@phoenix-plugin-registry/brackets-markdown-preview/styles/preview.css

Markdown live preview incl. detached window, code syntax highlighting, output themes, adaptive preview width, graphical checkboxes, activation on start...

/* ensure that the "checkboxes" (if any) are not reacting to user input and thus cannot be manually checked/unchecked */
input[type="checkbox"].mdcbx { pointer-events: none; }
/* overrides the width of the preview CONTENT in order to fill up to 90% of the space available within the preview PANEL */
body.adaptive {width: 100%; max-width: 90%; margin: 10px auto;}