1

* {
    box-sizing: border-box;
}
body {
    margin: 0;
}
.header {
    background-color: #2196F3;
    color: white;
    text-align: center;
    padding: 15px;
}
.footer {
    background-color: #444;
    color: white;
    padding: 15px;
}
.topmenu {
    list-style-type: none;
    margin: 0;
    padding: 0;
    overflow: hidden;
    background-color: #777;
}
.topmenu li {
    float: left;
}
.topmenu li a {
    display: inline-block;
    color: white;
    text-align: center;
    padding: 16px;
    text-decoration: none;
}
.topmenu li a:hover {
    background-color: #222;
}
.topmenu li a.active {
    color: white;
    background-color: #4CAF50;
}
.column {
    float: left;
    padding: 15px;
}
.clearfix::after {
    content: "";
    clear: both;
    display: table;
}
.sidemenu {
    width: 25%;
}
.content {
    width: 75%;
}
.sidemenu ul {
    list-style-type: none;
    margin: 0;
    padding: 0;
}
.sidemenu li a {
    margin-bottom: 4px;
    display: block;
    padding: 8px;
    background-color: #eee;
    text-decoration: none;
    color: #666;
}
.sidemenu li a:hover {
    background-color: #555;
    color: white;
}
.sidemenu li a.active {
    background-color: #008CBA;
    color: white;
}
<!DOCTYPE html>
<html>
<head>
</head>
<body>

<ul class="topmenu">
  <li><a href="#home" class="active">Home</a></li>
  <li><a href="#news">News</a></li>
  <li><a href="#contact">Contact</a></li>
  <li><a href="#about">About</a></li>
</ul>

<div class="clearfix">
  <div class="column sidemenu">
    <ul>
      <li><a href="#flight">The Flight</a></li>
      <li><a href="#city" class="active">The City</a></li>
      <li><a href="#island">The Island</a></li>
      <li><a href="#food">The Food</a></li>
      <li><a href="#people">The People</a></li>
      <li><a href="#history">The History</a></li>
      <li><a href="#oceans">The Oceans</a></li>
    </ul>
  </div>

  <div class="column content">
    <div class="header">
      <h1>The City</h1>
    </div>
    <h1>Chania</h1>
    <p>Chania is the capital of the Chania region on the island of Crete. The city can be divided in two parts, the old town and the modern city.</p>
    <p>You will learn more about responsive web pages in a later chapter.</p>
  </div>
</div>

<div class="footer">
  <p>Footer Text</p>
</div>

</body>
</html>

I compiled this program without overflow:hidden and it wasn't giving the same output,I can't understand why overflow:hidden is necessary here? I even used overflow:auto and it doesnt show scroll so I know that it isn't that the box is too small for data. It is present in the top menu. I am a newbiee to CSS and it is really confusing for me that why do they have two classes for some elements, why do they use box-sizing, And please edit if there is any problem with the way I have asked,because downvoting it prohibits me from asking questions and - renders me helpless.

Derek Brown
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Therebelentropy
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1 Answers1

0

I am an experienced CSS user, and this took a while for me to find. The .topbar element is a ul without a defined height, and so it looks to child elements to determine the height. However, as your elements inside are using float, the parent is not resized.

As this previous answer discusses, overflow: none, is a hack to solve this problem. However, I don't think this is the best approach in your case. I would either:

  1. Define a constant height for your topbar
  2. Use flexbox instead of ul
Derek Brown
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