.btn-3d {
	padding: .01rem 1rem;
	border: 1px solid #770b0b;
	border-radius: 6px;
	background-color: #d90b0b;
	color: #fff;
  
	font-size: 1.5rem;
	text-shadow: 0 -1px 0 rgba(0,0,0,.5);
	box-shadow: 0 1px 0 rgba(255,255,255,.5) inset,
	  0 1px 3px rgba(0,0,0,.2);
	background-image: -webkit-gradient(linear,left top,left bottom,color-stop(10%,#f90),to(#e76a00));
	background-image: linear-gradient(#d90b0b 10%,#770b0b 50%);
  }
  
  .btn-3d:hover, .btn-3d:focus {
	background-color: #d90b0b;
	background-image: -webkit-gradient(linear,left top,left bottom,color-stop(10%,#f0a100),to(#f70));
	background-image: linear-gradient(#f0a100 10%,#f70 50%);
  }
  
  .btn-3d:active {
	background-color: #d90b0b;
	box-shadow: 0 2px 3px 0 rgba(0,0,0,.2) inset;
	background-image: -webkit-gradient(linear,left top,left bottom,color-stop(10%,#f0a100),to(#f70));
	background-image: linear-gradient(#f0a100 10%,#f70 50%);
  }



  

.enlaceboton {    font-family: verdana, arial, sans-serif;
	font-size: 12pt;
	font-weight: bold;
	padding: 1px;
	background-color: #ffd000;
	color: #000000;
	text-decoration: none;
 }
 .enlaceboton:link,
 .enlaceboton:visited {
	border-top: 3px solid #cccccc;
	border-bottom: 3px solid #666666;
	border-left: 3px solid #cccccc;
	border-right: 3px solid #666666;
 }
 .enlaceboton:hover {
	border-bottom: 3px solid #666666;
	border-top: 3px solid #666666;
	border-right: 3px solid #cccccc;
	border-left: 3px solid #666666;
 }



 .modo2 {
	
	position: relative;
	top: 180px;
	margin: auto;
	font-size: 25px;
	font-weight:bold;
	background-color:#ff00002f;
	background-image: "";
	background-repeat: repeat-x;
	color: #ffffff;
	font-family: “Trebuchet MS”, Arial;
	text-align:left;
	border: #ffffff;
	border-style: solid;
	z-index: 0;
	
	}
	.modo2 td {
	position: relative;
	top: initial;
	padding: 10px;
	border-right-width: 2px;
	border-bottom-width: 2px;
	border-right-style: solid;
	border-bottom-style: solid;
	border-right-color: rgb(255, 255, 255);
	border-bottom-color: rgb(255, 255, 255);
	z-index: 0;
	}
	.modo2 tr {
	background-image: "";
	background-position: center top;
	font-size: 12px;
	font-weight:bold;
	background-color:rgb(0, 0, 0);
	background-repeat: repeat-x;
	color: #ffffff;
	font-family: “Trebuchet MS”, Arial;
	text-align:center;
	border-right-width: 1px;
	border-bottom-width: 1px;
	border-right-style: solid;
	border-bottom-style: solid;
	border-right-color: #EBE9BC;
	border-bottom-color: #EBE9BC;
	background-image: -webkit-gradient(linear,left top,left bottom,color-stop(10%,#f90),to(#e76a00));
	background-image: linear-gradient(#000000 10%,#ffffff2f 50%);
	z-index: 0;
	}




	div.a{

    	text-align: center;
		text-shadow: 2px 3px #999;
		font-family: verdana;
		color:#ff00002f;
		z-index: 0;
	}

	div.b{

		text-align: center;
		font-family: arial;
		color:black;
		z-index: 0;

	}

	.tdlabel {
		background-color:rgb(255, 255, 255);
		text-align: left;
		font-family: arial;
		color:rgb(0, 0, 0);
		font-size: 18px;
		border-right-color: rgb(0, 0, 0);
		z-index: 0;
		
	}


/*comienza cinta superior*/



	body {
		width:100%;
		
		margin: 0;
		padding: 0;
		font-family: Helvetica, Arial, sans-serif;
		color: #666;
		background: #f2f2f2; 
		font-size: 1em;
		line-height: 1.5em;
	}
	
	h1 {
		font-size: 2.3em;
		line-height: 1.3em;
		margin: 15px 0;
		text-align: center;
		font-weight: 300;
	}
	
	p {
		margin: 0 0 1.5em 0;
	}
	
	
	Estas líneas de CSS las usaremos para dar estilo a la cabecera:
	
	#main-header {
		background: red;
		color: red;
		height: 80px;
	}	
		#main-header a {
			color: rgb(255, 255, 255);
		}
	
	/*
	 * Logo
	 */
	#logo-header {
		float: left;
		padding: 15px 0 0 20px;
		text-decoration: none;
	}
		#logo-header:hover {
			color:  #b13f3f;
		}
		
		#logo-header .site-name {
			display: block;
			font-weight: 700;
			font-size: 1.2em;
		}
		
		#logo-header .site-desc {
			display: block;
			font-weight: 300;
			font-size: 0.8em;
			color: rgb(255, 255, 255);
		}
		
	
	/*
	 * Navegación
	 */
	nav {
		float: right;
	}
		nav ul {
			margin: 0;
			padding: 0;
			list-style: none;
			padding-right: 20px;
		}
		
			nav ul li {
				display: inline-block;
				line-height: 80px;
			}
				
				nav ul li a {
					display: block;
					padding: 0 10px;
					text-decoration: none;
				}
				
					nav ul li a:hover {
						background: #b13f3f;
					}
	Con estos estilos aplicaremos diseño al contenido:
	
	#main-content {
		background: white;
		width: 90%;
		max-width: 800px;
		margin: 20px auto;
		box-shadow: 0 0 10px rgba(0,0,0,.1);
	}
	
		#main-content header,
		#main-content .content {
			padding: 40px;
		}
	Y por último, con esto estilizaremos el pie de página:
	
	#main-footer {
		background: #333;
		color: white;
		text-align: center;
		padding: 20px;
		margin-top: 40px;
	}
		#main-footer p {
			margin: 0;
		}
		
		#main-footer a {
			color: white;
		}
		
		#main-header {
			background: rgb(0, 0, 0);
			background-image: -webkit-gradient(linear,left top,left bottom,color-stop(10%,#f90),to(#e76a00));
			background-image: linear-gradient(#000000 10%,#ff00002f 50%);
			color: white;
			height: 80px;
			
			position: fixed; /* Hacemos que la cabecera tenga una posición fija */
			width: 100%; /* hacemos que la cabecera ocupe el ancho completo de la página */
			left: 0; /* Posicionamos la cabecera al lado izquierdo */
			top: 0; /* Posicionamos la cabecera pegada arriba */
			z-index: 2;
			
		}


	.warnings{
		width: 200px;
		text-align: center;
		margin: auto;
		color: #b13f3f;
		padding-top: 20px;
	}