from collections import defaultdict

H, W = map(int, input().split())
S = [list(input()) for _ in range(H)]

MOD = 998244353

def IDX(h1, w1, h2, w2):
    return w1+h1*W+w2*H*W+h2*W*H*W
def IDXR(n):
    return n%W, n//W%H, n//(H*W)%W, n//(W*H*W)

dp = defaultdict(int)
dp[IDX(1, 0, 0, 1)] = 1
for i in range(H+W-3):
    ndp = defaultdict(int)
    for key in dp.keys():
        w1, h1, w2, h2 = IDXR(key)
        if w1+1 < W and w2+1 < W and S[h1][w1+1] == "." and S[h2][w2+1] == ".":
            ndp[IDX(h1, w1+1, h2, w2+1)] += dp[key]
            ndp[IDX(h1, w1+1, h2, w2+1)] %= MOD
        if h1+1 < H and h2+1 < H and S[h1+1][w1] == "." and S[h2+1][w2] == ".":
            ndp[IDX(h1+1, w1, h2+1, w2)] += dp[key]
            ndp[IDX(h1+1, w1, h2+1, w2)] %= MOD
        if w1+1 < W and h2+1 < H and S[h1][w1+1] == "." and S[h2+1][w2] == "." and ([h1, w1+1] == [H-1, W-1] or [h1, w1+1] != [h2+1, w2]):
            ndp[IDX(h1, w1+1, h2+1, w2)] += dp[key]
            ndp[IDX(h1, w1+1, h2+1, w2)] %= MOD
        if h1+1 < H and w2+1 < W and S[h1+1][w1] == "." and S[h2][w2+1] == "." and ([h1+1, w1] == [H-1, W-1] or [h1+1, w1] != [h2, w2+1]):
            ndp[IDX(h1+1, w1, h2, w2+1)] += dp[key]
            ndp[IDX(h1+1, w1, h2, w2+1)] %= MOD
    dp = ndp

print(dp[IDX(H-1, W-1, H-1, W-1)])