有效沟通问答-【官方】百战程序员_IT在线教育培训机构

1.html
<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <meta http-equiv="X-UA-Compatible" content="IE=edge" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <title>webxiaode的网页</title>
    <link rel="stylesheet" href="./css/reset.css" />
    <link rel="stylesheet" href="./css/mi.css" />
    <link rel="stylesheet" href="./css/iconfont/iconfont.css" />
  </head>

  <body>
    <!-- 头部开始 -->
    <div class="header">
      <a href="#">
        <img src="./images/top.jpg" alt="" />
      </a>
    </div>
    <!-- 头部结束 -->
    <!-- 黑色导航部分开始 -->
    <!--黑色导航步骤：
            1.主容器.背景颜色
            2.内容部分居中显示，容器处理
            3.左导航，右导航
            4.动画
    -->
    <div class="black-nov">
      <div class="wrop">
        <ul class="black-nov-left">
          <li><a href="#">小米商城</a><span>|</span></li>
          <li><a href="#">MIUI</a><span>|</span></li>
          <li><a href="#">lOT</a><span>|</span></li>
          <li><a href="#">云服务</a><span>|</span></li>
          <li><a href="#">天星科技</a><span>|</span></li>
          <li><a href="#">有品</a><span>|</span></li>
          <li><a href="#">小爱开发平台</a><span>|</span></li>
          <li><a href="#">企业团购</a><span>|</span></li>
          <li><a href="#">资质证照</a><span>|</span></li>
          <li><a href="#">协议规则</a><span>|</span></li>
          <li>
            <a href="#">下载APP</a><span>|</span>
            <div class="download">
              <img src="./images/download.png" alt="" />
              <p>小米商城APP</p>
            </div>
            <div class="stri"></div>
          </li>
          <li><a href="#">智能生活</a></li>
          <li><a href="#">SelectLocation</a></li>
        </ul>
        <ul class="black-nav-right">
          <li><a href="#">登录</a><span>|</span></li>
          <li><a href="#">注册</a><span>|</span></li>
          <li><a href="#">消息通知</a><span>|</span></li>
          <li class="cart">
            <a href="#"> <span class="iconfont">&#xe607;</span>购物车（0）</a>
            <div class="cart-list">购物车中还没有商品，赶紧选购吧！</div>
          </li>
        </ul>
      </div>
    </div>
    <!-- 黑色导航部分结束 -->
  </body>
</html>

2.css样式
* {
  margin: 0;
  padding: 0;
}
/*头部样式开始*/
.header {
  width: 100%;
  height: 120px;
  overflow: hidden;
  position: relative;
}

.header img {
  height: 120px;
  position: absolute;
  left: 50%;
  transform: translateX(-50%);
}
/*头部样式结束*/


/*黑色导航开始*/
.black-nov {
  width: 100%;
  height: 40px;
  line-height: 40px; /*行高为40px*/
  background-color: #333;
  font-size: 12px; /*设置字体大小*/
}/*导航部分*/

.wrop {
  width: 1226px;
  margin: 0 auto;
}

.black-nov-left {
  float: left;
}

.black-nov-right {
  float: right;
}

.black-nov li {
  float: left; /*字体浮动居左*/
  position: relative; /*相对定位*/
}

.black-nov a {
  color: #b0b0b0;
}

.black-nov span {
  color: #424242;
  margin: 0 3.6px;
}

.download {
  width: 124px;
  height: 0;
  background: #fff;
  box-shadow: 0 1px 5px #aaa;
  position: absolute; /*绝对定位*/
  top: 40px;
  left: 50%;
  margin-left: -62px;
  overflow: hidden; /*消除浮动*/
  transition: all 0.3s; /*过渡所有属性*/
}

.download img {
  width: 90px;
  margin: 18px auto 0;
}

.download p {
  color: #333;
  font-size: 14px;
  line-height: 14px;
}

.black-nov-left li:hover > .download {
  height: 148px;
}

.stri {
  width: 0;
  height: 0;
  border-bottom: 8px solid #fff;
  border-left: 8px solid transparent;
  border-right: 8px solid transparent;
  position: absolute; /*绝对定位*/
  bottom: 0;
  left: -50%; /*左右居中*/
  margin-left: 46px;
  display: none; /*默认没有*/
}

.black-nov-left li:hover > .stri {
  display: block;
} /*让它出现*/

.cart {
  width: 120px;
  高度： 40px;
  margin-left: 25px;
  background: #424242;
  position: relative;
}

.cart span{
  color: #b0b0b0;
}

.cart:hover {
  background: #fff;
}

.cart a:hover{
  color: #ff6700;
}

.cart-list {
  width: 316px;
  height: 0;
  background: #fff;
  box-shadow: 0 2px 10px rgb(0, 0, 0,0.15);
  position: absolute; /*绝对定位*/
  top: 40px;
  right: 0;
  颜色 ： #424242;
  overflow: hidden; /*消除浮动*/
  transition: all 0.3s; /*过渡所有属性*/
  行高：100px;
}

.cart:hover>.cart-list{
  高度： 100px;
}
/*黑色导航结束*/

问题：左边导航和右边导航连接在一起了，怎么解决啊

WEB前端全系列/第一阶段：HTML5+CSS3模块/商城官网项目 346楼

.left ul li span{
            float: right;
            }
            为什么不用居右？这样出来的效果也一样的呀

WEB前端全系列/第一阶段：HTML5+CSS3模块/CSS应用技巧 347楼

<i class="one"></i>
i 是属于什么标签？

WEB前端全系列/第一阶段：HTML5+CSS3模块/CSS应用技巧 348楼

缺点的话对分辨率大的显示器有影响会使图片模糊失真，用做图标不可取，使用矢量图标更加友好

WEB前端全系列/第一阶段：HTML5+CSS3模块/CSS应用技巧 349楼

你好，老师我测试下元素后面必须加空格再加：.not() 选择器才能实现功能，而其他的伪类选择器不用加空格直接跟着写就可以，这是为什么呢

WEB前端全系列/第一阶段：HTML5+CSS3模块/CSS选择器 350楼

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        .box{
            width: 50px;
            height: 50px;
            background-color: cornflowerblue;
            font-size: 12px;
            animation: Rotating 5s linear 1;
        }
        @keyframes Rotating {
            0%{
               
            }
            25%{
                transform: rotate(90deg);
            }
            50%{
                transform: translateX(300px);
               
            }
            75%{
                background-color: #ff5500;
            }
            100%{
                transform: translateX(0);
            }
           
        }
    </style>
</head>
<body>

    <div class="box">一个盒子宽高都是50</div>
   
</body>
</html>

为什么我旋转了，移动的时候它又转回去了。

WEB前端全系列/第一阶段：HTML5+CSS3模块/CSS3新特性 351楼

<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        ol > li {
            color: red;
        }
    </style>
</head>
<body>
   <ol>
        <li>合肥</li>
        <li>淮北
            <ol>
                <li>相山区</li>
                <li>濉溪县</li>
                <li>烈山区</li>
            </ol>
        </li>
        <li>巢湖</li>
    </ol>
</body>

</html>

你好，老师。我这个子代选择器的书写li标签里嵌套的ol li标签为什么也生效了，能帮忙看看哪里出了问题吗

WEB前端全系列/第一阶段：HTML5+CSS3模块/CSS选择器 352楼

你好老师，用html构建表格给table一个border属性外边框和单元格都会自动显示边框，而用css来加样式的时候，必须table 和td同时给一个border属性，这样外边框和单元格才会都有边框

WEB前端全系列/第一阶段：HTML5+CSS3模块/CSS常用属性 353楼

你好老师，css的表格属性里折叠边框border-collapse属性是不是相当于表格属性里的callspacing padding属性相当于callpadding

WEB前端全系列/第一阶段：HTML5+CSS3模块/CSS常用属性 354楼

你好，表格属性里的表格边框border属性table,td{border:1px solid black }里面的solid black 什么意思啊，视频中直接就书写也不对其进行解释

WEB前端全系列/第一阶段：HTML5+CSS3模块/CSS常用属性 355楼

老师，一张图片上要呈现出文字，该怎么弄？类似这种。

WEB前端全系列/第一阶段：HTML5+CSS3模块/CSS3新特性 356楼

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <link rel="stylesheet" href="./iconfont.css">
    <style>
        *{
            margin: 0;
            padding: 0;
        }
        body{
            background-color: #f1f1f1;
        }
        .slide{
            width: 234px;
            height: 420px;
            background-color: rgba(105,101,101,0.6);
            padding: 20px 0;
            margin: 100px;
            position: relative;
        }
        .slide ul{
            list-style: none;
        }
        .slide ul li{
            width: 100%;
            height: 42px;
            line-height: 42px;
            text-align: left;
            padding-left: 30px;
            box-sizing: border-box;
        }
        .slide ul li:hover{
            background-color: #ff6700;
           
        }
        .slide ul li a{
            display: inline-block;
            text-decoration: none;          
            color: #fff;
           
        }
       
        .slide .iconfont{
            display: inline-block;
            font-size: 24px;
            color: #fff;
            position: absolute;
            right: 10px;
        }
        .slide-list{
            width: 992px;
            height: 460px;
            background-color: #fff;
            position: absolute;
            top: 0;
            left: 234px;
            border: 1px solid #e0e0e0;
            border-left:none ;
            box-sizing: border-box;
            box-shadow: 0 4px 16px rgba(0,0,0,0.18);
            display: none;
            overflow: hidden;
            clear: both;
        }
        /* 鼠标滑动到li标签上，对应的div出现 */
        .slide ul li:hover>.slide-list{
            display: block;
        }
        .slide-list .text{
            display: block;
            width: 208px;
            height: 70px;
            line-height: 70px;
            /* background-color: red;     */
            float: left;
            margin-left: 30px;
            margin-top: 7px;
            font-size:normal;
        }
        .slide-list .text:hover>i{
            color: #ff6700;

        }
        .slide-list .text img{
            display: inline-block;
            /* 垂直对齐方式 */
            vertical-align: middle;
           
           
        }
        .slide-list .text i{
            font-size:normal;
            display: inline-block;
            color:black;
            font-size: 16px;  
        }
    </style>
</head>
<body>

    <div class="slide">
        <ul>
            <li>
                <a href="#">手机</a>
                <span class="iconfont icon-jiantou"></span>
                <div class="slide-list">
                    <a  class="text" href="#">
                        <img src="./Redmi K50 Pro.webp" >
                        <i>Redmi K50 Pro</i>
                    </a>
                    <a  class="text" href="#">
                        <img src="./Xiaomi 12X.webp" alt="">
                        <i>Xiaomi 12X</i>
                    </a>
                    <a  class="text" href="#">
                        <img src="./Xiaomi Civi.webp" alt="">
                        <i>Xiaomi Civi</i>
                    </a>
                    <a  class="text" href="#">
                        <img src="./Xiaomi 10S.webp" alt="">
                        <i>Xiaomi 10S</i>
                    </a>
                    <a  class="text" href="#">
                        <img src="./Redmi K50 Pro.webp" alt="">
                        <i>Redmi K50</i>
                    </a>
                    <a  class="text" href="#">
                        <img src="./Redmi K50 Pro.webp" >
                        <i>Redmi K50 Pro</i>
                    </a>
                    <a  class="text" href="#">
                        <img src="./Xiaomi 12X.webp" alt="">
                        <i>Xiaomi 12X</i>
                    </a>
                    <a  class="text" href="#">
                        <img src="./Xiaomi Civi.webp" alt="">
                        <i>Xiaomi Civi</i>
                    </a>
                    <a  class="text" href="#">
                        <img src="./Xiaomi 10S.webp" alt="">
                        <i>Xiaomi 10S</i>
                    </a>
                    <a  class="text" href="#">
                        <img src="./Redmi K50 Pro.webp" alt="">
                        <i>Redmi K50</i>
                    </a>
                    <a  class="text" href="#">
                        <img src="./Redmi K50 Pro.webp" >
                        <i>Redmi K50 Pro</i>
                    </a>
                    <a  class="text" href="#">
                        <img src="./Xiaomi 12X.webp" alt="">
                        <i>Xiaomi 12X</i>
                    </a>
                    <a  class="text" href="#">
                        <img src="./Xiaomi Civi.webp" alt="">
                        <i>Xiaomi Civi</i>
                    </a>
                    <a  class="text" href="#">
                        <img src="./Xiaomi 10S.webp" alt="">
                        <i>Xiaomi 10S</i>
                    </a>
                    <a  class="text" href="#">
                        <img src="./Redmi K50 Pro.webp" alt="">
                        <i>Redmi K50</i>
                    </a>
                    <a  class="text" href="#">
                        <img src="./Redmi K50 Pro.webp" >
                        <i>Redmi K50 Pro</i>
                    </a>
                    <a  class="text" href="#">
                        <img src="./Xiaomi 12X.webp" alt="">
                        <i>Xiaomi 12X</i>
                    </a>
                    <a  class="text" href="#">
                        <img src="./Xiaomi Civi.webp" alt="">
                        <i>Xiaomi Civi</i>
                    </a>
                    <a  class="text" href="#">
                        <img src="./Xiaomi 10S.webp" alt="">
                        <i>Xiaomi 10S</i>
                    </a>
                    <a  class="text" href="#">
                        <img src="./Redmi K50 Pro.webp" alt="">
                        <i>Redmi K50</i>
                    </a>
                    <a  class="text" href="#">
                        <img src="./Redmi K50 Pro.webp" >
                        <i>Redmi K50 Pro</i>
                    </a>
                    <a  class="text" href="#">
                        <img src="./Xiaomi 12X.webp" alt="">
                        <i>Xiaomi 12X</i>
                    </a>
                    <a  class="text" href="#">
                        <img src="./Xiaomi Civi.webp" alt="">
                        <i>Xiaomi Civi</i>
                    </a>
                    <a  class="text" href="#">
                        <img src="./Xiaomi 10S.webp" alt="">
                        <i>Xiaomi 10S</i>
                    </a>
                    <a  class="text" href="#">
                        <img src="./Redmi K50 Pro.webp" alt="">
                        <i>Redmi K50</i>
                    </a>
                    <a  class="text" href="#">
                        <img src="./Redmi K50 Pro.webp" >
                        <i>Redmi K50 Pro</i>
                    </a>
                    <a  class="text" href="#">
                        <img src="./Xiaomi 12X.webp" alt="">
                        <i>Xiaomi 12X</i>
                    </a>
                    <a  class="text" href="#">
                        <img src="./Xiaomi Civi.webp" alt="">
                        <i>Xiaomi Civi</i>
                    </a>
                    <a  class="text" href="#">
                        <img src="./Xiaomi 10S.webp" alt="">
                        <i>Xiaomi 10S</i>
                    </a>
                   
                </div>
            </li>
            <li>
                <a href="#">电视</a>
                <span class="iconfont icon-jiantou"></span>
                <div class="slide-list">小米2</div>
            </li>
        </ul>
    </div>
   
</body>
</html>

为什么这个字体我设置的normal但是还是斜体

WEB前端全系列/第一阶段：HTML5+CSS3模块/CSS应用技巧 357楼

你好，老师 option和input标签里面必须书写value属性吗？书写和不书写的区别又是什么呢？

WEB前端全系列/第一阶段：HTML5+CSS3模块/表单 358楼

为什么submit和reset属性后面不需要添加name

WEB前端全系列/第一阶段：HTML5+CSS3模块/表单 359楼

input的name属性是不是随便给一个值都行，只要给取个名字就可以，还是讲name属性的属性值必须是有要求的

WEB前端全系列/第一阶段：HTML5+CSS3模块/表单 360楼

同学您好