body{
    max-width: 1200px;
    margin: auto;
    background-color: #dde5dd;
}
/* 問題1 */
ul{margin-left: 60px;}
li{list-style-image:url("aaa.png");}
li:hover{list-style-image:url("bbb.png") ;}
li:active{list-style-image:url("ccc.png") ;}

/* 問題2 */
.container {
    margin: 0 auto;
    padding: 20px;
}

table {
    width: 100%;
    border-collapse: collapse;
    margin-bottom: 20px;
    background-color: #fff;
}

caption{
    font-size: 40px;
    font-weight: bold;
    margin-bottom: 30px;
}
th, td {
    padding: 10px;
    text-align: left;
    vertical-align: middle;
    border: 2px solid #ddd;
}

th {
    background: #8cd58f;
}

input[type="button"] {
    font-size: 20px;
    margin-bottom: 5px;
}

.btn {
    display: block;
    width: 100px;
    margin: 0 auto;
    padding: 10px;
    background-color: #4caf50;
    color: #fff;
    border: none;
    cursor: pointer;
}

.btn:hover{
    background-color: #459f48;
}

.result {
    text-align: center;
    font-weight: bold;
    margin-top: 20px;
}