body {
    margin: 0;
    padding: 0;
    font-family: "Hiragino Kaku Gothic Pro", "ヒラギノ角ゴ Pro W3", メイリオ, Meiryo, "ＭＳ Ｐゴシック", "Helvetica Neue", Helvetica, Arial, sans-serif;
    background-color: #b8b8b8;
 }
 
 header {
    padding: 30px 4% 10px;
    position: fixed;
    top: 0;
    width: 100%;
    background-color: #fff;
    display: flex;
    align-items: center;
 }

 h1 {
    margin: 0;
    padding: 0;
    font-size: 20px;
 }
 
 a {
    text-decoration: none;
    color: #4b4b4b;
 }
 
 ul {
    list-style: none;
    margin: 0;
    display: flex;
 }
 
 li {
    margin: 0 0 0 15px;
    font-size: 14px;
 }
 
 nav {
    margin: 0 0 0 0;
 }
 
 main {
    padding: 100px;
    font-size: 15px;
 }
 
 footer {
    text-decoration: none;
    background-color: #fff;
    text-align: center

}