/* =========================================
   VIDEOS — Estilos específicos
========================================= */

/* ===== NAVBAR VIDEOS ===== */
nav#navbar {
  position: fixed; top: 16px; left: 50%; transform: translateX(-50%);
  width: 94%; max-width: 1200px;
  background: var(--glass-bg); backdrop-filter: blur(24px);
  border: 1px solid var(--glass-border); border-radius: var(--radius-pill);
  padding: 10px 28px; z-index: 1000;
  display: flex; justify-content: space-between; align-items: center;
  transition: all 0.4s ease; box-shadow: var(--shadow);
}
nav#navbar.scrolled { top: 8px; padding: 8px 24px; }
.nav-logo { display: flex; align-items: center; }
.nav-logo img { height: 40px; filter: drop-shadow(0 0 8px rgba(56, 189, 248, 0.3)); transition: height 0.4s; }
nav#navbar.scrolled .nav-logo img { height: 35px; }
.back-to-levels { color: var(--text-primary); font-size: 0.9rem; font-weight: 600; display: flex; align-items: center; gap: 8px; text-decoration: none; transition: color 0.2s; }
.back-to-levels:hover { color: var(--accent); }
.nav-actions { display: flex; align-items: center; gap: 8px; }
.theme-btn { width: 36px; height: 36px; border-radius: 50%; border: 1px solid var(--glass-border); background: var(--glass-bg); color: var(--text-primary); display: flex; align-items: center; justify-content: center; transition: all 0.2s; font-size: 0.9rem; }
.theme-btn:hover { background: var(--accent); color: var(--bg-primary); }

/* ===== HERO ===== */
.hero {
  min-height: 35vh;
  background: radial-gradient(ellipse 80% 60% at 50% -10%, rgba(56, 189, 248, 0.13) 0%, transparent 60%), var(--bg-primary);
  display: flex; flex-direction: column; align-items: center; justify-content: center;
  text-align: center; padding: 100px 40px 30px;
  position: relative; overflow: hidden;
}
.hero h1 {
  font-size: clamp(28px, 5vw, 42px); font-weight: 900; margin-bottom: 8px;
  background: linear-gradient(135deg, var(--text-primary) 0%, var(--accent) 50%, var(--secondary) 100%);
  -webkit-background-clip: text; background-clip: text; color: transparent;
}
.hero p { color: var(--text-secondary); max-width: 520px; line-height: 1.7; }
.stars-bg { position: absolute; inset: 0; pointer-events: none; overflow: hidden; }
.stars-bg span {
  position: absolute; width: 2px; height: 2px;
  background: rgba(255, 255, 255, 0.6); border-radius: 50%;
  animation: twinkle var(--d, 3s) ease-in-out infinite; opacity: 0;
}
@keyframes twinkle {
  0%, 100% { opacity: 0; transform: scale(0.5); }
  50% { opacity: 1; transform: scale(1); }
}

/* ========================================= */
/* LEVEL SELECTOR (COMPACTO) */
/* ========================================= */
.level-selector {
  display: flex;
  gap: 10px;
  justify-content: center;
  margin: 24px auto 8px;
  max-width: 1200px;
  padding: 0 24px;
  flex-wrap: wrap;
}

.level-btn {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 10px 20px;
  background: var(--glass-bg);
  border: 1.5px solid var(--glass-border);
  border-radius: var(--radius-pill);
  text-decoration: none;
  transition: all 0.25s ease;
  backdrop-filter: blur(10px);
}

.level-btn:hover {
  transform: translateY(-2px);
  border-color: var(--accent);
  box-shadow: 0 4px 16px rgba(56,189,248,0.15);
}

.level-btn.active {
  background: rgba(56,189,248,0.15);
  border-color: var(--accent);
  box-shadow: 0 0 20px rgba(56,189,248,0.2);
}

.level-name {
  font-family: 'Poppins', sans-serif;
  font-size: 0.9rem;
  font-weight: 600;
  color: var(--text-primary);
}

.level-subtitle {
  font-family: 'DM Mono', monospace;
  font-size: 0.65rem;
  color: var(--accent);
  letter-spacing: 0.5px;
  text-transform: uppercase;
  opacity: 0.8;
}

[data-theme="light"] .level-btn {
  background: rgba(255,255,255,0.8);
  border-color: rgba(2,132,199,0.2);
}

[data-theme="light"] .level-btn.active {
  background: rgba(2,132,199,0.1);
  border-color: var(--accent);
}

/* ========================================= */
/* SUBUNIT TABS (NUEVO) */
/* ========================================= */
.subunit-tabs {
  display: flex;
  gap: 8px;
  margin: 20px auto 30px;
  max-width: 1200px;
  padding: 0 24px;
  justify-content: center;
  flex-wrap: wrap;
}

.subunit-tab {
  padding: 12px 24px;
  background: var(--glass-bg);
  border: 1px solid var(--glass-border);
  border-radius: 999px;
  font-family: 'DM Mono', monospace;
  font-size: 0.85rem;
  font-weight: 500;
  color: var(--text-secondary);
  cursor: pointer;
  transition: all 0.25s ease;
  text-decoration: none;
  display: inline-flex;
  align-items: center;
  gap: 8px;
  backdrop-filter: blur(10px);
  letter-spacing: 0.5px;
}

.subunit-tab:hover:not(.disabled) {
  background: rgba(56,189,248,0.1);
  border-color: var(--accent);
  color: var(--accent);
  transform: translateY(-2px);
  box-shadow: 0 4px 16px rgba(56,189,248,0.15);
}

.subunit-tab.active {
  background: var(--accent);
  color: var(--bg-primary);
  font-weight: 700;
  border-color: var(--accent);
  box-shadow: 0 4px 20px rgba(56,189,248,0.3);
}

.subunit-tab.disabled {
  opacity: 0.4;
  cursor: not-allowed;
  position: relative;
}

.subunit-tab.disabled::after {
  content: "🚧";
  margin-left: 4px;
  font-size: 0.8rem;
}

.subunit-count {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-width: 22px;
  height: 22px;
  padding: 0 6px;
  border-radius: 999px;
  background: rgba(56,189,248,0.2);
  font-size: 0.75rem;
  font-weight: 700;
}

.subunit-tab.active .subunit-count {
  background: rgba(255,255,255,0.25);
}

.subunit-tab.disabled .subunit-count {
  background: rgba(255,255,255,0.1);
  font-size: 0.65rem;
}

[data-theme="light"] .subunit-tab {
  background: rgba(255,255,255,0.7);
  border-color: rgba(2,132,199,0.2);
  color: rgba(2,6,23,0.6);
}

[data-theme="light"] .subunit-tab:hover:not(.disabled) {
  background: rgba(2,132,199,0.08);
  border-color: var(--accent);
  color: var(--accent);
}

[data-theme="light"] .subunit-tab.active {
  background: var(--accent);
  color: #fff;
}

/* ===== CONTROLS ===== */
.controls { max-width: 1000px; margin: 0 auto; padding: 0 24px; }
.level-tabs { display: flex; gap: 8px; flex-wrap: wrap; justify-content: center; margin: 20px 0 24px; }
.level-tab {
  padding: 10px 20px; border-radius: var(--radius-pill);
  background: var(--glass-bg); border: 1px solid var(--glass-border);
  color: var(--text-secondary); font-weight: 600; cursor: pointer; transition: all 0.2s;
}
.level-tab:hover { border-color: var(--accent); color: var(--text-primary); }
.level-tab.active { background: var(--accent); color: var(--bg-primary); border-color: var(--accent); box-shadow: var(--glow); }

.search-bar { position: relative; max-width: 500px; margin: 0 auto 30px; }
.search-bar input {
  width: 100%; padding: 14px 20px 14px 48px;
  border-radius: var(--radius-pill); background: var(--glass-bg);
  border: 1px solid var(--glass-border); color: var(--text-primary);
  font-size: 1rem; outline: none; transition: border-color 0.3s;
}
.search-bar input:focus { border-color: var(--accent); }
.search-bar i { position: absolute; left: 18px; top: 50%; transform: translateY(-50%); color: var(--text-secondary); }

/* ===== UNITS ACCORDION ===== */
.unit-block { margin-bottom: 16px; background: var(--glass-bg); border: 1px solid var(--glass-border); border-radius: var(--radius-md); overflow: hidden; }
.unit-header {
  padding: 18px 24px; cursor: pointer;
  display: flex; justify-content: space-between; align-items: center;
  transition: background 0.2s; user-select: none;
}
.unit-header:hover { background: rgba(255,255,255,0.03); }
.unit-header h3 { font-size: 1.1rem; color: var(--accent); display: flex; align-items: center; gap: 10px; }
.unit-header i { transition: transform 0.3s; color: var(--text-secondary); }
.unit-block.open .unit-header i { transform: rotate(180deg); }
.unit-content { display: none; padding: 20px 24px; border-top: 1px solid var(--glass-border); background: rgba(0,0,0,0.2); }
.unit-block.open .unit-content { display: block; animation: slideDown 0.3s ease; }
@keyframes slideDown {
  from { opacity: 0; transform: translateY(-10px); }
  to { opacity: 1; transform: translateY(0); }
}

/* ===== VIDEO GRID ===== */
.videos-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(320px, 1fr)); gap: 24px; padding: 20px 0; }
.video-card {
  background: var(--glass-bg); border: 1px solid var(--glass-border);
  border-radius: var(--radius-md); overflow: hidden;
  cursor: pointer; transition: all 0.3s; backdrop-filter: blur(10px);
}
.video-card:hover { transform: translateY(-6px); border-color: var(--accent); box-shadow: 0 12px 40px rgba(56,189,248,0.2); }

.video-thumbnail { position: relative; aspect-ratio: 16/9; overflow: hidden; }
.video-thumbnail img {
  width: 100%; height: 100%; object-fit: cover;
  transition: transform 0.4s;
}
.video-card:hover .video-thumbnail img { transform: scale(1.05); }

.video-play-overlay {
  position: absolute; inset: 0;
  display: flex; align-items: center; justify-content: center;
  background: rgba(0,0,0,0.3); transition: background 0.3s;
}
.video-play-overlay i {
  font-size: 3rem; color: white;
  background: var(--accent); width: 70px; height: 70px;
  border-radius: 50%; display: flex; align-items: center; justify-content: center;
  transition: transform 0.3s;
}
.video-card:hover .video-play-overlay i { transform: scale(1.1); }

.video-number {
  position: absolute; top: 12px; left: 12px;
  background: rgba(0,0,0,0.8); color: white;
  padding: 4px 10px; border-radius: var(--radius-pill);
  font-size: 0.75rem; font-weight: 700; letter-spacing: 0.5px;
}

.video-info { padding: 20px; }
.video-title { font-size: 1.15rem; font-weight: 700; margin-bottom: 8px; color: var(--text-primary); }
.video-description { font-size: 0.9rem; color: var(--text-secondary); line-height: 1.6; }

/* ===== HEADER DE VIDEOS ===== */
.videos-header { text-align: center; margin-bottom: 40px; }
.videos-breadcrumb { font-size: 0.85rem; color: var(--text-secondary); margin-bottom: 12px; }
.videos-breadcrumb a { color: var(--accent); text-decoration: none; }
.videos-breadcrumb a:hover { text-decoration: underline; }
.videos-title {
  font-size: 2.5rem; font-weight: 800; margin-bottom: 8px;
  background: linear-gradient(135deg, var(--text-primary), var(--accent));
  -webkit-background-clip: text; background-clip: text; color: transparent;
}
.videos-subtitle { color: var(--text-secondary); font-size: 1.05rem; }

/* ===== ESTADO "PRÓXIMAMENTE" ===== */
.coming-soon-state {
  text-align: center; padding: 80px 20px;
  background: var(--glass-bg); border: 1px solid var(--glass-border);
  border-radius: var(--radius-lg); backdrop-filter: blur(10px);
  max-width: 600px; margin: 40px auto;
}
.coming-soon-icon {
  font-size: 4rem; margin-bottom: 20px;
  animation: float 3s ease-in-out infinite;
}
@keyframes float {
  0%, 100% { transform: translateY(0); }
  50% { transform: translateY(-10px); }
}
.coming-soon-state h2 { font-size: 1.8rem; color: var(--gold); margin-bottom: 12px; }
.coming-soon-state p { color: var(--text-secondary); line-height: 1.7; max-width: 500px; margin: 0 auto; }
.btn-explore {
  display: inline-flex; align-items: center; gap: 8px;
  margin-top: 24px; padding: 12px 24px;
  background: var(--accent); color: var(--bg-primary);
  border-radius: var(--radius-pill); font-weight: 700;
  text-decoration: none; transition: all 0.3s;
}
.btn-explore:hover { transform: translateY(-2px); box-shadow: 0 8px 25px rgba(56,189,248,0.4); }

/* ===== LOADING & EMPTY STATES ===== */
.loading-state, .empty-state { text-align: center; padding: 60px 20px; color: var(--text-secondary); }
.loading-state i, .empty-state i { font-size: 3rem; margin-bottom: 16px; opacity: 0.5; }
.loading-state { animation: pulse 1.5s infinite; }
@keyframes pulse {
  0%, 100% { opacity: 0.5; }
  50% { opacity: 1; }
}

/* ===== MODAL DE VIDEO ===== */
#videoModal {
    display: none; position: fixed; inset: 0;
    background: rgba(0, 0, 0, 0.92); z-index: 3000;
    align-items: center; justify-content: center; padding: 20px;
}
#videoModal.active { display: flex; }

.modal-video-content {
    background: var(--bg-secondary); border: 1px solid var(--glass-border);
    border-radius: var(--radius-lg); padding: 20px;
    max-width: 960px; width: 100%; position: relative;
    animation: modalVideoIn 0.3s ease;
}
@keyframes modalVideoIn {
    from { opacity: 0; transform: scale(0.95); }
    to { opacity: 1; transform: scale(1); }
}

.modal-video-content .close-modal {
    position: absolute; top: -16px; right: -16px;
    width: 42px; height: 42px;
    background: var(--accent); color: var(--bg-primary);
    border: none; border-radius: 50%; font-size: 1.1rem;
    cursor: pointer; display: flex; align-items: center; justify-content: center;
    z-index: 2; transition: all 0.2s;
    box-shadow: 0 4px 15px rgba(0,0,0,0.4);
}
.modal-video-content .close-modal:hover {
    transform: scale(1.1); background: var(--danger); color: white;
}

.video-wrapper {
    width: 100%; aspect-ratio: 16 / 9;
    border-radius: var(--radius-md); overflow: hidden; background: #000;
}
.video-wrapper iframe { width: 100%; height: 100%; border: none; display: block; }

.modal-video-info { padding: 16px 6px 4px; }
.modal-video-info h3 { font-size: 1.15rem; font-weight: 700; color: var(--accent); margin-bottom: 6px; }
.modal-video-info p { font-size: 0.9rem; color: var(--text-secondary); line-height: 1.6; }

/* ===== RESPONSIVE ===== */
@media (max-width: 768px) {
  body { cursor: auto; }
}
@media (max-width: 760px) {
  .hero { padding: 80px 24px 30px; }
  .videos-grid { grid-template-columns: 1fr; }
  .level-tabs { gap: 4px; }
  .level-tab { padding: 8px 14px; font-size: 0.9rem; }
  .level-selector { gap: 10px; }
  .level-btn { padding: 14px 24px; min-width: 160px; }
  .level-name { font-size: 1.1rem; }
  .subunit-tabs { gap: 6px; padding: 0 16px; }
  .subunit-tab { padding: 10px 16px; font-size: 0.8rem; }
}
@media (max-width: 640px) {
  .modal-video-content { padding: 12px; }
  .modal-video-content .close-modal { top: -12px; right: -12px; width: 38px; height: 38px; }
  .level-selector { flex-direction: column; align-items: center; }
  .level-btn { width: 100%; max-width: 300px; }
}