--iron-collapse-transition-duration is not obvious to find for peoples, it could be exposed in the documentation.
Also, I personally think the default transition duration is quite aggressive for paper-submenu and the effect smoother around 500-700ms. What about
--iron-collapse-transition-duration(paper-submenu-transition-duration, 600ms) ?
--iron-collapse-transition-duration
is not obvious to find for peoples, it could be exposed in the documentation.Also, I personally think the default transition duration is quite aggressive for paper-submenu and the effect smoother around 500-700ms. What about
--iron-collapse-transition-duration(paper-submenu-transition-duration, 600ms)
?