html {
    scroll-behavior: smooth;
}

 :root {
    --azul-neon: #00ffff;
    --azul: #007bff;
    --azul-oscuro: #003366;
    --gris-claro: #f5f5f5;
    --blanco: #ffffff;
    --negro-texto: #1a1a1a;
    --font-principal: 'Poppins', sans-serif;
    --font-secundaria: 'Lato', sans-serif;
    --sombra-suave: 0 2px 5px rgba(0, 0, 0, 0.1);
    --borde-redondeado: 8px;
  }

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


  
  header {
    background-color: var(--azul-oscuro);
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 0 50px;
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    box-shadow: 0px 2px 6px var(--negro-texto);
  }

  .logo_tml img {
    max-width: 160px;
  }

  .logo_tml_movil {
      opacity: 0;
  }

  .contact_info {
    display: flex;
    align-items: center;
    gap: 20px;
  }

  .contact_btn {
    background-color: var(--azul-oscuro);
    border: solid 1px var(--blanco);
    border-radius: 30px;
    box-shadow: 0px 2px 4px var(--azul-neon);
    width: 50px;
    height: 40px;
    text-align: center;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: transform 0.3s ease;
  }

  .contact_btn:hover {
    transform: scale(1.1);
  }

  .contact_info p {
    color: white;
    font-family: var(--font-principal);
  }

  .nav-container {
    display: flex;
  }

    .nav-container nav {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 20px;
  }


  .nav-container.active {
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    position: fixed;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
    background-color: rgba(0, 0, 0, 0.95);
    z-index: 999;
  }

  .nav-container nav ul {
    list-style: none;
    display: flex;
    gap: 20px;
  }

  .nav-container nav ul li a {
    font-family: var(--font-principal);
    color: white;
    text-decoration: none;
    font-size: 1.2rem;
    transition: color 0.3s ease;
  }

  .nav-container nav ul li a:hover {
    color: var(--azul-neon);
    text-decoration: underline;
  }

  #menu-toggle, #menu-close {
    display: none;
    background: none;
    border: none;
    font-size: 2rem;
    color: var(--azul-neon);
    cursor: pointer;
  }

@media (max-width: 1200px) {

  .nav-container {
    display: none; /* ocultar menú */
    position: fixed;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
    background-color: rgba(0,0,0,0.95);
    flex-direction: column;
    justify-content: center;
    align-items: center;
    z-index: 999;
  }

  .logo_tml {
    display: none;
  }

  .logo_tml_movil {
    opacity: 1;
    padding: 8px 0px 0px 0px;
  }

  .nav-container.active {
    display: flex;
  }

  .nav-container nav {
  display: flex;
  flex-direction: column;
  align-items: center; 
  gap: 25px; 
  text-align: center;
}

  .nav-container nav ul {
    flex-direction: column;
    gap: 25px;
  }

  /* Botón toggle visible en móvil */
  #menu-toggle {
    display: block;
  }

  /* Botón cerrar menú visible en móvil */
  #menu-close {
    display: block;
    position: absolute;
    top: 30px;
    right: 30px;
    background: none;
    border: none;
    font-size: 2rem;
    color: var(--azul-neon);
    cursor: pointer;
  }

 .contact_info p {
    display: none;
  }
}

  .visuallyhidden {
  position: absolute !important;
  width: 1px; 
  height: 1px; 
  padding: 0; 
  margin: -1px; 
  overflow: hidden; 
  clip: rect(0, 0, 0, 0); 
  white-space: nowrap; /* Evita que el texto se envuelva */
  border: 0;
  font-size: 2em;
}


/* Sección cursos */

.intro_cursos {
    text-align: center;
    font-family: var(--font-principal);
    max-width: 1200px;
    margin: 140px auto 40px;
}

.intro_cursos h2 {
    color: #003366;
    font-size: 2em;
    margin-bottom: 20px;
}


.cursos_container {
  display: flex;
  max-width: 1200px;
  margin: 20px auto;
  gap: 2rem;
  font-family: 'Poppins', sans-serif;
  color: #1d2b53;
  min-height: 600px;
  z-index: 10;
}

.nav_cursos {
  position: sticky;
  top: 100px;
  flex: 0 0 250px;
  background-color: #f9faff;
  border-radius: 10px;
  padding: 1.5rem 1.2rem;
  box-shadow: 0 4px 12px rgb(29 43 83 / 0.1);
  overflow-y: visible;
  transition: transform 0.3s ease;
  z-index: 10;
  max-height: calc(100vh - 120px);
}

.bandera_inglaterra {
    display: block;
    width: 100%;
    height: auto;
}

.nav_cursos h2 {
  font-size: 1.4rem;
  margin-bottom: 1rem;
  color: #003366;
  font-weight: 700;
  border-bottom: 2px solid #0077cc;
  padding-bottom: 0.4rem;
}

.nav_cursos ul {
  list-style: none;
  padding-left: 0;
  margin: 0;
  position: sticky;
  top: 100px;
  max-height: calc(100vh - 120px);
  overflow-y: auto;
  padding-right: 0.5rem;
}

.nav_cursos li {
  margin-bottom: 0.9rem;
}

.nav_cursos a {
  text-decoration: none;
  color: #1d2b53;
  font-weight: 600;
  font-size: 1rem;
  display: inline-block;
  padding: 0.3rem 0.5rem;
  border-radius: 6px;
  transition: background-color 0.3s ease, color 0.3s ease;
}

.nav_cursos a:hover,
.nav_cursos a:focus {
  background-color: #0077cc;
  color: white;
  outline: none;
}

/* Contenido principal cursos */
.curso_section {
  flex: 1;
  background-color: #fff;
  border-radius: 12px;
  padding: 2rem;
  box-shadow: 0 6px 18px rgb(29 43 83 / 0.1);
  margin-bottom: 3rem;
  scroll-margin-top: 110px; /* para evitar que header tape */
}

.curso_section img {
  max-width: 100%;
  border-radius: 10px;
  margin-bottom: 1rem;
  box-shadow: 0 4px 15px rgb(0 0 0 / 0.1);
  aspect-ratio: 3 / 2;
}

.curso_section h2 {
  font-size: 2rem;
  margin-bottom: 0.6rem;
  color: #003366;
}

.curso_section p {
  font-size: 1.1rem;
  line-height: 1.6;
  margin-bottom: 1rem;
  color: #333;
}

.curso_section details {
  border-top: 1px solid #ddd;
  padding: 1rem 0;
  font-size: 1rem;
  color: #444;
}

.curso_section details summary {
  display: flex;
  align-items: center; /* centra verticalmente la flecha y el texto */
  cursor: pointer;
  font-weight: 700;
  padding-left: 1rem;
  color: #0077cc;
  outline-offset: 4px;
  list-style: none; /* quitar el marcador por defecto */
}

.curso_section details summary::-webkit-details-marker {
  display: none; /* ocultar marcador nativo */
}

.curso_section details summary::before {
  content: "▶";
  margin-right: 0.6rem;
  transition: transform 0.3s ease;
  color: #0077cc;
  flex-shrink: 0; /* para que la flecha no se reduzca */
  font-weight: 700;
}

.curso_section details[open] summary::before {
  transform: rotate(90deg);
}

.curso_section ul {
  list-style: disc inside;
  margin-top: 0.5rem;
  padding-left: 1rem;
  color: #555;
}

summary {
    list-style: none;
}

/* Responsive: móvil */

@media (max-width: 768px) {
  .cursos_container {
    flex-direction: column;
    margin: 40px 1rem 40px;
  }

  .intro_cursos {
    margin-top: 100px;
    padding: 0px 20px 0px 20px;
}

  .nav_cursos {
    position: relative;
    top: auto;
    height: auto;
    flex: none;
    margin-bottom: 1.5rem;
    box-shadow: none;
    text-align: center;
  }

    .nav_cursos ul {
    position: sticky;
  }

  .curso_section {
    margin-bottom: 2rem;
    scroll-margin-top: 70px;
  }
}


/*INICIO FOOTER */

.footer_tml {
  background-color: var(--azul-oscuro);
  color: white;
  font-family: var(--font-principal);
  padding: 30px 20px 10px 20px;
  margin-top: 60px;
}

.footer_container {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  align-items: center;
  max-width: 1200px;
  margin: auto;
  gap: 30px;
}

.footer_logo img {
  border-radius: 10px;
}

.footer_links ul {
  list-style: none;
  padding: 0;
  margin: 0;
  text-align: center;
}

.footer_links li {
  margin: 8px 0;
}

.footer_links a {
  color: white;
  text-decoration: none;
  transition: color 0.3s ease;
}

.footer_links a:hover {
  color: var(--azul-neon);
}

.footer_social a {
  margin: 0 10px;
  display: inline-block;
}

.footer_copy {
  text-align: center;
  font-size: 0.9rem;
  margin-top: 30px;
  color: #aaa;
}

.footer_nav,
.footer_links,
.footer_social {
  text-align: center;
}

.footer_nav h3,
.footer_links h3,
.footer_social h3 {
  margin-bottom: 10px;
  color: var(--azul-neon);
  font-size: 1rem;
}

.footer_nav ul,
.footer_links ul {
  list-style: none;
  padding: 0;
  margin: 0;
}

.footer_nav li,
.footer_links li {
  margin: 5px 0;
}

.footer_nav a,
.footer_links a {
  color: white;
  text-decoration: none;
  font-size: 0.95rem;
  transition: color 0.3s ease;
}

.footer_nav a:hover,
.footer_links a:hover {
  color: var(--azul-neon);
}


@media (max-width: 768px) {
  .footer_container {
    flex-direction: column;
    text-align: center;
    gap: 40px;
    padding: 20px 10px;
  }

  .footer_nav,
  .footer_links,
  .footer_social {
    width: 100%;
  }

  .footer_nav ul,
  .footer_links ul {
    padding-inline: 0;
  }

  .footer_nav li,
  .footer_links li {
    margin: 8px 0;
  }

  .footer_social a img {
    width: 28px;
    height: 28px;
  }

  .footer_copy {
    font-size: 0.85rem;
    padding: 0 10px;
    margin-top: 20px;
  }
}

@media (max-width: 480px) {
  .footer_nav a,
  .footer_links a {
    font-size: 0.9rem;
  }

  .footer_nav h5,
  .footer_links h5,
  .footer_social h5 {
    font-size: 0.95rem;
  }
}