①absolute locate：http://www.runoob.com/try/try.php?filename=trycss_position_absolute
②fixed locate：http://www.runoob.com/try/try.php?filename=trycss_position_fixed
③relative locate：http://www.runoob.com/try/try.php?filename=trycss_position_relative
http://www.runoob.com/try/try.php?filename=trycss_position_relative2
④static locate：http://www.runoob.com/try/try.php?filename=trycss_position_static
⑤sticky locate：http://www.runoob.com/try/try.php?filename=trycss_position_sticky
⑥inherit locate：继承
⑦initial locate：初始化为默认值
# Overlapping elements（重叠的元素）using z-index to solute：http://www.runoob.com/try/try.php?filename=trycss_zindex