#ifdef NACHIA
#define _GLIBCXX_DEBUG
#else
#define NDEBUG
#endif
#include <iostream>
#include <string>
#include <vector>
#include <algorithm>
using i64 = long long;
using u64 = unsigned long long;
#define rep(i,n) for(i64 i=0; i<i64(n); i++)
const i64 INF = 1001001001001001001;
template<typename A> void chmin(A& l, const A& r){ if(r < l) l = r; }
template<typename A> void chmax(A& l, const A& r){ if(l < r) l = r; }
using namespace std;


#include <utility>

#include <cassert>
namespace nachia{

// ax + by = gcd(a,b)
// return ( x, - )
std::pair<long long, long long> ExtGcd(long long a, long long b){
    long long x = 1, y = 0;
    while(b){
        long long u = a / b;
        std::swap(a-=b*u, b);
        std::swap(x-=y*u, y);
    }
    return std::make_pair(x, a);
}

} // namespace nachia

namespace nachia{

template<unsigned int MOD>
struct StaticModint{
private:
    using u64 = unsigned long long;
    unsigned int x;
public:

    using my_type = StaticModint;
    template< class Elem >
    static Elem safe_mod(Elem x){
        if(x < 0){
            if(0 <= x+MOD) return x + MOD;
            return MOD - ((-(x+MOD)-1) % MOD + 1);
        }
        return x % MOD;
    }

    StaticModint() : x(0){}
    StaticModint(const my_type& a) : x(a.x){}
    StaticModint& operator=(const my_type&) = default;
    template< class Elem >
    StaticModint(Elem v) : x(safe_mod(v)){}
    unsigned int operator*() const { return x; }
    my_type& operator+=(const my_type& r) { auto t = x + r.x; if(t >= MOD) t -= MOD; x = t; return *this; }
    my_type operator+(const my_type& r) const { my_type res = *this; return res += r; }
    my_type& operator-=(const my_type& r) { auto t = x + MOD - r.x; if(t >= MOD) t -= MOD; x = t; return *this; }
    my_type operator-(const my_type& r) const { my_type res = *this; return res -= r; }
    my_type operator-() const noexcept { my_type res = *this; res.x = ((res.x == 0) ? 0 : (MOD - res.x)); return res; }
    my_type& operator*=(const my_type& r){ x = (u64)x * r.x % MOD; return *this; }
    my_type operator*(const my_type& r) const { my_type res = *this; return res *= r; }
    bool operator==(const my_type& r) const { return x == r.x; }
    my_type pow(unsigned long long i) const {
        my_type a = *this, res = 1;
        while(i){ if(i & 1){ res *= a; } a *= a; i >>= 1; }
        return res;
    }
    my_type inv() const { return my_type(ExtGcd(x, MOD).first); }
    unsigned int val() const { return x; }
    int hval() const { return int(x > MOD/2 ? x - MOD : x); }
    static constexpr unsigned int mod() { return MOD; }
    static my_type raw(unsigned int val) { auto res = my_type(); res.x = val; return res; }
    my_type& operator/=(const my_type& r){ return operator*=(r.inv()); }
    my_type operator/(const my_type& r) const { return operator*(r.inv()); }
};

} // namespace nachia
using Modint = nachia::StaticModint<998244353>;

void testcase(){
    i64 H, W; cin >> H >> W;
    vector<string> A(H+1);
    rep(i,H) cin >> A[i];
    rep(i,H) A[i].push_back('#');
    A[H] = string(W+1, '#');
    vector<vector<Modint>> dp(1, vector<Modint>(1,1));
    for(i64 i=1; i<H+W-2; i++){
        i64 p = dp.size();
        vector<vector<Modint>> nx(p+1, vector<Modint>(p+1,0));
        rep(a,p) rep(b,p) if(a<=b){
            nx[a][b] += dp[a][b];
            nx[a+1][b] += dp[a][b];
            nx[a][b+1] += dp[a][b];
            nx[a+1][b+1] += dp[a][b];
        }
        string ref;
        for(i64 x=0; x<W; x++) if(0 <= i-x && i-x < H) ref.push_back(A[i-x][x]);
        i64 q = ref.size();
        //cout << ref << endl;
        i64 off = i < H ? 0 : 1;
        vector<vector<Modint>> nx2(q, vector<Modint>(q,0));
        rep(a,q) rep(b,q) if(a<b && ref[a] == '.' && ref[b] == '.'){
            nx2[a][b] = nx[a+off][b+off];
        }
        swap(dp, nx2);
        //for(auto a : dp){
        //    for(auto b : a) cout << b.val() << " ";
        //    cout << endl;
        //}
    }
    cout << dp[0][1].val() << "\n";
}

int main(){
    ios::sync_with_stdio(false); cin.tie(nullptr);
    rep(f,1) testcase();
    return 0;
}