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#include <iostream>
#include <vector>

using namespace std;

#define T_OCC 0
#define T_POSS 1
#define T_M 2
#define T_L 3
#define T_FREE 4

typedef unsigned long long ULL;
typedef long long LL;
const ULL MOD = 1000000007;

struct P {
	unsigned cols;
	char type;
	char m;
	char l;
};

typedef vector<P> VP;
typedef vector<VP> VVP;
typedef vector<ULL> VULL;

vector<VULL> Newt;

void fillNewt(int N, int K)
{
	Newt = vector<VULL>(N+1, VULL(K+1,0));
	for (auto i = 0; i <= N; i++)
	{
		Newt[i][0] = 1;
		for (auto j = 1; j < K && j <= i; j++)
		{
			Newt[i][j] = (Newt[i-1][j-1] + Newt[i-1][j]) % MOD;
		}
	}
}

ULL newt(int n, int k)
{
	if (n < k) return 0;
	return Newt[n][k];
}

int main()
{
	ios_base::sync_with_stdio(false);

	int N, K;
	cin >> N >> K;

	VVP v(N, VP(N, P()));

	for (auto i = 0; i < N; i++)
	{
		char s[N+3];
		cin >> s;
		for (auto j = 0; j < N; j++)
		{
			v[i][j].type = s[j]=='#' ? T_OCC : T_FREE;
		}
	}
	auto validxy = [&N](int x, int y) { return x>=0&&x<N&&y>=0&&y<N; };
	auto applyNeighbours = [&v,&validxy](int x, int y, void (*fun)(P &p)) {
		if (validxy(x-1,y)) fun(v[x-1][y]);
		if (validxy(x+1,y)) fun(v[x+1][y]);
		if (validxy(x,y-1)) fun(v[x][y-1]);
		if (validxy(x,y+1)) fun(v[x][y+1]);
	};
	auto setPossIfFree = [](P &p) { if (p.type == T_FREE) p.type = T_POSS; };
	// find first possibilities
	for (auto i = 0; i < N; i++)
	{
		for (auto j = 0; j < N; j++)
		{
			if (v[i][j].type == T_OCC)
				applyNeighbours(i,j, setPossIfFree);
		}
	}
	// find ms
	ULL n = 0;
	static int m = 0;
	auto setMsIfFree = [](P &p) {
	   if (p.type == T_FREE) {
		   p.type = T_M;
		   p.cols = 1;
		   m++;
	   } else if (p.type == T_M) p.cols++;
	};
	for (auto i = 0; i < N; i++)
	{
		for (auto j = 0; j < N; j++)
		{
			if (v[i][j].type == T_POSS)
			{
				n++;
				applyNeighbours(i,j, setMsIfFree);
			}
		}
	}
	//find ls
	auto setLsIfFree = [](P &p) { if (p.type == T_FREE) p.type = T_L; };
	for (auto i = 0; i < N; i++)
	{
		for (auto j = 0; j < N; j++)
		{
			if (v[i][j].type == T_M)
				applyNeighbours(i,j, setLsIfFree);
		}
	}

	vector<int> poss;
	poss.reserve(n);
	vector<int> ms;
	ms.reserve(m);
	for (auto i = 0; i < N; i++)
	{
		for (auto j = 0; j < N; j++)
		{
			if (v[i][j].type == T_POSS)
			{
				poss.push_back(i*N+j);
			} else if (v[i][j].type == T_M)
			{
				ms.push_back(i*N+j);
			}
		}
	}

	fillNewt(n, K+1);
	if (K == 1)
	{
		cout << newt(n, K) << endl;
		return 0;
	}
	
	auto checkType = [&v, &validxy](int x, int y, char type) {
		return (validxy(x, y) && v[x][y].type == type) ? 1 : 0;
	};
	// count ms
	ULL msum = 0;
	for (auto &pi : poss)
	{
		int i = pi/N;
		int j = pi%N;
		char c = 0;
		c += checkType(i-1, j, T_M);
		c += checkType(i+1, j, T_M);
		c += checkType(i, j-1, T_M);
		c += checkType(i, j+1, T_M);
		v[i][j].m = c;
		msum += c;
	}

	if (K == 2)
	{
		cout << (newt(n, K) + msum) % MOD << endl;
		return 0;
	}

	ULL newtksum = 0;

	int idx = n;
	for (auto it = poss.rbegin(); it != poss.rend(); ++it)
	{
		P &p = v[*it/N][*it%N];
		newtksum = (newtksum + newt(p.m, K-1)) % MOD;
		idx--;
	}

	ULL lsum = 0;
	ULL cols_cnt = 0;
	for (auto &pi: ms)
	{
		int i = pi/N;
		int j = pi%N;
		P &p = v[i][j];
		if (p.cols > 1) cols_cnt++;

		char c = 0;
		c += checkType(i-1, j, T_L);
		c += checkType(i+1, j, T_L);
		c += checkType(i, j-1, T_L);
		c += checkType(i, j+1, T_L);
		p.l = c;
	}
	for (auto &pi: poss)
	{
		int i = pi/N;
		int j = pi%N;
		P &p = v[i][j];
		if (checkType(i-1, j, T_M)) p.l += v[i-1][j].l; 
		if (checkType(i+1, j, T_M)) p.l += v[i+1][j].l; 
		if (checkType(i, j-1, T_M)) p.l += v[i][j-1].l; 
		if (checkType(i, j+1, T_M)) p.l += v[i][j+1].l; 
		lsum = (lsum + p.l) % MOD;
	}

	ULL res = newt(n, K);
	res = (res + msum * newt(n-1, K-2) - cols_cnt * newt(n-K+2,K-3)) % MOD;
	res = (res + newtksum) % MOD;
	if (K == 3)
	{
		res = (res + lsum) % MOD;
		cout << res << endl;
		return 0;
	}

	cout << res << endl;

	return 0;
}