/* Apps hub navigation — shared across zened apps (apps.zenedinstitute.org) */

:root {
  --apps-nav-h: 2.75rem;
}

#apps-nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  height: var(--apps-nav-h);
  display: flex;
  align-items: stretch;
  z-index: 10000;
  background: rgba(13, 27, 33, 0.94);
  border-bottom: 1px solid rgba(74, 158, 143, 0.18);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  font-family: var(--font-zh, "Noto Serif TC", Georgia, serif);
}

#apps-nav .apps-nav-hub,
#apps-nav .apps-nav-back {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.3rem;
  min-height: var(--apps-nav-h);
  min-width: 44px;
  padding: 0 0.9rem;
  font-size: 0.72rem;
  letter-spacing: 0.07em;
  line-height: 1.2;
  text-decoration: none;
  border: none;
  background: none;
  cursor: pointer;
  color: rgba(154, 173, 184, 0.88);
  transition: color 0.2s, background 0.2s;
  white-space: nowrap;
  -webkit-tap-highlight-color: transparent;
}

#apps-nav .apps-nav-hub:hover,
#apps-nav .apps-nav-back:hover,
#apps-nav .apps-nav-hub:focus-visible,
#apps-nav .apps-nav-back:focus-visible {
  color: #4a9e8f;
  background: rgba(74, 158, 143, 0.08);
  outline: none;
}

#apps-nav .apps-nav-en {
  opacity: 0.62;
  font-size: 0.66rem;
  letter-spacing: 0.04em;
}

#apps-nav .apps-nav-back {
  border-left: 1px solid rgba(74, 158, 143, 0.14);
}

#apps-nav .apps-nav-back.is-hidden {
  display: none;
}

body.has-apps-nav {
  padding-top: var(--apps-nav-h);
}

body.has-apps-nav {
  overflow-x: hidden;
}

body.has-apps-nav img,
body.has-apps-nav svg,
body.has-apps-nav canvas {
  max-width: 100%;
}

body.has-apps-nav .screen {
  top: var(--apps-nav-h);
  height: calc(100% - var(--apps-nav-h));
}

body.has-apps-nav #landing {
  min-height: calc(100vh - var(--apps-nav-h));
}

/* Offset fixed UI below nav bar */
body.has-apps-nav #progress-bar {
  top: var(--apps-nav-h);
}

body.has-apps-nav #module-label {
  top: calc(var(--apps-nav-h) + 0.5rem);
}

body.has-apps-nav #lang-btn,
body.has-apps-nav .lang-toggle {
  top: calc(var(--apps-nav-h) + 0.35rem);
}

body.has-apps-nav .topbar {
  top: var(--apps-nav-h);
}

body.has-apps-nav #sidenav {
  top: var(--apps-nav-h);
  padding-top: 1.25rem;
}

body.has-apps-nav #back-btn {
  display: none !important;
}

body.has-apps-nav .sb-back,
body.has-apps-nav .sn-back {
  display: none !important;
}

@media (max-width: 480px) {
  :root {
    --apps-nav-h: 3rem;
  }

  #apps-nav {
    overflow-x: auto;
    -webkit-overflow-scrolling: touch;
  }

  #apps-nav .apps-nav-hub,
  #apps-nav .apps-nav-back {
    padding: 0 0.65rem;
    font-size: 0.68rem;
  }

  #apps-nav .apps-nav-en {
    display: none;
  }
}

@media (max-width: 560px) {
  body.has-apps-nav #sidenav {
    top: auto;
    bottom: 0;
  }
}