In "All calendars", the color of the device's standard calendar is displayed as it is. If you want to change it, please try the following steps:
How to set
iOS
- Open the standard calendar app
- Tap "Calendar" in the bottom middle
- Tap the mark on the right side of each calendar
- Change color
Android
For the standard calendar app
- Open the standard calendar app
- Tap the upper left corner "-" three lines for settings
- Tap the palette mark on the right side of each calendar in "Calendar"
- Change color
*The location and name may differ depending on the device model.
For Google Calendar App
- Open Google Calendar App
- Tap the "-" three lines in the upper left corner of the menu
- ⚙ Tap Settings
- Tap "Change calendar name and color"
*Colors other than Google Calendar may not be changed