Can't mix specification with fmt library

With fmt library (or std::format) I can do formatting like in the example below

#include <fmt/core.h>

int main() {
    double x = 2.0/3.0;
    fmt::print("{:*^30}\n", x); //print ******0.6666666666666666******
    fmt::print("{:+.3e}\n", x); //print +6.667e-01
 }

In the above code, I can:

• Use the first formatting to center x and pad with *.
• Use the second formatting to format x in scientific notation with 3 decimal places and a +.

How can I combine both of these to get this?

**********+6.667e-01**********