Stylesheet for okayplayer message board and a bookmarklet to apply it using a desktop browser.

bookmarklet.txt

javascript:(( d, w, url ) => { const p = new URLSearchParams(w.location.search); if ( p.has('topic_id') ) {d.body.classList.add('okp-topic');} else if ( p.has( 'forum' ) ) {d.body.classList.add('okp-forum');} fetch( url ) .then( ( r ) => { return r.text(); } ).then( ( css ) => { const style = d.createElement( 'style' ); style.type = 'text/css'; style.appendChild( d.createTextNode(css) ); d.head.appendChild( style ); });})(document, window, 'https://gist.githubusercontent.com/douglas-johnson/aa7992550591896ec0c78615dea60341/raw/okayplayer-stylesheet.css');

okayplayer-stylesheet.css

/**
 * Reset
 */

* {
  box-sizing: border-box;
}

html {
  font-size: 100%;
}

body {
  font-size: 100%;
  line-height: 1.5;
}

#network-bar .sup_header {
  inline-size: auto;
  block-size: auto;
}

table {
  line-height: inherit;
}

table:not(.dctoc),
table:not(.dctoc) :is(thead,tbody,tfoot,tr,td,th) {
  display: block;
  padding: 0;
  inline-size: auto;
}

table,thead,tbody,tfoot,tr,td,th {
  font-size: inherit;
}

br {
  display: none;
}

[align=center] {
  text-align: inherit;
}

[nowrap=nowrap] {
  white-space: inherit;
}

.dcheading, .dclite, .dcdark, .dcdate, .dclink, .dcauthorlink, .dcmisc, .dccaption, .dcauthorinfo, .dcpagelink, .dcsortby, .dcmenu, .dcsubjecttitle, .dcnavmenu, .dctoc, .dctocsubject, .dctocmisc
 {
  font-size: inherit;
}

.dcborder {
  background-color: inherit;
}

.dcborder ~ .dcborder {
  margin-block-start: 1em;
}

body > .dcborder > tbody,
body > table:not(.dcborder) .dcborder > tbody{
  padding-inline-start: 1em;
  padding-inline-end: 1em;
}

/**
 * Forum
 */
.okp-forum tr:is( .dclite, .dcdark ) {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5em;
  padding: 0.5em;
}
  
.okp-forum tr:is( .dclite, .dcdark ) > td:nth-of-type(1) {
  order: 2;
  flex-basis: 18px;
  display: flex;
  flex-direction: column;
  justify-content: center;
}

.okp-forum tr:is( .dclite, .dcdark ) > td:nth-of-type(2) {
  order: 1;
  flex-basis: 100%;
}

.okp-forum tr:is( .dclite, .dcdark ) > td:nth-of-type(3) {
  order: 3;
  flex-basis: calc( 100% - 18px - 0.5em );
}
  
.okp-forum tr:is( .dclite, .dcdark ) > td:nth-of-type(3) ~ td {
   font-size: 0.875em;
}  
  
.okp-forum tr:is( .dclite, .dcdark ) > td:nth-of-type(4) {
  order: 4;
}
  
.okp-forum tr:is( .dclite, .dcdark ) > td:nth-of-type(5) {
  order: 5;
}

.okp-forum tr:is( .dclite, .dcdark ) > td:nth-of-type(5)::before {
  background-image: url('data:image/svg+xml;charset=UTF-8,%3Csvg%20xmlns%3D%22http%3A%2F%2Fwww.w3.org%2F2000%2Fsvg%22%20height%3D%2220px%22%20viewBox%3D%220%200%2024%2024%22%20width%3D%2220px%22%20fill%3D%22%23000000%22%3E%3Cpath%20d%3D%22M0%200h24v24H0z%22%20fill%3D%22none%22%2F%3E%3Cpath%20d%3D%22M20%202H4c-1.1%200-2%20.9-2%202v18l4-4h14c1.1%200%202-.9%202-2V4c0-1.1-.9-2-2-2z%22%2F%3E%3C%2Fsvg%3E');
  inline-size: 1em;
  display: inline-block;
  content: "";
  block-size: 1em;
  vertical-align: middle;
  background-size: cover;
  margin-inline-end: 0.5em;
}

.okp-forum tr:is( .dclite, .dcdark ) > td > div {
  display: inline;
}
  
.okp-forum tr:is( .dclite, .dcdark ) > td:nth-of-type(6) {
  order: 6;
}
  
.okp-forum tr:is( .dclite, .dcdark ) > td:nth-of-type(6)::before {
  background-image: url('data:image/svg+xml;charset=UTF-8,%3Csvg%20xmlns%3D%22http%3A%2F%2Fwww.w3.org%2F2000%2Fsvg%22%20height%3D%2224%22%20viewBox%3D%220%200%2024%2024%22%20width%3D%2224%22%20fill%3D%22%23000000%22%3E%3Cpath%20d%3D%22M0%200h24v24H0z%22%20fill%3D%22none%22%2F%3E%3Cpath%20d%3D%22M12%204.5C7%204.5%202.73%207.61%201%2012c1.73%204.39%206%207.5%2011%207.5s9.27-3.11%2011-7.5c-1.73-4.39-6-7.5-11-7.5zM12%2017c-2.76%200-5-2.24-5-5s2.24-5%205-5%205%202.24%205%205-2.24%205-5%205zm0-8c-1.66%200-3%201.34-3%203s1.34%203%203%203%203-1.34%203-3-1.34-3-3-3z%22%2F%3E%3C%2Fsvg%3E');
  inline-size: 1.5em;
  display: inline-block;
  content: "";
  block-size: 1em;
  background-size: 100% 125%;
  margin-inline-end: 0.25em;
}  

/**
 * Topic
 */
.okp-topic {}

table.dctoc :is(table,thead,tbody,tfoot,tr,td,th) {
  display: revert;
}

table.dctoc table {
  inline-size: 100%;
}

.dctocmisc {
  white-space: nowrap;
}

/**
 * Message
 */
.dcmessage br {
  display: inline;
}

/**
 * Page Link
 */

tr.dcpagelink {
  display: flex;
  flex-wrap: wrap;
  gap: 1em;
  justify-content: space-between;
}

td.dcpagelink{
  inline-size: auto;
  text-align: end;
  flex-grow: 1;
}