Split line/break/next row in html </tr> <tr> isn't working?

Split line/break/next row in html </tr> <tr> isn't working? 

Hi I have this for some custom buttons in reaper web browser interface: </tr> <tr> <div class="action" onClick="wwr_req('_f68ed7101fef3040bdd49f6869495c8 f')">Strings</div> <div class="action" onClick="wwr_req('_94aaf00781207f4299b28cd39eabb0d 8')">Violin</div> <div class="action" onClick="wwr_req('_79097614db4bc04e917ea054000b09c 1')">Violin 2</div> <div class="action" onClick="wwr_req('_d6f6b2bfb6d66a40a6e7ed16189f37e 5')">Viola</div> <div class="action" onClick="wwr_req('_7a77891dfec2a64384c76f3a9af75ad 8')">Cello</div> <div class="action" onClick="wwr_req('_fcd2808bfd571d4c87cb092fc43d2e1 b')">Bass(DB)</div> </tr> <tr> The tr's aren't breaking the line as i want them to. Any idea why? I'm not super good with html, but i looked up the code to break lines and am struggling. Any help would be appriciated. These are in actions are in boxes currently. I want it eventually to look similar to junkie xls touchscreen for cubase. with the borders around areas and such... But for now just want to break the line for each section "strings" "woodwinds" on each line.

Thank you. Even after figuring out how to close lines. I'm still struggling with organizing the page how i want it to look. It makes another large button, but doesn't start a new line, since each button has it's own borders. Not really sure how to go about altering this to start new rows/breaking a line to put buttons on a new line. I look up the answers, but usually, it's just for text and doesn't really work for my buttons. I'm struggling to find some resources specifically for reaper on this topic, specifically for what I'm doing in html for reaper or any daw. Any suggestions? Should I hop over to lemur instead of html stuff maybe?