Changes
Also match subpage names beginning with "sandbox", per edit request
{{#if:{{#ifeq:{{#invoke:String|sublength|s={{SUBPAGENAME}}|i=0|len=7}}|sandbox|1}}{{#ifeq:{{SUBPAGENAME}}|doc|1}}{{#invoke:String|match|{{PAGENAME}}|/sandbox/styles.css$|plain=false|nomatch=}}|{{{1|}}}|{{{2|}}}}}<!--
--><noinclude>{{documentation}}</noinclude>