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#include <cstdio>
#include <string>
#include <vector>
using namespace std;

int n, k;
char board[3007][3007];
int possible_moves[3007][3007];
bool used[3007][3007];
int sum, number_of_moves;

const int MOD = 1e9 + 7;

//inline void printBoard() {
//    printf("\n");
//    for (int i = 1; i <= n; ++i) {
//        for (int j = 1; j <= n; ++j)
//            printf("%c", board[i][j]);
//        printf("\n");
//    }
//    printf("\n");
//}

inline void makePossible(int a, int b, bool if_possible) {
    if (board[a][b] == '.') {
        if (if_possible) {
            if (possible_moves[a][b] == 0) {
                ++number_of_moves;
            }
            ++possible_moves[a][b];
        } else {
            --possible_moves[a][b];
            if (possible_moves[a][b] == 0) {
                --number_of_moves;
            }
        }
    }
}

inline void makeAdjacentPossible(int a, int b, bool if_possible) {
    makePossible(a - 1, b, if_possible);
    makePossible(a + 1, b, if_possible);
    makePossible(a, b - 1, if_possible);
    makePossible(a, b + 1, if_possible);
}

inline void markAsUsed(int a, int b, bool if_used) {
    if (if_used) {
        used[a][b] = true;
        --number_of_moves;
    } else {
        used[a][b] = false;
        ++number_of_moves;
    }
}

inline void findPossibleMoves() {
    for (int i = 1; i <= n; ++i) {
        for (int j = 1; j <= n; ++j) {
            if (board[i][j] == '#')
                makeAdjacentPossible(i, j, true);
        }
    }
}

void placeTile(int tiles, int a, int b) {
    if (tiles == k - 1) {
        board[a][b] = '#';
        --number_of_moves;
        makeAdjacentPossible(a, b, true);
        //printBoard();
        sum += number_of_moves;
        sum %= MOD;

        board[a][b] = '.';
        ++number_of_moves;
        makeAdjacentPossible(a, b, false);
    } else {
        board[a][b] = '#';
        --number_of_moves;
        makeAdjacentPossible(a, b, true);

        vector<pair<int, int>> usedPositions;
        for (int i = 1; i <= n; ++i) {
            for (int j = 1; j <= n; ++j) {
                if (possible_moves[i][j] > 0 && board[i][j] == '.' && !used[i][j]) {
                    placeTile(tiles + 1, i, j);
                    markAsUsed(i, j, true);
                    usedPositions.emplace_back(i, j);
                }
            }
        }
        board[a][b] = '.';
        ++number_of_moves;
        makeAdjacentPossible(a, b, false);
        for (int i = 0; i < (int)usedPositions.size(); ++i) {
            pair<int, int> p = usedPositions[i];
            markAsUsed(p.first, p.second, false);
        }
    }
}

int main() {
    scanf("%d%d", &n, &k);
    for (int i = 1; i <= n; ++i) {
        scanf("%s", board[i] + 1);
        board[i][0] = '*';
        board[i][n + 1] = '*';
    }
    for (int i = 0; i <= n + 1; ++i) {
        board[0][i] = '*';
        board[n + 1][i] = '*';
    }

    findPossibleMoves();
    if (k > 1) {
        for (int i = 1; i <= n; ++i) {
            for (int j = 1; j <= n; ++j) {
                if (possible_moves[i][j] > 0 && board[i][j] == '.') {
                    placeTile(1, i, j);
                    markAsUsed(i, j, true);
                }
            }
        }
        printf("%d", sum);
    } else
        printf("%d", number_of_moves);
    return 0;
}