#ifndef ONLINE_JUDGE
#define _GLIBCXX_DEBUG
#endif
#include <bits/stdc++.h>
#include <cassert>
#include <atcoder/all>
using namespace std;
using namespace atcoder;
using ll = long long;
using mint = modint998244353;
//using mint = modint1000000007;
#define rep(i, n) for (int i = 0; i < (int)(n); i++)
#define repu(i, s, t) for (int i = (int)(s); i < (int)(t); i++)
#define repd(i, s, t) for (int i = (int)(s)-1; i >= (int)(t); i--)
#define all(v) v.begin(), v.end()
void _u() { cerr << endl; } template <class H, class... T> void _u(H&& h, T&&... t) { cerr << h << ", "; _u(move(t)...); }
#define U(...) { cerr << #__VA_ARGS__ << ": "; _u(__VA_ARGS__); }
template<typename T> bool chmax(T &a, const T b) { if(a >= b) return false; a = b; return true; }
template<typename T> bool chmin(T &a, const T b) { if(a <= b) return false; a = b; return true; }
template<typename T> istream& operator>>(istream &in, vector<T> &a) { for(T &x: a) in >> x; return in; }
template<typename T> ostream& operator<<(ostream &out, const vector<T> &a) { for(const T &x: a) out << x << ' '; return out; }
const int di[] = {1, 0, -1, 0, 1, 1, -1, -1, 0};
const int dj[] = {0, 1, 0, -1, -1, 1, 1, -1, 0};


int main() {
    int h, w;
    cin >> h >> w;
    vector<string> s(h);
    cin >> s;
    while(s.size() < s[0].size()) {
        s.emplace_back(w, '#');
    }
    while(s.size() > s[0].size()) {
        rep(i, h) s[i].push_back('#');
    }

    vector<vector<mint>> dp(1, vector<mint>(1, 1));
    rep(k, h+w-3) {
        int n = dp.size();
        if(k < max(h, w)-1) {
            n++;
            vector<vector<mint>> pre(n, vector<mint>(n));
            swap(pre, dp);
            rep(i, n-1) rep(j, n-1) {
                if(i < j) dp[i][j] += pre[i][j];
                if(i < j+1) dp[i][j+1] += pre[i][j];
                if(i+1 < j) dp[i+1][j] += pre[i][j];
                if(i+1 < j+1) dp[i+1][j+1] += pre[i][j];
            }
            rep(i, n) rep(j, n) if(s[n-i-1][i] == '#' || s[n-j-1][j] == '#') dp[i][j] = 0;
        } else {
            n--;
            vector<vector<mint>> pre(n, vector<mint>(n));
            swap(pre, dp);
            rep(i, n) rep(j, n) if(i < j) {
                dp[i][j] += pre[i][j];
                dp[i][j] += pre[i][j+1];
                dp[i][j] += pre[i+1][j];
                dp[i][j] += pre[i+1][j+1];
            }
            int m = max(h, w);
            rep(i, n) rep(j, n) if(s[m-i-1][k-m+2+i] == '#' || s[m-j-1][k-m+2+j] == '#') dp[i][j] = 0;
        }
    }
    mint ans;
    if(h > w) ans = dp[0][1];
    else ans = dp.end()[-2].end()[-1];
    cout << ans.val() << endl;
    return 0;
}