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

body {
     margin: 0;
     font-family: sans-serif;
     display: flex;
     flex-direction: column;
     height: 100vh;
}

.maintab {
     display: flex;
     flex: 1;
     justify-content: space-around;
}

header {
     position: fixed;
     top: 0;
     left: 0;
     right: 0;
     height: 10vh;
     background: white;
     z-index: 9999;
     display: flex;
     align-items: center;
     padding: 0 20px;
     border-bottom: 1px solid #ddd;
}

nav {
     width: 380px;
     border: 2px solid blue;
     padding: 20px;

     position: fixed;
     left: 0;
     top: 10vh;
     height: 90vh;
}

aside {
     width: 380px;
     border: 2px solid purple;
     padding: 20px;

     position: fixed;
     right: 0;
     top: 10vh;
     height: 90vh;

     overflow: hidden;
}

aside:hover {
     overflow-y: auto;
}

main {
     margin-left: 380px;
     margin-right: 380px;
     padding: 20px;
     border: 2px solid green;

     min-height: 100vh;
     height: 110vh;
     width: 70%;
     position: relative;
     top: 10vh;
}

.friends {
     padding: 10px;
     margin-bottom: 22px;
     margin-top: 45px;
     height: 270px;
     box-shadow: 0 4px 6px rgba(0, 0, 0, 0.12);
     display: flex;
     flex-direction: column;
     border-radius: 15px;
}

.trending {
     padding: 10px;
     margin-bottom: 22px;
     height: 270px;
     box-shadow: 0 4px 6px rgba(0, 0, 0, 0.12);
     border-radius: 15px;
}

.ads {
     padding: 10px;
     height: 270px;
     box-shadow: 0 4px 6px rgba(0, 0, 0, 0.12);
     border-radius: 15px;
}

div.box1 {
     width: 100%;
     height: 50px;
     margin-top: 17px;
     display: flex;
}

div.box1:hover {
     background-color: silver;
     border-radius: 27px 9px 9px 27px;
     transition: background-color 0.2s;
}

div.box2 {
     width: 100%;
     height: 50px;
     margin-top: 17px;
     display: flex;
}

div.box2:hover {
     background-color: silver;
     border-radius: 27px 9px 9px 27px;
     transition: background-color 0.2s;
}

div.box3 {
     width: 100%;
     height: 50px;
     margin-top: 17px;
     display: flex;
}

div.box3:hover {
     background-color: silver;
     border-radius: 27px 9px 9px 27px;
     transition: background-color 0.2s;
}

img.image1 {
     width: 50px;
     height: 50px;
     border-radius: 50%;
     border: 0.5px solid rgb(227, 227, 227);
}

img.image2 {
     width: 50px;
     height: 50px;
     border-radius: 50%;
     border: 0.5px solid rgb(227, 227, 227);
}

img.image3 {
     width: 50px;
     height: 50px;
     border-radius: 50%;
     border: 0.5px solid rgb(227, 227, 227);
}

p.p1 {
     margin-top: 13px;
     margin-left: 5%;
     font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
     cursor: pointer;
}

p.p2 {
     margin-top: 13px;
     margin-left: 5%;
     font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
     cursor: pointer;
}

p.p3 {
     margin-top: 13px;
     margin-left: 5%;
     font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
     cursor: pointer;
}

div.icon1 {
     width: 50px;
     height: 41px;
     background-color: rgb(227, 227, 227);
     margin-left: 5%;
     margin-top: 4px;
     border-radius: 25px;
     position: relative;
     left: 30%;
}

div.icon2 {
     width: 50px;
     height: 41px;
     background-color: rgb(227, 227, 227);
     margin-left: 5%;
     margin-top: 4px;
     border-radius: 25px;
     position: relative;
     left: 30%;
}

div.icon3 {
     width: 50px;
     height: 41px;
     background-color: rgb(227, 227, 227);
     margin-left: 5%;
     margin-top: 4px;
     border-radius: 25px;
     position: relative;
     left: 30%;
}

img.email1 {
     width: 25px;
     height: 25px;
     position: relative;
     left: 12px;
     top: 8px;
}

img.email2 {
     width: 25px;
     height: 25px;
     position: relative;
     left: 12px;
     top: 8px;
}

img.email3 {
     width: 25px;
     height: 25px;
     position: relative;
     left: 12px;
     top: 8px;
}



@media (max-width: 650px) {
     div.icon1, div.icon2, div.icon3 {
          display: none;
     }
     p.p1, p.p2, p.p3 {
          font-size: 12px;
          position: relative;
          left: 5px;
          bottom: 2px;
     }
     img.image1, img.image2, img.image3 {
          width: 40px;
          height: 40px;
     }

}

@media (max-width: 850px) {
nav {
          display: none;
     }

     main {
     width: 500px;
     margin-left: 0px;
     }

}

@media (max-width: 800px) {
aside {
display: none;
}
}

@media (max-width: 800px) {
     nav, aside {
          display: none;
     }

     main {
          margin: 0;
          width: 100%;
          padding: 15px;
          border: none;
          border: 1px solid green;
     }
}

h3 {
     margin-top: 22px;
     margin-bottom: 9px;
     font-weight: normal;
     cursor: pointer;
}

h3:hover {
     text-decoration: underline;
}

p.Jointag {
     margin-bottom: 20px;
     font-size: 22px;
     font-weight: normal;
     font-weight: bolder;
     font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
     cursor: pointer;
}

h4.h41 {
     margin-bottom: 20px;
     width: 75%;
     line-height: 25px;
     cursor: pointer;
     font-size: 20px;
     font-weight: normal;
}

button.button {
     cursor: pointer;
     width: 120px;
     height: 38px;
     border-radius: 8px;
     background-color: rgb(206, 201, 201);
     border: none;
     font-size: 18px;
     font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
     font-weight: normal;
}

button.button:hover {
     background-color: white;
}