Check out example codes for "css class". It will help you in understanding the concepts better.

Code Example 1

<ul class="legend">
    <li><span class="greendot"></span>Text</li><br></br>
    <li><span class="yellowdot"></span>Text</li><br></br>
    <li><span class="reddot"></span>Text</li><br></br>
    <li><span class="blackdot"></span>Text</li><br></br>
</ul>

Code Example 2

.ThisIsAClassName{
  font-family: sans-serif;
}

Code Example 3

<p class="ThisIsAClassName">HI</p>

Code Example 4

<p class="ClassExample">ClassExample!!</p>

Code Example 5

.myclass {
  border:1px solid black;
  background-color: #d2d2d2;
  height:20px;
  width:60px;
}
/*If you give this class to a div in html, it will get the styles you gave
to that class. You can add multiple classes to a div, and multiple divs
can get that class. */
/* I hope I helped! */

Code Example 6

<p class="haut">
<a href="#haut">Haut de page</a>
</p>

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