Changer le style du scroll bar in html

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   <title>CHANGER LE STYLE DU SCROLL BAR IN HTML | Par NGLESSON</title>
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   <meta name="author" content="Mezgani said">
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   <link href="style.css" rel="stylesheet" type="text/css">
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      Sed si ille hac tam eximia fortuna propter utilitatem rei publicae frui non properat, 
      ut omnia illa conficiat, quid ego, senator, facere debeo, quem, etiamsi ille aliud vellet, rei publicae consulere oporteret?
      Quare hoc quidem praeceptum, cuiuscumque est, ad tollendam amicitiam valet; illud potius praecipiendum fuit, ut eam diligentiam
      adhiberemus in amicitiis comparandis, ut ne quando amare inciperemus eum, quem aliquando odisse possemus. 
      Quin etiam si minus felices in diligendo fuissemus, ferendum id Scipio potius quam inimicitiarum tempus cogitandum putabat.
      Alii nullo quaerente vultus severitate adsimulata patrimonia sua in inmensum extollunt, cultorum ut puta feracium multiplicantes 
      annuos fructus, quae a primo ad ultimum solem se abunde iactitant possidere, ignorantes profecto maiores suos, per quos ita magnitudo 
      Romana porrigitur, non divitiis eluxisse sed per bella saevissima, nec opibus nec victu nec indumentorum vilitate gregariis militibus 
      discrepantes opposita cuncta superasse virtute.
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::-webkit-scrollbar {
  width: 12px;
}
::-webkit-scrollbar-track {
  box-shadow: inset 0 0 6px rgba(0,0,0,0.3); 
  -webkit-box-shadow : inset 0 0 6px rgba(0,0,0,0.3); 
  -moz-box-shadow : inset 0 0 6px rgba(0,0,0,0.3); 
  border-radius: 10px;
  -webkit-border-radius: 10px;
  -moz-border-radius: 10px;
  -ms-border-radius: 10px;
  -o-border-radius: 10px;
  -khtml-border-radius: 10px;
}
::-webkit-scrollbar-thumb {
  border-radius: 10px;
  -webkit-border-radius: 10px;
  -moz-border-radius: 10px;
  -ms-border-radius: 10px;
  -o-border-radius: 10px;
  -khtml-border-radius: 10px;
  box-shadow: inset 0 0 6px rgba(0,0,0,0.5); 
  -webkit-box-shadow : inset 0 0 6px rgba(0,0,0,0.5); 
  -moz-box-shadow : inset 0 0 6px rgba(0,0,0,0.5);  
}
::-moz-scrollbar {
  width: 12px;
}
::-moz-scrollbar-track {
  box-shadow: inset 0 0 6px rgba(0,0,0,0.3); 
  -webkit-box-shadow : inset 0 0 6px rgba(0,0,0,0.3); 
  -moz-box-shadow : inset 0 0 6px rgba(0,0,0,0.3); 
  border-radius: 10px;
  -webkit-border-radius:10px;
  -moz-border-radius:10px;
  -khtml-border-radius:10px;
}
::-moz-scrollbar-thumb {
  border-radius: 10px;
  -webkit-border-radius:10px;
  -moz-border-radius:10px;
  -khtml-border-radius:10px;
  box-shadow: inset 0 0 6px rgba(0,0,0,0.5); 
  -webkit-box-shadow : inset 0 0 6px rgba(0,0,0,0.5); 
  -moz-box-shadow : inset 0 0 6px rgba(0,0,0,0.5);  
}
::-o-scrollbar {
  width: 12px;
}
::-o-scrollbar-track {
  box-shadow: inset 0 0 6px rgba(0,0,0,0.3); 
  -webkit-box-shadow : inset 0 0 6px rgba(0,0,0,0.3); 
  -moz-box-shadow : inset 0 0 6px rgba(0,0,0,0.3);  
  border-radius: 10px;
  -webkit-border-radius:10px;
  -moz-border-radius:10px;
  -khtml-border-radius:10px;
}
::-o-scrollbar-thumb {
  border-radius: 10px;
  -webkit-border-radius: 10px;
  -moz-border-radius: 10px;
  -ms-border-radius: 10px;
  -o-border-radius: 10px;
  -khtml-border-radius: 10px;
  box-shadow: inset 0 0 6px rgba(0,0,0,0.5); 
  -webkit-box-shadow : inset 0 0 6px rgba(0,0,0,0.5); 
  -moz-box-shadow : inset 0 0 6px rgba(0,0,0,0.5);  
}


.main{
  width: 400px;
  height: 150px;
  overflow-y: scroll;
  margin: 80px 80px;
}