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#include <cstdio>
#include <algorithm>
#include <vector>
#include <cmath>
#include <iostream>
#include <ctime>

using namespace std;

struct tuple4 {
    int a, b, c, d;   
    tuple4(int a, int b, int c, int d) : a(a), b(b), c(c), d(d) {}
};

const int MAX = 7; // Max windows size
const int SET = 9; // number of neighbours representing initially occupied field
const int MODULO = 1000000007;

void printTime() {
    static int start = clock();
    static int i = 0;
    clock_t end = clock();
    if (i > 0) {
        double elapsed_secs = double(end - start) / CLOCKS_PER_SEC;
        start = end;
        cout << i << " Time: " << elapsed_secs << endl;
    }
    i++;
}

long long combinations(const int posibleChoicesNumber, const int choose) {
    unsigned long long mul = 1;
    int div = 1;
    if (choose > posibleChoicesNumber) {
        return 0;
    }
    for(int i = 0; i < choose; i++) {
        mul = mul * (posibleChoicesNumber -i);
        div = div * (i+1);
    }
    //cout << mul << ":" << div << endl;
    return (mul/div)%MODULO;
}

int readField(vector< vector<bool> > &field, const int n) {
    int lastNeigh[2][3000];
    char x;
    int fieldsWithNeighbours = 0;
    for (int i = 0; i < n; i++) {
        int lastRowIdx = 0;
        if(i>0) {
            lastRowIdx = (i-1) % 2;
        }
        int rowIdx = i % 2;
        for (int j = 0; j < n; j++) {
            int neigh = 0;
            cin >> x;
            if ('#' == x) {
                neigh = SET;
                //cout << '#';
                field[i][j] = true;
                if (i>0) {
                    if (lastNeigh[lastRowIdx][j] == 0) {
                        fieldsWithNeighbours++;
                    }
                    if (lastNeigh[lastRowIdx][j] != SET) {
                        lastNeigh[lastRowIdx][j] += 1;
                    }
                }
                if (j>0) {
                    if (lastNeigh[rowIdx][j-1] == 0) {
                        fieldsWithNeighbours++;
                    }
                    if (lastNeigh[rowIdx][j-1] != SET) {
                        lastNeigh[rowIdx][j-1] += 1;
                    }
                }
            } else {
                //cout << '.';
                field[i][j] = false;
            }
            if (neigh != SET && i>0 && field[i-1][j]) {
                neigh += 1;
            }
            if (neigh != SET && j>0 && field[i][j-1]) {
                neigh += 1;
            }
            if (neigh != SET && neigh > 0 && !field[i][j]) {
                fieldsWithNeighbours++;
            }
            lastNeigh[rowIdx][j] = neigh;
        }
        //cout << endl;
    }
    return fieldsWithNeighbours;
}

int sumDiagonals(int diagonalSum[5], int diagonal, int k) {
    if (diagonal == 2 && k >= 2) {
        return diagonalSum[2];
    } else if (diagonal == 3 && k >= 3) {
        return max(diagonalSum[2] - 1 + diagonalSum[3], 0);
    } else if (diagonal == 4 && k >= 4) {
        return max(diagonalSum[2] -1 + diagonalSum[3] - 1 + diagonalSum[4], 0);
    } else {
        return 0;
    }
}

int getSumOfNeighbours(vector< vector<bool> > &field, vector< vector<int> > &lastNeigh, const int n, const int k, const int row, const int column) {
    int sum = 0;
    if (row < 0 || row >= n || column < 0 || column >= n || lastNeigh[(row) % (2*k+1)][column] != 0 || field[row][column] || k < 2) {
        return 0;
    }
    if (row - 1 >= 0 && lastNeigh[(row-1) % (2*k+1)][column] != SET && lastNeigh[(row-1) % (2*k+1)][column] != 0) {
        sum += 1;
        //cout << "(" << row-1 << "," << column << "#" << sum <<  ")";
    }
    if (row + 1 < n && lastNeigh[(row+1) % (2*k+1)][column] != SET && lastNeigh[(row+1) % (2*k+1)][column] != 0) {
        sum += 1;
        //cout << "(" << row+1 << "," << column << "#" << sum << ")";
    }
    if (column - 1 >= 0 && lastNeigh[(row) % (2*k+1)][column-1] != SET && lastNeigh[(row) % (2*k+1)][column-1] != 0) {
        sum += 1;
        //cout << "(" << row << "," << column-1 << "#" << sum << ")";
    }
    if (column + 1 < n && lastNeigh[(row) % (2*k+1)][column+1] != SET && lastNeigh[(row) % (2*k+1)][column+1] != 0) {
        sum += 1;
        //cout << "(" << row << "," << column+1 << "#" << sum << ")";
    }
    return sum;
}

int getSumOfZeroNeighbours(vector< vector<bool> > &field, vector< vector<int> > &lastNeigh, const int n, const int k, const int row, const int column) {
    int sum = 0;
    if (row < 0 || row >= n || column < 0 || column >= n || field[row][column]) {
        return 0;
    }
    if (row - 1 >= 0 && lastNeigh[(row-1) % (2*k+1)][column] == 0 && !field[row-1][column]) {
        sum += 1;
        //cout << "(" << row-1 << "," << column << "#" << sum <<  ")";
    }
    if (row + 1 < n && lastNeigh[(row+1) % (2*k+1)][column] == 0 && !field[row+1][column]) {
        sum += 1;
        //cout << "(" << row+1 << "," << column << "#" << sum << ")";
    }
    if (column - 1 >= 0 && lastNeigh[(row) % (2*k+1)][column-1] == 0  && !field[row][column-1]) {
        sum += 1;
        //cout << "(" << row << "," << column-1 << "#" << sum << ")";
    }
    if (column + 1 < n && lastNeigh[(row) % (2*k+1)][column+1] == 0  && !field[row][column+1]) {
        sum += 1;
        //cout << "(" << row << "," << column+1 << "#" << sum << ")";
    }
    return sum;
}

int getSumOfNeighZeroNeighbours(vector< vector<bool> > &field, vector< vector<int> > &lastNeigh, const int n, const int k, const int row, const int column) {
    int sum = 0;
    if (row < 0 || row >= n || column < 0 || column >= n) {
        return 0;
    }
    if (row - 1 >= 0 && lastNeigh[(row-1) % (2*k+1)][column] == 0 && !field[row-1][column]) {
        sum += getSumOfZeroNeighbours(field, lastNeigh, n, k, row-1, column);
        //cout << "(" << row-1 << "," << column << "#" << sum <<  ")";
    }
    if (row + 1 < n && lastNeigh[(row+1) % (2*k+1)][column] == 0 && !field[row+1][column]) {
        sum += getSumOfZeroNeighbours(field, lastNeigh, n, k, row+1, column);
        //cout << "(" << row+1 << "," << column << "#" << sum << ")";
    }
    if (column - 1 >= 0 && lastNeigh[(row) % (2*k+1)][column-1] == 0  && !field[row][column-1]) {
        sum += getSumOfZeroNeighbours(field, lastNeigh, n, k, row, column-1);
        //cout << "(" << row << "," << column-1 << "#" << sum << ")";
    }
    if (column + 1 < n && lastNeigh[(row) % (2*k+1)][column+1] == 0  && !field[row][column+1]) {
        sum += getSumOfZeroNeighbours(field, lastNeigh, n, k, row, column+1);
        //cout << "(" << row << "," << column+1 << "#" << sum << ")";
    }
    return sum;
}

long long getSum(int diagonalSum[5], const int k, const int fieldsWithNeighbours) {
    int additional = (k >= 3) ? max(diagonalSum[1]-diagonalSum[2], 0) : 0;
    //cout << "A:" << additional << "D:" << diagonalSum[1] << endl;
    //long long sum = diagonalSum[1]*(combinations(fieldsWithNeighbours-diagonalSum[1],k-2) + sumDiagonals(diagonalSum, 3, k)*combinations(fieldsWithNeighbours-diagonalSum[1],k-3) + sumDiagonals(diagonalSum, 3, k)*sumDiagonals(diagonalSum, 4, k)) + additional;
    long long sum = diagonalSum[1]*1;
    if (additional > 0) {
         //cout << "#" << diagonalSum[1] << ":" << diagonalSum[2] << ":" << diagonalSum[3] << ":" << diagonalSum[4] << fieldsWithNeighbours << " - " << k << "#";
    }
    if (k == 3) {
       sum = sum * (combinations(fieldsWithNeighbours-diagonalSum[1],1) + additional + sumDiagonals(diagonalSum, 3, k));
    }
    if (k == 4) {
       sum = sum * (combinations(fieldsWithNeighbours-diagonalSum[1], 2) + sumDiagonals(diagonalSum, 3, k)*combinations(fieldsWithNeighbours-1,1) + sumDiagonals(diagonalSum, 3, k)*sumDiagonals(diagonalSum, 4, k)) + max(diagonalSum[1], 0);
    }
    if (sum > 0) {
        //cout << combinations(fieldsWithNeighbours-diagonalSum[1],k-2) << " " << sumDiagonals(diagonalSum, 3, k)*combinations(fieldsWithNeighbours-diagonalSum[1],k-3) << " " << sumDiagonals(diagonalSum, 3, k)*sumDiagonals(diagonalSum, 4, k) << endl;
    }
    return sum;
}

long long checkCellAdditionalSolutions(vector< vector<bool> > &field, vector< vector<int> > &lastNeigh, const int n, const int k, const int fieldsWithNeighbours, const int row, const int column) {
    long long additionalSol = 0;
    int additionalPathToAlreadyAnalyzed = 0;
    int diagonalSum[5];
    diagonalSum[1] = 0; // first
    diagonalSum[2] = 0; // second
    diagonalSum[3] = 0; // third 
    diagonalSum[4] = 0; //fourth
    int initRowIdx = row % (2*k+1);
    //cout << "(" << row  << "," << column << ")" << " # " << lastNeigh[initRowIdx][column];
    if (lastNeigh[initRowIdx][column] == 0 || lastNeigh[initRowIdx][column] == SET) {
       //cout << endl;
       return 0;
    }
    int top = (k>=2) ? getSumOfNeighbours(field, lastNeigh, n, k, row-1, column) : 0;
    int bottom = (k>=2) ? getSumOfNeighbours(field, lastNeigh, n, k, row+1, column) : 0;
    int left = (k>=2) ? getSumOfNeighbours(field, lastNeigh, n, k, row, column-1) : 0;
    int right = (k>=2) ? getSumOfNeighbours(field, lastNeigh, n, k, row, column+1) : 0;
    int topZero = (k>=3) ? getSumOfZeroNeighbours(field, lastNeigh, n, k, row-1, column) : 0;
    int bottomZero = (k>=3) ? getSumOfZeroNeighbours(field, lastNeigh, n, k, row+1, column) : 0;
    int leftZero = (k>=3) ? getSumOfZeroNeighbours(field, lastNeigh, n, k, row, column-1) : 0;
    int rightZero = (k>=3) ? getSumOfZeroNeighbours(field, lastNeigh, n, k, row, column+1) : 0;
    int topNeighZero = (k>=4) ? getSumOfNeighZeroNeighbours(field, lastNeigh, n, k, row-1, column) : 0;
    int bottomNeighZero = (k>=4) ? getSumOfNeighZeroNeighbours(field, lastNeigh, n, k, row+1, column) : 0;
    int leftNeighZero = (k>=4) ? getSumOfNeighZeroNeighbours(field, lastNeigh, n, k, row, column-1) : 0;
    int rightNeighZero = (k>=4) ? getSumOfNeighZeroNeighbours(field, lastNeigh, n, k, row, column+1) : 0;
    for (int i = max(row-k, 0); i <= (row+k) && i < n; i++) {
        int rowIdx = i % (2*k+1);
        for (int j = max(column-k, 0); j <= (column+k) && j < n; j++) {
            int diagonal = abs(i-row)+abs(j-column)+1;
            if (diagonal >= 2 && diagonal <= k && lastNeigh[rowIdx][j] == 0) {
                 if (diagonal == 2) {
                     if (!field[i][j]) {
                     	field[i][j] = true;
                     	diagonalSum[diagonal] += 1;
                     } else {
                        additionalPathToAlreadyAnalyzed += 1;
                     }
                 } else if (diagonal > 2) {
                     if (!field[i][j]) {
                        diagonalSum[diagonal] += 1;
                     }
                 }
            }
        }
    }
    //cout << " " << top << ":" << bottom << ":" << left << ":" << right << endl;
    /*for(int i = 2; i <= k; i++) {
        if (i == 2) {
            additionalSol = additionalSol*(sumDiagonals(diagonalSum, 3));
        } else if (i == 3) {
            additionalSol = additionalSol*(sumDiagonals(diagonalSum, 3) + fieldsWithNeighbours-1);
        } else if (i == 4) {
            additionalSol = additionalSol*(sumDiagonals(diagonalSum, 4) + fieldsWithNeighbours-1);
        }
    }*/
    diagonalSum[1] = top;
    diagonalSum[3] = topZero;
    diagonalSum[4] = topNeighZero;
    int topSum = getSum(diagonalSum, k, fieldsWithNeighbours);
    diagonalSum[1] = bottom;
    diagonalSum[3] = bottomZero;
    diagonalSum[4] = bottomNeighZero;
    int bottomSum = getSum(diagonalSum, k, fieldsWithNeighbours);
    diagonalSum[1] = left;
    diagonalSum[3] = leftZero;
    diagonalSum[4] = leftNeighZero;
    int leftSum = getSum(diagonalSum, k, fieldsWithNeighbours);
    diagonalSum[1] = right;
    diagonalSum[3] = rightZero;
    diagonalSum[4] = rightNeighZero;
    int rightSum = getSum(diagonalSum, k, fieldsWithNeighbours);
    //cout << " " << topSum << ":" << bottomSum << ":" << leftSum << ":" << rightSum << endl;
    //additionalSol = additionalSol + additionalPathToAlreadyAnalyzed;
    additionalSol =  topSum + bottomSum + leftSum + rightSum;// + additionalPathToAlreadyAnalyzed;
    //cout << " -> " << additionalSol << " --> " << additionalPathToAlreadyAnalyzed  << endl;
    return additionalSol%MODULO;
}

long long checkRowAdditionalSolutions(vector< vector<bool> > &field, vector< vector<int> > &lastNeigh, const int n, const int k, const int fieldsWithNeighbours, const int row) {
    long long additionalSol = 0;
    for (int i = 0; i < n; i++) {
       additionalSol += checkCellAdditionalSolutions(field, lastNeigh, n, k, fieldsWithNeighbours, row, i);
    }
    //cout << "ROW: " << row  << " " << additionalSol << endl;
    return additionalSol%MODULO;
}

long long  checkAdditionalSolutions(vector< vector<bool> > &field, const int n, const int k, const int fieldsWithNeighbours) {
    long long additionalSol = 0;
    vector< vector<int> > lastNeigh;
    lastNeigh.reserve(2*k+1);
    for (int i = 0; i < 2*k+1; i++) {
        vector<int> row;
        row.reserve(n);
        for (int j = 0; j < n; j++) {
            row.push_back(0);
        }
        lastNeigh.push_back(row);
    }
    char x;
    for (int i = 0; i < n; i++) {
        int lastRowIdx = 0;
        if(i>0) {
            lastRowIdx = (i-1) % (2*k+1);
        }
        int rowIdx = i % (2*k+1);
        for (int j = 0; j < n; j++) {
            int neigh = 0;
            if (field[i][j]) {
                neigh = SET;
                if (i>0 && lastNeigh[lastRowIdx][j] != SET) {
                    lastNeigh[lastRowIdx][j] += 1;
                }
                if (j>0 && lastNeigh[lastRowIdx][j] != SET) {
                    lastNeigh[rowIdx][j-1] += 1;
                }
            }
            if (neigh != SET && i>0 && field[i-1][j]) {
                neigh += 1;
            }
            if (neigh != SET && j>0 && field[i][j-1]) {
                neigh += 1;
            }
            lastNeigh[rowIdx][j] = neigh;
        }
        if (i > k) {
            additionalSol += checkRowAdditionalSolutions(field, lastNeigh, n, k, fieldsWithNeighbours, i-k-1);
        }
    }
    for (int i = max(n-k-1, 0); i < n; i++) {
        additionalSol += checkRowAdditionalSolutions(field, lastNeigh, n, k, fieldsWithNeighbours, i);
    }
    return additionalSol%MODULO;
}

int main( ) {
    int n,k;
    scanf("%d %d", &n, &k);
    //cout << n << ":" << k << endl;
    int size = 3000;
    vector< vector<bool> > field;
    field.reserve(size);
    for (int i = 0; i < size; i++) {
        vector<bool> row;
        row.reserve(size);
        field.push_back(row);
    }
    int fieldsWithNeighbours = readField(field, n);
    long long additionalSolutions = checkAdditionalSolutions(field, n, k, fieldsWithNeighbours);
    //cout << "Fields with neighbours: " << fieldsWithNeighbours << endl;
    //clock_t begin = clock();
    //printTime();
    long long result = (additionalSolutions + combinations(fieldsWithNeighbours, k))%MODULO;
    cout << result << endl;
    //printTime();
    //clock_t end = clock();
    //double elapsed_secs = double(end - begin) / CLOCKS_PER_SEC;
    //cout << "Time: " << elapsed_secs << endl;
    return 0;
}