title: Input Fields Are Too Wide
body: <p>I am designing a responsive web page which contains a form.
  But all the input elements are getting out of the form from left and right.
  Can anyone tell me, What is the reason behind this.?</p>
  
  <p><strong>My Demo Code ...</strong></p>
  
  <pre><code>&lt;!DOCTYPE html&gt;
  &lt;html lang="en"&gt;
  &lt;head&gt;
      &lt;meta charset="UTF-8"&gt;
      &lt;title&gt;Temp Pages for Testing &lt;/title&gt;
      &lt;meta charset="UTF-8"&gt;
      &lt;meta name="viewport" content="width=device-width, initial-scale=1"&gt;
      &lt;link rel="stylesheet" href="./css/bootstrap.css"&gt;        
      &lt;style&gt;
          .custFrmOnlyBkCol { background-color: lightgray;    }
      &lt;/style&gt;
  &lt;/head&gt;
  
  &lt;body&gt;
      &lt;div class="jumbotron"&gt;
          &lt;div class="col-md-12"&gt;
              &lt;form action="#" class="custFrmOnlyBkCol"&gt;
                  &lt;!--        In Css :  .custFrmOnlyBkCol { background-color: lightgray;    }     --&gt;
                  &lt;div class="form-group row"&gt;
                      &lt;label class="col-3 text-right"&gt;Id&lt;/label&gt;
                      &lt;div&gt;
                          &lt;p&gt;101&lt;/p&gt;
                      &lt;/div&gt;
                  &lt;/div&gt;
                  &lt;div class="form-group row"&gt;
                      &lt;label class="col-3 text-right" for=""&gt;First Name&lt;/label&gt;
                      &lt;input type="text" class="form-control col-md-9"&gt;
                  &lt;/div&gt;
                  &lt;div class="form-group row"&gt;
                      &lt;label class="col-3 text-right" for=""&gt;Last Name&lt;/label&gt;
                      &lt;input type="text" class="form-control col-md-9"&gt;
                  &lt;/div&gt;
                  &lt;input class="form-control offset-md-3 col-md-6 btn btn-primary" type="submit" value="Submit"&gt;
              &lt;/form&gt;
          &lt;/div&gt;
      &lt;/div&gt;
  &lt;/body&gt;
  
  &lt;/html&gt;
  </code></pre>
  
  <p><a href="https://i.stack.imgur.com/zXUNm.jpg" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/zXUNm.jpg" alt="enter image description here"></a></p>