#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;
}
vector<vector<int>> revg;
vector<vector<int>> revanc, revf;
vector<vector<ll>> revt;
vector<int> RA, RB;
void revdfs(int u, int p = 0) {
revanc[0][u] = p;
for (auto v : revg[u]) {
revdfs(v, u);
}
}
ll revjoin(ll t1, ll t2, int x, int y) {
if (RB[y] <= RA[x]) {
return t1 + RA[x] - RB[y] + t2;
} else {
return t1 + T - RB[y] + RA[x] + t2;
}
}
int revget(int x, int k) {
for (int h = 19; h >= 0; h -= 1) {
if (k & (1 << h)) {
x = revanc[h][x];
}
}
return x;
}
ll revlift(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 = revt[h][a];
} else {
ans = revjoin(ans, revt[h][a], b, a);
}
b = revf[h][a];
a = revanc[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]);
}
}
// invers
auto reva = a;
for (int i = 1; i <= n; i += 1) {
sort(all(reva[i]), [&](pair<int, int> a, pair<int, int> b) {
return a.second <= b.second;
});
}
vector<vector<pair<int, int>>> pref(n + 1);
for (int i = 1; i <= n; i += 1) {
pref[i].resize(m[i]);
pref[i][0] = {reva[i][0].first, 0};
for (int j = 1; j < m[i]; j += 1) {
pref[i][j] = max(pref[i][j - 1], {reva[i][j].first, j});
}
}
revg.resize(sum[n] + 1);
for (int i = 2; i <= n - 1; i += 1) {
for (int j = 0; j < m[i]; j += 1) {
int A = reva[i][j].first;
int B = reva[i][j].second;
int l = 0, r = m[i - 1] - 1, sol = -1;
while (l <= r) {
int mid = (l + r) / 2;
if (reva[i - 1][mid].second <= A) {
sol = mid;
l = mid + 1;
} else {
r = mid - 1;
}
}
if (sol == -1) {
revg[get_id(i - 1, pref[i - 1][m[i - 1] - 1].second)].push_back(get_id(i, j));
} else {
revg[get_id(i - 1, pref[i - 1][sol].second)].push_back(get_id(i, j));
}
}
}
revanc.assign(20, vector<int>(sum[n] + 1));
revf.assign(20, vector<int>(sum[n] + 1));
revt.assign(20, vector<ll>(sum[n] + 1));
RA.resize(sum[n] + 1);
RB.resize(sum[n] + 1);
for (int i = 1; i <= m[1]; i += 1) {
revdfs(i);
}
for (int i = 1; i <= n; i += 1) {
for (int j = 0; j < m[i]; j += 1) {
revt[0][get_id(i, j)] = reva[i][j].second - reva[i][j].first;
RA[get_id(i, j)] = reva[i][j].first;
RB[get_id(i, j)] = reva[i][j].second;
}
}
for (int h = 1; h < 20; h += 1) {
for (int i = 1; i <= sum[n]; i += 1) {
revanc[h][i] = revanc[h - 1][revanc[h - 1][i]];
}
}
for (int h = 0; h < 20; h += 1) {
for (int i = 1; i <= sum[n]; i += 1) {
revf[h][i] = revget(i, (1 << h) - 1);
}
}
for (int h = 1; h < 20; h += 1) {
for (int i = 1; i <= sum[n]; i += 1) {
int x = revf[h - 1][i];
revt[h][i] = revjoin(revt[h - 1][i], revt[h - 1][revanc[h - 1][i]], x, revanc[0][x]);
}
}
vector<int> heavy;
vector<int> id(n + 1);
for (int i = 1; i <= n; i += 1) {
if (m[i] >= K) {
heavy.push_back(i);
id[i] = heavy.size() - 1;
}
}
vector<vector<ll>> ans(heavy.size(), vector<ll>(heavy.size(), 1e18));
for (int i = 0; i < heavy.size(); i += 1) {
for (int j = i; j < heavy.size(); j += 1) {
int x = heavy[i];
int y = heavy[j] + 1;
for (int k = sum[x - 1] + 1; k <= sum[x]; k += 1) {
ll cur = lift(k, y - x);
ans[i][j] = min(ans[i][j], cur);
}
}
}
cin >> q;
for (int iq = 1; iq <= q; iq += 1) {
int l, r;
cin >> l >> r;
if (m[l] >= K && m[r - 1] >= K) {
cout << ans[id[l]][id[r - 1]] << "\n";
continue;
}
ll ans = 1e18;
if (m[l] <= K) {
for (int i = sum[l - 1] + 1; i <= sum[l]; i += 1) {
ans = min(ans, lift(i, r - l));
}
} else {
for (int i = sum[r - 2] + 1; i <= sum[r - 1]; i += 1) {
ans = min(ans, revlift(i, r - l));
}
}
cout << ans << "\n";
}
return 0;
}
