我如何填补navbar和div之间的差距

Question

这里我是Bootstrap的新手，请帮助我如何消除导航栏和div之间的差距

 [![<nav class="navbar navbar-default">
        <div class="container-fluid">
            <div class="navbar-header">
                <a class="navbar-brand" href="#">
                    <img alt="Brand" src="/show/100-flat-icons-by-graphicloads/home-icon.html">
                </a>
            </div>
        </div>
    </nav>

    <div id="side_Bar">
        <div class="col-sm-4 col-md-4">
            <ul>
                <li>Swiggy</li>
            </ul>
        </div>
    </div>][1]][1]

Answer 1

   .navbar.mb-0 {
    	margin-bottom: 0;
    }
    <nav class="navbar navbar-default mb-0">
        <div class="container-fluid">
           <div class="navbar-header">
               <a class="navbar-brand" href="#">
                  <img alt="Brand" src="/show/100-flat-icons-by-graphicloads/home-icon.html">
                    </a>
            </div>
        </div>
    </nav>
    <div id="side_Bar">
            <div class="col-sm-4 col-md-4">
                <ul>
                    <li>Swiggy</li>
                </ul>
            </div>
        </div>