.head {
    width: 100%;
    height: 70px;
    position: fixed;
    top: 0;
    left: 0;
    background-color: #E1E1E1;
    box-shadow: 0 3px 3px rgba(0, 0, 0, 0.3);
    z-index: 0;
}

.head .center {
    margin: 0 auto;
    max-width: 1280px;
    height: 100%;
    display: flex;
    justify-content: space-between;
}

.head .center .left {
    width: 200px;
    height: 100%;
    background-color: blue;
}

.head .center .right {
    height: 100%;
}