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

/* Fuente general */
body {
    font-family: 'Segoe UI', Tahoma, sans-serif;
    background: #f4f6f9;
    color: #333;
}

/* HEADER */
header {
    background: linear-gradient(135deg, #4facfe, #00f2fe);
    color: white;
    text-align: center;
    padding: 20px;
}

/* NAV */
nav {
    background: #222;
    color: white;
    text-align: center;
    padding: 10px;
}

/* CONTENEDOR PRINCIPAL */
main {
    display: grid;
    grid-template-columns: 3fr 1fr;
    gap: 20px;
    padding: 20px;
}

/* SECTION */
section {
    background: white;
    border-radius: 10px;
    padding: 20px;
    box-shadow: 0px 4px 10px rgba(0,0,0,0.1);
}

/* BOTONES */
button {
    background: #4facfe;
    color: white;
    border: none;
    padding: 10px 15px;
    margin: 5px;
    border-radius: 8px;
    cursor: pointer;
    transition: 0.3s;
}

button:hover {
    background: #007bff;
    transform: scale(1.05);
}

/* INPUT */
input {
    padding: 10px;
    margin-top: 10px;
    width: 100%;
    border-radius: 8px;
    border: 1px solid #ccc;
}

/* CAJA */
.caja {
    width: 200px;
    height: 100px;
    background: #4facfe;
    color: white;
    display: flex;
    align-items: center;
    justify-content: center;
    margin-top: 15px;
    border-radius: 10px;
    transition: all 0.5s;
}

/* LISTA */
ul {
    margin-top: 15px;
    padding-left: 20px;
}

li {
    margin: 5px 0;
}

/* ARTICLE */
article {
    margin-top: 20px;
    background: #fff;
    padding: 15px;
    border-radius: 10px;
    box-shadow: 0px 2px 6px rgba(0,0,0,0.1);
}

/* ASIDE */
aside {
    background: #ffffff;
    padding: 20px;
    border-radius: 10px;
    height: fit-content;
    box-shadow: 0px 4px 10px rgba(0,0,0,0.1);
}

/* FOOTER */
footer {
    background: #222;
    color: white;
    text-align: center;
    padding: 15px;
    margin-top: 20px;
}

/* CLASE OCULTO */
.oculto {
    display: none;
}

/* RESPONSIVE */
@media (max-width: 768px) {
    main {
        grid-template-columns: 1fr;
    }
}