p5.js-web-editor/client/styles/components/_p5-widget-codemirror-theme.scss

:root {
  --light-gray: #A0A0A0;
  --dark-gray: #666;
  --almost-black: #222;
  --dark-brown: #704F21;
  --light-brown: #a67f59;
  --pinkish: #DC3787; /* not p5 pink, but related */
  --dark-blueish: #00A1D3;
}

.cm-s-p5-widget span { color: var(--dark-gray); }

.cm-s-p5-widget span.cm-meta { color: var(--dark-gray); }
.cm-s-p5-widget span.cm-keyword { line-height: 1em; color: var(--dark-brown); }
.cm-s-p5-widget span.cm-atom { color: var(--pinkish); }
.cm-s-p5-widget span.cm-number { color: var(--pinkish); }
.cm-s-p5-widget span.cm-def { color: var(--dark-blueish); }
.cm-s-p5-widget span.cm-variable { color: var(--dark-blueish); }
.cm-s-p5-widget span.cm-variable-2 { color: var(--almost-black); }
.cm-s-p5-widget span.cm-variable-3 { color: var(--almost-black); }
.cm-s-p5-widget span.cm-property { color: var(--almost-black); }
.cm-s-p5-widget span.cm-operator { color: var(--light-brown); }
.cm-s-p5-widget span.cm-comment { color: var(--light-gray); }
.cm-s-p5-widget span.cm-string { color: var(--dark-blueish); }
.cm-s-p5-widget span.cm-string-2 { color: var(--dark-blueish); }

.cm-s-p5-widget span.cm-error { color: #f00; }

.cm-s-p5-widget .CodeMirror-activeline-background { background-color: #e8f2ff; }
// .cm-s-p5-widget .CodeMirror-activeline-gutter { background-color: #e8f2ff; }
.cm-s-p5-widget .CodeMirror-matchingbracket { outline:1px solid grey; color:black !important; }

/* These styles don't seem to be set by CodeMirror's javascript mode. */

.cm-s-p5-widget span.cm-qualifier { color: #555; }
.cm-s-p5-widget span.cm-builtin { color: #30a; }
.cm-s-p5-widget span.cm-bracket { color: #cc7; }
.cm-s-p5-widget span.cm-tag { color: #170; }
.cm-s-p5-widget span.cm-attribute { color: #00c; }
.cm-s-p5-widget span.cm-link { color: #219; }