And here’s the style declaration in the head content. Note that the font sizes are in em, not percentages, and it’s not the same as the github style sheet.
<style id="ocean-gutenberg-style"> /* OceanWP Gutenberg Style */.block-editor .editor-styles-wrapper, .block-editor .editor-styles-wrapper .block-editor-block-list__layout{font-family:Sintony;font-weight:400;font-size:1.5em;color:#3f3f3f;}.block-editor .editor-styles-wrapper .block-editor-block-list__layout h1, .block-editor .editor-styles-wrapper .block-editor-block-list__layout h2, .block-editor .editor-styles-wrapper .block-editor-block-list__layout h3, .block-editor .editor-styles-wrapper .block-editor-block-list__layout h4, .block-editor .editor-styles-wrapper .block-editor-block-list__layout h5, .block-editor .editor-styles-wrapper .block-editor-block-list__layout h6{font-family:Sintony;}.block-editor .editor-styles-wrapper .block-editor-block-list__layout h1, .block-editor .editor-styles-wrapper .block-editor-block-list__layout h1 a{font-size:2em;}.block-editor .editor-styles-wrapper .block-editor-block-list__layout h2, .block-editor .editor-styles-wrapper .block-editor-block-list__layout h2 a{font-size:1.75em;}.block-editor .editor-styles-wrapper .block-editor-block-list__layout h3, .block-editor .editor-styles-wrapper .block-editor-block-list__layout h3 a{font-size:1.6em;}.block-editor .editor-styles-wrapper .block-editor-block-list__layout h4, .block-editor .editor-styles-wrapper .block-editor-block-list__layout h4 a{font-weight:700;font-size:1.5em;}.editor-styles-wrapper .block-editor-block-list__layout a{color:#9dc400;}.editor-styles-wrapper .block-editor-block-list__layout a:hover{color:#0b7cac;}.editor-post-title__block .editor-post-title__input{color:#333333;}</style>