* {
    margin: 0;
    padding: 0;
    list-style: none;
    background-color: #F0F8FF;
}

#layout {
    display: flex;
    width: 80%;
    margin: 0 auto;
    flex-direction: column;
}

#top {
    width: 100%;
    flex: 0 0 30px;
    background-color: aqua;
}

#main {
    flex: 0 0 100%;
    display: flex;
    margin-top: 30px;
}

#main div:first-child {
    flex: 0 0 10%;
    background-color: #F0F8FF;
    flex-wrap: wrap;
    display: flex;
    border: 1px solid #00FA9A;
}

#main div:first-child li {
    flex: 0 0 100%;
    height: 40px;
    line-height: 40px;
    text-align: center;
    border-bottom: 1px solid #00FA9A;
}

#main div:nth-child(2) {
    flex: 0 0 90%;
    background-color: #F0F8FF;
    flex-wrap: wrap;
    display: flex;
    border: 1px solid #00FA9A;
    justify-content: space-around;
}

#main div:nth-child(2) li {
    flex: 0 0 22%;
    height: 100px;
    background-color: #87CEEB;
    margin-top: 10px;
}