#include <bits/stdc++.h>
using namespace std;
#define ll long long
#define ld long double
#define all(a) a.begin(), a.end()
#define rall(a) a.rbegin(), a.rend()
const int K = 316;
int n, T, q;
vector<vector<int>> g;
vector<vector<int>> anc, f;
vector<vector<ll>> t;
vector<int> dep;
vector<int> A, B;
void dfs(int u, int p = 0) {
anc[0][u] = p;
for (auto v : g[u]) {
dep[v] = dep[u] + 1;
dfs(v, u);
}
}
ll join(ll t1, ll t2, int x, int y) {
if (B[x] <= A[y]) {
return t1 + A[y] - B[x] + t2;
} else {
return t1 + T - B[x] + A[y] + t2;
}
}
int get(int x, int k) {
for (int h = 19; h >= 0; h -= 1) {
if (k & (1 << h)) {
x = anc[h][x];
}
}
return x;
}
ll lift(int a, int k) {
ll ans = 0;
int b = a;
for (int h = 19; h >= 0; h -= 1) {
if (k & (1 << h)) {
if (ans == 0) {
ans = t[h][a];
} else {
ans = join(ans, t[h][a], b, a);
}
b = f[h][a];
a = anc[h][a];
}
}
return ans;
}
int32_t main() {
if (1) {
ios::sync_with_stdio(0);
cin.tie(0);
cout.tie(0);
}
cin >> n >> T;
vector<int> m(n + 1);
vector<vector<pair<int, int>>> a(n + 1);
for (int i = 1; i <= n - 1; i += 1) {
cin >> m[i];
a[i].resize(m[i]);
for (int j = 0; j < m[i]; j += 1) {
cin >> a[i][j].first >> a[i][j].second;
}
sort(all(a[i]));
}
m[n] = 1;
a[n].push_back({T, T});
vector<int> sum(n + 1);
for (int i = 1; i <= n; i += 1) {
sum[i] = sum[i - 1] + m[i];
}
auto get_id = [&](int i, int j) {
return sum[i - 1] + j + 1;
};
vector<vector<pair<int, int>>> suff(n + 1);
for (int i = 1; i <= n; i += 1) {
suff[i].resize(m[i]);
suff[i][m[i] - 1] = {a[i][m[i] - 1].second, m[i] - 1};
for (int j = m[i] - 2; j >= 0; j -= 1) {
suff[i][j] = min(suff[i][j + 1], {a[i][j].second, j});
}
}
g.resize(sum[n] + 1);
for (int i = 1; i <= n - 1; i += 1) {
for (int j = 0; j < m[i]; j += 1) {
int A = a[i][j].first;
int B = a[i][j].second;
int l = 0, r = m[i + 1] - 1, sol = -1;
while (l <= r) {
int mid = (l + r) / 2;
if (a[i + 1][mid].first >= B) {
sol = mid;
r = mid - 1;
} else {
l = mid + 1;
}
}
if (sol == -1) {
g[get_id(i + 1, suff[i + 1][0].second)].push_back(get_id(i, j));
} else if (sol != -1) {
g[get_id(i + 1, suff[i + 1][sol].second)].push_back(get_id(i, j));
}
}
}
dep.resize(sum[n] + 1);
anc.assign(20, vector<int>(sum[n] + 1));
f.assign(20, vector<int>(sum[n] + 1));
t.assign(20, vector<ll>(sum[n] + 1));
dfs(sum[n]);
A.resize(sum[n] + 1);
B.resize(sum[n] + 1);
for (int i = 1; i <= n; i += 1) {
for (int j = 0; j < m[i]; j += 1) {
t[0][get_id(i, j)] = a[i][j].second - a[i][j].first;
A[get_id(i, j)] = a[i][j].first;
B[get_id(i, j)] = a[i][j].second;
}
}
for (int h = 1; h < 20; h += 1) {
for (int i = 1; i <= sum[n]; i += 1) {
anc[h][i] = anc[h - 1][anc[h - 1][i]];
}
}
for (int h = 0; h < 20; h += 1) {
for (int i = 1; i <= sum[n]; i += 1) {
f[h][i] = get(i, (1 << h) - 1);
}
}
for (int h = 1; h < 20; h += 1) {
for (int i = 1; i <= sum[n]; i += 1) {
int x = f[h - 1][i];
t[h][i] = join(t[h - 1][i], t[h - 1][anc[h - 1][i]], x, anc[0][x]);
}
}
vector<int> heavy;
for (int i = 1; i <= n; i += 1) {
if (m[i] >= K) {
heavy.push_back(i);
}
}
map<pair<int, int>, ll> ans;
for (int i = 0; i < heavy.size(); i += 1) {
for (int j = i + 1; j < heavy.size(); j += 1) {
int x = heavy[i];
int y = heavy[j];
for (int k = sum[x - 1] + 1; k <= sum[x]; k += 1) {
ll cur = lift(k, y - x);
if (ans.count({x, y}) == 0) {
ans[{x, y}] = cur;
} else {
ans[{x, y}] = min(ans[{x, y}], cur);
}
}
}
}
cin >> q;
for (int iq = 1; iq <= q; iq += 1) {
int l, r;
cin >> l >> r;
if (m[l] >= K && m[r] >= K) {
cout << ans[{l, r}] << "\n";
continue;
}
ll ans = 1e18;
for (int i = sum[l - 1] + 1; i <= sum[l]; i += 1) {
ans = min(ans, lift(i, r - l));
}
cout << ans << "\n";
}
return 0;
}
