px;
}

/* --- Título H1 --- */
main h1 {
    font-size: clamp(2rem, 5vw, 2.8rem);
    font-weight: 800;
    color: var(--color-text-dark);
    margin-bottom: 15px;
    line-height: 1.2;
}

/* --- Párrafo Descriptivo --- */
main p {
    font-size: 1.05em;
    color: var(--color-text-mid);
    max-width: 500px;
    margin: 0 auto 30px;
}

/* --- Contenedor de Botones --- */
.button {
    display: flex;
    justify-content: center;
    margin-top: 10px;
}

/* --- Botón Único: Volver al inicio --- */
.button a {
    display: inline-flex;
    align-items: center;
    padding: 14px 28px;
    text-decoration: none;
    font-weight: 600;
    border-radius: 4px;
    font-size: 1em;
    transition: background-color 0.3s, box-shadow 0.3s;
    
    /* Estilo del Botón Primario (Negro) */
    background-color: var(--color-primary-button);
    color: var(--color-secondary-button-text);
    border: 1px solid var(--color-primary-button);
}

.button a:hover {
    background-color: #333;
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.1);
}

/* --- Responsive --- */
@media (max-width: 500px) {
    main {
        padding: 40px 15px;
    }
    
    main > img:first-child {
        height: 80px;
    }
    
    main h1 {
        font-size: 2rem;
    }

    .button a {
        width: 100%;
        max-width: 300px;
        justify-content: center;
    }
}