ความกว้างของคอลัมน์

{"my_document.Rmd":"---\ntitle: \"Bikeshare\"\noutput: \n  flexdashboard::flex_dashboard:\n    orientation: columns\n---\n\n```{r setup, include=FALSE}\nlibrary(flexdashboard)\n```\n\nColumn\n-----------------------------------------------------------------------\n\n### Chart A\n\n```{r}\n\n```\n\n\n### Chart B\n\n```{r}\n\n```\n\n### Chart C\n\n```{r}\n\n```\n\n\n"}