<div class="progress-bar">
  <div class="progress" style="width: 60%;"></div>
</div>

.progress-bar {
  width: 100%;
  height: 20px;
  background-color: #e0e0e0;
  border-radius: 10px;
  overflow: hidden;
  box-shadow: inset 0 1px 3px rgba(0,0,0,0.2);
}
<p>.progress {
height: 100%;
width: 0; /<em> 初始为0，可通过JS或内联样式控制 </em>/
background-color: #4caf50;
border-radius: 10px;
transition: width 0.4s ease; /<em> 平滑动画效果 </em>/
}</p>

.progress-bar {
  position: relative;
  width: 100%;
  height: 30px;
  background-color: #e0e0e0;
  border-radius: 15px;
  overflow: hidden;
  font-family: Arial, sans-serif;
}
<p>.progress {
height: 100%;
width: 75%;
background-color: #2196f3;
border-radius: 15px;
display: flex;
align-items: center;
justify-content: flex-end;
color: white;
font-size: 12px;
padding-right: 10px;
box-sizing: border-box;
}</p>