border-bottom: solid 3px transparent;

border-image: -o-linear-gradient(to right, #ff9000, #ff5000)

1 1

;

border-image: -moz-linear-gradient(to right, #ff9000, #ff5000)

1 1

;

border-image: -webkit-linear-gradient(to right, #ff9000, #ff5000)

1 1

;

border-image: linear-gradient(to right, #ff9000, #ff5000)

1 1

;

模拟器里面显示正常，只有下边框有渐变图片。IOS真机里面会全部边框都显示