* {
    box-sizing: border-box !important;
}

body {
    font-family: Arial, sans-serif;
    margin: 20px;
    background-color: #ccc;
}

header{
    width: 100%;
    background-color: #999;
}

.imagenes img {    
    width: 13%;
    float: right;
    margin: 2%;
    margin-top: 1%;
}

p {
    line-height: 1.6;
}

h1{
    text-align: center;
    color: black;
    padding: 1%;
    margin: 5%;
}

h2{
    text-decoration: underline;
}

ul {
    margin-bottom: 1.2em;
}