/* ==========================================================================
   Level 2 Course Units – page template styles
   Enqueue after level-2-getting-started.css
   ========================================================================== */

/* --------------------------------------------------------------------------
   Unit selector tab strip
   -------------------------------------------------------------------------- */
.cu-unit-tabs {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  margin-bottom: 20px;
}

.cu-unit-tab {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 52px;
  height: 52px;
  border-radius: 14px;
  background: var(--white);
  border: 2px solid var(--line);
  box-shadow: 0 4px 12px rgba(63, 68, 72, 0.07);
  text-decoration: none;
  transition: background 0.15s ease, border-color 0.15s ease,
              transform 0.12s ease, box-shadow 0.15s ease;
  cursor: pointer;
}

.cu-unit-tab:hover {
  background: var(--pd-grey-soft);
  border-color: var(--unit-color, var(--pd-blue));
  transform: translateY(-2px);
}

.cu-unit-tab--active {
  background: var(--unit-color, var(--pd-blue));
  border-color: var(--unit-color, var(--pd-blue));
  box-shadow: 0 6px 18px rgba(0, 0, 0, 0.18);
  transform: translateY(-2px);
}

.cu-unit-tab__num {
  font-size: 1.1rem;
  font-weight: 900;
  color: var(--pd-grey-dark);
  letter-spacing: -0.03em;
}

.cu-unit-tab--active .cu-unit-tab__num {
  color: var(--white);
}

/* --------------------------------------------------------------------------
   Unit panes
   -------------------------------------------------------------------------- */
.cu-unit-content {
  position: relative;
}

.cu-unit-pane {
  display: none;
}

.cu-unit-pane--active {
  display: block;
}

/* --------------------------------------------------------------------------
   Sub-tab nav (Overview / Learning session / Further reading)
   -------------------------------------------------------------------------- */
.cu-sub-tabs {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  margin-bottom: 22px;
  padding-bottom: 18px;
  border-bottom: 1px solid var(--line);
}

.cu-sub-tab {
  display: inline-flex;
  align-items: center;
  gap: 7px;
  padding: 10px 18px;
  border-radius: 10px;
  border: 2px solid var(--line);
  background: var(--white);
  color: var(--pd-grey-dark);
  font: 700 0.88rem/1 inherit;
  cursor: pointer;
  transition: background 0.15s ease, border-color 0.15s ease, color 0.15s ease;
}

.cu-sub-tab:hover {
  background: var(--pd-grey-soft);
  border-color: var(--pd-grey);
}

.cu-sub-tab--active {
  background: var(--pd-purple-soft);
  border-color: var(--pd-purple);
  color: var(--pd-purple);
}

/* --------------------------------------------------------------------------
   Sub panes
   -------------------------------------------------------------------------- */
.cu-sub-pane {
  display: none;
}

.cu-sub-pane--active {
  display: block;
}

/* --------------------------------------------------------------------------
   Objectives list
   -------------------------------------------------------------------------- */
.cu-objectives {
  list-style: none;
  margin: 14px 0 0;
  padding: 0;
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.cu-objectives li {
  display: flex;
  align-items: flex-start;
  gap: 12px;
  font-size: 1rem;
  color: var(--pd-grey-dark);
  line-height: 1.6;
  padding: 12px 16px;
  background: var(--pd-grey-soft);
  border-radius: 12px;
  border-left: 3px solid var(--pd-blue);
}

.cu-objectives li::before {
  content: '✓';
  font-weight: 900;
  color: var(--standard-green);
  flex-shrink: 0;
  font-size: 1rem;
  margin-top: 1px;
}

/* --------------------------------------------------------------------------
   Launch session row
   -------------------------------------------------------------------------- */
.cu-launch-row {
  display: grid;
  grid-template-columns: auto 1fr;
  gap: 28px;
  align-items: center;
  margin-top: 8px;
}

.cu-play-btn {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 10px;
  width: 140px;
  height: 140px;
  border-radius: 20px;
  background: var(--unit-color, var(--pd-purple));
  color: var(--white);
  border: none;
  cursor: pointer;
  font: 700 0.85rem/1.2 inherit;
  transition: transform 0.15s ease, box-shadow 0.15s ease, filter 0.15s ease;
  text-align: center;
  flex-shrink: 0;
}

.cu-play-btn .ti {
  font-size: 3rem;
}

.cu-play-btn:hover {
  transform: scale(1.05);
  box-shadow: 0 12px 32px rgba(0, 0, 0, 0.22);
  filter: brightness(1.08);
}

.cu-launch-tips {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.cu-launch-tips li {
  font-size: 0.95rem;
  color: var(--pd-grey-dark);
  line-height: 1.55;
  padding-left: 20px;
  position: relative;
}

.cu-launch-tips li::before {
  content: '›';
  position: absolute;
  left: 0;
  color: var(--pd-blue);
  font-weight: 900;
  font-size: 1.1rem;
}

/* --------------------------------------------------------------------------
   Further reading list
   -------------------------------------------------------------------------- */
.cu-reading-list {
  list-style: none;
  margin: 10px 0 0;
  padding: 0;
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.cu-reading-list li a {
  display: inline-flex;
  align-items: center;
  gap: 7px;
  padding: 12px 16px;
  background: var(--pd-blue-soft);
  border: 1px solid rgba(0, 168, 232, 0.2);
  border-radius: 12px;
  color: var(--pd-blue-dark);
  font-size: 0.9rem;
  font-weight: 600;
  text-decoration: none;
  transition: background 0.15s ease, border-color 0.15s ease;
  width: 100%;
}

.cu-reading-list li a:hover {
  background: var(--pd-blue);
  border-color: var(--pd-blue);
  color: var(--white);
}

.cu-reading-list li a .ti {
  flex-shrink: 0;
  opacity: 0.7;
}

/* --------------------------------------------------------------------------
   Responsive
   -------------------------------------------------------------------------- */
@media (max-width: 680px) {
  .cu-unit-tabs {
    gap: 4px;
  }

  .cu-unit-tab {
    width: 44px;
    height: 44px;
    border-radius: 10px;
  }

  .cu-unit-tab__num {
    font-size: 0.95rem;
  }

  .cu-launch-row {
    grid-template-columns: 1fr;
    justify-items: center;
  }

  .cu-play-btn {
    width: 120px;
    height: 120px;
  }

  .cu-sub-tabs {
    flex-direction: column;
  }

  .cu-sub-tab {
    justify-content: center;
  }
}