<div class="container">
  <p>The dimensions of this element transition from one value to another when u hover over it.</p>
  <div class="element element-1"></div>
  <p>Without transitions, the dimensions would "jump" between values:</p>
  <div class="element element-2"></div>
</div>
body {
  background-color: #F5F5F5;
  color: #555;
  font-size: 1.1em;
  font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif;
}

.container {
  margin: 40px auto;
  width: 100%;
  max-width: 700px;
}

.element {
  padding: 20px;
  background-color: #0099cc;
  color: white;
  width: 100px;
  height: 100px;
}

.element-1 {
  -webkit-transition: all .6s ease;
  transition: all .6s ease;
}

.element:hover {
  width: 95%;
}