add pandoc theme

[Moelf]

# some title
:::::::::::::: {.columns}
::: {.column width="49%"}
## Julia
```julia
function go_faster(a)
    trace = 0.0
    for i in axes(a, 1)
        trace += tanh(a[i, i])
    end
    return a .+ trace
end
```

:::
::: {.column width="49%"}
## Python (Numba)

```python
@jit(nopython=True)
def go_fast(a):
    trace = 0.0
    for i in range(a.shape[0]):
        trace += np.tanh(a[i, i])
    return a + trace
```

:::
::::::::::::::