/* Day jump button in analysis content */
  .day-jump-btn {
    display: inline-flex;
    align-items: center;
    gap: 3px;
    background: var(--accent-glow);
    color: var(--accent);
    border: 1px solid rgba(225, 225, 225, 0.2);
    padding: 1px 8px;
    border-radius: 4px;
    font-family: var(--font-mono);
    font-size: 11px;
    font-weight: 500;
    cursor: pointer;
    margin: 0 1px;
    vertical-align: baseline;
    transition: all 0.15s;
    line-height: 1.5;
  }
  .day-jump-btn:hover {
    background: rgba(225, 225, 225, 0.15);
    border-color: var(--accent);
    color: var(--text-primary);
    transform: translateY(-1px);
  }
  .day-jump-btn:active {
    transform: translateY(0);
  }
  /* Saved lesson content preview */
  .saved-lesson-preview {
    background: var(--bg-input);
    border: 1px solid var(--border);
    border-left: 3px solid var(--accent);
    border-radius: var(--radius);
    padding: 14px 16px;
    max-height: 500px;
    overflow-y: auto;
    font-size: 13px;
    line-height: 1.6;
    color: var(--text-primary);
  }
  .saved-lesson-preview h1, .saved-lesson-preview h2, .saved-lesson-preview h3 {
    color: var(--text-primary);
    margin: 12px 0 8px;
    font-weight: 600;
  }
  .saved-lesson-preview h1 { font-size: 16px; }
  .saved-lesson-preview h2 { font-size: 15px; color: var(--accent); }
  .saved-lesson-preview h3 { font-size: 13px; color: var(--warning); }
  .saved-lesson-preview code {
    font-family: var(--font-mono);
    font-size: 12px;
    background: var(--bg);
    padding: 1px 5px;
    border-radius: 3px;
    color: var(--accent);
  }
  .saved-lesson-preview pre {
    background: var(--bg);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 10px 12px;
    overflow-x: auto;
    margin: 10px 0;
  }
  .saved-lesson-preview pre code {
    background: transparent;
    padding: 0;
    color: var(--text-primary);
  }
  .saved-lesson-preview ul, .saved-lesson-preview ol {
    margin: 8px 0;
    padding-left: 22px;
  }
  .saved-lesson-preview p { margin: 8px 0; }
  .btn-mini {
    background: transparent;
    border: 1px solid var(--border);
    color: var(--text-secondary);
    padding: 3px 10px;
    border-radius: 4px;
    font-family: var(--font-mono);
    font-size: 10px;
    cursor: pointer;
    letter-spacing: 0.02em;
    transition: all 0.15s;
  }
  .btn-mini:hover { border-color: var(--accent); color: var(--accent); }
  .saved-lesson-status {
    font-size: 10px;
    color: var(--text-muted);
    font-weight: 400;
    letter-spacing: 0;
    display: flex;
    align-items: center;
    gap: 8px;
  }
  .saved-lesson-status.saved { color: var(--success); }

  /* Generate lesson button */
  .btn-generate-lesson {
    display: block;
    width: 100%;
    padding: 18px 24px;
    background: var(--accent);
    color: var(--bg);
    border: none;
    border-radius: var(--radius);
    font-size: 15px;
    font-weight: 500;
    font-family: var(--font-display);
    cursor: pointer;
    transition: all 0.15s;
    letter-spacing: -0.01em;
    margin-bottom: 8px;
  }
  .btn-generate-lesson:hover {
    background: var(--accent-hover);
    transform: translateY(-1px);
  }
  .btn-generate-lesson:disabled {
    opacity: 0.5;
    cursor: not-allowed;
    transform: none;
  }
  .btn-regen {
    background: transparent;
    border: 1px solid var(--border);
    color: var(--text-secondary);
    padding: 4px 12px;
    border-radius: 4px;
    font-family: var(--font-mono);
    font-size: 11px;
    cursor: pointer;
    transition: all 0.15s;
  }
  .btn-regen:hover { color: var(--warning); border-color: var(--warning); }
  .lesson-generating {
    text-align: center;
    padding: 50px 20px;
    background: var(--bg-input);
    border-radius: var(--radius);
    border: 1px solid var(--border);
  }
  .advanced-options {
    margin-top: 16px;
    border-top: 1px solid var(--border);
    padding-top: 12px;
  }
  .advanced-options summary {
    cursor: pointer;
    font-size: 11px;
    color: var(--text-muted);
    font-family: var(--font-mono);
    letter-spacing: 0.04em;
    padding: 6px 0;
    user-select: none;
  }
  .advanced-options summary:hover { color: var(--text-secondary); }
  .advanced-options[open] summary { color: var(--text-secondary); margin-bottom: 8px; }

  /* Challenge tabs */
  .challenge-tabs {
    display: flex;
    gap: 2px;
    margin-bottom: 14px;
    border-bottom: 1px solid var(--border);
  }
  .challenge-tab {
    background: transparent;
    border: none;
    color: var(--text-secondary);
    padding: 8px 14px;
    border-bottom: 2px solid transparent;
    cursor: pointer;
    font-family: var(--font-mono);
    font-size: 11px;
    transition: all 0.15s;
    letter-spacing: 0.04em;
    display: inline-flex;
    align-items: center;
    gap: 8px;
  }
  .challenge-tab:hover { color: var(--text-primary); }
  .challenge-tab.active {
    color: var(--accent);
    border-bottom-color: var(--accent);
  }
  .challenge-tab-dot {
    width: 6px;
    height: 6px;
    border-radius: 50%;
    background: var(--border-strong);
    flex-shrink: 0;
  }
  .challenge-tab-dot.has-code { background: var(--warning); }
  .challenge-tab-dot.graded { background: var(--success); }
  .challenge-panel { display: none; }
  .challenge-panel.active { display: block; }
  .btn-grade {
    background: var(--accent);
    color: var(--bg);
    border: none;
    padding: 10px 22px;
    border-radius: var(--radius);
    font-family: var(--font-display);
    font-size: 13px;
    font-weight: 500;
    cursor: pointer;
    transition: all 0.15s;
    letter-spacing: -0.01em;
  }
  .btn-grade:hover:not(:disabled) {
    background: var(--accent-hover);
    transform: translateY(-1px);
  }
  .btn-grade:disabled {
    opacity: 0.5;
    cursor: not-allowed;
    transform: none;
  }
  .challenge-feedback {
    margin-top: 14px;
    padding: 14px 16px;
    background: var(--bg-input);
    border-left: 3px solid var(--success);
    border-radius: var(--radius);
    font-size: 12px;
    line-height: 1.65;
    display: none;
  }
  .challenge-feedback.has-content { display: block; }
  .challenge-feedback.grading { border-left-color: var(--warning); }
  .challenge-feedback.error { border-left-color: var(--danger); color: var(--danger); }
  .challenge-feedback h3 {
    font-size: 13px;
    color: var(--accent);
    margin: 10px 0 6px;
    font-weight: 600;
  }
  .challenge-feedback h3:first-child { margin-top: 0; }
  .challenge-feedback code {
    font-family: var(--font-mono);
    font-size: 11px;
    background: var(--bg);
    padding: 1px 5px;
    border-radius: 3px;
  }
  .challenge-feedback pre {
    background: var(--bg);
    border: 1px solid var(--border);
    border-radius: 4px;
    padding: 8px 10px;
    overflow-x: auto;
    margin: 8px 0;
  }
  .challenge-feedback pre code { background: transparent; padding: 0; }
  .challenge-feedback ul, .challenge-feedback ol { margin: 6px 0; padding-left: 20px; }
  .challenge-feedback p { margin: 6px 0; }