:root {
      --primary: #2563EB;
      --secondary: #14B8A6;
      --sidebar-width: 272px;
      --sidebar-collapsed: 78px;
      --header-height: 70px;
  }

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

  body {
      font-family: 'Inter', sans-serif;
      background: #F1F5F9;
      overflow-x: hidden;
  }

  .dark body,
  html.dark body {
      background: #0F172A;
  }

  ::-webkit-scrollbar {
      width: 5px;
      height: 5px;
  }

  ::-webkit-scrollbar-track {
      background: transparent;
  }

  ::-webkit-scrollbar-thumb {
      background: #94a3b8;
      border-radius: 10px;
  }

  .dark ::-webkit-scrollbar-thumb {
      background: #475569;
  }

  .sidebar {
      width: var(--sidebar-width);
      transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
      z-index: 50;
  }

  .sidebar.collapsed {
      width: var(--sidebar-collapsed);
  }

  .sidebar.collapsed .sidebar-text,
  .sidebar.collapsed .sidebar-logo-text,
  .sidebar.collapsed .sidebar-badge,
  .sidebar.collapsed .sidebar-submenu,
  .sidebar.collapsed .menu-section-title,
  .sidebar.collapsed .sidebar-upgrade {
      display: none;
  }

  .sidebar.collapsed .sidebar-link {
      justify-content: center;
      padding: 10px 12px;
  }

  .sidebar.collapsed .sidebar-logo {
      justify-content: center;
  }

  .sidebar-link {
      transition: all 0.2s ease;
      position: relative;
      border-radius: 10px;
  }

  .sidebar-link::before {
      content: '';
      position: absolute;
      left: 0;
      top: 0;
      height: 100%;
      width: 3px;
      background: var(--primary);
      transform: scaleY(0);
      transition: transform 0.2s ease;
      border-radius: 0 3px 3px 0;
  }

  .sidebar-link:hover::before,
  .sidebar-link.active::before {
      transform: scaleY(1);
  }

  .main-content {
      margin-left: var(--sidebar-width);
      transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
      min-height: 100vh;
  }

  .main-content.expanded {
      margin-left: var(--sidebar-collapsed);
  }

  @media (max-width:1023px) {
      .main-content {
          margin-left: 0 !important;
      }
  }

  .header {
      height: var(--header-height);
  }

  .header.scrolled {
      box-shadow: 0 2px 15px rgba(0, 0, 0, 0.06);
  }

  .dark .header.scrolled {
      box-shadow: 0 2px 15px rgba(0, 0, 0, 0.25);
  }

  .gradient-mixed {
      background: linear-gradient(135deg, #2563EB, #14B8A6);
  }

  .dropdown-menu {
      transform-origin: top right;
  }

  .dropdown-menu.show {
      animation: ddIn 0.25s ease forwards;
  }

  @keyframes ddIn {
      from {
          opacity: 0;
          transform: scale(0.95) translateY(-4px);
      }

      to {
          opacity: 1;
          transform: scale(1) translateY(0);
      }
  }

  .modal-overlay {
      position: fixed;
      inset: 0;
      z-index: 70;
      background: rgba(0, 0, 0, 0.6);
      backdrop-filter: blur(4px);
      opacity: 0;
      visibility: hidden;
      transition: all 0.3s ease;
      display: flex;
      align-items: center;
      justify-content: center;
      padding: 16px;
  }

  .modal-overlay.active {
      opacity: 1;
      visibility: visible;
  }

  .modal-box {
      background: white;
      border-radius: 20px;
      width: 100%;
      max-height: 90vh;
      overflow-y: auto;
      box-shadow: 0 25px 60px rgba(0, 0, 0, 0.15);
      transform: scale(0.9) translateY(20px);
      opacity: 0;
      transition: all 0.35s cubic-bezier(0.34, 1.56, 0.64, 1);
  }

  .dark .modal-box {
      background: #1E293B;
  }

  .modal-overlay.active .modal-box {
      transform: scale(1) translateY(0);
      opacity: 1;
  }

  .toast-item {
      animation: toastSlide 0.5s cubic-bezier(0.34, 1.56, 0.64, 1) forwards;
      pointer-events: auto;
  }

  @keyframes toastSlide {
      from {
          opacity: 0;
          transform: translateX(100%);
      }

      to {
          opacity: 1;
          transform: translateX(0);
      }
  }

  .toast-item.removing {
      animation: toastHide 0.3s ease forwards;
  }

  @keyframes toastHide {
      to {
          opacity: 0;
          transform: translateX(100%);
      }
  }

  .page-loader {
      position: fixed;
      inset: 0;
      z-index: 9999;
      display: flex;
      align-items: center;
      justify-content: center;
      transition: opacity 0.5s ease, visibility 0.5s ease;
  }

  .page-loader.done {
      opacity: 0;
      visibility: hidden;
      pointer-events: none;
  }

  .loader-ring {
      width: 44px;
      height: 44px;
      border: 3px solid rgba(37, 99, 235, 0.2);
      border-top-color: #2563EB;
      border-radius: 50%;
      animation: spin 0.7s linear infinite;
  }

  @keyframes spin {
      to {
          transform: rotate(360deg);
      }
  }

  @keyframes settings-spin {
      0% {
          transform: rotate(0deg);
      }

      100% {
          transform: rotate(360deg);
      }
  }

  .settings-spin {
      animation: settings-spin 20s linear infinite;
  }

  .settings-nav-item {
      transition: all 0.2s ease;
      position: relative;
  }

  .settings-nav-item.active {
      background: linear-gradient(135deg, rgba(37, 99, 235, 0.1), rgba(20, 184, 166, 0.05));
      color: #2563EB;
  }

  .dark .settings-nav-item.active {
      background: linear-gradient(135deg, rgba(37, 99, 235, 0.2), rgba(20, 184, 166, 0.1));
      color: #60a5fa;
  }

  .settings-nav-item.active::before {
      content: '';
      position: absolute;
      left: 0;
      top: 0;
      height: 100%;
      width: 3px;
      background: linear-gradient(180deg, #2563EB, #14B8A6);
      border-radius: 0 3px 3px 0;
  }

  .toggle-switch {
      position: relative;
      display: inline-block;
      width: 44px;
      height: 24px;
      cursor: pointer;
  }

  .toggle-switch input {
      opacity: 0;
      width: 0;
      height: 0;
  }

  .toggle-slider {
      position: absolute;
      inset: 0;
      background: #CBD5E1;
      border-radius: 24px;
      transition: 0.3s;
  }

  .dark .toggle-slider {
      background: #475569;
  }

  .toggle-slider:before {
      content: '';
      position: absolute;
      height: 18px;
      width: 18px;
      left: 3px;
      bottom: 3px;
      background: white;
      border-radius: 50%;
      transition: 0.3s;
      box-shadow: 0 2px 6px rgba(0, 0, 0, 0.2);
  }

  .toggle-switch input:checked+.toggle-slider {
      background: linear-gradient(135deg, #2563EB, #14B8A6);
  }

  .toggle-switch input:checked+.toggle-slider:before {
      transform: translateX(20px);
  }

  .color-swatch {
      width: 32px;
      height: 32px;
      border-radius: 50%;
      cursor: pointer;
      transition: all 0.2s ease;
      border: 3px solid transparent;
  }

  .color-swatch:hover {
      transform: scale(1.1);
  }

  .color-swatch.selected {
      transform: scale(1.15);
      box-shadow: 0 4px 12px rgba(0, 0, 0, 0.2);
  }

  .theme-card {
      transition: all 0.3s ease;
      cursor: pointer;
  }

  .theme-card:hover {
      transform: translateY(-2px);
  }

  .theme-card.active {
      border-color: #2563EB !important;
      box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.15);
  }

  .setting-card {
      transition: all 0.2s ease;
  }

  .setting-card:hover {
      background: rgba(37, 99, 235, 0.03);
  }

  .dark .setting-card:hover {
      background: rgba(37, 99, 235, 0.08);
  }

  .session-active {
      border-color: #22C55E !important;
  }

  .session-active::before {
      content: '';
      position: absolute;
      top: 12px;
      right: 12px;
      width: 8px;
      height: 8px;
      background: #22C55E;
      border-radius: 50%;
      box-shadow: 0 0 0 4px rgba(34, 197, 94, 0.2);
      animation: pulse-dot 2s infinite;
  }

  @keyframes pulse-dot {

      0%,
      100% {
          box-shadow: 0 0 0 0 rgba(34, 197, 94, 0.4);
      }

      50% {
          box-shadow: 0 0 0 8px rgba(34, 197, 94, 0);
      }
  }

  .language-flag {
      transition: all 0.2s ease;
      cursor: pointer;
  }

  .language-flag:hover {
      transform: translateY(-2px);
  }

  .language-flag.selected {
      background: linear-gradient(135deg, rgba(37, 99, 235, 0.1), rgba(20, 184, 166, 0.1));
      border-color: #2563EB !important;
  }