*, *::before, *::after {
      box-sizing: border-box;
      margin: 0;
      padding: 0;
    }

    html, body {
      height: 100%;
      width: 100%;
      max-width: 100vw;
      overflow-x: hidden;
      background-color: var(--color-bg);
      color: var(--color-text-primary);
      font-family: var(--font-sans);
      font-size: var(--font-size-md);
      line-height: var(--line-height-normal);
      -webkit-font-smoothing: antialiased;
      -moz-osx-font-smoothing: grayscale;
      box-sizing: border-box;
    }


    .skip-link {
      position: absolute;
      top: -100px;
      left: 16px;
      background: var(--color-accent);
      color: var(--color-accent-text);
      padding: var(--space-2) var(--space-4);
      border-radius: var(--radius-sm);
      font-weight: var(--font-weight-medium);
      font-size: var(--font-size-sm);
      z-index: 10000;
      text-decoration: none;
      transition: top var(--motion-fast);
    }
    .skip-link:focus {
      top: 16px;
      outline: none;
      box-shadow: var(--focus-ring);
    }


    :focus-visible {
      outline: none;
      box-shadow: var(--focus-ring);
    }


    .icon {
      width: 16px;
      height: 16px;
      display: inline-block;
      vertical-align: middle;
      flex-shrink: 0;
      stroke-width: 2;
      stroke: currentColor;
      fill: none;
      stroke-linecap: round;
      stroke-linejoin: round;
    }


    .app-header {
      height: 52px;
      height: calc(52px + env(safe-area-inset-top, 0px));
      min-height: 52px;
      min-height: calc(52px + env(safe-area-inset-top, 0px));
      width: 100%;
      max-width: 100vw;
      box-sizing: border-box;
      background-color: var(--color-surface);
      border-bottom: 1px solid var(--color-border);
      display: flex;
      align-items: center;
      justify-content: space-between;
      padding: env(safe-area-inset-top, 0px) var(--space-4) 0;
      z-index: 40;
      flex-shrink: 0;
    }

    .header-left {
      display: flex;
      align-items: center;
      gap: var(--space-3);
    }

    .header-brand {
      display: inline-flex;
      align-items: center;
      gap: var(--space-2);
      text-decoration: none;
      color: var(--color-text-primary);
    }

    .messages-brand-logo {
      display: block;
      width: auto;
      height: 26px;
      max-width: 26px;
      aspect-ratio: 927 / 1152;
      object-fit: contain;
      flex: 0 0 auto;
    }

    .header-title {
      font-size: var(--font-size-lg);
      font-weight: var(--font-weight-semibold);
      color: var(--color-text-primary);
      letter-spacing: -0.01em;
    }

    .header-right {
      display: flex;
      align-items: center;
      gap: var(--space-2);
    }


    .header-user-badge {
      display: flex;
      align-items: center;
      gap: var(--space-2);
      padding: var(--space-1) var(--space-3);
      border-radius: var(--radius-sm);
      background-color: var(--color-surface-subtle);
      border: 1px solid var(--color-border);
      font-size: var(--font-size-sm);
      color: var(--color-text-secondary);
      max-width: min(280px, 42vw);
    }

    .header-user-avatar {
      width: 20px;
      height: 20px;
      border-radius: var(--radius-full);
      background-color: var(--color-border);
      overflow: hidden;
      display: flex;
      align-items: center;
      justify-content: center;
      font-size: 10px;
      font-weight: var(--font-weight-semibold);
      color: var(--color-text-secondary);
      flex-shrink: 0;
    }

    .header-user-name {
      font-weight: var(--font-weight-medium);
      color: var(--color-text-primary);
      white-space: nowrap;
      overflow: hidden;
      text-overflow: ellipsis;
    }

    .header-user-role {
      color: var(--color-text-muted);
      font-size: var(--font-size-xs);
      white-space: nowrap;
      overflow: hidden;
      text-overflow: ellipsis;
      max-width: 150px;
    }


    .btn-icon {
      width: 32px;
      height: 32px;
      border-radius: var(--radius-sm);
      border: 1px solid var(--color-border);
      background-color: var(--color-surface);
      color: var(--color-text-secondary);
      display: inline-flex;
      align-items: center;
      justify-content: center;
      cursor: pointer;
      transition: background-color var(--motion-fast), color var(--motion-fast), border-color var(--motion-fast);
      position: relative;
    }
    .btn-icon:hover {
      background-color: var(--color-surface-hover);
      color: var(--color-text-primary);
      border-color: var(--color-border-hover);
    }

    .btn-ghost-nav {
      display: inline-flex;
      align-items: center;
      gap: var(--space-2);
      padding: 6px var(--space-3);
      height: 32px;
      border-radius: var(--radius-sm);
      border: 1px solid var(--color-border);
      background-color: var(--color-surface);
      color: var(--color-text-primary);
      text-decoration: none;
      font-size: var(--font-size-sm);
      font-weight: var(--font-weight-medium);
      transition: background-color var(--motion-fast), border-color var(--motion-fast);
    }
    .btn-ghost-nav:hover {
      background-color: var(--color-surface-hover);
      border-color: var(--color-border-hover);
    }


    [data-tooltip] {
      position: relative;
    }
    [data-tooltip]::after {
      content: attr(data-tooltip);
      position: absolute;
      top: calc(100% + 6px);
      left: 50%;
      transform: translateX(-50%);
      background-color: var(--color-text-primary);
      color: var(--color-text-inverse);
      font-size: var(--font-size-xs);
      font-weight: var(--font-weight-regular);
      padding: 4px 8px;
      border-radius: var(--radius-xs);
      white-space: nowrap;
      pointer-events: none;
      opacity: 0;
      transition: opacity var(--motion-fast);
      box-shadow: var(--shadow-tooltip);
      z-index: 100;
    }
    [data-tooltip]:hover::after {
      opacity: 1;
    }


    .messages-layout {
      height: calc(100vh - 52px);
      height: calc(var(--messages-viewport-height, 100dvh) - 52px - env(safe-area-inset-top, 0px));
      width: 100%;
      max-width: 100vw;
      display: flex;
      overflow: hidden;
      background-color: var(--color-bg);
      position: relative;
    }


    .conversations-pane {
      width: 320px;
      min-width: 280px;
      max-width: 420px;
      background-color: var(--color-surface);
      border-right: 1px solid var(--color-border);
      display: flex;
      flex-direction: column;
      height: 100%;
      overflow: hidden;
      flex-shrink: 0;
    }

    .pane-header {
      padding: var(--space-3) var(--space-4);
      display: flex;
      align-items: center;
      justify-content: space-between;
      border-bottom: 1px solid var(--color-border-subtle);
    }

    .pane-title {
      font-size: var(--font-size-md);
      font-weight: var(--font-weight-semibold);
      color: var(--color-text-primary);
    }

    .btn-new-message {
      display: inline-flex;
      align-items: center;
      gap: var(--space-1);
      padding: 4px var(--space-2);
      height: 28px;
      border-radius: var(--radius-sm);
      border: 1px solid var(--color-border);
      background-color: var(--color-surface);
      color: var(--color-text-primary);
      font-size: var(--font-size-xs);
      font-weight: var(--font-weight-medium);
      cursor: pointer;
      transition: background-color var(--motion-fast), border-color var(--motion-fast);
    }
    .btn-new-message:hover {
      background-color: var(--color-surface-hover);
      border-color: var(--color-border-hover);
    }


    .search-container {
      padding: var(--space-2) var(--space-4);
      position: relative;
    }

    .search-input-wrapper {
      position: relative;
      display: flex;
      align-items: center;
    }

    .search-icon-left {
      position: absolute;
      left: 10px;
      color: var(--color-text-muted);
      pointer-events: none;
    }

    .search-input {
      width: 100%;
      height: 36px;
      background-color: var(--color-surface-subtle);
      border: 1px solid var(--color-border);
      border-radius: var(--radius-sm);
      padding: 0 34px 0 32px;
      font-size: var(--font-size-sm);
      color: var(--color-text-primary);
      font-family: inherit;
      transition: border-color var(--motion-fast), background-color var(--motion-fast);
    }
    .search-input:focus {
      background-color: var(--color-surface);
      border-color: var(--color-border-focus);
    }
    .search-input::placeholder {
      color: var(--color-text-muted);
    }

    .search-clear-btn {
      position: absolute;
      right: 28px;
      width: 18px;
      height: 18px;
      border-radius: var(--radius-full);
      border: none;
      background: var(--color-border);
      color: var(--color-text-secondary);
      font-size: 11px;
      line-height: 1;
      display: none;
      align-items: center;
      justify-content: center;
      cursor: pointer;
    }
    .search-clear-btn:hover {
      background: var(--color-border-hover);
      color: var(--color-text-primary);
    }

    .kbd-shortcut-hint {
      position: absolute;
      right: 10px;
      font-size: 11px;
      font-family: var(--font-sans);
      color: var(--color-text-muted);
      background-color: var(--color-surface);
      border: 1px solid var(--color-border);
      border-radius: var(--radius-xs);
      padding: 1px 5px;
      pointer-events: none;
      line-height: 1.2;
    }


    .section-label {
      padding: var(--space-2) var(--space-4) var(--space-1);
      font-size: var(--font-size-xs);
      font-weight: var(--font-weight-medium);
      color: var(--color-text-muted);
      text-transform: capitalize;
    }


    .conversations-scroll {
      flex: 1;
      overflow-y: auto;
      list-style: none;
      padding: 0 var(--space-2) var(--space-2);
    }

    .conversation-item {
      height: 64px;
      padding: 0 var(--space-3);
      display: flex;
      align-items: center;
      gap: var(--space-3);
      border-radius: var(--radius-sm);
      cursor: pointer;
      position: relative;
      border: 1px solid transparent;
      border-left: 2px solid transparent;
      background-color: transparent;
      transition: background-color var(--motion-fast);
      margin-bottom: 2px;
      overflow: hidden;
    }
    .conversation-item:hover {
      background-color: var(--color-surface-hover);
    }
    .conversation-item.active {
      background-color: var(--color-surface-selected);
      border-left-color: var(--color-accent);
    }

    .avatar-wrapper {
      position: relative;
      width: 40px;
      height: 40px;
      border-radius: var(--radius-full);
      background-color: var(--color-border-subtle);
      overflow: hidden;
      flex-shrink: 0;
    }


    .memoji-avatar-badge {
      width: 100%;
      height: 100%;
      border-radius: var(--radius-full);
      overflow: hidden;
      display: flex;
      align-items: center;
      justify-content: center;
    }
    .memoji-avatar-badge .memoji-img {
      width: 88%;
      height: 88%;
      object-fit: contain;
      display: block;
    }

    .avatar-fallback {
      width: 100%;
      height: 100%;
      display: flex;
      align-items: center;
      justify-content: center;
      background-color: var(--color-accent-subtle);
      color: var(--color-accent);
      font-weight: var(--font-weight-semibold);
      font-size: var(--font-size-md);
    }

    .status-dot {
      width: 9px;
      height: 9px;
      border-radius: var(--radius-full);
      background-color: var(--color-status-online);
      border: 2px solid var(--color-surface);
      position: absolute;
      bottom: 0;
      right: 0;
    }
    .status-dot.offline {
      background-color: var(--color-status-offline);
    }
    .status-dot.away {
      background-color: var(--color-status-away);
    }
    .status-dot.unknown { background-color: var(--color-status-offline); }

    .conversation-info {
      flex: 1;
      min-width: 0;
      display: flex;
      flex-direction: column;
      gap: 2px;
      overflow: hidden;
    }

    .conversation-top {
      display: flex;
      align-items: baseline;
      justify-content: space-between;
      gap: var(--space-2);
    }

    .peer-name {
      font-size: var(--font-size-md);
      font-weight: var(--font-weight-medium);
      color: var(--color-text-primary);
      white-space: nowrap;
      overflow: hidden;
      text-overflow: ellipsis;
    }

    .timestamp-meta {
      font-size: var(--font-size-xs);
      color: var(--color-text-muted);
      white-space: nowrap;
      flex-shrink: 0;
    }

    .conversation-bottom {
      display: flex;
      align-items: center;
      justify-content: space-between;
      gap: var(--space-2);
    }

    .last-message-snippet {
      font-size: var(--font-size-sm);
      color: var(--color-text-secondary);
      white-space: nowrap;
      overflow: hidden;
      text-overflow: ellipsis;
      display: inline-flex;
      align-items: center;
      gap: var(--space-1);
    }

    .snippet-lock-icon {
      color: var(--color-text-muted);
      width: 12px;
      height: 12px;
    }

    .unread-badge {
      min-width: 18px;
      height: 18px;
      padding: 0 5px;
      border-radius: var(--radius-full);
      background-color: var(--color-accent);
      color: var(--color-accent-text);
      font-size: 11px;
      font-weight: var(--font-weight-semibold);
      display: inline-flex;
      align-items: center;
      justify-content: center;
      flex-shrink: 0;
    }


    .skeleton-item {
      height: 64px;
      padding: 0 var(--space-3);
      display: flex;
      align-items: center;
      gap: var(--space-3);
      margin-bottom: 2px;
    }
    .skeleton-avatar {
      width: 40px;
      height: 40px;
      border-radius: var(--radius-full);
      background-color: var(--color-border-subtle);
    }
    .skeleton-lines {
      flex: 1;
      display: flex;
      flex-direction: column;
      gap: 6px;
    }
    .skeleton-line {
      height: 12px;
      border-radius: var(--radius-xs);
      background-color: var(--color-border-subtle);
    }
    .skeleton-line.short {
      width: 60%;
    }
    .skeleton-line.tiny {
      width: 40%;
    }

    @keyframes skeletonPulse {
      0%, 100% { opacity: 0.6; }
      50% { opacity: 1; }
    }
    .skeleton-item, .skeleton-message-bubble {
      animation: skeletonPulse 1.6s ease-in-out infinite;
    }


    .empty-list-container {
      padding: var(--space-6) var(--space-4);
      text-align: center;
      color: var(--color-text-secondary);
      font-size: var(--font-size-sm);
    }
    .empty-list-title {
      font-weight: var(--font-weight-medium);
      color: var(--color-text-primary);
      margin-bottom: var(--space-1);
    }
    .empty-list-text {
      color: var(--color-text-muted);
      margin-bottom: var(--space-4);
      line-height: var(--line-height-normal);
    }


    .chat-pane {
      flex: 1;
      display: flex;
      flex-direction: column;
      height: 100%;
      min-height: 0;
      width: 100%;
      min-width: 0;
      max-width: 100%;
      background-color: var(--color-bg);
      position: relative;
      overflow: hidden;
    }


    .empty-chat-view {
      flex: 1;
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: center;
      padding: var(--space-6);
      text-align: center;
      width: 100%;
      min-width: 0;
      box-sizing: border-box;
    }

    .empty-chat-icon {
      width: 32px;
      height: 32px;
      color: var(--color-text-muted);
      margin-bottom: var(--space-3);
    }

    .empty-chat-title {
      font-size: var(--font-size-lg);
      font-weight: var(--font-weight-semibold);
      color: var(--color-text-primary);
      margin-bottom: var(--space-1);
    }

    .empty-chat-desc {
      font-size: var(--font-size-md);
      color: var(--color-text-secondary);
      margin-bottom: var(--space-4);
      max-width: 380px;
    }

    .btn-primary-action {
      display: inline-flex;
      align-items: center;
      gap: var(--space-2);
      padding: var(--space-2) var(--space-4);
      height: 36px;
      border-radius: var(--radius-sm);
      border: 1px solid var(--color-accent);
      background-color: var(--color-accent);
      color: var(--color-accent-text);
      font-size: var(--font-size-sm);
      font-weight: var(--font-weight-medium);
      cursor: pointer;
      transition: background-color var(--motion-fast);
    }
    .btn-primary-action:hover {
      background-color: var(--color-accent-hover);
    }


    .active-chat-container {
      display: flex;
      flex-direction: column;
      height: 100%;
      width: 100%;
      min-width: 0;
      max-width: 100%;
      overflow: hidden;
      min-height: 0;
    }


    .chat-header {
      min-height: 64px;
      height: auto;
      width: 100%;
      min-width: 0;
      box-sizing: border-box;
      padding: var(--space-2) var(--space-4);
      background-color: var(--color-surface);
      border-bottom: 1px solid var(--color-border);
      display: flex;
      align-items: center;
      justify-content: space-between;
      gap: var(--space-3);
      z-index: 10;
      flex-shrink: 0;
    }

    .chat-header-profile {
      display: flex;
      align-items: center;
      gap: var(--space-3);
      min-width: 0;
      flex: 1 1 auto;
    }

    .btn-mobile-back {
      display: none;
      width: 32px;
      height: 32px;
      border-radius: var(--radius-sm);
      border: 1px solid var(--color-border);
      background-color: var(--color-surface);
      color: var(--color-text-primary);
      align-items: center;
      justify-content: center;
      cursor: pointer;
      flex-shrink: 0;
    }
    .btn-mobile-back:hover {
      background-color: var(--color-surface-hover);
    }

    .chat-peer-avatar {
      width: 36px;
      height: 36px;
      border-radius: var(--radius-full);
      overflow: hidden;
      background-color: var(--color-border-subtle);
      flex-shrink: 0;
    }

    .chat-peer-meta {
      display: flex;
      flex-direction: column;
      gap: 1px;
      min-width: 0;
    }

    .chat-peer-name-row {
      display: flex;
      align-items: center;
      gap: var(--space-2);
      min-width: 0;
    }

    .chat-peer-title {
      font-size: var(--font-size-md);
      font-weight: var(--font-weight-semibold);
      color: var(--color-text-primary);
      white-space: nowrap;
      overflow: hidden;
      text-overflow: ellipsis;
    }

    .chat-peer-sub {
      font-size: var(--font-size-xs);
      color: var(--color-text-secondary);
      display: flex;
      align-items: center;
      gap: var(--space-2);
    }

    .inline-status {
      display: inline-flex;
      align-items: center;
      gap: 4px;
      font-size: var(--font-size-xs);
      color: var(--color-status-online);
    }
    .inline-status.offline {
      color: var(--color-status-offline);
    }
    .inline-status.away {
      color: var(--color-status-away);
    }
    .inline-status.unknown { color: var(--color-text-secondary); }


    .encryption-badge {
      display: inline-flex;
      align-items: center;
      gap: 4px;
      padding: 2px 6px;
      border-radius: var(--radius-sm);
      border: 1px solid var(--color-border);
      background-color: var(--color-surface-subtle);
      color: var(--color-text-secondary);
      font-size: var(--font-size-xs);
      cursor: pointer;
      position: relative;
    }
    .encryption-badge:hover {
      background-color: var(--color-surface-hover);
      color: var(--color-text-primary);
    }

    .encryption-popover {
      display: none;
      position: absolute;
      top: calc(100% + 8px);
      left: 0;
      width: 290px;
      padding: var(--space-3);
      border-radius: var(--radius-md);
      background-color: var(--color-surface);
      border: 1px solid var(--color-border);
      box-shadow: var(--shadow-overlay);
      font-size: var(--font-size-xs);
      color: var(--color-text-secondary);
      line-height: var(--line-height-normal);
      z-index: 100;
      text-align: left;
    }
    .encryption-popover.active {
      display: block;
    }
    .encryption-popover strong {
      display: block;
      color: var(--color-text-primary);
      margin-bottom: 4px;
    }

    .chat-header-actions {
      display: flex;
      align-items: center;
      gap: var(--space-2);
      flex: 0 0 auto;
    }

    .btn-action-ghost {
      height: 30px;
      padding: 0 var(--space-3);
      border-radius: var(--radius-sm);
      border: 1px solid var(--color-border);
      background-color: var(--color-surface);
      color: var(--color-text-secondary);
      font-size: var(--font-size-xs);
      font-weight: var(--font-weight-medium);
      cursor: pointer;
      transition: background-color var(--motion-fast), color var(--motion-fast), border-color var(--motion-fast);
    }
    .btn-action-ghost:hover {
      background-color: var(--color-surface-hover);
      color: var(--color-text-primary);
    }
    .btn-action-ghost.danger:hover {
      background-color: var(--color-danger-subtle);
      color: var(--color-danger);
      border-color: var(--color-danger);
    }
    .btn-action-ghost:focus-visible {
      outline: 2px solid var(--color-accent) !important;
      outline-offset: 2px !important;
    }

    #reportReasonSelect,
    #reportDetailsText {
      background-color: var(--color-surface);
      border: 1px solid var(--color-border);
      color: var(--color-text-primary);
      transition: border-color var(--motion-fast), box-shadow var(--motion-fast);
    }

    #reportReasonSelect:hover,
    #reportDetailsText:hover {
      border-color: var(--color-border-hover);
    }

    #reportReasonSelect:focus,
    #reportReasonSelect:focus-visible,
    #reportDetailsText:focus,
    #reportDetailsText:focus-visible {
      outline: none;
      border-color: var(--color-border-focus);
      box-shadow: 0 0 0 2px var(--color-border-focus);
    }

    select option {
      background-color: var(--color-surface);
      color: var(--color-text-primary);
    }


    .offline-banner {
      display: none;
      background-color: var(--color-warning-subtle);
      border-bottom: 1px solid var(--color-border);
      padding: var(--space-2) var(--space-4);
      font-size: var(--font-size-xs);
      color: var(--color-text-primary);
      align-items: center;
      justify-content: space-between;
      gap: var(--space-2);
    }
    .offline-banner.active {
      display: flex;
    }
    .offline-banner-left {
      display: flex;
      align-items: center;
      gap: var(--space-2);
    }
    .offline-retry-btn {
      background: none;
      border: none;
      color: var(--color-accent);
      font-weight: var(--font-weight-medium);
      font-size: var(--font-size-xs);
      cursor: pointer;
      text-decoration: underline;
    }


    .chat-messages-scroll {
      flex: 1;
      min-height: 0;
      overflow-y: auto;
      overscroll-behavior-y: contain;
      -webkit-overflow-scrolling: touch;
      padding: var(--space-4) var(--space-6);
      display: flex;
      flex-direction: column;
      gap: 12px;
      scroll-behavior: smooth;
    }


    .date-separator {
      display: flex;
      align-items: center;
      justify-content: center;
      margin: var(--space-3) 0;
      position: relative;
    }
    .date-separator::before {
      content: "";
      position: absolute;
      left: 0;
      right: 0;
      top: 50%;
      height: 1px;
      background-color: var(--color-border);
      z-index: 1;
    }
    .date-separator-label {
      position: relative;
      z-index: 2;
      background-color: var(--color-bg);
      padding: 0 var(--space-3);
      font-size: var(--font-size-xs);
      font-weight: var(--font-weight-medium);
      color: var(--color-text-muted);
    }


    .message-row {
      display: flex;
      flex-direction: column;
      max-width: 70%;
    }
    .message-row.received {
      align-self: flex-start;
      align-items: flex-start;
    }
    .message-row.sent {
      align-self: flex-end;
      align-items: flex-end;
    }

    .bubble-container {
      display: flex;
      align-items: flex-end;
      gap: var(--space-2);
      width: 100%;
    }
    .message-row.sent .bubble-container {
      flex-direction: row-reverse;
    }

    .message-bubble {
      padding: 8px var(--space-3);
      font-size: var(--font-size-md);
      line-height: var(--line-height-normal);
      word-break: break-word;
      border-radius: var(--radius-md);
      font-weight: var(--font-weight-regular);
      position: relative;
    }

    .message-row.received .message-bubble {
      background-color: var(--color-msg-rcvd-bg);
      color: var(--color-msg-rcvd-text);
      border: 1px solid var(--color-msg-rcvd-border);
      border-bottom-left-radius: 2px;
    }

    .message-row.sent .message-bubble {
      background-color: var(--color-msg-sent-bg);
      color: var(--color-msg-sent-text);
      border: 1px solid var(--color-msg-sent-border);
      border-bottom-right-radius: 2px;
    }

    .message-meta {
      display: flex;
      align-items: center;
      gap: 4px;
      margin-top: 2px;
      font-size: var(--font-size-xs);
      color: var(--color-text-muted);
    }
    .message-row.sent .message-meta {
      justify-content: flex-end;
      color: var(--color-text-muted);
    }

    .msg-status-icon {
      width: 12px;
      height: 12px;
      color: var(--color-text-muted);
    }
    .msg-status-failed {
      color: var(--color-danger);
      cursor: pointer;
    }


    .message-row + .message-row.same-sender {
      margin-top: -8px;
    }


    .composer-container {
      padding: var(--space-3) var(--space-4) max(var(--space-3), env(safe-area-inset-bottom, 0px));
      background-color: var(--color-surface);
      border-top: 1px solid var(--color-border);
      flex-shrink: 0;
      width: 100%;
      min-width: 0;
      box-sizing: border-box;
    }

    .composer-card {
      border: 1px solid var(--color-border);
      border-radius: var(--radius-md);
      background-color: var(--color-surface);
      display: flex;
      flex-direction: column;
      width: 100%;
      min-width: 0;
      box-sizing: border-box;
      transition: border-color var(--motion-fast), box-shadow var(--motion-fast);
    }
    .composer-card:focus-within {
      border-color: var(--color-border-focus);
    }

    .composer-textarea {
      width: 100%;
      min-height: 40px;
      max-height: 140px;
      border: none !important;
      background: transparent;
      padding: var(--space-2) var(--space-3);
      font-size: var(--font-size-md);
      font-family: inherit;
      color: var(--color-text-primary);
      resize: none;
      outline: none !important;
      box-shadow: none !important;
      line-height: var(--line-height-normal);
    }
    .composer-textarea:focus, .composer-textarea:focus-visible {
      outline: none !important;
      border: none !important;
      box-shadow: none !important;
    }
    .composer-textarea::placeholder {
      color: var(--color-text-muted);
    }

    .composer-toolbar {
      display: flex;
      align-items: center;
      justify-content: space-between;
      padding: var(--space-1) var(--space-2) var(--space-2);
    }

    .composer-tools-left {
      display: flex;
      align-items: center;
      gap: 4px;
    }

    .composer-tool-btn {
      width: 28px;
      height: 28px;
      border: none;
      background: transparent;
      color: var(--color-text-secondary);
      border-radius: var(--radius-sm);
      display: inline-flex;
      align-items: center;
      justify-content: center;
      cursor: pointer;
      transition: background-color var(--motion-fast), color var(--motion-fast);
    }
    .composer-tool-btn:hover {
      background-color: var(--color-surface-hover);
      color: var(--color-text-primary);
    }

    .composer-tools-right {
      display: flex;
      align-items: center;
      gap: var(--space-3);
    }

    .composer-counter {
      font-size: var(--font-size-xs);
      color: var(--color-text-muted);
    }

    .btn-send {
      height: 32px;
      padding: 0 var(--space-3);
      border-radius: var(--radius-sm);
      border: 1px solid var(--color-accent);
      background-color: var(--color-accent);
      color: var(--color-accent-text);
      font-size: var(--font-size-sm);
      font-weight: var(--font-weight-medium);
      cursor: pointer;
      display: inline-flex;
      align-items: center;
      gap: 6px;
      transition: background-color var(--motion-fast), opacity var(--motion-fast);
    }
    .btn-send:disabled {
      opacity: 0.45;
      cursor: not-allowed;
      border-color: var(--color-border);
      background-color: var(--color-border);
      color: var(--color-text-muted);
    }
    .btn-send:not(:disabled):hover {
      background-color: var(--color-accent-hover);
    }


    .modal-backdrop {
      position: fixed;
      inset: 0;
      background-color: var(--color-modal-backdrop);
      display: none;
      align-items: center;
      justify-content: center;
      z-index: 1000;
      padding: var(--space-4);
    }
    .modal-backdrop.active {
      display: flex;
    }

    .modal-box {
      width: 100%;
      max-width: 440px;
      background-color: var(--bg-modal);
      border: 1px solid var(--color-border);
      border-radius: var(--radius-md);
      box-shadow: var(--shadow-overlay);
      overflow: hidden;
      display: flex;
      flex-direction: column;
      max-height: 80vh;
    }

    .modal-header {
      padding: var(--space-3) var(--space-4);
      border-bottom: 1px solid var(--color-border);
      display: flex;
      align-items: center;
      justify-content: space-between;
    }

    .modal-title {
      font-size: var(--font-size-md);
      font-weight: var(--font-weight-semibold);
      color: var(--color-text-primary);
    }

    .modal-search-wrap {
      padding: var(--space-3) var(--space-4) var(--space-2);
      border-bottom: 1px solid var(--color-border-subtle);
    }

    .modal-list-scroll {
      flex: 1;
      overflow-y: auto;
      padding: var(--space-2);
    }

    .modal-student-row {
      display: flex;
      align-items: center;
      gap: var(--space-3);
      padding: var(--space-2) var(--space-3);
      border-radius: var(--radius-sm);
      cursor: pointer;
      border: 1px solid transparent;
      transition: background-color var(--motion-fast);
    }
    .modal-student-row:hover, .modal-student-row:focus-visible {
      background-color: var(--color-surface-hover);
    }

    .modal-student-avatar {
      width: 36px;
      height: 36px;
      border-radius: var(--radius-full);
      overflow: hidden;
      background-color: var(--color-border-subtle);
      flex-shrink: 0;
    }

    .modal-student-info {
      flex: 1;
      min-width: 0;
    }

    .modal-student-name {
      font-size: var(--font-size-md);
      font-weight: var(--font-weight-medium);
      color: var(--color-text-primary);
    }

    .modal-student-dept {
      font-size: var(--font-size-xs);
      color: var(--color-text-secondary);
    }

    .modal-student-presence {
      font-size: var(--font-size-xs);
      color: var(--color-status-offline);
    }
    .modal-student-presence.online { color: var(--color-status-online); }
    .modal-student-presence.away { color: var(--color-status-away); }


    .toast-message {
      position: fixed;
      bottom: 24px;
      left: 50%;
      transform: translateX(-50%);
      background-color: var(--color-text-primary);
      color: var(--color-text-inverse);
      padding: var(--space-2) var(--space-4);
      border-radius: var(--radius-sm);
      font-size: var(--font-size-sm);
      box-shadow: var(--shadow-overlay);
      z-index: 10000;
      opacity: 0;
      transition: opacity var(--motion-fast);
      pointer-events: none;
    }
    .toast-message.active {
      opacity: 1;
    }


    @media (min-width: 769px) and (max-width: 1024px) {
      .conversations-pane {
        width: clamp(260px, 32vw, 320px);
        min-width: 260px;
      }
    }


    @media (max-width: 768px) {
      html,
      body {
        width: 100%;
        max-width: 100%;
        overflow: hidden;
      }
      .messages-layout {
        height: calc(100vh - var(--header-height, 56px));
        height: calc(100dvh - var(--header-height, 56px) - env(safe-area-inset-top, 0px));
        min-height: 0;
        padding-bottom: env(safe-area-inset-bottom, 0px);
      }
      .app-header {
        padding: env(safe-area-inset-top, 0px) var(--space-3) 0;
      }
      .header-title {
        font-size: var(--font-size-md);
      }
      .header-user-badge {
        max-width: 44vw;
        padding: var(--space-1) var(--space-2);
        gap: var(--space-1);
      }
      .header-user-role {
        max-width: 92px;
      }
      .conversations-pane {
        width: 100%;
        max-width: 100%;
        min-width: 100%;
      }
      .pane-header {
        padding: var(--space-3);
      }
      .btn-new-message {
        min-height: 44px;
      }
      .search-input {
        height: 44px;
      }
      .search-clear-btn {
        width: 32px;
        height: 32px;
        right: 24px;
      }
      .kbd-shortcut-hint {
        display: none;
      }
      .chat-pane {
        display: none;
        width: 100%;
      }
      .messages-layout.mobile-chat-open .conversations-pane {
        display: none !important;
        width: 0 !important;
        min-width: 0 !important;
        max-width: 0 !important;
        padding: 0 !important;
        border: none !important;
      }
      .messages-layout.mobile-chat-open .chat-pane {
        display: flex !important;
        width: 100% !important;
        min-width: 0 !important;
        max-width: 100% !important;
      }
      .chat-header {
        padding: var(--space-2) var(--space-3);
        flex-wrap: wrap;
        row-gap: var(--space-2);
      }
      .chat-header-profile {
        display: flex !important;
        align-items: center !important;
        flex-direction: row !important;
        min-width: 0 !important;
        flex: 1 1 180px !important;
        gap: var(--space-2) !important;
      }
      .chat-peer-meta {
        min-width: 0 !important;
        overflow: hidden !important;
      }
      .chat-peer-name-row {
        flex-wrap: wrap;
      }
      .btn-mobile-back {
        display: inline-flex !important;
        width: 44px;
        height: 44px;
        flex-shrink: 0 !important;
      }
      .chat-peer-avatar {
        width: 36px;
        height: 36px;
      }
      .chat-peer-title {
        font-size: var(--font-size-sm);
      }
      .encryption-badge span {
        display: none;
      }
      .encryption-badge {
        padding: 3px;
      }
      .chat-messages-scroll {
        padding: var(--space-3);
      }
      .chat-header-actions {
        margin-left: auto;
      }
      .chat-header-actions .btn-action-ghost {
        min-height: 44px;
      }
      .composer-container {
        padding-left: var(--space-3);
        padding-right: var(--space-3);
        padding-bottom: max(var(--space-2), env(safe-area-inset-bottom, 0px));
      }
      .composer-textarea {
        min-height: 44px;
        font-size: 16px;
      }
      .btn-send {
        min-height: 44px;
        min-width: 76px;
      }
      .message-row {
        max-width: 86%;
      }
      .messages-keyboard-open .chat-header {
        padding-top: 4px;
        padding-bottom: 4px;
      }
      .messages-keyboard-open .chat-messages-scroll {
        padding-top: 4px;
        padding-bottom: 4px;
      }
    }


    .connection-consent-panel {
      display: flex;
      align-items: center;
      justify-content: space-between;
      gap: 12px;
      padding: 10px 16px;
      border-top: 1px solid var(--color-border);
      border-bottom: 1px solid var(--color-border);
      background: var(--color-surface-subtle);
      color: var(--color-text-primary);
      font-size: var(--font-size-sm);
      line-height: 1.45;
    }
    .connection-consent-panel[hidden] { display: none; }
    .connection-consent-message { margin: 0; }
    .connection-consent-actions { display: flex; flex-wrap: wrap; gap: 8px; flex-shrink: 0; }
    .connection-consent-actions button {
      min-height: 36px;
      padding: 7px 12px;
      border: 1px solid var(--color-border-focus);
      border-radius: 7px;
      background: var(--color-text-primary);
      color: var(--color-bg);
      font: inherit;
      font-weight: 650;
      cursor: pointer;
    }
    .connection-consent-actions button.secondary {
      background: var(--color-bg);
      color: var(--color-text-primary);
    }
    .connection-consent-actions button:disabled { opacity: .6; cursor: wait; }
    @media (max-width: 640px) {
      .connection-consent-panel { align-items: flex-start; flex-direction: column; padding: 10px 12px; }
      .connection-consent-actions { width: 100%; }
      .connection-consent-actions button { flex: 1 1 auto; }
    }


    @media (prefers-reduced-motion: reduce) {
      *, *::before, *::after {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
      }
    }