.block{
  display: flex;
  top: 0;
}
.sideber{
  flex-basis: 20%;
  display: flex;
  top: 20vh;
}
.box{
  background-color: black;
  color: white;
}
.sidebar_name{
  padding: 5% 10%;
}
.sidenav_li{
  padding: 5% 10%;
  color: black;
  background-color: rgb(239, 254, 254);
  border: 2px solid black;
  border-top: 0px;

}
.box{
  position: fixed;
  top: 120px;
  left: 5%;
  width: 200px;
}


@media screen and (max-width:1024px) {
  .sidebar_name{
    padding: 8% 5%;
    padding-left: 10%;
  }
  .box{
    left: 3%;
    width: 125px;
  }
  .sidenav_li_a{
    font-size: 15px;
  }
  .sidenav_li{
    padding: 7% 10%;
    padding-left: 15%;
  }
  .sideber{
    flex-basis: 15%;
  }
}
@media screen and (max-width:767px) {
  .sideber{
    display: none;
  }
}

.menu_smartphone{
  display: none;
}
@media screen and (max-width:767px) {
  .menu_smartphone{
    display: flex;
    width: 80%;
    padding: 0 10% 5px;
    flex-direction: column;
  }
  .SmartphoneMenu_name{
    display: flex;
    padding-top: 3px;
    padding-bottom: 3px;
    padding-left: 20px;
    border: 1px solid black;
    font-size: 16px;
    background-color: black;
    color: white;
  }
  .SmartphoneMenu_nav{
    border: 1px solid black;
    padding-top: 3px;
    padding-bottom: 3px;
    display: flex;
    flex-direction: row;
    flex-wrap: wrap;
  }
  .SmartphoneMenu_li{
    font-size: 14px;
    width: 33.3%;
    padding: 2px 0;
  }
  .SmartphoneMenu_list{
    padding-top: 2px;
    padding-bottom: 2px;
    padding-left: 15px;

  }
}
@media screen and (max-width:400px){
  .SmartphoneMenu_li{
    font-size: 14px;
    width: 50%;
  }
  .SmartphoneMenu_list{
    padding-top: 2px;
    padding-bottom: 2px;
    padding-left: 10px;
  }
  .menu_smartphone{
    width: 100%;
    padding: 0 0 5px;
  }
}
@media screen and (max-width:250px){
  .SmartphoneMenu_list{
    padding-left: 5px;
  } 
  
}


html {
  scroll-behavior: smooth;
}  
.pagetop {
  height: 50px;
  width: 50px;
  position: fixed;
  right: 30px;
  bottom: 30px;
  background: #fff;
  border: solid 2px #000;
  border-radius: 50%;
  display: flex;
  justify-content: center;
  align-items: center;
  z-index: 2;
} 

.pagetop__arrow {
  height: 10px;
  width: 10px;
  border-top: 3px solid #000;
  border-right: 3px solid #000;
  transform: translateY(20%) rotate(-45deg);
}