.giga{
    background-color:#f1f1f1;
}
.giga img{
    width:100%;
}
.giga_bg_gray{
    background-color:#f1f1f1;
}
.giga_bg_white{
    padding-bottom: 30px;
}
.giga_case{
    display: flex;
    flex-wrap: wrap;
    padding: 0 20px;
    justify-content: space-between;
    background-color:#fff;
}
.giga_case a{
    width: 48%;
    margin: 0 0 30px;
    text-decoration:none;
}
.giga_case a button{
    display: block;
    width: 80%;
    margin: 0 auto;
    background-color:#fff;
    border: 0.5px solid;
    border-radius: 20px;
    padding: 5px 0;
    font-size: 12px;
    color:#333;
    text-decoration: none;
}
.giga_case a button:hover{
    background-color:#f2f2f2;
    cursor: pointer;
}
.giga_footer{
    padding: 0 0 100px;
}
@media screen and (min-width:768px){
    .giga_bg_gray{
        max-width: 550px;
        margin: 0 auto;
    }
    .giga_bg_gray a{
        display: block;
        max-width: 450px;
        margin: 0 auto;
    }
    .giga_bg_gray img#rank{
        max-width: 800px;
    }
    .giga_bg_white{
        max-width: 500px;
        margin: 0 auto;
        padding-bottom: 50px;
    }
    .giga_footer{
        max-width: 450px;
        margin: 0 auto;
    }
    .giga_case a{
        margin: 0 0 50px;
    }
    .giga_case a button{
        font-size: 16px;
    }
}