.classname vs .clasname #id vs .classname#id

1. .classname:

   • This selector targets all elements with the class classname.

   • Example:

     <div class="classname">This div will be styled</div>
     <p class="classname">This paragraph will also be styled</p>

     .classname {
       color: green;
     }

     Both the <div> and the <p> elements will have their text color set to green because they both have the class classname.

2. .classname #id:

   • This selector targets an element with the id id that is a descendant of an element with the class classname.

   • Example:

     <div class="classname">
       <p id="id">This paragraph will be styled</p>
     </div>
     <div>
       <p id="id">This paragraph will not be styled</p>
     </div>

     .classname #id {
       color: blue;
     }

     Only the first <p> with the id id will have its text color set to blue because it is a descendant of an element with the class classname.

3. .classname#id (without a space between the class and id):

• This selector targets an element that has both the class classname and the id id.

• Example:

  <div class="classname" id="id">This div will be styled</div>
  <div class="classname">This div will not be styled</div>
  <div id="id">This div will not be styled</div>

  .classname#id {
    color: blue;
  }

  Only the first <div> will have its text color set to blue because it has both the class classname and the id id.