A、 background:linear-gradient(225deg,rgba(0,0,0,1),rgba(255,255,255,1));
B、 background:linear-gradient(-135deg,hsla(120,100%,0%,1),hsla(240,100%,100%,1));
C、 background:linear-gradient(to top left,white,black);
D、 background: linear-gradient(to bottom left, white, black);