title: CSS apply style to empty inputs ([value=''])
body: <p>I would like to apply a special style to all inputs in my form that are required and empty at that. </p>
  
  <p>It does work when i write in my css</p>
  
  <pre><code>input[required='required'] {
      bla-bla-bla;
  }
  </code></pre>
  
  <p>but it doesn't work, when i write</p>
  
  <pre><code>input[value=''] {
     bla-bla-bla;
  }
  </code></pre>
  
  <p>I know i can do that using jQuery, but i would like to do that in pure css, if it is possible. </p>
  
  <p>Can that be done?</p>
  
  <p>Thank you in advance, <br>
  Timofey.</p>