How to solve problems in the layout?

Recently started learning how to typeset. Made up the regular site.
There are some problems in the layout:
1)how to press the basement to the bottom,like I was doing everything right,but I can't.
2)when selecting one of the items in the select statement,you receive the unit,but the text at the bottom which floats somewhere downwards.
Who is not difficult,ask for help,and be good to point out the errors in html code,which most likely is)
September 19th 19 at 13:05
3 answers
September 19th 19 at 13:07
On the first point, I do trail.follows:


html { height: 100%; }
body { position: relative; min-height: 100%; padding-bottom: 300px; }
footer { position: absolute; bottom: 0; height: 300px; }
Very bad advice. Demonstrates a misunderstanding of the box model. - Tomas24 commented on September 19th 19 at 13:10
September 19th 19 at 13:09
Rather, the drop-down menu should be absolute positioning. Or just leave the place to the menu.
September 19th 19 at 13:11
1 case:
#footer {
position: fixed;
left: 0px;
bottom: 2px;
height: 30px;
width: 100%;

2 not quite understand what is required of us.

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