def prop(i, j):
    if ok[i][j]:
        return

    st = [(i, j)]
    ok[i][j] = True
    d = [(x, y) for x in range(-1, 2) for y in range(-1, 2)]
    while st:
        i, j = st.pop()
        for di, dj in d:
            if not (0 <= i + di < n and 0 <= j + dj < m):
                continue
            if s[i + di][j + dj] == "#":
                continue
            if ok[i + di][j + dj]:
                continue
            ok[i + di][j + dj] = True
            st.append((i + di, j + dj))


n, m = map(int, input().split())
s = [input() for i in range(n)]
ok = [[False] * m for i in range(n)]
for i in range(n):
    if s[i][0] == ".":
        prop(i, 0)
    if s[i][-1] == ".":
        prop(i, m - 1)

for j in range(m):
    if s[0][j] == ".":
        prop(0, j)
    if s[-1][j] == ".":
        prop(n - 1, j)


cnt = 0
for i in range(n):
    for j in range(m):
        if s[i][j] == ".":
            if not ok[i][j]:
                cnt -= 1
                prop(i, j)
        else:
            cnt += 2
            if i == n - 1 or j == m - 1:
                continue
            for di, dj in [(0, 0), (0, 1), (1, 0), (1, 1)]:
                if s[i + di][j + dj] == ".":
                    break
            else:
                cnt -= 1

print(pow(2, cnt, 998244353))