switching/style/blue.css

nav {
    background-color: #91d8f8;
}

nav > a {
    margin: 10px 0 10px 10px;   /*to collapse margins*/
    border-radius: 5px;
    padding: 10px;
}

nav > a:last-child {
    margin: 10px;               /*to collapse margins*/
}

nav > a:hover,
.button:hover {
    background-color: #bfeaff;
}

nav > a.current,
nav > a.current:hover {
    background-color: #cde6ea;
}

.mainContainer {
    background-color: #f8f8f8;
}

.mainContainer img {
    box-shadow: 2px 3px 6px 2px rgba(0,0,0,0.7);
}

.mainContainer {
    font-size: 16px;
    color: #444;
}

.mainContainer h1 {
    text-align: center;
    font-size: 32px;
    color: inherit;
}

.mainContainer h2 {
    font-size: 28px;
    color: inherit;
}

.mainContainer h3 {
    font-size: 24px;
    color: inherit;
}

.mainContainer h4 {
    font-size: 20px;
    color: inherit;
}