// Extra small devices (portrait phones, less than 576px)
@media (max-width: 575px) { ... }
// Small devices (landscape phones, 576px and up)
@media (min-width: 576px) and (max-width: 767px) { ... }
// Medium devices (tablets, 768px and up)
@media (min-width: 768px) and (max-width: 991px) { ... }
// Large devices (desktops, 992px and up)
@media (min-width: 992px) and (max-width: 1199px) { ... }
// Extra large devices (large desktops, 1200px and up)
@media (min-width: 1200px) { ... }
當程式碼如以下指定，代表我們希望這些元件在不同螢幕大小時有不一樣的表現
<!-- Stack the columns on mobile by making one full-width and the other half-width -->
<div class="row">
<div class="col-12 col-md-8">.col-12 .col-md-8</div>
<div class="col-6 col-md-4">.col-6 .col-md-4</div>
</div>
<!-- Columns start at 50% wide on mobile and bump up to 33.3% wide on desktop -->
<div class="row">
<div class="col-6 col-md-4">.col-6 .col-md-4</div>
<div class="col-6 col-md-4">.col-6 .col-md-4</div>
<div class="col-6 col-md-4">.col-6 .col-md-4</div>
</div>
<!-- Columns are always 50% wide, on mobile and desktop -->
<div class="row">
<div class="col-6">.col-6</div>
<div class="col-6">.col-6</div>
</div>
