@former_evernotist I too found the default light theme lacking a little bit of contrast.

Below is some css I have collected over the years to put a bit of contrast into the Joplin light theme. It still seems to work and It also makes the scrollbar easier to see.

I have commented the css so you can remove any bits you do not want / need.

userchrome.css

Click to expand
/* ==Interface modifications== */

::-webkit-scrollbar-thumb {
    /* changes the scrollbar slider colour */
     background: #c0c0c0 !important;
}
 div.note-list-item span {
    /* notelist - note title text */
     color: black !important;
}
 input.title-input {
    /* note - note title text*/
     color: black !important;
}
 a > span.icon-back,
 a > span.icon-forward,
 a > span.icon-share,
 a > span.icon-bold,
 a > span.icon-italic,
 a > span.icon-link,
 a > span.icon-code,
 a > span.icon-attachment,
 a > span.icon-bulleted-list,
 a > span.icon-numbered-list,
 a > span.icon-to-do-list,
 a > span.icon-heading,
 a > i.fa-ellipsis-h,
 a > span.icon-add-date,
 a > span.icon-layout,
 a > span.icon-info {
    /* changes toolbar icon colour - inactive icons are a % of this colour*/
    /* these can be broken out into individual entries if a "rainbow" of colours is wanted*/
     color: black !important;
}
/* Start - the below section is not required if you do not use the "Menu items, Shortcuts, Toolbar icons" plugin */
 a > i.fa-highlighter,
 a > i.fa-strikethrough,
 a > i.fa-underline,
 a > i.fa-superscript,
 a > i.fa-subscript {
    /* changes the "Menu items, Shortcuts, Toolbar icons" **plugin** toolbar icon size and colour - inactive icons are a % of this colour*/
    /* these can be broken out into individual entries if a "rainbow" of colours is wanted*/
     font-size: 1em !important;
     color: black !important;
     font-weight: 600 !important;
}
/* End - the above section is not required if you do not use the "Menu items, Shortcuts, Toolbar icons" plugin */

/* ==CodeMirror editor modifications== */

 span[role="presentation"] {
    /* editor pane text */
     color: black;
}

userstyle.css

Click to expand
 body,
 table th,
 table td {
    /* sets body text, table cell, and header cell font colour */
     color: #000000;
}
 code {
    /* sets code font colour - fenced code, inline code and pre */
     color: #000000;
    /* stops code boxes extending off the note page */
     white-space: pre-wrap;
}
 caption {
    /* puts a table caption underneath the table rather than the default (above) */
     caption-side: bottom;
    /* sets the colour of the table caption */
     color: #000000;
}