左側固定，右側自適應的佈局方式(新增評論區大佬教的方法）

一.浮動佈局

1.先讓固定寬度的div浮動！使其脫離文檔流。
2.margin-left的值等於固定div的寬度相等。

.aside{
        float: left;
        width: 200px;
        background-color: red;
    }
    .content{
        margin-left: 200px;
        background-color: blue;
    }
    
<div class="aside">
    Lorem ipsum dolor sit amet, consectetur adipisicing elit. Labore provident dolor in voluptatum tempore non, placeat obcaecati totam ut delectus libero excepturi distinctio asperiores odit nobis soluta, esse aspernatur beatae.
</div>
<div class="content">
    Lorem ipsum dolor sit amet, consectetur adipisicing elit. Labore provident dolor in voluptatum tempore non, placeat obcaecati totam ut delectus libero excepturi distinctio asperiores odit nobis soluta, esse aspernatur beatae.
</div>

二.margin的負值(3個div)

1. 是固定寬度的div脫離文檔流。
2. 利用marin負值可使得，後面的div能夠與前面的div 保持同行顯示。

3. 給包裹內容的div加margin-left 可使得與左邊的文字不重疊

   .aside{
       float: left;
       margin-right: -200px;
       width: 200px;
       background-color: red;
   }
   .content{
       float: right;
   }
   .content .inner{
       margin-left: 200px;
       background-color: blue;
   }
   
    <div class="aside">
      Lorem ipsum dolor sit amet, consectetur adipisicing elit. Labore provident dolor in voluptatum tempore non, placeat obcaecati totam ut delectus libero excepturi distinctio asperiores odit nobis soluta, esse aspernatur beatae.
   </div>
   <div class="content">
      <div class="inner">
         Lorem ipsum dolor sit amet, consectetur adipisicing elit. Labore provident dolor in voluptatum tempore non, placeat obcaecati totam ut delectus libero excepturi distinctio asperiores odit nobis soluta, esse aspernatur beatae.
      </div>

   </div>

三.calc()計算屬性

注意：使用calc計算屬性的時候 運算符(- +等等)兩邊必須有空格

1. 注意兩個div必須一左一右浮動。

2. calc的寬度必需要減去的寬度要與固定寬度保持一致。

   .aside{
         float: left;
         width: 200px;
         background-color: red;
     }
     .content{
         calc:(100% - 200px);
         background-color: blue;
     }

   <div class="aside">

   Lorem ipsum dolor sit amet, consectetur adipisicing elit. Labore provident dolor in voluptatum tempore non, placeat obcaecati totam ut delectus libero excepturi distinctio asperiores odit nobis soluta, esse aspernatur beatae.
      </div>
    <div class="content">
        Lorem ipsum dolor sit amet, consectetur adipisicing elit. Labore provident dolor in voluptatum tempore non, placeat obcaecati totam ut delectus libero excepturi distinctio asperiores odit nobis soluta, esse aspernatur beatae.        
     </div>

四.flex佈局

1. 須要給父級div設置display: flex屬性。
2. 固定寬度的div設置flex: 0 0 200px便可。

3. 內容區域的div直接寫出flex: 1便可。

   .container{
       display: flex;
   }
   .aside{
       flex: 0 0 200px;
       background-color: red; 
   }
   .content{
       flex: 1;
       background-color: blue;
   }
   <div class="container">
       <div class="aside">
       Lorem ipsum dolor sit amet, consectetur adipisicing elit. Labore provident dolor in voluptatum tempore non, placeat obcaecati totam ut delectus libero excepturi distinctio asperiores odit nobis soluta, esse aspernatur beatae.
       </div>
       <div class="content">
       Lorem ipsum dolor sit amet, consectetur adipisicing elit. Labore provident dolor in voluptatum tempore non, placeat obcaecati totam ut delectus libero excepturi distinctio asperiores odit nobis soluta, esse aspernatur beatae.
       </div>
   </div>

五.左側浮動，右側overflow:hidden

.aside{
    width: 200px;
    float: left;
    background-color: red;
}
.content{
    overflow: hidden;
    background-color: blue;
}
<div class="aside">
        Lorem ipsum dolor sit amet, consectetur adipisicing elit. Labore provident dolor in voluptatum tempore non, placeat obcaecati totam ut delectus libero excepturi distinctio asperiores odit nobis soluta, esse aspernatur beatae.
    </div>
    <div class="content">
        Lorem ipsum dolor sit amet, consectetur adipisicing elit. Labore provident dolor in voluptatum tempore non, placeat obcaecati totam ut delectus libero excepturi distinctio asperiores odit nobis soluta, esse aspernatur beatae.
    </div>

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