I don't like the changed background either, and I had sucessfully turned it off. The relevant section from my user css in Display settings is this. Note "transparent". 

div.readmore { background-color: transparent; padding-left: 2px; borde
+r-left-width: 2px; border-left-color: #080; border-left-style: solid 
+}

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In reply to Re: background in <readmore> tags by ambrus
in thread background in <readmore> tags by John M. Dlugosz

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