* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

body, html {
  height: 100%;
  width: 100%;
  font-family: sans-serif;
}


#caly {
  display: flex;
  flex-direction: column;
  min-height: 100vh;
}


header {
  width: 100%;
  background-color: #50514F;
  text-align: center;
  font-size: clamp(1.5rem, 2.5vw, 2rem);
  color: white;
  padding: 15px 10px;
  display: flex;
  align-items: center;
  justify-content: center;
}


#srodek {
  flex: 1;
  display: flex;
  width: 100%;
}


#boczny {
  width: 15%;
  min-width: 160px;
  background-color: #CBD4C2;
  text-align: center;
  font-size: 20px;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: flex-start;
  padding: 20px 10px;
}

main {
  flex: 1;
  background-color: #FFFCFF;
  padding: 20px;
  overflow-y: auto;
}

footer {
  background-color: #50514F;
  color: white;
  width: 100%;
  text-align: center;
  padding: 20px 10px;
  font-size: 18px;
}


@media (max-width: 768px) {
  header {
    font-size: clamp(1.2rem, 4vw, 1.6rem);
    padding: 12px 8px;
  }

  #srodek {
    flex-direction: column;
  }

  #boczny {
    width: 100%;
    font-size: clamp(1rem, 3.5vw, 1.3rem);
    padding: 12px 0;
    justify-content: center; 
  }

  main {
    flex: 1;
    width: 100%;
    padding: 4vw;
    font-size: clamp(1rem, 2.8vw, 1.2rem);
    overflow-y: auto;
  }

  footer {
    padding: 15px 10px;
    font-size: clamp(1rem, 3vw, 1.2rem);
  }
}