Tidy up, and remove redudant css

- Tidy up main.css
- Remove CSS that is no longer relevant. e.g:
 - nav list-style-type, padding, hrs
 - ul inline-block, and padding
 - ul p

main.css

@@ -1,6 +1,5 @@
-html{
+html, body {height: 100%;}
-	font-size: 14px;
+html{font-size: 14px;}
-}
 body{
 	margin:0.2rem auto;
 	max-width:48rem;
@@ -11,38 +10,15 @@ h1,h2,h3,h4,h5,h6 {
 	line-height: 1;
 }
 header h1{
-	margin: 0.4rem 0;
 	margin-top: 1.4rem;
 	margin-bottom: 1.2rem;
 }
-
 a{
 	text-decoration: none;
 }
-nav{
-	list-style-type: none;
-	padding: 0;
-}
-nav>a{
-    padding: 0.2rem;
-}
-nav hr{
-	margin: 0;
-}
-
-html, body {
-	height: 100%;
-}
-
 ul{
 	padding-left: 0;
 	list-style-position: inside;
-	display: inline-block;
-	margin: 0;
-}
-ul p{
-	display: inline-block;
-	margin: 0.5rem 0;
 }
 footer p{
 	margin: 0;
@@ -88,11 +64,7 @@ main{
 
 /* For Media over the mobile view */
 @media screen and (min-width: 601px){
-	nav{
-		list-style-type: none;
-	}
 	nav>a{
-		padding: 1rem 0;
 		margin-left: 2rem;
 	}
 	nav>a:first-child{
@@ -104,14 +76,12 @@ main{
 
 /* For Media under the mobile view */
 @media screen and (max-width: 600px){
-	h1, h2, h3, p, nav{
-		text-align: center;
-	}
-
 	body{
 		margin: 0.2rem;
+		text-align: center;
 	}
 	nav>a{
+		padding: 0.2rem 0;
 		display: block;
 		border-top: 1px dotted black;
 	}