#include<bits/stdc++.h>
#define fi first
#define se second
#define pitem item*
using namespace std;
typedef long long ll;
typedef unsigned long long ull;
typedef vector<int> vi;
typedef vector<ll> vl;
const int N=1e5+10;
const int INFi=2e9;
const ll INFl=1e16;
const ll mod2=998244353;
const ll mod=1e9+7;
const ll mod3=2027865967;
const ll p=70032301;
const ull p2=913;
const int L=17;
int n,m;
vector<pair<int,int>> t[N];
vi t2[N],naj[N][L];
pair<int,ll> jp[N][L];
pair<int,int> num[N];
map<pair<int,int>, ll> mm;
ll zn(int a,int b,int ost){
ll curr=0;
b--;
for(int i=ost;i>=0;i--){
if(num[jp[a][i].fi].fi<=b){
curr+=jp[a][i].se;
a=jp[a][i].fi;
}
}
curr+=t[b][num[a].se].se-t[b][num[a].se].fi;
return curr;
}
void solve(){
cin>>n>>m;
vector<pair<int,int>> cr;
int li=0;
for(int i=1;i<n;i++){
int a;
cin>>a;
while(a--){
int x,d;
cin>>x>>d;
cr.push_back({x,d});
}
sort(cr.begin(),cr.end());
reverse(cr.begin(),cr.end());
while(cr.size()){
while(t[i].size() and t[i].back().se>=cr.back().se) t[i].pop_back();
t[i].push_back(cr.back());
cr.pop_back();
}
for(int i2=0;i2<t[i].size();i2++){
t2[i].push_back(++li);
num[li]={i,i2};
}
}
num[li+1].fi=n;
for(int i=0;i<L;i++) jp[li+1][i].fi=li+1;
for(int i=1;i<n;i++){
int curr=0;
for(int i2=0;i2<t[i].size();i2++){
while(curr<t[i+1].size() and t[i+1][curr].fi<t[i][i2].se) curr++;
ll xd=t[i][i2].se-t[i][i2].fi;
if(curr==t[i+1].size()){
if(i<n-1) xd+=m-t[i][i2].se+t[i+1][0].fi,jp[t2[i][i2]][0].fi=t2[i+1][0];
else jp[t2[i][i2]][0].fi=li+1;
}else{
xd+=t[i+1][curr].fi-t[i][i2].se;
jp[t2[i][i2]][0].fi=t2[i+1][curr];
}
jp[t2[i][i2]][0].se=xd;
}
}
for(int i2=1;i2<L;i2++){
for(int i=1;i<=li;i++){
int g=jp[i][i2].fi;
jp[i][i2].se=jp[i][i2-1].se+jp[jp[i][i2-1].fi][i2-1].se;
jp[i][i2].fi=jp[jp[i][i2-1].fi][i2-1].fi;
}
}
vector<pair<int,pair<ll,int>>> pom;
int q;
cin>>q;
for(int i=1;i<=q;i++){
int a,b;
cin>>a>>b;
if(mm.count(make_pair(a,b))>0){
cout<<mm[make_pair(a,b)]<<"\n";
continue;
}
ll res=INFl;
int xd=b-a-1;
if(xd==0){
for(int i2=0;i2<t2[a].size();i2++){
res=min(res,(ll)t[b-1][i2].se-(ll)t[b-1][i2].fi);
}
mm[make_pair(a,b)]=res;
cout<<res<<"\n";
}else{
int ost=0;
for(int i2=0;i2<L;i2++){
if((1<<i2)<=xd) ost=i2;
}
if(!naj[a][ost].size()){
pom.clear();
for(auto u:t2[a]) pom.push_back({jp[u][ost].fi,{jp[u][ost].se,u}});
sort(pom.begin(),pom.end());
for(int i3=0;i3<pom.size();i3++){
if(i3==0 or pom[i3-1].fi!=pom[i3].fi)
naj[a][ost].push_back(pom[i3].se.se);
}
}
for(auto u:naj[a][ost]) res=min(res,zn(u,b,ost));
mm[make_pair(a,b)]=res;
cout<<res<<"\n";
}
}
}
int main(){
ios_base::sync_with_stdio(0),cin.tie(0);
int tt=1;
while(tt--) solve();
}
