* {
    box-sizing: border-box;
}

body {
    font-family: Arial, sans-serif;
    background-color: #f0f0f0;
    color: black;
    margin: 0;
    padding: 0;
}

header {
    background-color: #ff0000;
    color: white;
    padding: 20px;
    text-align: center;
    border-bottom: 5px solid black;
}

nav {
    background-color: #333;
    text-align: center;
    padding: 10px;
}

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

nav li {
    display: inline-block;
    margin: 0 10px;
}

nav a {
    color: white;
    text-decoration: none;
    font-weight: bold;
    font-size: 16px;
    padding: 5px;
}

nav a:hover {
    color: #ffff00;
    text-decoration: underline;
}

main {
    width: 90%;
    margin: 20px auto;
    background-color: white;
    padding: 15px;
    border: 1px solid #ccc;
}

h1, h2, h3 {
    color: #ff0000;
    border-bottom: 2px solid #ff0000;
}

img, iframe {
    max-width: 100%;
    height: auto;
    border: 1px solid black;
}

table {
    width: 100%;
    border-collapse: collapse;
    margin-top: 20px;
}

th, td {
    border: 1px solid black;
    padding: 10px;
    text-align: center;
    vertical-align: middle;
}

th {
    background-color: #ccc;
    color: black;
}

td img {
    width: 100px;    
    height: auto;    
    border: 1px solid black;
    display: block;
    margin: 0 auto;
}

tr:nth-child(even) {
    background-color: #eee;
}

tr:hover {
    background-color: #ffcccc;
}

.ganador {
    background-color: #ffd700;
    font-weight: bold;
}

form {
    border: 2px dashed #ff0000;
    padding: 20px;
    background-color: #fff;
    width: 80%;
    margin: 0 auto;
}

fieldset {
    border: 1px solid #000;
    margin-bottom: 15px;
    padding: 10px;
}

legend {
    font-weight: bold;
    background-color: #ff0000;
    color: white;
    padding: 5px;
}

label {
    display: block;
    margin-top: 10px;
    font-weight: bold;
}

input[type="text"],
input[type="email"],
input[type="password"],
input[type="date"],
input[type="tel"],
select,
textarea {
    width: 100%;
    padding: 8px;
    margin-top: 5px;
    border: 2px solid #999;
    background-color: #f9f9f9;
}

textarea {
    resize: none;
    height: 100px;
}

input:focus, 
select:focus, 
textarea:focus {
    outline: none;
    border: 2px solid blue;
    background-color: #e0f7fa;
}

input:hover, 
select:hover, 
textarea:hover {
    background-color: #ddd;
    cursor: text;
}

input[type="submit"],
input[type="reset"] {
    width: 150px;
    padding: 10px;
    margin-top: 20px;
    color: white;
    font-weight: bold;
    border: none;
    cursor: pointer;
}

input[type="submit"] {
    background-color: green;
}

input[type="submit"]:hover {
    background-color: darkgreen;
}

input[type="reset"] {
    background-color: orange;
}

input[type="reset"]:hover {
    background-color: darkorange;
}

footer {
    background-color: black;
    color: white;
    text-align: center;
    padding: 10px;
    margin-top: 20px;
    clear: both;
}

.video-container, .audio-item {
    margin-bottom: 30px;
    padding: 15px;
    border: 1px solid #ccc;
    background-color: #fff;
}

.n-rojo {
    color: red;
    font-weight: bold;
}

.n-amarillo {
    color: #e6b800; 
    font-weight: bold;
}

.n-verde {
    color: green;
    font-weight: bold;
}

.n-azul {
    color: blue;
    font-weight: bold;
}