*{
    margin: 0;
    padding: 0;
}
*,*::before,*::after{
    box-sizing: border-box;
}
body{
    font-family: 'Lucida Sans', 'Lucida Sans Regular', 'Lucida Grande', 'Lucida Sans Unicode', Geneva, Verdana, sans-serif;
    color:rgb(36, 53, 86);
    line-height: 1.6;
}
#logo{
    color: rgb(37, 34, 92);
    font-size: 1.8rem;
}
#logo span{
    color: rgb(255, 214, 79);
}
.subtitulo{
    color: rgb(27, 28, 79);
}

.banner-oferta{
    background-color: rgb(255, 137, 59);
    color: white;
    text-align: center;
    padding: 10px 15px;
    border-bottom: 3px solid rgb(152, 121, 69);
    font-weight: bold;
    font-size: 0.9rem;
    position: sticky;
    top: 0;
    z-index: 100;
}
 
.tarjeta-curso{
    background-color: rgb(252, 251, 239);
    width: 100%;
    max-width: 350px;
    padding: 25px;
    margin: 15px 0;
    border: 1px solid cornflowerblue;
}
.tarjeta-curso h3{
    font-size: 1.4rem;
    color: rgb(27, 27, 137);
    margin-top: 10px;
}
.precio{
    display: inline-block;
    margin-top: 15px;
    font-size: 1.2rem;
    font-weight: bold;
    color: red;
}

.encabezado-principal{
    background-color: white;
    padding: 15px;
    border-bottom: 1px solid coral;
    display: flex;
    justify-content: space-between;
    align-items: center;
}
.menu-nav ul{
    list-style: none;
    display: flex;
    gap: 20px;
}
.menu-nav a{
    text-decoration: none;
    color: #2c3e50;
    font-weight: 600;
}

.seccion-cursos{
    padding: 40px 5%;
}

.grid-cursos{
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 25px;  
    margin-top: 20px;
}   

@media (max-width: 768px){
    .encabezado-principal{
        flex-direction: column;
        gap:15 px;
        text-align: center;
    }
    .hero h2{
        font-size: 1.5rem;
    }
    .grid-cursos{
        grid-template-columns: 1fr;
    }

}

.hero{
    background: linear-gradient(135deg, #2c3e50,#3498db);
    color: #ffffff;
    padding: 60px 20px;
    text-align: center;
}
.hero h2{
    color: #ffffff;
}
.hero .subtitulo{
    color: #ecf0f1;
}

.tarjeta-curso{
    border-radius: 8px;
    box-shadow: 0 4px 6px rgba(0,0,0,0.5);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.tarjeta-curso:hover{
    transform: translateY(-8px);
    box-shadow: 0 12px 20px rgba(0,0,0,0.5);
}

.tarjeta-curso{
    border: 2px solid #3498db;
}   
.tarjeta-curso p{
    font-size: 1.4rem;
    color: #192c39;
}
#destacado{
    border: 2px solid crimson;
    position: relative;
}
/* Etiqueta de destacados*/
 #destacado:before{
    content: "MÁS POPULAR";
    position: absolute;
    top: -12px;
    right: 12px;
    background-color: red;
    color: #ecf0f1;
}

.btn-principal{
    background-color: #289f4c;
    color: #ffffff;
    border: none;
    padding: 15px 25px;
    font-size: 1rem;
    font-weight: bold;
    border-radius: 5px;
    margin-top: 15px;
    transition: background-color 0px;
}
.btn-principal:hover{
    background-color: aqua;
}
.btn-principal:focus{
    outline: 3px solid rgb(36, 128, 50);
}

.pie-pagina{
    background-color: #1d3647;
    color: #ffffff;
    text-align: center;
    padding: 20px;
    margin-top: 40px;
}