doc: remove unused CSS files

I could not find them referenced anywhere.

Signed-off-by: Pekka Paalanen <pekka.paalanen@collabora.com>

doc/publican/html/css/brand.css

@@ -1,14 +0,0 @@
-/*headings*/
-h1, h2, h3, h4, h5, h6,
-div.producttitle,
-div.subtitle,
-div.author div.author,
-div.translator div.translator,
-div.othercredit div.othercredit,
-div.editor div.editor,
-div.contrib div.contrib,
-.title,
-.titlepage .edition,
-.titlepage .releaseinfo {
-	color: #336699;
-}

doc/publican/html/css/epub.css

@@ -1,115 +0,0 @@
-/*headings*/
-h1, h2, h3, h4, h5, h6,
-div.producttitle,
-div.subtitle,
-div.author div.author,
-div.translator div.translator,
-div.othercredit div.othercredit,
-div.editor div.editor,
-div.contrib div.contrib,
-.title,
-.titlepage .edition {
-}
-
-div.para {
-	margin-top: 1em;
-}
-/* inline syntax highlighting */
-.perl_Alert {
-	color: #0000ff;
-}
-
-.perl_BaseN {
-	color: #007f00;
-}
-
-.perl_BString {
-	color: #5C3566;
-}
-
-.perl_Char {
-	color: #ff00ff;
-}
-
-.perl_Comment {
-	color: #888888;
-}
-
-
-.perl_DataType {
-	color: #0000ff;
-}
-
-
-.perl_DecVal {
-	color: #00007f;
-}
-
-
-.perl_Error {
-	color: #ff0000;
-}
-
-
-.perl_Float {
-	color: #00007f;
-}
-
-
-.perl_Function {
-	color: #007f00;
-}
-
-
-.perl_IString {
-	color: #5C3566;
-}
-
-
-.perl_Keyword {
-	color: #002F5D;
-}
-
-
-.perl_Operator {
-	color: #ffa500;
-}
-
-
-.perl_Others {
-	color: #b03060;
-}
-
-
-.perl_RegionMarker {
-	color: #96b9ff;
-}
-
-
-.perl_Reserved {
-	color: #9b30ff;
-}
-
-
-.perl_String {
-	color: #5C3566;
-}
-
-
-.perl_Variable {
-	color: #0000ff;
-}
-
-
-.perl_Warning {
-	color: #0000ff;
-}
-
-b, strong {
-	font-weight: bolder;
-}
-
-code.command {
-	font-family: monospace;
-	font-weight: bolder;
-}

doc/publican/html/css/meson.build

@@ -1,9 +1,6 @@
 foreach src : files([
-	'brand.css',
 	'common.css',
 	'default.css',
-	'epub.css',
-	'print.css',
 ])
 	name = fs.name(src)
 	publican_inputs += fs.copyfile(

doc/publican/html/css/print.css

@@ -1,15 +0,0 @@
-@import url("common.css");
-@import url("overrides.css");
-@import url("lang.css");
-
-#tocframe {
-	display: none;
-}
-
-body.toc_embeded {
-	margin-left: 30px;
-}
-
-.producttitle {
-	color: #336699;
-}