body {
    background-color: #121212;
    color: #e0e0e0;
    font-family: Arial, sans-serif;
    margin: 0;
    padding: 0;
}

header {
    background-color: #1a1a1a;
    padding: 1rem 0;
    border-bottom: 2px solid #ff0000;
}

.header-container {
    width: 90%;
    margin: 0 auto;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

h1 {
    color: #ff0000;
    margin: 0;
}

.btn-volver {
    background-color: #ff0000;
    color: #ffffff;
    padding: 10px 20px;
    text-decoration: none;
    border-radius: 5px;
    font-weight: bold;
    transition: background-color 0.3s ease;
}

.btn-volver:hover {
    background-color: #cc0000;
}

.container {
    display: flex;
    justify-content: space-around;
    padding: 2rem;
    gap: 2rem;
}

.columna {
    background-color: #1e1e1e;
    padding: 1.5rem;
    border-radius: 8px;
    flex: 1;
    border: 1px solid #333;
}

h2 {
    color: #ff0000;
    border-bottom: 1px solid #ff0000;
    padding-bottom: 0.5rem;
}

ul {
    list-style-type: none;
    padding: 0;
}

li {
    background-color: #2a2a2a;
    margin-bottom: 0.5rem;
    padding: 0.75rem;
    border-radius: 4px;
    transition: background-color 0.3s ease;
}

li:hover {
    background-color: #3a3a3a;
}