Perfect!
The indentation is wrong!
Please try
[env:esp32-c3-devkitm-1]
platform = espressif32
board = esp32-c3-devkitm-1
framework = arduino
monitor_speed = 115200
build_flags =
-DARDUINO_USB_CDC_ON_BOOT=1
-DARDUINO_USB_MODE=1
When you click the serial port selector you should see something like this:
COM<X> Serial USB-Device (COM<X>) | USB VID:PID=303A:1001 SER=XX:XX:XX:XX:XX:XX
I’ve tried the sketch on my ESP32-C3 super mini using the platformio.ini from above and it works perfect - no issues.