/**
 * TeamsApp navigation bar — professional back control, phone + desktop.
 */

.teamsapp-mobile-top-bar {
  --ts-nav-bg: rgba(12, 12, 12, 0.94);
  --ts-nav-border: rgba(212, 0, 0, 0.35);
  --ts-nav-text: #ffffff;
  --ts-nav-muted: rgba(255, 255, 255, 0.72);
  --ts-nav-btn-bg: rgba(255, 255, 255, 0.08);
  --ts-nav-btn-border: rgba(255, 255, 255, 0.12);
  --ts-nav-btn-hover: rgba(255, 255, 255, 0.14);
  --ts-nav-height: 56px;
  --ts-nav-touch: 44px;

  display: grid;
  grid-template-columns: minmax(0, 1fr) auto minmax(0, 1fr);
  align-items: center;
  column-gap: 12px;
  min-height: var(--ts-nav-height);
  padding: 8px 16px;
  padding-top: max(8px, env(safe-area-inset-top, 0px));
  padding-left: max(16px, env(safe-area-inset-left, 0px));
  padding-right: max(16px, env(safe-area-inset-right, 0px));
  background: var(--ts-nav-bg);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  border-bottom: 1px solid var(--ts-nav-border);
  box-shadow: 0 4px 24px rgba(0, 0, 0, 0.28);
  position: sticky;
  top: 0;
  z-index: 10000;
  font-family: 'Segoe UI', system-ui, -apple-system, BlinkMacSystemFont, sans-serif;
}

.teamsapp-mobile-top-bar__start {
  justify-self: start;
  min-width: 0;
}

.teamsapp-mobile-top-bar__center {
  justify-self: center;
  min-width: 0;
  max-width: min(520px, 56vw);
  text-align: center;
}

.teamsapp-mobile-top-bar__end {
  justify-self: end;
  min-width: 0;
  display: flex;
  align-items: center;
  justify-content: flex-end;
  gap: 8px;
}

.teamsapp-mobile-back-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 6px;
  min-height: var(--ts-nav-touch);
  padding: 0 14px 0 10px;
  border-radius: 999px;
  border: 1px solid var(--ts-nav-btn-border);
  background: var(--ts-nav-btn-bg);
  color: var(--ts-nav-text);
  text-decoration: none;
  font-size: 14px;
  font-weight: 600;
  letter-spacing: 0.01em;
  line-height: 1;
  white-space: nowrap;
  transition: background 0.18s ease, border-color 0.18s ease, transform 0.18s ease;
  -webkit-tap-highlight-color: transparent;
}

.teamsapp-mobile-back-btn:hover,
.teamsapp-mobile-back-btn:focus-visible {
  background: var(--ts-nav-btn-hover);
  border-color: rgba(255, 68, 68, 0.45);
  color: #fff;
  outline: none;
}

.teamsapp-mobile-back-btn:active {
  transform: scale(0.98);
}

.teamsapp-mobile-back-btn--placeholder {
  visibility: hidden;
  pointer-events: none;
}

.teamsapp-mobile-back-icon {
  width: 18px;
  height: 18px;
  flex-shrink: 0;
  stroke: currentColor;
  fill: none;
  stroke-width: 2;
  stroke-linecap: round;
  stroke-linejoin: round;
}

.teamsapp-mobile-back-text {
  display: inline-block;
}

.teamsapp-mobile-top-title {
  margin: 0;
  font-size: 15px;
  font-weight: 700;
  letter-spacing: 0.01em;
  color: var(--ts-nav-text);
  line-height: 1.25;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.teamsapp-mobile-top-extra select,
.teamsapp-mobile-top-extra .teamsapp-nav-select {
  min-height: var(--ts-nav-touch);
  padding: 0 36px 0 12px;
  border-radius: 12px;
  border: 1px solid var(--ts-nav-btn-border);
  background: rgba(255, 255, 255, 0.96);
  color: #111;
  font-size: 14px;
  font-weight: 600;
  max-width: min(220px, 42vw);
}

@media (min-width: 769px) {
  .teamsapp-mobile-top-bar {
    --ts-nav-height: 60px;
    padding-left: max(24px, env(safe-area-inset-left, 0px));
    padding-right: max(24px, env(safe-area-inset-right, 0px));
  }

  .teamsapp-mobile-top-bar__center {
    max-width: min(640px, 50vw);
  }

  .teamsapp-mobile-top-title {
    font-size: 16px;
  }

  .teamsapp-mobile-back-btn {
    padding: 0 16px 0 12px;
    font-size: 14px;
  }
}

@media (max-width: 480px) {
  .teamsapp-mobile-top-bar {
    column-gap: 8px;
    padding-left: max(12px, env(safe-area-inset-left, 0px));
    padding-right: max(12px, env(safe-area-inset-right, 0px));
  }

  .teamsapp-mobile-top-bar__center {
    max-width: 46vw;
  }

  .teamsapp-mobile-back-text--long {
    display: none;
  }

  .teamsapp-mobile-back-btn {
    padding: 0 12px 0 8px;
  }

  .teamsapp-mobile-top-extra select,
  .teamsapp-mobile-top-extra .teamsapp-nav-select {
    max-width: 100%;
    width: 100%;
    font-size: 16px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .teamsapp-mobile-back-btn {
    transition: none;
  }

  .teamsapp-mobile-back-btn:active {
    transform: none;
  }
}

/* Floating red back button — fixed top-left, follows scroll */
.teamsapp-floating-back {
  position: fixed;
  top: max(12px, env(safe-area-inset-top, 0px));
  left: max(12px, env(safe-area-inset-left, 0px));
  z-index: 10050;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 4px;
  min-height: 44px;
  padding: 0 16px 0 12px;
  border-radius: 999px;
  border: 1px solid rgba(255, 120, 120, 0.45);
  background: linear-gradient(135deg, #d40000 0%, #ff4444 100%);
  color: #fff;
  text-decoration: none;
  font-size: 14px;
  font-weight: 600;
  letter-spacing: 0.01em;
  line-height: 1;
  white-space: nowrap;
  box-shadow: 0 4px 18px rgba(212, 0, 0, 0.45), 0 2px 8px rgba(0, 0, 0, 0.35);
  -webkit-tap-highlight-color: transparent;
  transition: transform 0.18s ease, box-shadow 0.18s ease, filter 0.18s ease;
}

.teamsapp-floating-back:hover,
.teamsapp-floating-back:focus-visible {
  color: #fff;
  filter: brightness(1.06);
  box-shadow: 0 6px 22px rgba(212, 0, 0, 0.55), 0 2px 10px rgba(0, 0, 0, 0.4);
  outline: none;
}

.teamsapp-floating-back:active {
  transform: scale(0.97);
}

.teamsapp-floating-back .teamsapp-mobile-back-icon {
  stroke: #fff;
}

.teamsapp-floating-back-text {
  display: inline-block;
}

body.teamsapp-has-floating-back {
  padding-top: max(68px, calc(env(safe-area-inset-top, 0px) + 56px));
}

@media (max-width: 480px) {
  .teamsapp-floating-back {
    padding: 0 14px 0 10px;
    font-size: 13px;
  }

  .teamsapp-floating-back-text {
    display: none;
  }

  .teamsapp-floating-back {
    width: 44px;
    padding: 0;
  }
}

@media (prefers-reduced-motion: reduce) {
  .teamsapp-floating-back {
    transition: none;
  }

  .teamsapp-floating-back:active {
    transform: none;
  }
}

/* Chat pages using the shared bar */
body.teamsapp-has-nav-bar .chat-container {
  height: calc(100vh - var(--ts-nav-height, 56px) - env(safe-area-inset-top, 0px) - env(safe-area-inset-bottom, 0px));
  height: calc(100dvh - var(--ts-nav-height, 56px) - env(safe-area-inset-top, 0px) - env(safe-area-inset-bottom, 0px));
}

@media (max-width: 768px) {
  body.teamsapp-has-nav-bar .chat-container {
    height: calc(100vh - 56px - env(safe-area-inset-top, 0px) - env(safe-area-inset-bottom, 0px));
    height: calc(100dvh - 56px - env(safe-area-inset-top, 0px) - env(safe-area-inset-bottom, 0px));
  }
}