css3背景渐变
1.线性渐变
<style>.box {width: 200px;height: 200px;border: 1px solid black;float: left;margin-left: 50px;}.box1 {background-image: linear-gradient(green, yellow, red);}/* 右上 */.box2 {background-image: linear-gradient(to right top, green, yellow, red);}.box3 {background-image: linear-gradient( 60deg, green, yellow, red);}.box4 {background-image: linear-gradient(green 50px, yellow 100px, red 150px);}.box5 {background-image: linear-gradient(20deg, green 50px, yellow 100px, red 150px);font-size: 80px;font-weight: bold;line-height: 200px;color: transparent;-webkit-background-clip: text;}</style>
<body><div class="box box1">box1</div><div class="box box2">box2</div><div class="box box3">box3</div><div class="box box4">box4</div><div class="box box5">hello</div>
</body>
2.径向渐变
<style>.box {width: 200px;height: 150px;border: 1px solid black;float: left;margin-left: 50px;}.box1 {/* 默认情况 */background-image: radial-gradient(red, yellow, green);}.box2 {/* 圆心在右上角 */background-image: radial-gradient(at right top, red, yellow, green);}.box3 {/* 圆心在（20，40） */background-image: radial-gradient(at 20px 40px,red, yellow, green);}.box4 {/* 通过circle，调整为⚪ */background-image: radial-gradient(circle,red, yellow, green);}.box5 {/* 圆半径是 100 50，圆心位置（120，60） */background-image: radial-gradient(100px 50px at 120px 60px ,red, yellow, green);}</style>
<body><div class="box box1">默认</div><div class="box box2">调整径向圆心</div><div class="box box3">通过左边调整中心位置</div><div class="box box4">通过circle，调整为⚪ </div><div class="box box5"> 圆半径是 100 50，圆心位置（120，60）</div>
</body>
3.重复渐变
无论线性渐变，还是径向渐变，在没有发生渐变的位置，继续进行渐变，就为重复渐变。
利用重复渐变实现网格效果
代码如下：
.box {width: 600px;height: 800px;padding: 20px;border: 1px solid black;position: absolute;margin: auto;top: 0;bottom: 0;left: 0;right: 0;background-image: repeating-linear-gradient(transparent 0, transparent 29px, #333 30px);background-clip: content-box;}<div class="box"></div>