1.確保邊框邊距包含在元素的寬度和高度間

*{
        box-sizing:border-box;
    }

2.基本模板

.col-1 {width: 8.33%;}
.col-2 {width: 16.66%;}
.col-3 {width: 25%;}
.col-4 {width: 33.33%;}
.col-5 {width: 41.66%;}
.col-6 {width: 50%;}
.col-7 {width: 58.33%;}
.col-8 {width: 66.66%;}
.col-9 {width: 75%;}
.col-10 {width: 83.33
 
%;}
.col-11 {width: 91.66%;}
.col-12 {width: 100%;}

<div class="row">
    <div class="col-3"></div>
    <div class="col-6"></div>
    <div class="col-3"></div>
</div>

3.對擁有寬度設定的div，配置屬性

[class*="col-"] {
    float:left;
}
.row:after {
    content: "";
    clear
 
: both;
    display: block;
}

4.但上述給col設定百分比，在移動裝置上無效，可做如下設定

@media only screen and (max-width: 768px) {
    /* For mobile phones: */
    [class*="col-"] {
        width: 100%;
    }
}

/* 為移動端設計: */
[class*="col-"] {
    width: 100%;
}
@media only screen and (min-width: 768px) {
    /* For desktop: */
    .col-1
 
 {width: 8.33%;}
    .col-2 {width: 16.66%;}
    .col-3 {width: 25%;}
    .col-4 {width: 33.33%;}
    .col-5 {width: 41.66%;}
    .col-6 {width: 50%;}
    .col-7 {width: 58.33%;}
    .col-8 {width: 66.66%;}
    .col-9 {width: 75%;}
    .col-10 {width: 83.33%;}
    .col-11 {width: 91.66%;}
    .col-12 {width: 100%;}
}

5.橫屏豎屏設定

@media only screen and (orientation: landscape){}
@media only screen and (orientation: portrait){}