html,body {
  margin: 0;
  padding: 0;
  height: 100%;
  width: 100%;
  font-family: Arial, sans-serif;
}

.container_div {
  display: flex;
  flex-direction: column;
  height: 100%;
  width: 100%;
}

.top_div {
  height: 40px;
  font-size: 18px;
  display: flex;
  align-items: center;
  justify-content: center;
}

.bottom_div {
  display: flex;
  flex: 1 0 0;
  overflow: hidden;
}

.left_div {
  flex: 1 0 0;
  overflow: hidden;
  display: flex;
  border-right: 1px solid #ccc;
  flex-direction: column;
  box-sizing: border-box;
}

.center_div {
  flex: 1 0 0;
  overflow: hidden;
  display: flex;
  padding: 10px;
}

.right_div {
  flex: 1 0 0;
  overflow: hidden;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-direction: column;
}