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#include <iostream>
#include <cstdio>
#include <vector>
#include <queue>
using namespace std;
const int N=3005;
const long long MOD=1e9+7;
int n, k, odl[N][N];
char c[N];
bool inv[N][N];
queue< pair<int,int> > q;
vector< pair<int,int> > v[4];
long long ans, ilo[N][N];
void check(int x, int y, int odlo, long long il)
{
        if(!inv[x][y])
        {
                inv[x][y]=1;
                odl[x][y]=odlo;
                ilo[x][y]=il;
                v[odlo].push_back(make_pair(x,y));
                if(odlo!=k) q.push(make_pair(x,y));
        }
        else if(odlo!=1 && odlo==odl[x][y]) ilo[x][y]+=il;
}
void bfs()
{
        while(!q.empty())
        {
                int x=q.front().first;
                int y=q.front().second;
                int odlo=odl[x][y]+1;
                long long il=ilo[x][y];
                q.pop();
                check(x+1,y,odlo,il);
                check(x-1,y,odlo,il);
                check(x,y-1,odlo,il);
                check(x,y+1,odlo,il);
        }
}
long long pot(long long a, long long p)
{
        if(p==0) return 1;
        long long w=pot(a,p/2);
        w=w*w%MOD;
        if(p%2==0) return w;
        return w*a%MOD;
}
long long ilew(int x, int y)
{
        long long ans=0;
        if(odl[x-1][y]>odl[x][y]) ans++;
        if(odl[x][y-1]>odl[x][y]) ans++;
        if(odl[x][y+1]>odl[x][y]) ans++;
        if(odl[x+1][y]>odl[x][y]) ans++;
        return ans;
}
int main()
{
        scanf("%d%d", &n, &k);
        for(int i=1;i<=n;i++)
  {
                scanf("%s", &c);
                for(int j=0;j<n;j++) if(c[j]=='#')
                {
                        inv[i][j+1]=1;
                        ilo[i][j+1]=1;
                        q.push(make_pair(i,j+1));
                }
        }
        for(int i=1;i<=n;i++)
        {
                inv[0][i]=1;
                inv[n+1][i]=1;
                inv[i][0]=1;
                inv[i][n+1]=1;
        }
        bfs();
        if(k==1) ans=(long long)(v[1].size())%MOD;
        if(k==2)
        {
                long long tmp=v[1].size();
                ans=tmp*(tmp-1);
                ans/=2;
                ans%=MOD;
                for(int i=0;i<v[2].size();i++)
                {
                        int x=v[2][i].first;
                        int y=v[2][i].second;
                        ans+=ilo[x][y];
                        ans%=MOD;
                }
        }
        if(k==3)
        {
                long long ilo1=v[1].size(), ilo2=v[2].size(), ilo3=v[3].size();
                for(int i=0;i<ilo3;i++)
                {
                        int x=v[3].size();
                        int y=v[3].size();
                        ans+=ilo[x][y];
                        ans%=MOD;
                }
                for(int i=0;i<ilo1;i++)
                {
                        int x=v[1][i].first;
                        int y=v[1][i].second;
                        long long d=ilew(x,y);
                        ans+=(d*(d-1))/2;
                        ans%=MOD;
                }
                for(int i=0;i<ilo2;i++)
                {
                        int x=v[2][i].first;
                        int y=v[2][i].second;
                        ans+=(ilo1-ilo[x][y])*ilo[x][y];
                        ans%=MOD;
                        ans+=((ilo[x][y]-1)*(ilo[x][y]))/2;
                        ans%=MOD;
                }
                long long tmp=ilo1*(ilo1-1);
                tmp%=MOD;
 tmp*=(ilo1-2);
                tmp%=MOD;
                tmp*=pot(6,MOD-2);
                tmp%=MOD;
                ans+=tmp;
                ans%=MOD;
        }
        if(k==4)
        {
                long long ilo1=v[1].size(), ilo2=v[2].size(), ilo3=v[3].size();
                long long ilo4=v[4].size();
                for(int i=0;i<ilo4;i++)
                {
                        int x=v[4][i].first;
                        int y=v[4][i].second;
                        ans+=ilo[x][y]; //1
                        ans%=MOD;
                }
                long long tmp=ilo4*(ilo4-1);
                tmp%=MOD;
                tmp*=(ilo4-2);
                tmp%=MOD;
                tmp*=(ilo4-3);
                tmp%=MOD;
                ans+=tmp;
                ans%=MOD;
                for(int i=0;i<ilo2;i++)
                {
                        int x=v[2][i].first;
                        int y=v[2][i].second;
                        long long d=ilew(x,y);
                        ans+=((d*(d-1))/2)*ilo[x][y];
                        ans%=MOD;
                        long long tmp=(ilo1-ilo[x][y])*(ilo1-ilo[x][y]-1);
                        tmp%=MOD;
                        tmp*=ilo[x][y];
                        tmp%=MOD;
                        tmp+=(ilo[x][y]*(ilo[x][y]-1)*(ilo[x][y]-2))/6;
                        tmp%=MOD;
                        ans+=tmp;
                        ans%=MOD;
                        tmp=d*ilo[x][y]*(ilo1-ilo[x][y])+ilo[x][y]*(ilo[x][y]-1)*d*(d-1); //5
                        tmp%=MOD;
                        ans+=tmp;
                        ans%=MOD;
                }
                for(int i=0;i<ilo1;i++)
                {
                        int x=v[1][i].first;
                        int y=v[1][i].second;
                        long long d=ilew(x,y);
                        if(d==3) ans++;
                        ans%=MOD;
                }
                for(int i=0;i<ilo3;i++)
                {
                        int x=v[3][i].first;
                        int y=v[3][i].second;

                }
        }
  printf("%lld", ans);
        return 0;
}