#include <stdio.h>

typedef struct tree {
  struct tree *p;
} tree;

tree *get_root (tree *t) {
  if (t == NULL || t->p == NULL) {
    return t;
  }
  
  t->p = get_root(t->p);
  return t->p;
}

long long power_mod (long long a, long long b, long long mod_num) {
  long long ans = 1LL;
  
  if (b > 0LL) {
    ans = power_mod(a, b/2LL, mod_num);
    ans = (ans * ans) % mod_num;
    if (b%2LL == 1LL) {
      ans = (ans * a) % mod_num;
    }
  }
  
  return ans;
}

int main () {
  int n = 0;
  int m = 0;
  char s[500][501] = {};
  
  int res = 0;
  
  int ans = 0;
  long long mod_num = 998244353LL;
  
  tree t[500][500] = {};
  
  res = scanf("%d", &n);
  res = scanf("%d", &m);
  for (int i = 0; i < n; i++) {
    res = scanf("%s", s[i]);
  }
  
  for (int i = 0; i < n; i++) {
    for (int j = 0; j < m; j++) {
      if (s[i][j] == '#') {
        ans++;
        if (i <= 0 || s[i-1][j] != '#') {
          ans++;
        }
        if (j <= 0 || s[i][j-1] != '#') {
          ans++;
        }
      }
      t[i][j].p = NULL;
    }
  }
  
  for (int i = 0; i < n-1; i++) {
    for (int j = 0; j < m; j++) {
      if (s[i][j] == '#' && s[i+1][j] == '#') {
        tree *rt1 = get_root(t[i]+j);
        tree *rt2 = get_root(t[i+1]+j);
        if (rt1 != rt2) {
          rt2->p = rt1;
        }
      }
    }
  }
  for (int i = 0; i < n; i++) {
    for (int j = 0; j < m-1; j++) {
      if (s[i][j] == '#' && s[i][j+1] == '#') {
        tree *rt1 = get_root(t[i]+j);
        tree *rt2 = get_root(t[i]+(j+1));
        if (rt1 != rt2) {
          rt2->p = rt1;
        }
      }
    }
  }
  
  for (int i = 0; i < n; i++) {
    for (int j = 0; j < m; j++) {
      if (s[i][j] == '#' && t[i][j].p == NULL) {
        ans--;
      }
    }
  }
  
  printf("%lld\n", power_mod(2LL, (long long)ans, mod_num));
  return 0;
}