function setColorWithTemplate(template) { return function(color) { let custom_theme = JSON.parse(JSON.stringify(template)); custom_theme.block.h1['border-bottom'] = `2px solid ${color}`; custom_theme.block.h2['background'] = color; custom_theme.block.h3['border-left'] = `3px solid ${color}`; custom_theme.inline.strong['color'] = color; return custom_theme }; } let setColor = setColorWithTemplate(default_theme);