/* ==========================================================================
   Skill Tree
   Visual learning path on the home page
   ========================================================================== */

.skill-tree {
  display: flex;
  flex-direction: column;
  align-items: center;
  padding: 24px 0;
  gap: 0;
}

.skill-tree-node {
  display: flex;
  flex-direction: column;
  align-items: center;
  position: relative;
  cursor: pointer;
  transition: transform 0.2s ease;
}

.skill-tree-node:hover { transform: scale(1.04); }

.skill-tree-connector {
  width: 3px;
  height: 32px;
  background: var(--border-color, rgba(255,255,255,0.15));
  transition: background-color 0.3s ease;
}

.skill-tree-connector.completed {
  background: var(--success, #4ecdc4);
}

.skill-tree-circle {
  width: 80px;
  height: 80px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 28px;
  border: 3px solid var(--border-color, rgba(255,255,255,0.2));
  background: var(--bg-card, #22223b);
  transition: border-color 0.3s ease, box-shadow 0.3s ease, background-color 0.3s ease;
  position: relative;
}

.skill-tree-node.completed .skill-tree-circle {
  border-color: var(--success, #4ecdc4);
  background: rgba(78, 205, 196, 0.1);
}

.skill-tree-node.current .skill-tree-circle {
  border-color: var(--accent, #61dafb);
  box-shadow: 0 0 0 4px rgba(97, 218, 251, 0.2), 0 0 16px rgba(97, 218, 251, 0.15);
  animation: current-glow 2s ease-in-out infinite;
}

.skill-tree-node.locked .skill-tree-circle {
  border-color: var(--border-color, rgba(255,255,255,0.1));
  background: var(--bg-tertiary, #2d3748);
  opacity: 0.5;
}

@keyframes current-glow {
  0%, 100% { box-shadow: 0 0 0 4px rgba(97, 218, 251, 0.2), 0 0 16px rgba(97, 218, 251, 0.15); }
  50%      { box-shadow: 0 0 0 6px rgba(97, 218, 251, 0.3), 0 0 24px rgba(97, 218, 251, 0.2); }
}

.skill-tree-label {
  margin-top: 6px;
  font-size: 13px;
  font-weight: 600;
  color: var(--text-primary, #e0e0e0);
  text-align: center;
  max-width: 120px;
}

.skill-tree-node.locked .skill-tree-label {
  color: var(--text-muted, #718096);
  opacity: 0.5;
}

.skill-tree-progress {
  font-size: 11px;
  color: var(--text-muted, #718096);
  margin-top: 2px;
}

.skill-tree-stars {
  margin-top: 4px;
  font-size: 14px;
  letter-spacing: 2px;
}

/* ── Phase Lessons Dropdown ── */
.skill-tree-lessons {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.3s ease;
  width: 280px;
  margin-top: 4px;
}

.skill-tree-lessons.open {
  max-height: 400px;
}

.skill-tree-lesson-item {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 8px 16px;
  font-size: 13px;
  color: var(--text-primary, #e0e0e0);
  text-decoration: none;
  border-radius: 6px;
  transition: background-color 0.2s ease;
}

.skill-tree-lesson-item:hover {
  background: var(--bg-hover, rgba(255,255,255,0.06));
}

.skill-tree-lesson-item .lesson-status {
  font-size: 14px;
  flex-shrink: 0;
}

.skill-tree-lesson-item.completed-lesson .lesson-status { color: var(--success, #4ecdc4); }
.skill-tree-lesson-item.locked-lesson { opacity: 0.4; pointer-events: none; }

/* ── Dashboard Stats (Home page) ── */
.dashboard-stats {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(140px, 1fr));
  gap: 12px;
  margin: 20px 0;
}

.dashboard-stat {
  padding: 16px;
  border-radius: 12px;
  background: var(--bg-card, #22223b);
  border: 1px solid var(--border-color, rgba(255,255,255,0.1));
  text-align: center;
}

.dashboard-stat .stat-icon { font-size: 24px; margin-bottom: 6px; }
.dashboard-stat .stat-value { font-size: 24px; font-weight: 700; color: var(--text-primary, #e0e0e0); }
.dashboard-stat .stat-label { font-size: 12px; color: var(--text-muted, #718096); margin-top: 2px; }

/* ── Responsive ── */
@media (max-width: 768px) {
  .skill-tree-circle { width: 64px; height: 64px; font-size: 22px; }
  .skill-tree-label { font-size: 12px; max-width: 100px; }
  .skill-tree-lessons { width: 240px; }
  .dashboard-stats { grid-template-columns: repeat(2, 1fr); }
}