* {
    margin: 0;
    padding: 0;
}

body {
    position: relative;
    background-color: #f5f5f5; 
    font-family: 'Trebuchet MS', Arial, sans-serif;
    color: #181818;
}
header {
    background: url('../img/banner.jpg');
    background-size: cover; 
    background-position: center;
    background-color: white;
    background-repeat: no-repeat;
    height: 300px; 
    width: 100%;   
    position: relative;
}

#titulo {
    display: block;
    padding: 20px;
}

#logo {
    display: inline-block;
    height: 100px;
    width: auto;
    margin-right: 20px;
    vertical-align: middle;
}

header h1 {
    
    display: inline-block;
    margin-bottom: 0;
    vertical-align: middle;
    color: #1a1a1a;
    text-shadow: 0 0 17px white;
    font-size: 2em;
    
}

nav {
    width: 100%;
    height: 40px;
    text-align: right;
    background-color: #1a1a1a;
    position: absolute;
    bottom: 0;
    box-sizing: border-box;
}

nav ul {
    list-style-type: none;
    padding-right: 15px;
}

nav li {
    display: inline-block;
    margin-left: 15px;
}

nav a {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    font-size: 1.3em;
    color: #ebebeb;
    text-decoration: none;
    line-height: 40px;
}

nav a:hover {
    color: #FF6600;
    border-bottom: 3px solid #FF6600;
}
img {
    height: 250px;
    max-width: 100%;
    border-radius: 8px; 
    display: block;      
    margin: 10px auto;  
}

section img {
    height: 200px;     
    width: auto;        
    margin: 15px 5px;  
    display: inline-block; 
    vertical-align: top;
}


section div {
    text-align: center; 
    margin: 20px 0;     
}

article {
    padding: 10px;
    overflow: hidden;
    text-align: justify;
}

section {
    padding: 10px;
    float: left;
    width: 75%;
    box-sizing: border-box;
    text-align: justify;
}

aside {
    padding: 10px;
    float: right;
    width: 23%;
    border: 2px solid #FF6600;
    box-sizing: border-box;
    border-radius: 8px; 
}

#alumnoperfil {
    background-color: #FF6600;
    padding: 10px;
    text-align: center;
    margin-bottom: 10px;
    border-radius: 6px;  
}

#alumnoperfil img {
    height: auto;
    width: 150px;
    border-radius: 6px; 
}

footer {
    clear: both;
    width: 100%;
    height: auto;
    padding: 20px 0;
    box-sizing: border-box;
    border-top: 2px solid #FF6600;
    background-color: #1a1a1a;
    color: white;
    text-align: center;
}