footer at bottom of body

1#footer {
2  position: relative;
3  margin-top: -180px;
4  /* negative value of footer height */
5  height: 180px;
6  clear: both;
7 /*Custom styling*/
8}
9
10/* Opera Fix thanks to Maleika (Kohoutec) */
11
12body:before {
13  content: "";
14  height: 100%;
15  float: left;
16  width: 0;
17  margin-top: -32767px;
18  /* thank you Erik J - negate effect of float*/
19}

1html, body {
2  height: 100%;
3}
4body {
5  display: flex;
6  flex-direction: column;
7}
8.content {
9  flex: 1 0 auto;
10}
11.footer {
12  flex-shrink: 0;
13}