代码示例:(标识:css_form_color)
<!DOCTYPE html>
<html>
<head>
<style> 
input[type=text] {
  width: 100%;
  padding: 12px 20px;
  margin: 8px 0;
  box-sizing: border-box;
  border: none;
  background-color: #3CBC8D;
  color: white;
}
</style>
</head>
<body>

<p>有颜色的文本字段:</p>

<form>
  <label for="fname">First Name</label>
  <input type="text" id="fname" name="fname" value="Bill">
  <label for="lname">Last Name</label>
  <input type="text" id="lname" name="lname" value="Gates">
</form>

</body>
</html>
运行结果: