作业中的nav导航条和banner之间有缝隙

首页课程实战体系课手记专栏慕课教程

来源：4-6 自由编程

西瓜拌西瓜

2020-12-10 21:45:57

# 具体遇到的问题
老师好，这里有两个问题想请您帮忙解决一下。

1、为什么我的这个导航页和banner图片中间会有一条缝隙？

2、然后textarea的placeholder显示不出来。

谢谢。
# 报错信息的截图

# 尝试过的解决思路和结果
css文件中添加了

* {

margin: 0;

padding: 0;

}

# 粘贴全部相关代码，切记添加代码注释（请勿截图）

<!doctype html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport"
          content="width=device-width, user-scalable=no, initial-scale=1.0, maximum-scale=1.0, minimum-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>Career Builder</title>
    <meta name="Keywords" content="">
    <meta name="Description" content="">
    <link rel="stylesheet" href="css/css.css">
</head>
<body>
    
    <header class="top">
        
        <div class="logo">
            <h1>Career Builder</h1>
        </div>
        
        <nav class="main-nav">
            <ul>
                <li><a>HOME</a></li>
                <li><a>ABOUT</a></li>
                <li><a>GALLERY</a></li>
                <li><a>FACULTY</a></li>
                <li><a>EVENTS</a></li>
                <li><a>CONTACT</a></li>
            </ul>
        </nav>
    </header>

    
    <section class="banner">
        <img src="images/banner3.jpg" class="banner-img">
            <div class="center">
                <form action="" method="post">
                    <input class="inputname" type="text" placeholder="your Name">
                    <input class="inputphone" type="text" placeholder="your Phone">
                    <input class="inputemail" type="email" placeholder="your Email">
                    <textarea class="inputarea" cols="15" rows="5" placeholder="Write Your Content Here">
                    </textarea>
                    <input class="buttom" type="submit" value="SEND MESSAGE">
                </form>
            </div>
    </section>
</body>
</html>

# css.css
* {
    margin: 0;
    padding: 0;
}
ul, ol {
    list-style: none
}
a {
    text-decoration: none
}
/* 最上面的青色横条 */
body header.top {
    width: 100%;
    height: 80px;
    background-color: #07cbc9;
    margin: 0 auto;
}
/* 网页最左上角的logo */
header div.logo {
    float: left;
    height: 48px;
    margin: 16px 70px;
}
/* logo的字体大小和颜色 */
header div.logo h1 {
    font-size: 38px;
    color: white;
}
/* 整个导航条 */
header nav.main-nav ul {
    float: right;
    width: 750px;
    height: 80px;
}
/* 导航条中的每一个链接 */
header nav.main-nav ul li {
    float: left;
    width: 115px;
    font-size: 16px;
    color: white;
    text-align: center;
    /* 行高等于盒子高 */
    line-height: 80px;
}
/* a标签转换宽高，这样能够点击的范围就更大 */
header nav.main-nav ul li a {
    display: block;
    width: 115px;
    height: 80px;
    font-size: 16px;
    color: white;
    cursor: pointer;
}
header nav.main-nav ul li a:hover {
    background-color: orange;
}

/* Banner */
.banner {
    position: relative;
    width: 100%;
    margin: 0 auto;
}
/* banner长条大图 */
.banner .banner-img {
    width: 100%;
    height: 600px;
}
/* 遮罩层 */
.banner .center {
    position: absolute;
    width: 100%;
    height: 600px;
    top: 50%;
    margin-top: -300px;
    background-color: rgba(0, 0, 0, 0.5)
}
/* 表单的大框 */
section div form {
    position: absolute;
    width: 600px;
    height: 600px;
    top: 50%;
    left: 50%;
    margin-top: -300px;
    margin-left: -300px;

}
/* 表单的每一个输入框*/
.banner .center .inputname {
    position: absolute;
    display: block;
    width: 504px;
    height: 40px;
    top: 100px;
    left: 50%;
    margin-left: -252px;
    background: none;
}
.banner .center .inputphone {
    position: absolute;
    display: block;
    width: 504px;
    height: 40px;
    top: 160px;
    left: 50%;
    margin-left: -252px;
    background: none;
}
.banner .center .inputemail {
    position: absolute;
    display: block;
    width: 504px;
    height: 40px;
    top: 220px;
    left: 50%;
    margin-left: -252px;
    background: none;
}
.banner .center .inputarea {
    position: absolute;
    display: block;
    width: 504px;
    height: 110px;
    top: 280px;
    left: 50%;
    margin-left: -252px;
    resize: none;
    background: none;
}
.banner .center .buttom {
    position: absolute;
    display: block;
    width: 200px;
    height: 40px;
    top: 460px;
    left: 50%;
    margin-left: -100px;
    background: none;
}