/* reset CSS */
* {
    margin: 0;
    padding: 0;
}

ul {
    list-style: none;
}

a {
    text-decoration: none;
}

#wrap {
    width: 80%;
    margin: 0 auto;
    padding-top: 10px;
}

/* 1depth Menu */
ul.main_menu li {
    height: 48px;
    line-height: 48px;
}

ul.main_menu>li {
    float: left;
    width: 25%;
    text-align: center;
}

ul.main_menu>li>a {
    display: block;
    height: inherit;
    border: 1px solid lightgray;
    color: #333;
    border-radius: 20px 20px 0 0;
}

ul.main_menu>li:hover>a {
    color: #a0a;
    background-color: pink;
}

ul.main_menu>li>a::after {
    content: ' ▼';
}

/* 2depth Menu */
ul.sub_menu {
    display: none;
    border: 1px solid lightgray
}

ul.sub_menu>li a {
    display: block;
    color: #333;
    background-color: lightcyan;
}

ul.sub_menu>li a:hover {
    color: #a0a;
    background-color: pink;
}