int lpin=11;
int BB1=10;
int BB2=9;
int dt=100;
int Sb1;
int Sb2;
int bright=0;

void setup() {
  // put your setup code here, to run once:
pinMode(lpin, OUTPUT);
pinMode(BB1, INPUT);
pinMode(BB2, INPUT);
Serial.begin(115200);
}

void loop() {
  // put your main code here, to run repeatedly:
Sb1=digitalRead(BB1);
Sb2=digitalRead(BB2);
Serial.print("Button 1 = ");
Serial.print(Sb1);
Serial.print(" Button 2 = ");
Serial.print (Sb2);
delay(dt);
if (Sb1==0){
  bright = bright+5;
}
if (Sb2==0){
  bright=bright-5;
}
if ( bright>255){
  bright=255;
}
if (bright<0){
  bright=0;
}
Serial.print(" Led Brightness = ");
Serial.println(bright);

analogWrite(lpin,bright);
}