WP File Manager

Name	Action
..
block.json	Edit
editor-rtl.css	Edit
editor-rtl.min.css	Edit
editor.css	Edit
editor.min.css	Edit
style-rtl.css	Edit
style-rtl.min.css	Edit
style.css	Edit
style.min.css	Edit
theme-rtl.css	Edit
theme-rtl.min.css	Edit
theme.css	Edit
theme.min.css	Edit

Editing: editor.css

.wp-block-audio{ margin-left:0; margin-right:0; position:relative; } .wp-block-audio.is-transient audio{ opacity:.3; } .wp-block-audio .components-spinner{ left:50%; margin-left:-9px; margin-top:-9px; position:absolute; top:50%; }