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

body {

  height: 100vh;
  background-color:#191919;/* khaki #191919;*/
  color: rgba(255, 255, 255, 0.6);
  overflow: hidden;
  text-align: center;
  min-height: 400px !important;
}

img {
  filter: opacity(.9);
}

img:hover {
  filter: opacity(1);
}

#main div {
  background-color:rgba(146, 60, 60, 0.201);/* red;/*rgba(146, 60, 60, 0.201);*/
}

#main {
 /* width: 400px;*/
  height: 400px;
  background-color: #e4dede78;
  color: rgba(255, 255, 255, 0.6);
  margin: auto;
  font-size: 30px;
  font-weight: bold;
  font-family: tahoma;
  min-height: calc(100vh - 90px);
  overflow-y: scroll;
}

#main::-webkit-scrollbar {
  border: 2px solid #222;
  width: 22px;
}

#main::-webkit-scrollbar-thumb {
  background: #222;
  cursor: pointer;
  border: 2px solid grey;
  border-left: 2px solid #222;
  border-right: 2px solid #111;
  border-top: none;
  border-bottom: none;
  margin-left: 5px;
  margin-right: 5px;
}

#main::-webkit-scrollbar-thumb:hover {
  background: transparent;
  background: linear-gradient(to bottom, rgba(22, 33, 55, 0.4), rgba(22, 33, 55, 0.4), rgba(22, 33, 55, 0.4));
  background: #111;
  cursor: pointer;
  border: 1px solid #222;
  border-top: none;
  border-bottom: none;
}

#main::-webkit-scrollbar-track {
  background: linear-gradient(to bottom, rgba(22, 33, 55, 0.1), rgba(22, 33, 55, 0.1), rgba(22, 33, 55, 0.1));
  border-left: 1px solid #0c0c0c;
}

#main::-webkit-scrollbar-track:hover {
  background: linear-gradient(to bottom, rgba(22, 33, 55, 0.2), rgba(22, 33, 55, 0.2), rgba(22, 33, 55, 0.2));
}

#main #demo {
  text-align: center;
  padding-bottom: 2px;
  z-index: 100;
  width:100%;
  padding:5px auto;
}

#main p {
  text-align: justify;
  padding: 28px 8px;
  margin-bottom: 15px;
  font-family: "Sofia", sans-serif;
  font-size: 22px;
  color: #111 !important;
  /*background:orange !important;*/
}

#header {
  margin-top: 0;
  /*width: 100%;*/
  background-color: #111;
  background: linear-gradient(to bottom, #000, #565555);
  height: 50px;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  border-bottom: 1px solid black !important;
  font-family: "Trirong", serif;
}

#footer {
  margin-top: 0;
  width:100%;
  /*min-width: 400px;*/
  background-color: #111;
  height: 30px;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  border-top: 1px solid black !important;
}

#header a {
  font-size: 22px;
  letter-spacing: 2px;
  color: rgba(4, 4, 13, 0.704);
  text-decoration: none;
  font-weight: bold;
  max-width: 140px;
  min-width: 140px;
  min-height: 40px;
  max-height: 50px;
  padding: 3px 0;
  transition: 1s;
  cursor: grabbing;
  background: linear-gradient(to top, #333, #444, #666);
}

a:hover::first-letter {
  text-shadow: 1px 1px 1px black;
  transition: 2s;
  cursor: pointer;
}

a::first-letter {
  text-shadow: 1px 1px 1px snow;
  transition: 2s;
  cursor: pointer;
  font-size: 25px;
}

#demo {
  padding-top: 2px;
  background: linear-gradient(to bottom, transparent 98%, #000 2%);
  font-size: 40px;
  letter-spacing: 3px;
  visibility: visible;
  height: 40px;
  width:100%;
  padding:5px auto;
}

#footer a {
  font-size: 20px;
  letter-spacing: 1px;
  color: #222;
  text-decoration: none;
  font-weight: bold;
}

.boster {
  border: 12px solid rgba(255, 255, 255, 0.374);
  /*width: 400px;*/
  margin-top: 30px;
  margin-bottom: 10px;
  margin-left: auto;
  margin-right: auto;
}

@media(max-width:500px) {
  .boster {
    width:100%;
    /*min-width: 300px;*/
    margin: auto;
  }

  #header {
    display:flex;
    align-items:center;
    justify-content:space-between;
    border-bottom: 2px solid #000;
    width:100%;/*350px;*/
    min-width:300px;
  }
  #header a {
    font-size: 18px;
    letter-spacing: 2px;
    color: rgba(4, 4, 13, 0.704);
    text-decoration: none;
    font-weight: bold;
    max-width: 110px;
    min-width: 110px;
    min-height: 40px;
    max-height: 50px;
    transition: 1s;
    cursor: grabbing;
    background: linear-gradient(to top, #333, #444, #666);
  }
  #header a:hover {
  letter-spacing: -2px;
  color: #555;
  color: rgba(4, 4, 13, 0.89);
  transition: 2s;
  cursor: grabbing;
  background: linear-gradient(to bottom, rgba(145, 145, 129, 0.483), rgba(119, 119, 193, 0.443), #00000018);
  transform: rotateX(12deg);
}
  a:hover::first-letter {
    text-shadow: 1px 1px 1px black;
    transition: 2s;
    cursor: pointer;
  }
  
  a::first-letter {
    text-shadow: 1px 1px 1px snow;
    transition: 2s;
    cursor: pointer;
    font-size: 25px;
  }
  #main {
    margin: 5px auto;
    padding: 10px auto;
    min-width: 300px;
    height: calc(100vh - 140px);
    height: calc(100vh - 90px);
    font-size: 20px;
    text-align: justify;
    display:flex;
    align-items:center;
    justify-content:space-between;
    flex-direction:column;
  }
  #main::-webkit-scrollbar {
    display:none;
  }
  #main #demo {
    text-align: center;
    font-family: Sofia;
    text-align: center;
    font-family: Sofia;
    min-height: 95px;
    position: sticky;
    top: 0px;
    background:#222222;/*green; #222;*/
    box-sizing:border-box;
    width:100%;
    padding:15px auto;
    min-width:310px !important;
  }

  #main div {
    background-color:rgba(60, 146, 138, 0.201); /*blue; rgba(60, 146, 138, 0.201);*/
    min-height: fit-content;
    box-sizing:border-box;
    width:fit-content;
  }

  #main p {
    text-align: justify;
    padding: 33px 5px;
    box-sizing:border-box;
    font-size:20px;
  }

  #side-right {
    display: none;
    overflow-y: scroll;
    overflow-x: hidden;
    font-family: "Audiowide", sans-serif;
  }

  #side-left {
    display: none;
    overflow-y: scroll;
    overflow-x: hidden;
    font-family: "Audiowide", sans-serif;
  }

  #logo {
    display: none;
  }

  .boster {
    border: 6px solid rgba(255, 255, 255, 0.374);
    width: 100%;
    box-sizing:border-box;
  }
  #footer{
    min-width:300px;
    width:100%;
    margin-bottom:0;
  }
}

@media(min-width:501px) {
  #header {
    border-bottom: 2px solid #111;
    gap: 40px;
  }

  #main {
    padding: 100px auto;
    height: calc(100vh - 140px);
    height: calc(100vh - 90px);
    width: calc(100vw - 50%);
  }

  #main #demo {
    text-align: center;
    font-family: Sofia;
    padding-bottom: 15px;
    min-height: 65px;
    position: sticky;
    top: 0px;
    background: #222;
    width:100%;
  }

  #main p {
    text-align: justify;
    padding: 28px 60px;
    margin-bottom: 15px;
  }

  #side-right {
    display: none;
    overflow: auto;
    direction: rtl;
    overflow-y: scroll;
    overflow-x: hidden;
    line-height: 30px;
    text-align: justify;
    padding: 25px;
    font-size: 30px;
    font-family: "Audiowide", sans-serif;
  }

  #side-left {
    display: none;
    overflow-y: scroll;
    overflow-x: hidden;
    line-height: 30px;
    text-align: justify;
    padding: 25px;
    font-size: 30px;
    font-family: "Audiowide", sans-serif;
  }

  #side-right::-webkit-scrollbar {
    border: 2px solid #222;
    width: 22px;
  }

  #side-left::-webkit-scrollbar {
    border: 2px solid #222;
    width: 22px;
  }

  #side-right::-webkit-scrollbar-thumb {
    /*background: transparent;*/
    background: #222;
    cursor: pointer;
    border: 2px solid grey;
    border-right: 2px solid #222;
    border-left: 2px solid #111;
    border-top: none;
    border-bottom: none;
  }

  #side-left::-webkit-scrollbar-thumb {
    /*background: transparent;*/
    background: #222;
    cursor: pointer;
    border: 2px solid grey;
    border-left: 2px solid #222;
    border-right: 2px solid #111;
    border-top: none;
    border-bottom: none;
    margin-left: 5px;
    margin-right: 5px;
  }

  #side-right::-webkit-scrollbar-thumb:hover {
    background: transparent;
    background: linear-gradient(to bottom, rgba(22, 33, 55, 0.4), rgba(22, 33, 55, 0.4), rgba(22, 33, 55, 0.4));
    background: #111;
    cursor: pointer;
    border: 1px solid #222;
    border-top: none;
    border-bottom: none;
  }

  #side-left::-webkit-scrollbar-thumb:hover {
    background: transparent;
    background: linear-gradient(to bottom, rgba(22, 33, 55, 0.4), rgba(22, 33, 55, 0.4), rgba(22, 33, 55, 0.4));
    background: #111;
    cursor: pointer;
    border: 1px solid #222;
    border-top: none;
    border-bottom: none;
  }

  #side-right::-webkit-scrollbar-track {
    background: linear-gradient(to bottom, rgba(22, 33, 55, 0.1), rgba(22, 33, 55, 0.1), rgba(22, 33, 55, 0.1));
    border-right: 1px solid #0c0c0c;
  }

  #side-left::-webkit-scrollbar-track {
    background: linear-gradient(to bottom, rgba(22, 33, 55, 0.1), rgba(22, 33, 55, 0.1), rgba(22, 33, 55, 0.1));
    border-left: 1px solid #0c0c0c;
  }

  #side-right::-webkit-scrollbar-track:hover {
    background: linear-gradient(to bottom, rgba(22, 33, 55, 0.2), rgba(22, 33, 55, 0.2), rgba(22, 33, 55, 0.2));
  }

  #side-left::-webkit-scrollbar-track:hover {
    background: linear-gradient(to bottom, rgba(22, 33, 55, 0.2), rgba(22, 33, 55, 0.2), rgba(22, 33, 55, 0.2));
  }

}

@media(min-width:900px) {
  #header {
    border-bottom: 2px solid #111;
    gap: 130px;
  }

  #main {
    height: calc(100vh - 90px);
  }

  #main #demo {
    text-align: center;
    font-family: Sofia;
    padding-bottom: 15px;
    min-height: 65px;
    position: sticky;
    top: 0px;
    background: #222;
    width:100%;
  }

  #main p {
    text-align: justify;
    padding: 28px 70px;
    margin-bottom: 15px;
  }

  #side-right {
    display: block;
    width: 23%;
    right: 20px;
    /*background-color: rgba(25, 25, 25, 0.1);*/
    /*background-color: rgba(50, 50, 50, 0.5);*/
    background-color: rgba(194, 194, 194, 0.5);
    position: absolute;
    height: calc(100vh - 140px);
    height: calc(100vh - 90px);
    font-family: fantasy;
    font-size: 23px;
    /*color: #001;*/
    color: rgba(9, 9, 9, 0.927);
    font-family: "Audiowide", sans-serif;
  }

  #side-left {
    display: block;
    width: 23%;
    left: 20px;
    /*background-color: rgba(25, 25, 25, 0.3);*/
    background-color: rgba(194, 194, 194, 0.5);
    position: absolute;
    height: calc(100vh - 140px);
    height: calc(100vh - 90px);
    font-family: fantasy;
    font-size: 23px;
    /*color: #001;*/
    color: rgba(9, 9, 9, 0.927);
    font-family: "Audiowide", sans-serif;
  }

  #logo {
    position: absolute;
    left: 20px;
    display: block;
    z-index: 111;
  }

  #logo:after {
    content: '\00A4';
    font-size: 80px;
    z-index: 111;
  }

}