diff --git a/customWidgets.cpp b/customWidgets.cpp
index 00b4ca0..7654431 100644
--- a/customWidgets.cpp
+++ b/customWidgets.cpp
@@ -456,7 +456,7 @@ bigIconButton::bigIconButton(const QString &iconPath, const QString &description
     bgWidget = new QWidget(this);
     bgWidget->resize(this->size());
     radiusStyle = QString::asprintf("border-radius:%dpx;", cornerRadius);
-    bgWidget->setStyleSheet(radiusStyle + "background-color:#00000000");
+    bgWidget->setStyleSheet(radiusStyle + "background-color:#04000000");
     bgWidget->lower();
     bgWidget->show();
 
@@ -479,8 +479,8 @@ void bigIconButton::resizeEvent(QResizeEvent *event){
         indicator->move(this->width() * 0.45, this->height() - 21);
     }
     else{
-        indicator->resize(this->width() * 0.4, 6);
-        indicator->move(this->width() * 0.3, this->height() - 21);
+        indicator->resize(this->width() * 0.1, 6);
+        indicator->move(this->width() * 0.45, this->height() - 21);
     }
 }
 
@@ -497,7 +497,7 @@ void bigIconButton::enterEvent(QEnterEvent *event){
 }
 
 void bigIconButton::leaveEvent(QEvent *event){
-    bgWidget->setStyleSheet(radiusStyle + "background-color:#00000000");
+    bgWidget->setStyleSheet(radiusStyle + "background-color:#04000000");
     QPropertyAnimation *shorter = new QPropertyAnimation(indicator, "geometry", this);
     shorter->setStartValue(indicator->geometry());
     if(!onSelected)
diff --git a/graph_implement.cpp b/graph_implement.cpp
index 6093b4d..76e1ff8 100644
--- a/graph_implement.cpp
+++ b/graph_implement.cpp
@@ -482,7 +482,7 @@ void AMLGraph::DelVex(int vexID){
             AMLArc *nextArc = preArc->nextOutArc;
             while(nextArc != nullptr){
                 if(nextArc->inVexID == vexID || nextArc->outVexID == vexID){
-                    if(preArc->outVexID == i){
+                    if(preArc->outVexID == i || preArc->outVexID == -i){
                         if(nextArc->outVexID == i){
                             preArc->nextOutArc = nextArc->nextOutArc;
                             nextArc->nextOutArc = nullptr;
@@ -506,20 +506,52 @@ void AMLGraph::DelVex(int vexID){
                             delete nextArc;
                         }
                     }
-                    nextArc = preArc->outVexID == i ? preArc->nextOutArc : preArc->nextInArc;
+                    nextArc = (preArc->outVexID == i || preArc->outVexID == -i) ? preArc->nextOutArc : preArc->nextInArc;
                     continue;
                 }
-                preArc = nextArc;
-                nextArc = preArc->outVexID == i ? preArc->nextOutArc : preArc->nextInArc;
                 if(preArc->inVexID > vexID)
                     preArc->inVexID = - preArc->inVexID;
                 else if(preArc->inVexID < 0)
-                    preArc->inVexID = - preArc->inVexID;
+                    preArc->inVexID = - preArc->inVexID - 1;
                 if(preArc->outVexID > vexID)
                     preArc->outVexID = - preArc->outVexID;
                 else if(preArc->outVexID < 0)
-                    preArc->outVexID = - preArc->outVexID;
+                    preArc->outVexID = - preArc->outVexID - 1;
+                preArc = nextArc;
+                nextArc = (preArc->outVexID == i || preArc->outVexID == -i) ? preArc->nextOutArc : preArc->nextInArc;
+
+                /********************************************************************************************/
+                //Issue #1
+                /*How this causes issue:
+                 *   Example： when vexID is 1
+                 *   preArc = nextArc => preArc: -3 -> -2
+                 *   nextArc = ... => nextArc : 3 -> 1
+                 *   Adjust pre Arc to => preArc: 2 -> 1
+                 *   In next loop: nextArc->inVexID == 1 => judge if preArc->nextOutArc == 3 (in fact it is)
+                 *   preArc->nextOutArc != 3 -> wrongly connect next out arc of 3 -> 1 to next out arc of 2 -> 1
+                 *   which leads to wrong operations
+                 */
+
+                //if(preArc->inVexID > vexID)
+                //    preArc->inVexID = - preArc->inVexID;
+                //else if(preArc->inVexID < 0)
+                //    preArc->inVexID = - preArc->inVexID - 1;
+                //if(preArc->outVexID > vexID)
+                //    preArc->outVexID = - preArc->outVexID;
+                //else if(preArc->outVexID < 0)
+                //    preArc->outVexID = - preArc->outVexID - 1;
+
+                /********************************************************************************************/
+
             }
+            if(preArc->inVexID > vexID)
+                preArc->inVexID = - preArc->inVexID;
+            else if(preArc->inVexID < 0)
+                preArc->inVexID = - preArc->inVexID - 1;
+            if(preArc->outVexID > vexID)
+                preArc->outVexID = - preArc->outVexID;
+            else if(preArc->outVexID < 0)
+                preArc->outVexID = - preArc->outVexID - 1;
             outVexList[i].firstArc = dummyHead->nextOutArc;
             delete dummyHead;
         }
diff --git a/mainwindow.cpp b/mainwindow.cpp
index 5e77620..ead9be3 100644
--- a/mainwindow.cpp
+++ b/mainwindow.cpp
@@ -49,17 +49,21 @@ void MainWindow::Init(){
     border->show();
     /*****************************************************************/
 
-    /* Create settings page */
+    /* Create about page */
     defaultSettingsPage = new SlidePage(cornerRadius, "ABOUT", ui->mainWidget);
     textInputItem *version = new textInputItem("version", defaultSettingsPage);
-    version->setValue("1.0");
+    version->setValue("1.1 beta");
     version->setEnabled(false);
     textInputItem *updateDate = new textInputItem("last-upd", defaultSettingsPage);
-    updateDate->setValue("2021/12/4");
+    updateDate->setValue("2021/12/5");
     updateDate->setEnabled(false);
     textInputItem *Author = new textInputItem("author", defaultSettingsPage);
     Author->setValue("Linloir | Made with love");
     Author->setEnabled(false);
+    textInputItem *GitHub = new textInputItem("git", defaultSettingsPage);
+    GitHub->setValue("github.com/Linloir");
+    GitHub->setEnabled(false);
+    defaultSettingsPage->AddContent(GitHub);
     defaultSettingsPage->AddContent(Author);
     defaultSettingsPage->AddContent(updateDate);
     defaultSettingsPage->AddContent(version);
diff --git a/mainwindow.h b/mainwindow.h
index f6b9daf..da435bc 100644
--- a/mainwindow.h
+++ b/mainwindow.h
@@ -48,7 +48,7 @@ private:
     QPoint lastPos;
     void mouseMoveEvent(QMouseEvent *event);
     void mousePressEvent(QMouseEvent *event);
-    void mouseReleaseEvent(QMouseEvent *event){mousePressed = false;}
+    void mouseReleaseEvent(QMouseEvent *event){mousePressed = false;if(event->globalPosition().y() < 2)  controlWindowScale();}
     void resizeEvent(QResizeEvent *event);
 
     bool maximized = false;