字型大小使用 em, rem 作為單位，然後使用 media query 來調整 html 元素的 font-size

自適應網站

html {font-size: 62.5%!important; /* 10÷16=62.5% */}
@media only screen and (min-width: 481px){
    html {
        font-size: 94%!important; /* 15.04÷16=94% */
    }
}
@media only screen and (min-width: 561px){
    html {
        font-size: 109%!important; /* 17.44÷16=109% */
    }
}
@media only screen and (min-width: 641px){
    html {
        font-size: 125%!important; /* 20÷16=125% */
    }
}
 

@media only screen and (min-width: 320px){html {font-size: 62.5%!important;}}
@media only screen and (min-width: 360px){html {font-size: 72.5%!important;}}
@media only screen and (min-width: 400px){html {font-size: 82.5%!important;}}
@media only screen and (min-width: 480px){html {font-size: 94%!important;}}