Header background padding not changing in #media - css

Question

I'm fairly new to the world of scripts and coding, so I do not know the best terms to use.
I am trying to make a somewhat simple website, and I want my header background to have padding-bottom 120px at min-width 600px, and 0 at 1050. However, the padding-bottom only updates when changed in the properties for header.
Here is my code:
header {
border-radius: 5px;
display: block;
width: auto;
min-height: 200px;
background: #E44;
padding-top: 40px;
padding-left: 38px;
padding-right: 38px;
padding-bottom: 136px;
}
#media screen and (min-width: 600px) {
.header {
padding-bottom:120px
}
}
#media screen and (min-width: 1050px) {
.header {
padding-bottom: 0px;
}
}
The padding-bottom stays at 136px no matter the min-width of the window.

Answer 1

Make sure that you know the difference the dot does. .header is selection the header class. While header selects the element. Your code works fine, as you can see here, I'm using the media queries to change the background color instead of padding, just to make the point clear.
Fiddle example
header {
border-radius: 5px;
display: block;
width: auto;
min-height: 200px;
background: #E44;
padding-top: 40px;
padding-left: 38px;
padding-right: 38px;
padding-bottom: 136px;
}
#media screen and (min-width: 600px) {
.header {
background-color: blue;
}
}
#media screen and (min-width: 1050px) {
.header {
background-color: green;
}
}
<header class="header">
</header>

Answer 2

There is a small typo here. You have an additional dot(.) which will mean a class selector as against the other style which is on element selector.
#media screen and (min-width: 600px) {
header {
padding-bottom:120px
}
}
#media screen and (min-width: 1050px) {
header {
padding-bottom: 0px;
}
}