/* Modal */
  .modal-overlay {
    position: fixed;
    inset: 0;
    background: rgba(0, 0, 0, 0.7);
    backdrop-filter: blur(8px);
    display: none;
    align-items: center;
    justify-content: center;
    z-index: 100;
    padding: 20px;
  }
  .modal-overlay.active {
    display: flex;
    animation: fadeIn 0.2s ease;
  }
  @keyframes fadeIn { from { opacity: 0; } to { opacity: 1; } }
  .modal {
    background: var(--bg-elev);
    border: 1px solid var(--border-strong);
    border-radius: var(--radius-lg);
    width: 100%;
    max-width: 780px;
    max-height: 90vh;
    display: flex;
    flex-direction: column;
    overflow: hidden;
    animation: slideUp 0.3s ease;
  }
  @keyframes slideUp {
    from { transform: translateY(20px); opacity: 0; }
    to { transform: translateY(0); opacity: 1; }
  }
  .modal-header {
    padding: 20px 24px 16px;
    border-bottom: 1px solid var(--border);
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    gap: 16px;
  }
  .modal-title-block { flex: 1; }
  .modal-eyebrow {
    font-family: var(--font-mono);
    font-size: 11px;
    color: var(--accent);
    letter-spacing: 0.06em;
    margin-bottom: 6px;
  }
  .modal-title {
    font-family: var(--font-display);
    font-size: 17px;
    font-weight: 500;
    color: var(--text-primary);
    line-height: 1.4;
    letter-spacing: -0.01em;
  }
  .modal-close {
    background: transparent;
    border: none;
    color: var(--text-muted);
    font-size: 24px;
    cursor: pointer;
    padding: 0;
    line-height: 1;
    width: 28px;
    height: 28px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 4px;
    flex-shrink: 0;
  }
  .modal-close:hover { color: var(--text-primary); background: var(--bg-input); }
  .modal-body {
    padding: 20px 24px;
    overflow-y: auto;
    flex: 1;
  }
  .modal-footer {
    padding: 14px 24px;
    border-top: 1px solid var(--border);
    display: flex;
    gap: 8px;
    justify-content: flex-end;
    flex-wrap: wrap;
  }

  /* Lesson content */
  .lesson-content {
    font-size: 14px;
    line-height: 1.7;
    color: var(--text-primary);
  }
  .lesson-content h1, .lesson-content h2, .lesson-content h3 {
    color: var(--text-primary);
    margin: 18px 0 10px;
    font-weight: 600;
  }
  .lesson-content h1 { font-size: 18px; }
  .lesson-content h2 { font-size: 16px; color: var(--accent); }
  .lesson-content h3 { font-size: 14px; color: var(--warning); }
  .lesson-content p { margin: 10px 0; }
  .lesson-content ul, .lesson-content ol { margin: 10px 0; padding-left: 24px; }
  .lesson-content li { margin: 4px 0; }
  .lesson-content code {
    font-family: var(--font-mono);
    font-size: 13px;
    background: var(--bg-input);
    padding: 2px 6px;
    border-radius: 4px;
    color: var(--accent);
  }
  .lesson-content pre {
    background: var(--bg-input);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 14px 16px;
    overflow-x: auto;
    margin: 14px 0;
  }
  .lesson-content pre code {
    background: transparent;
    padding: 0;
    color: var(--text-primary);
    font-size: 13px;
    line-height: 1.7;
  }
  .lesson-content strong { color: var(--text-primary); font-weight: 600; }
  .lesson-content blockquote {
    border-left: 3px solid var(--accent);
    padding-left: 12px;
    color: var(--text-secondary);
    margin: 12px 0;
  }
  .lesson-content hr { border: none; border-top: 1px solid var(--border); margin: 20px 0; }

  /* Question area */
  .qa-toggle {
    background: var(--purple);
    color: var(--bg);
    border: none;
    padding: 8px 14px;
    border-radius: var(--radius);
    font-size: 12px;
    font-family: var(--font-mono);
    font-weight: 500;
    cursor: pointer;
  }
  .qa-toggle:hover { background: #d0bfe8; }
  .qa-block {
    background: rgba(184, 163, 217, 0.08);
    border-left: 3px solid var(--purple);
    border-radius: var(--radius);
    padding: 14px 16px;
    margin-top: 16px;
    display: none;
  }
  .qa-block.active { display: block; }
  .qa-label {
    font-family: var(--font-mono);
    font-size: 10px;
    color: var(--purple);
    letter-spacing: 0.06em;
    margin-bottom: 8px;
    font-weight: 600;
  }
  .qa-input {
    width: 100%;
    background: var(--bg-input);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 10px 12px;
    color: var(--text-primary);
    font-family: inherit;
    font-size: 13px;
    resize: vertical;
    min-height: 60px;
  }
  .qa-input:focus { outline: none; border-color: var(--purple); }
  .qa-history { margin-top: 12px; display: flex; flex-direction: column; gap: 12px; }
  .qa-msg {
    background: var(--bg-input);
    padding: 10px 12px;
    border-radius: var(--radius);
    font-size: 13px;
    line-height: 1.6;
  }
  .qa-msg-user { border-left: 2px solid var(--text-muted); }
  .qa-msg-user-label {
    font-family: var(--font-mono);
    font-size: 10px;
    color: var(--text-muted);
    margin-bottom: 4px;
  }
  .qa-msg-ai { border-left: 2px solid var(--purple); }
  .qa-msg-ai-label {
    font-family: var(--font-mono);
    font-size: 10px;
    color: var(--purple);
    margin-bottom: 4px;
  }

  /* Buttons */
  .btn {
    padding: 9px 16px;
    border-radius: var(--radius);
    font-size: 13px;
    font-family: inherit;
    font-weight: 500;
    cursor: pointer;
    border: none;
    transition: all 0.15s;
    display: inline-flex;
    align-items: center;
    gap: 6px;
  }
  .btn:disabled { opacity: 0.5; cursor: not-allowed; }
  .btn-primary { background: var(--accent); color: var(--bg); }
  .btn-primary:hover:not(:disabled) { background: var(--accent-hover); }
  .btn-success { background: var(--success); color: var(--bg); }
  .btn-success:hover:not(:disabled) { background: #6ee7b7; }
  .btn-secondary { background: var(--bg-input); color: var(--text-primary); border: 1px solid var(--border-strong); }
  .btn-secondary:hover:not(:disabled) { background: var(--bg-hover); }

  /* Loading */
  .loading {
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 40px 20px;
    color: var(--text-secondary);
    font-size: 13px;
  }
  .spinner {
    width: 20px;
    height: 20px;
    border: 2px solid var(--border);
    border-top-color: var(--accent);
    border-radius: 50%;
    animation: spin 0.8s linear infinite;
    margin-right: 12px;
  }
  @keyframes spin { to { transform: rotate(360deg); } }
  .error-box {
    background: var(--danger-bg);
    border: 1px solid rgba(217, 163, 163, 0.3);
    color: var(--danger);
    padding: 12px 14px;
    border-radius: var(--radius);
    font-size: 13px;
    margin: 12px 0;
  }

  /* Split lesson layout with notes */
  .lesson-split {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 20px;
  }
  .lesson-left, .lesson-right {
    display: flex;
    flex-direction: column;
    gap: 12px;
  }
  .notes-section {
    background: var(--bg-input);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 12px 14px;
  }
  .notes-title {
    font-size: 11px;
    font-weight: 600;
    color: var(--accent);
    margin-bottom: 10px;
    font-family: var(--font-mono);
    letter-spacing: 0.06em;
    display: flex;
    justify-content: space-between;
    align-items: center;
  }
  .notes-hint {
    font-size: 10px;
    color: var(--text-muted);
    font-weight: 400;
    letter-spacing: 0;
  }
  .notes-area {
    width: 100%;
    min-height: 90px;
    background: var(--bg);
    border: 1px solid var(--border);
    border-radius: 6px;
    padding: 8px 10px;
    color: var(--text-primary);
    font-family: inherit;
    font-size: 13px;
    line-height: 1.6;
    resize: none;
    overflow-y: hidden;
    box-sizing: border-box;
  }
  .notes-area:focus {
    outline: none;
    border-color: var(--accent);
    box-shadow: 0 0 0 2px var(--accent-glow);
  }
  .notes-area.recall {
    min-height: 120px;
    background: rgba(184, 163, 217, 0.05);
  }
  .notes-area.code-answer {
    font-family: var(--font-mono);
    font-size: 12px;
    background: #0d0d0d;
    tab-size: 2;
    -moz-tab-size: 2;
    line-height: 1.55;
  }
  .notes-sub-title {
    font-family: var(--font-mono);
    font-size: 10px;
    color: var(--text-secondary);
    margin: 10px 0 6px;
    letter-spacing: 0.06em;
    text-transform: uppercase;
    display: flex;
    align-items: center;
    gap: 6px;
  }
  .notes-sub-title span.dot {
    width: 4px;
    height: 4px;
    border-radius: 50%;
    background: var(--accent);
    display: inline-block;
  }
  .vocab-list {
    display: flex;
    flex-direction: column;
    gap: 4px;
  }
  .vocab-row {
    display: grid;
    grid-template-columns: minmax(0, 1fr) minmax(0, 1.4fr) auto auto;
    gap: 4px;
    align-items: center;
  }
  .vocab-input {
    background: var(--bg);
    border: 1px solid var(--border);
    border-radius: 4px;
    padding: 6px 8px;
    color: var(--text-primary);
    font-size: 12px;
    font-family: inherit;
    min-width: 0;
    box-sizing: border-box;
    width: 100%;
  }
  .vocab-input:focus {
    outline: none;
    border-color: var(--accent);
  }
  .vocab-btn {
    background: transparent;
    border: 1px solid var(--border);
    color: var(--text-secondary);
    width: 26px;
    height: 26px;
    border-radius: 4px;
    cursor: pointer;
    font-size: 11px;
    padding: 0;
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
  }
  .vocab-btn:hover { background: var(--bg-hover); color: var(--text-primary); border-color: var(--border-strong); }
  .vocab-btn.lookup:hover { color: var(--accent); border-color: var(--accent); }
  .vocab-btn.delete:hover { color: var(--danger); border-color: var(--danger); }
  .vocab-add {
    background: transparent;
    border: 1px dashed var(--border-strong);
    color: var(--text-secondary);
    padding: 6px 10px;
    border-radius: 4px;
    cursor: pointer;
    font-size: 12px;
    font-family: inherit;
    margin-top: 8px;
    width: 100%;
  }
  .vocab-add:hover { color: var(--accent); border-color: var(--accent); }
  .modal.lesson-modal { max-width: 1100px; }
  @media (max-width: 900px) {
    .lesson-split { grid-template-columns: 1fr; }
    .modal.lesson-modal { max-width: 780px; }
  }

  /* Fullscreen study view */
  .modal-overlay.study-view {
    padding: 0;
    background: var(--bg);
    backdrop-filter: none;
  }
  .modal-overlay.study-view .modal.lesson-modal {
    max-width: 100vw;
    max-height: 100vh;
    width: 100vw;
    height: 100vh;
    border-radius: 0;
    border: none;
    animation: fadeIn 0.25s ease;
  }
  .modal-overlay.study-view .modal-header {
    padding: 18px 3vw;
    background: var(--bg-elev);
    border-bottom: 1px solid var(--border);
    position: sticky;
    top: 0;
    z-index: 5;
  }
  .modal-overlay.study-view .modal-header-inner {
    width: 100%;
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    gap: 16px;
  }
  .modal-overlay.study-view .modal-title-block { flex: 1; }
  .modal-overlay.study-view .modal-title { font-size: 20px; }
  .modal-overlay.study-view .modal-body {
    padding: 28px 3vw;
    width: 100%;
    box-sizing: border-box;
  }
  .modal-overlay.study-view .modal-footer {
    padding: 16px 3vw;
    background: var(--bg-elev);
    border-top: 1px solid var(--border);
  }
  .modal-overlay.study-view .modal-footer-inner {
    width: 100%;
    display: flex;
    justify-content: flex-end;
    gap: 8px;
    flex-wrap: wrap;
  }
  .modal-overlay.study-view .lesson-split {
    grid-template-columns: minmax(0, 5fr) minmax(0, 6fr);
    gap: 28px;
  }
  .modal-overlay.study-view .notes-area { min-height: 130px; }
  .modal-overlay.study-view .notes-area.recall { min-height: 180px; }
  .modal-overlay.study-view .vocab-list { max-height: none; }
  .modal-overlay.study-view .lesson-left pre { max-height: 320px; }
  .study-exit-hint {
    font-family: var(--font-mono);
    font-size: 10px;
    color: var(--text-muted);
    letter-spacing: 0.06em;
  }
  @media (max-width: 900px) {
    .modal-overlay.study-view .lesson-split { grid-template-columns: 1fr; }
    .modal-overlay.study-view .modal-header { padding: 14px 20px; }
    .modal-overlay.study-view .modal-body { padding: 20px; }
    .modal-overlay.study-view .modal-footer { padding: 14px 20px; }
  }

  /* Reset button */
  .footer-bar {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-top: 24px;
    padding: 0 4px;
  }
  .footer-hint { font-size: 12px; color: var(--text-muted); }
  .btn-ghost {
    background: transparent;
    color: var(--text-secondary);
    border: 1px solid var(--border);
    padding: 6px 12px;
    border-radius: var(--radius);
    cursor: pointer;
    font-size: 12px;
  }
  .btn-ghost:hover { background: var(--bg-elev); color: var(--text-primary); }

  /* Responsive */
  @media (max-width: 640px) {
    body { padding: 16px 12px 48px; }
    .progress-summary { grid-template-columns: 1fr; }
    .progress-cell { border-left: none; border-top: 1px solid var(--border); padding: 12px 0 0; padding-left: 0; }
    .progress-cell:first-child { border-top: none; padding-top: 0; }
    .today-card { padding: 20px; }
    .today-title { font-size: 20px; }
    .week-grid { grid-template-columns: repeat(4, 1fr); }
    .week-grid .week-day:nth-child(n+8) { display: none; }
    .next-langs { grid-template-columns: 1fr; }
    .modal-header, .modal-body, .modal-footer { padding-left: 16px; padding-right: 16px; }
  }