如何让垂直渐变背景适用于所有浏览器？

background: linear-gradient(to bottom, #ff0000, #0000ff);

background: #ff0000; /* 老版本浏览器的颜色 */
background: -webkit-gradient(linear, left top, left bottom, color-stop(0%, #ff0000), color-stop(100%, #0000ff)); /* Chrome, Safari 4+ */
background: -webkit-linear-gradient(top, #ff0000, #0000ff); /* Chrome 10+, Safari 5.1+ */
background: -moz-linear-gradient(top, #ff0000, #0000ff); /* Firefox 3.6+ */
background: -ms-linear-gradient(top, #ff0000, #0000ff); /* IE 10+ */
background: -o-linear-gradient(top, #ff0000, #0000ff); /* Opera 11.10+ */
background: linear-gradient(to bottom, #ff0000, #0000ff); /* 标准的线性渐变 */