#include<bits/stdc++.h>
using namespace std;
#define int long long
const int N=1e6+10,M=1e3+10,P=998244353;
vector<int>G[N];int cut[N],root,siz[N];
int tsp,cnt,dfn[N],low[N];int n,m;
stack<int>stk;bool instk[N];
void tarjan(int x,int f)
{
	dfn[x]=low[x]=++tsp;
	if(G[x].size()==0){return ;}
	stk.push(x);instk[x]=1;
	int child=0;
	for(int y:G[x])if(y!=f)
	{
		if(dfn[y]==0)
		{
			tarjan(y,x);
			low[x]=min(low[x],low[y]);
			if(dfn[x]<=low[y])
			{
				child++;
				if(x!=root || child>1)cut[x]=1;
				for(int z=-1;z!=y;)
				{
					z=stk.top();stk.pop();instk[z]=0;
					siz[z]++;
				};
				siz[x]++; 
			}
		}
		else if(instk[y]==1)low[x]=min(low[x],dfn[y]);
	}
}
int dx[4]={1,0,-1,0},dy[4]={0,1,0,-1};map<pair<int,int>,int>mp;
#define nx x+dx[i]
#define ny y+dy[i]
int v[M][M],a[M][M];
int qpow(int a,int b){int res=1;for(;b;b>>=1,a=a*a%P)if(b&1)res=res*a%P;return res;}
int getid(int x,int y){return (x-1)*m+y;}
void bfs(int xx,int yy)
{
	deque<pair<int,int>>q;q.push_back({xx,yy});
	a[xx][yy]=cnt;
	while(!q.empty())
	{
		int x=q.front().first,y=q.front().second;q.pop_front();
		for(int i=0;i<4;i++)if(nx>0&&nx<=n&&ny>0&&ny<=m&&v[nx][ny]&&!a[nx][ny])
			q.push_back({nx,ny}),a[nx][ny]=cnt;
	}
}
signed main()
{
	cin>>n>>m;int ttsp=0;
	for(int i=1;i<=n;i++)
	{
		string st;cin>>st;
		for(int j=0;j<m;j++)v[i][j+1]=st[j]=='#';
	}
	for(int i=1;i<=n;i++)for(int j=1;j<=m;j++)
		if(v[i][j]&&!a[i][j])
			cnt++,bfs(i,j);
	for(int k=1;k<=n;k++)for(int j=1;j<=m;j++)if(v[k][j])
	{
		int x=k,y=j;
		for(int i=0;i<3;i++)if(v[nx][ny])
		{
			int xx=getid(k,j),yy=getid(nx,ny);
			if(mp[{xx,yy}])continue;
			G[xx].push_back(yy);G[yy].push_back(xx);
			mp[{xx,yy}]=mp[{yy,xx}]=1;
		}
	}
	for(int i=1;i<=n*m;i++)if(!dfn[i])root=i,tarjan(i,0);
	int sum=0,ans=0;
	for(int i=1;i<=n;i++)for(int j=1;j<=m;j++)if(v[i][j])
	{
		int id=getid(i,j);
		ans+=cnt+siz[id]-1;sum++;
	}
	int d=__gcd(sum,ans);sum/=d,ans/=d;ans%=P;
	int anss=ans*qpow(sum,P-2)%P;
	cout<<anss;
	return 0;
}