Small issues in JS and CSS loading _ basic knowledge

Some minor issues in JS and CSS loading may have been forgotten by everyone. Let's repeat them with you. If you are interested, do not miss out on the js script. There are two windows. onload

The Code is as follows:

Window. onload = function (){
Alert ("aaa ");
};

Window. onload = function (){
Alert ("bbb ");
};

Only one will be executed. This is the setting of the function itself. It is worth noting that the pop-up is not aaa, but bbb, and the last one is executed.

In the css file, in the css style

The Code is as follows:

# Checks {
Padding-left: 20px; padding-top: 16px; margin: auto;
}
# Checks {
Padding-left: 80px; padding-top: 38px; margin: auto;
}

It is also effective for the following style. If the padding-left in the second is removed, the padding-left in the first one is used.

HTML Tag



This is the first one to take effect. It is different from the two above.

I hope someone can explain it...