設定按鈕 （.btn-*）

• 按鈕類可用於<a>,<button>,<input>元素上 

<a href="#" class="btn btn-info" role="button">連結按鈕</a>
<button type="button" class="btn btn-info">按鈕</button>
<input type="button" class="btn btn-info" value="輸入框按鈕">
<input type="submit" class="btn btn-info" value="提交按鈕">
 

<button type="button" class="btn">基本按鈕</button>
<button type="button" class="btn btn-primary">主要按鈕</button>
<button type="button" class="btn btn-secondary">次要按鈕</button>
<button type="button" class="btn btn-success">成功</button>
<button type="button" class="btn btn-info">訊息</button>
<button type="button" class="btn btn-warning">警告</button>
<button type="button" class="btn btn-danger">危險</button>
<button type="button" class="btn btn-dark">黑色</button>
<button type="button" class="btn btn-light">淺色</button>
<button type="button" class="btn btn-btn-link">連結</button>
 

按鈕設定邊框（.btn-outline-*）

<button type="button" class="btn btn-outline-primary">主要按鈕</button>
<button type="button" class="btn btn-outline-secondary">次要按鈕</button>
<button type="button" class="btn btn-outline-success">成功</button>
<button type="button" class="btn btn-outline-info">訊息</button>
<button type="button" class="btn btn-outline-warning>警告</button>
<button type="button" class="btn btn-outline-danger">危險</button>
<button type="button" class="btn btn-outline-dark">黑色</button>
<button type="button" class="btn btn-outline-light">淺色</button>
 

按鈕設定大小（.btn-lg/.btn-sm）

<button type="button" class="btn btn-primary btn-lg">大號按鈕</button>
<button type="button" class="btn btn-primary">預設按鈕</button>
<button type="button" class="btn btn-primary btn-sm">小號按鈕</button> 

塊級按鈕（.btn-block）

<button type="button" class="btn btn-primary btn-block">按鈕</button>

按鈕的啟用與禁用（.active/.disabled）