/* ===============================
   CURSO HTML5 – ESTILOS GENERALES (PRO)
   Autor: Freimel Jerez WebApp
================================ */

:root {
  --bg: #0f172a;
  --card: #111827;
  --text: #e5e7eb;
  --muted: #9ca3af;
  --primary: #22c55e;
  --border: #1f2933;
  --code-bg: #020617;
}

/* ================= RESET ================= */
* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: system-ui, -apple-system, BlinkMacSystemFont, sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.7;
}

/* ================= CONTENEDOR ================= */
.container {
  max-width: 1000px; /* un poco más ancho para el index */
  margin: auto;
  padding: 24px;
}

/* ================= HEADER ================= */
.topbar {
  background: #020617;
  border-bottom: 1px solid var(--border);
}

.brand {
  color: var(--primary);
  text-decoration: none;
  font-weight: 700;
}

/* ================= ARTÍCULO ================= */
.post {
  background: var(--card);
  padding: 32px;
  border-radius: 14px;
  margin-top: 24px;
}

.post h1,
.post h2,
.post h3 {
  color: #fff;
  margin-top: 28px;
}

.muted {
  color: var(--muted);
}

.post-img {
  width: 100%;
  border-radius: 12px;
  margin: 24px 0;
}

/* ================= CÓDIGO ================= */
pre {
  background: var(--code-bg);
  padding: 16px;
  border-radius: 12px;
  overflow-x: auto;
  margin: 20px 0;
}

code {
  color: #22d3ee;
  font-family: Consolas, monospace;
  font-size: 14px;
}

/* ================= VIDEO ================= */
.video-wrapper {
  position: relative;
  padding-bottom: 56.25%;
  height: 0;
  overflow: hidden;
  border-radius: 14px;
  margin: 24px 0;
  background: #000;
}

.video-wrapper iframe {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  border: 0;
}

/* ================= BOTÓN VOLVER ================= */
.back {
  display: inline-block;
  margin: 12px 0 18px;
  color: var(--primary);
  text-decoration: none;
  font-weight: 600;
}

.back:hover {
  text-decoration: underline;
}

/* ================= NAVEGACIÓN DE LECCIÓN ================= */
.course-nav {
  margin-top: 40px;
  padding-top: 24px;
  border-top: 1px solid var(--border);
  text-align: center;
}

.course-nav button {
  padding: 14px 28px;
  font-size: 16px;
  font-weight: bold;
  border-radius: 10px;
  border: none;
  cursor: not-allowed;
  background: #374151;
  color: #9ca3af;
  transition: all 0.3s ease;
}

.course-nav button.enabled {
  background: var(--primary);
  color: #020617;
  cursor: pointer;
}

.course-nav button.enabled:hover {
  background: #16a34a;
  transform: translateY(-2px);
}

/* ================= LISTA DEL CURSO (GRID) ================= */
.course-list {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 20px;
  margin-top: 32px;
}

/* ================= TARJETA DE LECCIÓN ================= */
.lesson {
  display: grid;
  grid-template-columns: auto 1fr auto;
  gap: 14px;
  align-items: center;

  background: #020617;
  border: 1px solid var(--border);
  border-radius: 14px;
  padding: 18px;

  color: var(--text);
  text-decoration: none;
  transition: transform 0.25s ease, box-shadow 0.25s ease;
}

/* Número */
.lesson .num {
  font-size: 22px;
  font-weight: 800;
  color: var(--primary);
}

/* Texto */
.lesson strong {
  display: block;
  font-size: 15px;
}

.lesson small {
  display: block;
  color: var(--muted);
  font-size: 13px;
  margin-top: 2px;
}

/* Estado */
.lesson .status {
  font-size: 14px;
  white-space: nowrap;
}

/* DESBLOQUEADA */
.lesson.unlocked {
  border-color: #22c55e55;
}

.lesson.unlocked:hover {
  transform: translateY(-4px);
  box-shadow: 0 14px 40px rgba(0,0,0,.45);
}

/* BLOQUEADA */
.lesson.locked {
  opacity: 0.55;
  cursor: not-allowed;
}

/* ================= PROYECTO FINAL ================= */
.lesson.final {
  grid-column: 1 / -1;
  background: linear-gradient(135deg, #022c22, #020617);
  border-color: #22c55e;
}

.lesson.final .num {
  color: #34d399;
}

/* ================= FOOTER ================= */
.footer {
  text-align: center;
  margin-top: 48px;
  color: var(--muted);
  font-size: 14px;
}

/* ================= ADSENSE ================= */
.adsbygoogle {
  margin: 32px auto;
  border-radius: 12px;
  overflow: hidden;
}

/* ================= RESPONSIVE ================= */
@media (max-width: 600px) {
  .post {
    padding: 20px;
  }

  .lesson {
    grid-template-columns: auto 1fr;
  }

  .lesson .status {
    grid-column: 1 / -1;
    text-align: right;
    margin-top: 8px;
  }

  .course-nav button {
    width: 100%;
  }
}

/* ================= MENÚ HAMBURGUESA ================= */
.header-flex {
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.hamburger {
  display: none;
  font-size: 26px;
  background: none;
  border: none;
  color: var(--text);
  cursor: pointer;
}

.nav {
  display: flex;
  gap: 18px;
}

.nav a {
  color: var(--text);
  text-decoration: none;
  font-weight: 600;
}

.nav a:hover {
  color: var(--primary);
}

/* MÓVIL */
@media (max-width: 768px) {
  .hamburger {
    display: block;
  }

  .nav {
    position: absolute;
    top: 64px;
    left: 0;
    width: 100%;
    background: #020617;
    flex-direction: column;
    padding: 20px;
    display: none;
  }

  .nav.open {
    display: flex;
  }
}