用渐变画两个直角梯形
background: linear-gradient(73.1deg,#e8ecf8 50%,#378adb 0);
/**消除锯齿*/
background: linear-gradient(73.1deg,#e8ecf8 50%,#378adb calc(50% + 1px));
background: linear-gradient(73.1deg,#e8ecf8 50%,#378adb 0);
/**消除锯齿*/
background: linear-gradient(73.1deg,#e8ecf8 50%,#378adb calc(50% + 1px));