#tutorial-panel {
  width: 280px;
  min-width: 280px;
  height: 100%;
  overflow-y: auto;
  background: #1a1a1a;
  border-right: 1px solid #2d2d2d;
  box-sizing: border-box;
  padding-bottom: 20px;
}

#tutorial-panel::-webkit-scrollbar {
  width: 5px;
}

#tutorial-panel::-webkit-scrollbar-track {
  background: #1a1a1a;
}

#tutorial-panel::-webkit-scrollbar-thumb {
  background: #333;
  border-radius: 3px;
}

.tutorial-header {
  padding: 16px 16px 8px;
  border-bottom: 1px solid #2d2d2d;
}

.tutorial-title {
  font-size: 15px;
  font-weight: 600;
  color: #e0e0e0;
}

.phase-tabs {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 4px;
  padding: 10px 12px;
}

.phase-tab {
  background: #252525;
  color: #888;
  border: none;
  border-radius: 6px;
  padding: 7px 4px;
  cursor: pointer;
  font-size: 12px;
  transition: all 0.15s;
}

.phase-tab.active {
  background: #3a3a5c;
  color: #9090f0;
  font-weight: 600;
}

.phase-tab:hover {
  background: #333;
  color: #ccc;
}

.phase-content {
  padding: 0 14px 14px;
}

.phase-title {
  font-size: 14px;
  font-weight: 700;
  color: #e0e0e0;
  margin: 12px 0 4px;
}

.phase-goal {
  font-size: 12px;
  color: #5bb4f0;
  background: #1a2a3a;
  padding: 8px 10px;
  border-radius: 6px;
  margin-bottom: 10px;
  line-height: 1.5;
}

.section-label {
  font-size: 11px;
  color: #666;
  text-transform: uppercase;
  letter-spacing: 0.5px;
  margin: 12px 0 6px;
}

.steps-list {
  margin: 0;
  padding-left: 18px;
  color: #bbb;
  font-size: 13px;
  line-height: 1.8;
}

.steps-list li {
  margin-bottom: 2px;
}

.algorithm-card {
  background: #232323;
  border: 1px solid #2d2d2d;
  border-radius: 8px;
  padding: 11px 12px;
  margin-bottom: 8px;
}

.alg-name {
  font-size: 13px;
  font-weight: 600;
  color: #e0e0e0;
  margin-bottom: 5px;
}

.alg-notation {
  display: block;
  font-family: 'SF Mono', 'Consolas', monospace;
  font-size: 13px;
  color: #4fc3f7;
  background: #162030;
  padding: 6px 10px;
  border-radius: 5px;
  margin: 5px 0;
  letter-spacing: 0.5px;
  white-space: pre-wrap;
  word-break: break-all;
}

.alg-desc {
  font-size: 12px;
  color: #999;
  margin-top: 4px;
  line-height: 1.5;
}

.alg-tip {
  font-size: 11px;
  color: #666;
  margin-top: 4px;
  line-height: 1.4;
}

.highlight-btn {
  width: 100%;
  margin-top: 14px;
  padding: 9px;
  border: none;
  border-radius: 7px;
  background: #2a3a2a;
  color: #6abf6a;
  cursor: pointer;
  font-size: 13px;
  transition: all 0.15s;
}

.highlight-btn.active {
  background: #1e3a1e;
  color: #4caf50;
  border: 1px solid #4caf50;
}

.highlight-btn:hover {
  background: #334433;
}