Theme Option Reference¶
In this guide, we provide examples of how Streamlit page elements are affected by the various theme config options. For a more high-level overview of Streamlit themes, see the Themes section of the main concepts documentation.
Streamlit themes are defined using regular config options: a theme can be set
via command line flag when starting your app using
streamlit run or by
defining it in the
[theme] section of a
config.toml file. For more
information on setting config options, please refer to the
Streamlit configuration documentation.
The following config options show the default Streamlit Light theme recreated
[theme] section of a
[theme] primaryColor="#F63366" backgroundColor="#FFFFFF" secondaryBackgroundColor="#F0F2F6" textColor="#262730" font="sans serif"
Let’s go through each of these options, providing screenshots to demonstrate what parts of a Streamlit app they affect where needed.
primaryColor defines the accent color most often used throughout a Streamlit
app. A few examples of Streamlit widgets that use
st.text_input (when focused).
Any CSS color can be used as the value for primaryColor and the other color options below. This means that theme colors can be specified in hex or with browser-supported color names like “green”, “yellow”, and “chartreuse”. They can even be defined in the RGB and HSL formats!
Defines the background color used in the main content area of your app.
This color is used where a second background color is needed for added
contrast. Most notably, it is the sidebar’s background color. It is also used
as the border and header color for
st.dataframe, the plot background color
st.plotly_chart, and as the background color for most other interactive
This option controls the text color for most of your Streamlit app.
Selects the font used in your Streamlit app. Valid values are “sans serif”, “serif”, and “monospace”. This option defaults to “sans serif” if unset or invalid.
Note that code blocks are always rendered using the monospace font regardless of the font selected here.