CSS浮动行为神秘

Question

我使用Bootstrap 3来创建一个移动响应网站。 我的网页上有两个顶级菜单。顶部菜单有一个ul浮动到右侧，下面的菜单有两个组件：一个ul向左浮动并且搜索框向右浮动。 尽管float：right正在搜索框上工作，但它并没有移动到极端的正确位置;而是从右侧留下一些空间。我没有在搜索框中应用任何右边距。

但是，当我从顶层菜单的ul（.settings-menu ul）中删除浮动时，搜索框会移至最右端。这两个菜单位于不同的div中。我不明白为什么会发生这种情况。有人能解释为什么会发生这种情况并推荐解决方案？我的代码如下：

<div class="settings-menu"> <!-- Top settings/registration panel --> 
    <ul> 
     <li><a>Register</a></li> 
     <li><a>LogIn</a></li> 
     <li><a>Wishlist(0)</a></li> 
     <li><a>My Account</a></li> 
    </ul> 
</div> 

<nav class="navbar"> 

    <div class="navbar-header"> 
     <button type="button" class="navbar-toggle" data-toggle="collapse" data-target="#menu-collapse"> 
      <span class="sr-only">Toggle navigation</span> 
      <span class="icon-bar"></span> 
      <span class="icon-bar"></span> 
      <span class="icon-bar"></span> 
     </button> 
    </div> 

    <div class="collapse navbar-collapse" id="menu-collapse"> 
     <ul class="nav navbar-nav"> 
     <li><a href="#">Home Page</a></li> 
     <li><a href="#">Shop by category</a></li> 
     <li><a href="#">Designers</a></li> 
     <li><a href="#">Blog</a></li> 
     <li><a href="#">Contact Us</a></li> 
     </ul> 

     <form class="navbar-form" role="search"> 
     <label for="id_search"></label> 
     <input type="text" id="id_search" class="form-control" name="search_item" placeholder="Search Store"> 
     <button type="submit" name="search_button" id="id_search_button" class="search-button"></button> 
     </form> 
    </div><!-- /.navbar-collapse --> 

</nav> 

CSS：

body { 
    font-family: arial; 
    font-size: 12px; 
    background: url("images/texture_2.jpg") 
} 

.settings-menu { 
    background-color: #E87772; 
    border-bottom: 4px solid #F1ADAA; 
    height: 36px; 
} 

.settings-menu ul { 
    float: right; 
    width: auto; 
    margin-right: 5%; 
} 

.settings-menu ul li{ 
    display: inline-block; 
    padding: 5px; 
    list-style: none; 
} 

.settings-menu ul li a{ 
    color: #fff; 
    font-size: 14px; 
} 

nav { 
    background-color: #fff; 
    width: 100%; 
} 

nav ul { 
    float: left; 
} 

.navbar-nav > li {  /*over-riding bootstrap's classes */ 
    display: inline-block; 
    padding: 7px; 
    margin-right: 7px; 
} 

.navbar-nav > li > a{ 
    font-size: 16px; 
    color: rgb(80,80,80); 
    padding: 0px; 
    padding-bottom: 7px; 
} 

.navbar-nav > li > a:hover{ 
    background-color: #fff; 
} 

.navbar-nav > li > a:after{ 
    background: none repeat scroll 0 0 #e87772; 
    bottom: 0; 
    content: " "; 
    height: 2px; 
    left: 50%; 
    position: absolute; 
    transition: all 0.25s ease-in-out 0s; 
    width: 0; 
} 

.navbar-nav > li > a:hover:after, .navbar-nav > li > a:focus:after { 
    left: 0; 
    width: 100%; 
}  

.navbar-form { 
    float: right; 
    display: inline-block; 
    margin-top: 0; 
    width: 285px; 
    height: 45px; 
} 

.navbar-form .search-button { 
    background: url("images/icon-search-button.png") no-repeat; 
    border-radius: 100%; 
    background-color: #E87772; 
    height: 38px; 
    width: 38px; 
    background-position: center; 
    border: none; 
    transition-property: height, width; 
    transition-duration: 50ms; 
    transition-timing-function: ease-in-out; 
} 


.navbar-form .search-button:hover { 
    height: 40px; 
    width: 40px;  
} 

.navbar-form .cart-button { 
    background: url("images/icon-cart-link.png") no-repeat; 
    border-radius: 100%; 
    background-color: #E87772; 
    height: 38px; 
    width: 38px; 
    background-position: center; 
    border: none; 
    transition-property: height, width; 
    transition-duration: 50ms; 
    transition-timing-function: ease-in-out; 
} 

.navbar-form .cart-button:hover { 
    height: 40px; 
    width: 40px;  
} 


#id_search {    /* for text-box */ 
    border-radius: 0px; 
    border-right: none; 
    border-left: none; 
    border-top: 1px solid #DDDDDD; 
    border-bottom: 1px solid #DDDDDD; 
    box-shadow: none; 
    margin-top: 5px; 
} 

#search-box { 
    float: right; 
} 

Answer 1

.navbar-collapse.collapse有由bootstrape默认填充。尝试在.navbar崩溃这个Demo

.navbar-collapse.collapse{ 
    padding-right :0 !important; 
}