html {
    background-color: white;
    
}
.page-header {
    background-color: #222222;
    color: #FFFFFF;
    padding: 20px;
    text-align:center;
  }
  .introduction {
    background-color: #222222;
    padding: 30px;
    width: 700px;
    margin: 0 auto;
    margin-top: 30px;

    color: #FFFFFF;
    font-size: 14px;
    line-height: 130%;
}
.page-footer {
    background-color: #222222;
    color: #FFFFFF;
    padding: 20px;
    margin-top:30px;
    text-align:center;
}
.gallery {
    background-color: #222222;
    color: #FFFFFF;
    padding: 30px;
    width: 700px;
    margin: 0 auto;
    margin-top: 30px;
    text-align:center;
}
.gallery img {
    height: 100px;
    border-width: 5px;
    border-color: #FFFFFF;
    border-style: solid;
    box-shadow: 3px 3px 5px 6px #000000;
    margin: 5px;
}
.videos {
    background-color: #222222;
    color: #FFFFFF;
    padding: 30px;
    width: 700px;
    margin: 0 auto;
    margin-top: 30px;
    text-align:center;
}
.main-menu {
    background: black;
}
.main-menu a {
    background-color: black;
    border-color: white;
    font-weight: bold;
    display: inline-block;
    padding: 5px 10px;
}

.main-menu a:hover {
    background-color:black;
    color: white;
}