.hamburger-btn {
  display: none;
  width: 40px;
  height: 40px;
  border: none;
  background: none;
  color: var(--text-secondary);
  cursor: pointer;
  font-size: 22px;
  padding: 0;
  line-height: 1;
}

.term-scroll-controls {
  display: none;
}

.mobile-menu-btn {
  display: none;
}

.mobile-phase-badge {
  display: none !important;
}

.mobile-menu-dropdown {
  display: contents;
}

@media (max-width: 768px) {

  .hamburger-btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
  }

  .sidebar {
    transform: translateX(-100%);
    transition: transform 0.25s ease;
    z-index: 200;
    width: 52px;
    background: var(--bg-surface);
  }

  .sidebar.open {
    transform: translateX(0);
  }

  .sidebar-overlay {
    display: none;
    position: fixed;
    inset: 0;
    background: rgba(0, 0, 0, 0.4);
    z-index: 199;
  }

  .sidebar-overlay.visible {
    display: block;
  }

  .header {
    padding: 0 12px;
    height: 48px;
    gap: 8px;
  }

  .header-left {
    gap: 8px;
  }

  .header-title {
    display: none;
  }

  .header-branch {
    display: none;
  }

  .header-right {
    gap: 6px;
    flex-wrap: nowrap;
    overflow: visible;
    align-items: center;
  }

  .mobile-phase-badge {
    display: inline-flex !important;
  }

  .mobile-menu-btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 36px;
    height: 36px;
    border: 1px solid var(--border);
    border-radius: var(--radius-sm);
    background: none;
    color: var(--text-primary);
    font-size: 20px;
    cursor: pointer;
  }

  .mobile-menu-dropdown {
    display: none !important;
    position: fixed !important;
    top: 48px !important;
    right: 8px !important;
    left: auto !important;
    width: 240px !important;
    height: auto !important;
    z-index: 9999 !important;
    background: #1e2130 !important;
    border: 1px solid #2a2e42 !important;
    border-radius: 6px !important;
    padding: 10px !important;
    flex-direction: column !important;
    gap: 8px !important;
    box-shadow: 0 8px 24px rgba(0, 0, 0, 0.7) !important;
  }

  [data-theme="light"] .mobile-menu-dropdown {
    background: #ffffff !important;
    border-color: #e0dbd0 !important;
  }

  .mobile-menu-dropdown.open {
    display: flex !important;
  }

  .mobile-menu-dropdown > * {
    position: relative;
    z-index: 1;
  }

  .mobile-menu-dropdown #sessionBlock {
    display: flex !important;
    flex-direction: column;
    gap: 6px;
    width: 100%;
  }

  .mobile-menu-dropdown #sessionBlock .btn-dropdown {
    display: block;
    position: relative;
    width: 100%;
  }

  .mobile-menu-dropdown .btn-dropdown-menu {
    position: absolute;
    top: 100%;
    right: 0;
    left: 0;
    min-width: 100%;
    z-index: 500;
  }

  .mobile-menu-dropdown .btn {
    width: 100%;
    justify-content: center;
    padding: 8px 12px;
    font-size: 0.78rem;
  }

  .mobile-menu-dropdown .header-refresh-btn {
    display: none;
  }

  .mobile-menu-dropdown .theme-toggle {
    display: none;
  }

  .btn-dropdown-item[onclick*="'split'"] {
    display: none;
  }

  .header-right .locale-select {
    display: none;
  }

  .mobile-menu-dropdown .locale-select {
    display: block !important;
    width: 100%;
  }

  .mobile-menu-dropdown #phaseLabel {
    display: none;
  }

  .header-right .btn {
    padding: 0 8px;
    font-size: 0.72rem;
    white-space: nowrap;
  }

  .tab-bar {
    margin-left: 0;
    padding: 0 12px;
    -webkit-overflow-scrolling: touch;
  }

  .tab-btn {
    padding: 10px 12px;
    font-size: 0.75rem;
  }

  .main {
    margin-left: 0;
    height: calc(100vh - 48px - 38px);
  }

  .split-main {
    padding: 12px;
  }

  #splitTerminalBtn {
    display: none;
  }

  .split-handle,
  .split-terminal {
    display: none !important;
  }

  .card-header {
    padding: 10px 12px;
    flex-wrap: wrap;
    gap: 6px;
  }

  .card-body {
    padding: 12px;
  }

  .card-title {
    font-size: 0.8rem;
  }

  #panel-plan .card-header .card-title,
  #panel-preplanning .card-header .card-title {
    position: static;
    left: auto;
    transform: none;
    pointer-events: auto;
  }

  #panel-plan .card-header,
  #panel-preplanning .card-header {
    flex-wrap: wrap;
  }

  #panel-plan .card-header > div,
  #panel-preplanning .card-header > div {
    flex-wrap: wrap;
    gap: 4px;
  }

  .btn {
    min-height: 36px;
    padding: 8px 14px;
  }

  .btn-sm {
    min-height: 32px;
    padding: 6px 10px;
  }

  .badge {
    font-size: 0.68rem;
    padding: 2px 8px;
  }

  .phase-labels {
    flex-wrap: wrap;
    gap: 2px 8px;
  }

  .phase-label {
    font-size: 0.55rem;
    min-width: 0;
    word-break: break-word;
    line-height: 1.2;
  }

  .phase-edit-btn {
    font-size: 0.9rem !important;
  }

  .phase-action-grid {
    grid-template-columns: 1fr;
  }

  .context-row {
    flex-direction: column;
    gap: 8px;
  }

  .context-field {
    width: 100%;
  }

  .qa-add-form {
    flex-direction: column;
    gap: 6px;
  }

  .qa-add-form .context-input {
    width: 100%;
  }

  .diff-controls {
    flex-wrap: wrap;
    gap: 6px;
    padding: 8px 12px;
  }

  .diff-controls input[type="text"] {
    max-width: 100% !important;
    flex: 1 1 100%;
  }

  .diff-layout {
    flex-direction: column;
    height: auto;
    min-height: 0;
  }

  .diff-file-list {
    width: 100%;
    max-width: 100%;
    border-right: none;
    border-bottom: 1px solid var(--border);
  }

  .diff-file-list > *:not(.diff-file-list-header) {
    display: none;
  }

  .diff-file-list.mobile-open {
    max-height: 240px;
    overflow: auto;
  }

  .diff-file-list.mobile-open > *:not(.diff-file-list-header) {
    display: block;
  }

  .diff-file-list-header {
    cursor: pointer;
  }

  .diff-file-list-header::after {
    content: ' ▸';
    font-size: 0.7rem;
  }

  .diff-file-list.mobile-open .diff-file-list-header::after {
    content: ' ▾';
  }

  .diff-resize-handle {
    display: none;
  }

  .diff-content {
    min-height: 300px;
  }

  .scope-item {
    padding: 8px 10px;
  }

  .scope-remove {
    opacity: 1;
  }

  .finding {
    padding: 8px 10px;
  }

  .finding-ref {
    font-size: 0.7rem;
  }

  .research-group-header {
    padding: 8px 10px;
  }

  .plan-description {
    padding: 10px 12px;
    font-size: 0.85rem;
  }

  .plan-task-header {
    padding: 6px 8px;
  }

  .plan-task-detail {
    padding: 4px 8px 8px 20px;
  }

  #planDiagram,
  #systemDiagram {
    overflow: auto;
    -webkit-overflow-scrolling: touch;
  }

  .diagram-zoom-controls {
    margin-left: 0;
  }

  .comment-thread {
    margin-left: 0;
    margin-right: 0;
  }

  .plan-task > .comment-thread {
    margin-left: 0;
    margin-right: 0;
  }

  .terminal-toolbar {
    flex-wrap: wrap;
    gap: 6px;
    padding: 6px 8px;
  }

  .terminal-session-list {
    order: 3;
    width: 100%;
    padding: 0;
  }

  .term-scroll-controls {
    display: flex;
    flex-direction: column;
    gap: 6px;
    position: fixed;
    bottom: 20px;
    right: 12px;
    z-index: 500;
  }

  .term-scroll-btn {
    width: 44px;
    height: 44px;
    border-radius: 50%;
    border: 1px solid var(--border);
    background: var(--bg-raised);
    color: var(--text-primary);
    font-size: 18px;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    opacity: 0.85;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.3);
  }

  .term-scroll-btn:active {
    opacity: 1;
    background: var(--accent-dim);
  }

  .file-preview-content {
    width: 98%;
    max-width: none;
    max-height: 90vh;
  }

  .selector-container {
    padding: 20px 16px;
  }

  .selector-title {
    font-size: 1.3rem;
  }

  .project-card {
    padding: 10px 12px;
    gap: 10px;
  }

  .project-card-actions {
    flex-direction: column;
    gap: 4px;
  }

  .pp-discussion-header {
    flex-direction: column;
    gap: 4px;
  }

  .pp-discussion-meta {
    align-self: flex-start;
  }

  .pp-gate-actions {
    flex-direction: column;
  }

  .pp-inline-comment-form {
    flex-direction: column;
    gap: 4px;
  }

  .review-thread-header {
    flex-wrap: wrap;
  }

  .review-reply-form {
    flex-direction: column;
  }

  .diagram-overlay-content {
    width: 98vw;
    height: 95vh;
    max-width: none;
    max-height: none;
    border-radius: 4px;
  }

  .context-label {
    font-size: 0.75rem;
  }

  .context-input {
    font-size: 0.85rem;
    padding: 10px 12px;
  }

  .context-textarea {
    font-size: 0.85rem;
    min-height: 120px;
  }

  #criteriaBody .criteria-add-form > div:first-child {
    flex-direction: column;
  }

  #criteriaBody .criteria-add-form select {
    flex: none;
    width: 100%;
  }
}

@media (max-width: 480px) {


  .header {
    padding: 0 8px;
  }

  .split-main {
    padding: 8px;
  }

  .card-header {
    padding: 8px 10px;
  }

  .card-body {
    padding: 8px 10px;
  }

  .diff-file-list {
    max-height: 150px;
  }

  .tab-btn {
    padding: 8px 8px;
    font-size: 0.7rem;
  }

  .toggle-group {
    flex-wrap: wrap;
  }

  .toggle-opt {
    font-size: 0.68rem;
    padding: 4px 8px;
  }
}