Today, I've found that we can adjust background image with percentage in CSS. The time before I knew only to adjust background image with two positions. It's left, right, center and bottom, up position. Now I know is to adjust by percentage for those two positions.
2.mybg {
3background: url("img") no-repeat center left;
4}
Here is modern adjustment
2.mybg {
3background: url("img") no-repeat 50% 25%;
4}
It's cool, isn't it?

Android
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