Animated Progress Bars in pure CSS

fiddle.css

.container {
  margin: 60px auto;
  width: 400px;
  text-align: center;
}

.container .progress {
  margin: 0 auto;
  width: 400px;
}

.progress {
  padding: 4px;
  background: rgba(0, 0, 0, 0.25);
  border-radius: 6px;
  -webkit-box-shadow: inset 0 1px 2px rgba(0, 0, 0, 0.25), 0 1px rgba(255, 255, 255, 0.08);
  box-shadow: inset 0 1px 2px rgba(0, 0, 0, 0.25), 0 1px rgba(255, 255, 255, 0.08);
}

.progress-bar {
  height: 16px;
  border-radius: 4px;
	background-image: -webkit-linear-gradient(top, rgba(255, 255, 255, 0.3), rgba(255, 255, 255, 0.05));
  background-image: -moz-linear-gradient(top, rgba(255, 255, 255, 0.3), rgba(255, 255, 255, 0.05));
  background-image: -o-linear-gradient(top, rgba(255, 255, 255, 0.3), rgba(255, 255, 255, 0.05));
  background-image: linear-gradient(to bottom, rgba(255, 255, 255, 0.3), rgba(255, 255, 255, 0.05));
  -webkit-transition: 0.4s linear;
  -moz-transition: 0.4s linear;
  -o-transition: 0.4s linear;
  transition: 0.4s linear;
  -webkit-transition-property: width, background-color;
  -moz-transition-property: width, background-color;
  -o-transition-property: width, background-color;
  transition-property: width, background-color;
  -webkit-box-shadow: 0 0 1px 1px rgba(0, 0, 0, 0.25), inset 0 1px rgba(255, 255, 255, 0.1);
  box-shadow: 0 0 1px 1px rgba(0, 0, 0, 0.25), inset 0 1px rgba(255, 255, 255, 0.1);
}

#five:checked ~ .progress > .progress-bar {
  width: 5%;
  background-color: #f63a0f;
}

#twentyfive:checked ~ .progress > .progress-bar {
  width: 25%;
  background-color: #f27011;
}

#fifty:checked ~ .progress > .progress-bar {
  width: 50%;
  background-color: #f2b01e;
}

#seventyfive:checked ~ .progress > .progress-bar {
  width: 75%;
  background-color: #f2d31b;
}

#onehundred:checked ~ .progress > .progress-bar {
  width: 100%;
  background-color: #86e01e;
}

.radio {
  display: none;
}

.label {
  display: inline-block;
  margin: 0 5px 20px;
  padding: 3px 8px;
  color: #aaa;
  text-shadow: 0 1px black;
  border-radius: 3px;
  cursor: pointer;
}

.radio:checked + .label {
  color: white;
  background: rgba(0, 0, 0, 0.25);
}

fiddle.html

<div class="container">
  <input type="radio" class="radio" name="progress" value="five" id="five">
  <label for="five" class="label">5%</label>

  <input type="radio" class="radio" name="progress" value="twentyfive" id="twentyfive" checked>
  <label for="twentyfive" class="label">25%</label>

  <input type="radio" class="radio" name="progress" value="fifty" id="fifty">
  <label for="fifty" class="label">50%</label>

  <input type="radio" class="radio" name="progress" value="seventyfive" id="seventyfive">
  <label for="seventyfive" class="label">75%</label>

  <input type="radio" class="radio" name="progress" value="onehundred" id="onehundred">
  <label for="onehundred" class="label">100%</label>

  <div class="progress">
    <div class="progress-bar"></div>
  </div>
</div>