#include<bits/stdc++.h>
using namespace std;

const int md = 1e9 + 7;

struct matrix{
    int a[105][105], n;
    matrix(){
        n = 0;
        for (int i = 0; i < 105; ++i){
            for (int j = 0; j < 105; ++j){
                a[i][j] = 0;
            }
        }
    }
    void print(){
        cout <<"SIZE "<<n<<endl;
        for (int i = 1; i <= n; ++i){
            for (int j = 1; j <= n; ++j){
                cout <<a[i][j]<<" ";
            }
            cout <<endl;
        }
    }
};

matrix operator * (matrix a, matrix b){
    matrix c = matrix();
    c.n = a.n;
    for (int i = 1; i <= a.n; ++i){
        for (int j = 1; j <= a.n; ++j){
            for (int k = 1; k <= a.n; ++k){
                c.a[i][j] = (c.a[i][j] + 1ll * a.a[i][k] * b.a[k][j]) % md;
            }
        }
    }
    return c;
}

int n, m, num[105][105];
string a[105], b[105][105];
vector < pair < int, int > > g;

matrix bin_pow(matrix a, int b){
    matrix s = matrix();
    s.n = a.n;
    for (int i = 1; i <= s.n; ++i)s.a[i][i] = 1;
    while (b > 0){
        if (b % 2 == 0){
            a = a * a;
            b >>= 1;
        }else {
            s = s * a;
            b--;
        }
    }
    return s;
}

int main(){
    ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0);
    cin >>n>>m;
    for (int i = 1; i <= m; ++i){
        int k;
        cin >>k;
        cin >>a[i];
        for (int j = 1; j <= k; ++j){
            b[i][j] = a[i].substr(0, j);
        }
    }
    a[0] = " ";
    int k = 1;
    g.push_back(make_pair(0, 0));
    num[0][0] = 1;
    matrix aaa = matrix();
    for (int i = 0; i < k; ++i){
        string cur = a[g[i].first].substr(0, g[i].second);
        for (char q = 'a'; q <= 'z'; ++q){
            string s = cur + q;
            bool o = 1;
            for (int j = 1; j <= m; ++j){
                if (s == a[j]){
                    o = 0;
                    break;
                }
            }
            if (!o)continue;
            int len = -1, pos = -1;
            int mx = s.size();
            for (int l = mx; l >= 1; --l){
                for (int j = 1; j <= m; ++j){
                    if (a[j].size() >= s.size() && b[j][l] == s){
                        len = l;
                        pos = j;
                        break;
                    }
                }
                if (len != -1)break;
                s.erase(0, 1);
            }
            if (len == -1){
                len = 0;
                pos = 0;
            }
            if (num[pos][len] == 0){
                num[pos][len] = ++k;
                g.push_back(make_pair(pos, len));
            }
            aaa.a[i + 1][num[pos][len]]++;
        }
    }
    aaa.n = k;
    /*for (int i = 0; i < g.size(); ++i){
        cout <<g[i].first<<" "<<g[i].second<<endl;
    }*/
    //aaa.print();
    aaa = bin_pow(aaa, n);
    int ans = 0;
    for (int i = 1; i <= aaa.n; ++i){
        ans = (ans + aaa.a[1][i]) % md;
    }
    cout <<ans;
}