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#include <algorithm>
#include <iostream>
#include <vector>
#include <cassert>
#include <queue>
#include <set>

constexpr int MAX_SIZE = 3024;
constexpr int64_t MOD = 1e9+7;

struct Point {
	int x, y;
};

struct TrieNode {
	int chr[2];
	TrieNode() { chr[0] = chr[1] = -1; }
};

int width, moves;
char board[MAX_SIZE][MAX_SIZE];

int64_t counts[4], ways[4];
int64_t waysFor[MAX_SIZE][MAX_SIZE];
int64_t toAdj[MAX_SIZE][MAX_SIZE];
int64_t toNextChooseTwo[4], toPrevWithTwo[4];

std::vector<TrieNode> nodes;
int64_t bruteRet;

int64_t modInv(int64_t a, int64_t b) {
	int64_t u = 1, v = 0, x = 0, y = 1;
	int64_t m = b;

	while (a > 0) {
		int64_t q = b / a, r = b % a;
		int64_t m = x - u*q, n = y - v*q;
		b = a; a = r; x = u; y = v; u = m; v = n;
	}
	return (b == 1 ? (x < 0 ? x+m : x) : 0);
}

template<typename T>
void eachNeigh(int x, int y, T func) {
	if (x > 0)       { func(x-1, y); }
	if (x+1 < width) { func(x+1, y); }
	if (y > 0)       { func(x, y-1); }
	if (y+1 < width) { func(x, y+1); }
}

void insertOpt() {
	int cur = 0;
	bool add = false;

	for (int y = 0; y < width; y++) {
		for (int x = 0; x < width; x++) {
			int dir = (board[x][y] == 0 ? 1 : 0);

			if (nodes[cur].chr[dir] < 0) {
				nodes[cur].chr[dir] = nodes.size();
				nodes.emplace_back();
				add = true;
			}

			cur = nodes[cur].chr[dir];
		}
	}
	bruteRet += (add ? 1 : 0);
}

void bruteSolve(int moves) {
	for (int x = 0; x < width; x++) {
		for (int y = 0; y < width; y++) {
			if (board[x][y] == 0) {
				continue;
			}

			bool ok = false;
			if (x > 0)       { ok |= (board[x-1][y] == 0); }
			if (x+1 < width) { ok |= (board[x+1][y] == 0); }
			if (y > 0)       { ok |= (board[x][y-1] == 0); }
			if (y+1 < width) { ok |= (board[x][y+1] == 0); }

			if (ok) {
				board[x][y] = 0;
				if (moves == 1) {
					insertOpt();
				} else {
					bruteSolve(moves-1);
				}
				board[x][y] = 100;
			}
		}
	}
}

int main() {
	std::ios::sync_with_stdio(false); std::cin.tie(0);
	std::cin >> width >> moves;

	for (int y = 0; y < width; y++) {
		std::string tmp; std::cin >> tmp;
		for (int x = 0; x < width; x++) {
			board[y][x] = (tmp[x] == '#' ? 0 : 100);
		}
	}

	if (moves >= 4) {
		nodes.emplace_back();
		bruteSolve(moves);
		std::cout << bruteRet % MOD << std::endl;
		return 0;
	}

	std::queue<Point> que;
	for (int x = 0; x < width; x++) {
		for (int y = 0; y < width; y++) {
			if (board[x][y] == 0) {
				que.push({ x, y });
			}
		}
	}

	// Compute

	while (!que.empty()) {
		Point elem = que.front();
		que.pop();

		int dist = board[elem.x][elem.y];
		int toPrev = 0, toNext = 0;

		eachNeigh(elem.x, elem.y, [&](int x, int y) {
			if (board[x][y] >= dist+1) {
				if (dist == 0) {
					waysFor[x][y] = 1;
				} else {
					waysFor[x][y] = (waysFor[x][y] + waysFor[elem.x][elem.y]) % MOD;
				}

				ways[dist+1] = (ways[dist+1] + waysFor[elem.x][elem.y]) % MOD;
				toNext++;
			}

			if (board[x][y] == dist-1) {
				toPrev++;
			}
			if (board[x][y] == dist) {
				toAdj[elem.x][elem.y]++;
			}

			if (board[x][y] > dist+1) {
				board[x][y] = dist+1;
				if (dist+1 <= moves) {
					que.push({ x, y });
				}
			}
		});

		toNextChooseTwo[dist] = (toNextChooseTwo[dist] + toNext*(toNext-1)/2) % MOD;
		toPrevWithTwo[dist] = (toPrevWithTwo[dist] + toPrev*(counts[dist-1] - toPrev) + toPrev*(toPrev-1)/2) % MOD;

		counts[dist]++;
	}

	// Sum

	int64_t ret = 0;

	if (moves == 1) {
		ret = counts[1] % MOD;
	} else if (moves == 2) {
		ret = (counts[1]*(counts[1]-1)/2 + ways[2]) % MOD;
	} else if (moves == 3) {
		ret = (((((counts[1]*(counts[1]-1)) % MOD) * (counts[1]-2)) % MOD) * modInv(6, MOD)) % MOD;
		ret = (ret + ways[3] + toNextChooseTwo[1] + toPrevWithTwo[2]) % MOD;

		for (int x = 0; x < width; x++) {
			for (int y = 0; y < width; y++) {
				if (board[x][y] != 1) {
					continue;
				}

				eachNeigh(x, y, [&](int x2, int y2) {
					if (board[x2][y2] == 2) {
						ret += toAdj[x2][y2];
					}
				});
			}
		}
		ret = ret % MOD;
	}

	std::cout << ret << std::endl;
	return 0;
}