#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
const ll inf = 2e18;
const ll B = 100;
ll ri[100010][20], rt[100010][20];
ll li[100010], lt[100010];
ll pre1[100010], pre2[1010][100010];
int main() {
ios_base :: sync_with_stdio(false); cin.tie(NULL);
ll N, T;
cin >> N >> T;
vector<vector<pair<ll,ll>>> a(N-1);
vector<ll> st(N);
ll tot = 0;
for (ll i=0; i<N-1; i++) {
ll M;
cin >> M;
a[i].resize(M);
for (ll j=0; j<M; j++) {
cin >> a[i][j].first >> a[i][j].second;
}
sort(a[i].begin(), a[i].end(), [&] (pair<ll,ll> &u, pair<ll,ll> &v) {
return u.first != v.first ? u.first > v.first : u.second < v.second;
});
vector<pair<ll,ll>> t = {a[i][0]};
for (ll j=1; j<M; j++) {
if (a[i][j].second < t.back().second) {
t.push_back(a[i][j]);
}
}
a[i] = t;
reverse(a[i].begin(), a[i].end());
st[i] = tot;
tot += a[i].size();
}
st[N-1] = tot;
memset(ri, -1, sizeof(ri));
memset(li, -1, sizeof(li));
for (ll i=0; i<N-1; i++) {
for (ll j=0; j<a[i].size(); j++) {
if (i != N-2) {
ll nxt = lower_bound(a[i+1].begin(), a[i+1].end(), make_pair(a[i][j].second, 0LL)) - a[i+1].begin();
if (nxt == a[i+1].size()) {
nxt = 0;
}
ri[st[i]+j][0] = st[i+1] + nxt;
rt[st[i]+j][0] = (a[i+1][nxt].first - a[i][j].second + T) % T + (a[i+1][nxt].second - a[i+1][nxt].first);
}
if (i != 0) {
ll prv = upper_bound(a[i-1].begin(), a[i-1].end(), make_pair(inf, a[i][j].first),
[&](pair<ll,ll>u, pair<ll,ll>v) {
return u.second != v.second ? u.second < v.second : u.first < v.first;
}) - a[i-1].begin() - 1;
if (prv == -1) {
prv = a[i-1].size() - 1;
}
li[st[i]+j] = st[i-1] + prv;
lt[st[i]+j] = (a[i][j].first - a[i-1][prv].second + T) % T + (a[i-1][prv].second - a[i-1][prv].first);
}
}
}
for (ll lv=1; lv<=16; lv++) {
for (ll i=0; i<tot; i++) {
if (ri[i][lv-1] != -1 && ri[ri[i][lv-1]][lv-1] != -1) {
ri[i][lv] = ri[ri[i][lv-1]][lv-1];
rt[i][lv] = rt[i][lv-1] + rt[ri[i][lv-1]][lv-1];
}
}
}
vector<ll> big, sid(N-1);
for (ll i=0; i<N-1; i++) {
if (a[i].size() > B) {
sid[i] = big.size();
big.push_back(i);
}
}
//assert(big.size() < 350);
for (ll i=0; i<big.size(); i++) {
pre2[i][big[i]] = inf;
for (ll k=0; k<a[big[i]].size(); k++) {
pre1[st[big[i]]+k] = 0;
pre2[i][big[i]] = min(pre2[i][big[i]], a[big[i]][k].second - a[big[i]][k].first);
}
for (ll j=big[i]+1; j<N-1; j++) {
pre2[i][j] = inf;
for (ll k=0; k<a[j].size(); k++) {
pre1[st[j]+k] = pre1[li[st[j]+k]] + lt[st[j]+k];
pre2[i][j] = min(pre2[i][j], pre1[st[j]+k] + a[j][k].second - a[j][k].first);
}
}
}
ll Q;
cin >> Q;
while (Q --) {
ll L, R;
cin >> L >> R;
L --; R -= 2;
if (a[L].size() > B) {
cout << pre2[sid[L]][R] << '\n';
}
else {
ll ans = inf;
for (ll i=0; i<a[L].size(); i++) {
ll r = st[L] + i;
ll rp = L;
ll cur = a[L][i].second - a[L][i].first;
for (ll lv=16; lv>=0; lv--) {
if (rp + (1<<lv) <= R) {
rp += 1 << lv;
cur += rt[r][lv];
r = ri[r][lv];
}
}
ans = min(ans, cur);
}
cout << ans << '\n';
}
}
}
