#include <bits/stdc++.h>
#include <cassert>

using namespace std;
using ll = long long;

#define all(x) (x).begin(), (x).end()
#define sz(x) (int)(x).size()
#define pb push_back
#define ff first
#define sc second

mt19937 rnd(chrono::steady_clock::now().time_since_epoch().count());
template<typename T>
void shuf(vector<T>& a) {
    for (int i = 1; i < sz(a); i++) swap(a[i], a[rnd() % (i + 1)]);
}

int dp[2001][2001][2];
const int mod = 1e9 + 7;
int sum(int x, int y) {return (x + y >= mod ? x + y - mod : x + y);}
int mul(int x, int y) {return (x * 1ll * y) % mod;}
int diff(int x, int y) {return (x - y < 0 ? x - y + mod : x - y);}
int rev2 = (mod + 1) / 2;

void solve() {
    int n; cin >> n;
    vector<string> s(n);
    for (int i = 0; i < n; i++) cin >> s[i];
    int ans = 1;
    for (int i = 0; i < n; i++) {
        for (int j = 0; j < n; j++) {
            if (s[i][j] == '.') ans = mul(ans, 2);
        }
    }
    dp[0][1][0] = dp[1][0][1] = ans;
    for (int sm = 2; sm <= 2 * n; sm++) {
        for (int i = 0; i <= n; i++) {
            if (sm - i < 0 || sm - i > n) continue;
            int j = sm - i;
            if (i > 0) {
                dp[i][j][1] = sum(dp[i][j][1], dp[i - 1][j][1]);
                if (j > 0 && s[i - 1][j - 1] != 'W') dp[i][j][1] = sum(dp[i][j][1], mul(dp[i - 1][j][0], rev2));
            }
            if (j > 0) {
                dp[i][j][0] = sum(dp[i][j][0], dp[i][j - 1][0]);
                if (i > 0 && s[i - 1][j - 1] != 'W') dp[i][j][0] = sum(dp[i][j][0], mul(dp[i][j - 1][1], rev2));
            }
        }
    }
    cout << sum(dp[n][n][0], dp[n][n][1]) << '\n';
}

signed main() {
    int tt = 1;
    #ifdef LOCAL
        freopen("in.txt", "r", stdin);
        freopen("out.txt", "w", stdout);
        cin >> tt;
    #else
        ios::sync_with_stdio(false);
        cin.tie(0); cout.tie(0);
    #endif

    while (tt--) {
        solve();
    }

    return 0;
}