``` .submit { background: rgba(250, 108, 106, 1); border-radius: 26px; margin-top: 60px; height: 50px; line-height: 50px; text-align: center; color: #fff; font-weight: 500; font-size: 24px; cursor: pointer; position: relative; overflow: hidden; } .submit:after { position: absolute; left: \-100%; /\*改变left的值，让其相对box影藏\*/ top: 0; width: 100%; height: 50px; content: ""; /\* Safari 5.1 - 6.0 \*/ background: \-webkit-linear-gradient(left, rgba(255, 255, 255, 0) 0, rgba(255, 255, 255, .3) 50%, rgba(255, 255, 255, 0) 100%); /\* Opera 11.1 - 12.0 \*/ background: \-o-linear-gradient(left, rgba(255, 255, 255, 0) 0, rgba(255, 255, 255, .3) 50%, rgba(255, 255, 255, 0) 100%); /\* Firefox 3.6 - 15 \*/ background: \-moz-linear-gradient(left, rgba(255, 255, 255, 0) 0, rgba(255, 255, 255, .3) 50%, rgba(255, 255, 255, 0) 100%); /\* 标准的语法 \*/ background: linear-gradient(to right, rgba(255, 255, 255, 0) 0, rgba(255, 255, 255, .3) 50%, rgba(255, 255, 255, 0) 100%); } .submit:hover:after { left: 150%; transition: 1s ease; } ```