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

      html {
        scroll-behavior: smooth;
      }

      body {
        font-family: -apple-system, BlinkMacSystemFont, "Segoe UI",
          "Helvetica Neue", sans-serif;
        background-color: #ffffff;
        color: #333;
        -webkit-font-smoothing: antialiased;
        -moz-osx-font-smoothing: grayscale;
        -webkit-tap-highlight-color: transparent;
      }

      .container {
        display: flex;
        height: 100vh;
        background-color: #ffffff;
      }

      /* Sidebar */
      .sidebar {
        width: 280px;
        background: #ffffff;
        border-right: 1px solid #eff0f1;
        padding: 32px 0;
        position: fixed;
        height: 100vh;
        overflow-y: auto;
        box-shadow: 0 0 20px rgba(0, 0, 0, 0.06);
        display: flex;
        flex-direction: column;
        transition: width 0.3s ease, padding 0.3s ease;
        z-index: 999;
      }

      .sidebar.collapsed {
        width: 80px;
        padding: 16px 0;
      }

      .sidebar.collapsed .sidebar-header-content {
        display: none;
      }

      .sidebar.collapsed .sidebar-header {
        padding: 12px 8px;
        margin-bottom: 20px;
        justify-content: center;
      }

      .sidebar.collapsed .sidebar-footer {
        display: none;
      }

      .sidebar.collapsed .tabs {
        padding: 0;
        gap: 12px;
        align-items: center;
      }

      .sidebar.collapsed .tab-button {
        padding: 12px;
        font-size: 24px;
        width: 48px;
        height: 48px;
        justify-content: center;
        align-items: center;
        border-radius: 12px;
        gap: 0;
        margin: 0 auto;
      }

      .sidebar.collapsed .tab-label {
        display: none;
      }

      .sidebar-content {
        flex: 1;
        overflow-y: auto;
      }

      .sidebar-footer {
        padding: 16px 28px;
        border-top: 1px solid #eff0f1;
        text-align: center;
        font-size: 12px;
        color: #ccc;
      }

      .sidebar-header {
        padding: 20px 28px 32px;
        margin-bottom: 12px;
        display: flex;
        align-items: flex-start;
        justify-content: space-between;
      }

      .sidebar-header-content {
        flex: 1;
      }

      .sidebar-header h1 {
        font-size: 28px;
        color: #1e3799;
        font-weight: 800;
        letter-spacing: -0.5px;
        font-family: -apple-system, BlinkMacSystemFont, "Segoe UI",
          "Helvetica Neue", sans-serif;
      }

      .sidebar-header p {
        font-size: 14px;
        color: #999;
        margin-top: 6px;
        font-weight: 500;
        font-family: -apple-system, BlinkMacSystemFont, "Segoe UI",
          "Helvetica Neue", sans-serif;
      }

      .toggle-button {
        width: 40px;
        height: 40px;
        background: transparent;
        border: none;
        cursor: pointer;
        display: flex;
        align-items: center;
        justify-content: center;
        font-size: 20px;
        transition: all 0.25s ease;
        flex-shrink: 0;
      }

      .toggle-button:hover {
        background-color: #f5f5f5;
        border-radius: 8px;
      }

      .tabs {
        display: flex;
        flex-direction: column;
        gap: 8px;
        padding: 0 16px;
      }

      .tab-button {
        padding: 14px 18px;
        background: transparent;
        border: none;
        text-align: left;
        cursor: pointer;
        font-size: 16px;
        color: #555;
        transition: all 0.25s ease;
        font-weight: 500;
        border-radius: 10px;
        position: relative;
        font-family: -apple-system, BlinkMacSystemFont, "Segoe UI",
          "Helvetica Neue", sans-serif;
        white-space: nowrap;
        display: flex;
        align-items: center;
        gap: 8px;
        min-height: 44px;
        -webkit-user-select: none;
        user-select: none;
        -webkit-tap-highlight-color: transparent;
      }

      .tab-icon {
        flex-shrink: 0;
        font-size: 20px;
      }

      .tab-label {
        flex: 1;
      }

      .tab-button:hover {
        background-color: #f5f5f5;
        color: #1e3799;
      }

      .tab-button.active {
        background-color: #e8f0fe;
        color: #1e3799;
        font-weight: 600;
      }

      /* Main Content */
      .main-content {
        margin-left: 280px;
        flex: 1;
        display: flex;
        flex-direction: column;
        overflow: hidden;
        transition: margin-left 0.3s ease;
      }

      .sidebar.collapsed ~ .main-content {
        margin-left: 80px;
      }

      .content-header {
        padding: 30px 40px;
        border-bottom: 1px solid #e9ecef;
        background-color: #ffffff;
      }

      .content-header h2 {
        font-size: 28px;
        color: #1a1a1a;
        margin-bottom: 8px;
      }

      .content-header p {
        font-size: 14px;
        color: #999;
      }

      .content-body {
        flex: 1;
        overflow-y: auto;
        padding: 0;
        background-color: #ffffff;
      }

      .iframe-content {
        width: 100%;
        height: 100%;
        border: none;
      }

      /* Responsive */
      @media (max-width: 1024px) {
        .sidebar {
          width: 240px;
        }

        .main-content {
          margin-left: 240px;
        }

        .sidebar.collapsed ~ .main-content {
          margin-left: 80px;
        }
      }

      @media (max-width: 768px) {
        .sidebar {
          width: 200px;
          padding: 24px 0;
        }

        .main-content {
          margin-left: 200px;
        }

        .sidebar.collapsed {
          width: 70px;
          padding: 12px 0;
        }

        .sidebar.collapsed ~ .main-content {
          margin-left: 70px;
        }

        .sidebar-header {
          padding: 16px 20px 24px;
        }

        .sidebar-header h1 {
          font-size: 22px;
        }

        .sidebar-header p {
          font-size: 13px;
        }

        .tab-button {
          font-size: 15px;
          padding: 12px 16px;
          min-height: 44px;
        }

        .tab-icon {
          font-size: 22px;
        }

        .content-header {
          padding: 24px 20px;
        }

        .content-header h2 {
          font-size: 22px;
        }

        .content-header p {
          font-size: 13px;
        }
      }

      @media (max-width: 600px) {
        body {
          font-size: 14px;
        }

        .sidebar {
          width: 160px;
          padding: 20px 0;
        }

        .main-content {
          margin-left: 160px;
        }

        .sidebar.collapsed {
          width: 60px;
          padding: 12px 0;
        }

        .sidebar.collapsed ~ .main-content {
          margin-left: 60px;
        }

        .sidebar-header {
          padding: 14px 14px 18px;
        }

        .sidebar-header h1 {
          font-size: 20px;
        }

        .sidebar-header p {
          font-size: 11px;
        }

        .toggle-button {
          width: 36px;
          height: 36px;
          font-size: 18px;
        }

        .tab-button {
          padding: 10px 14px;
          font-size: 14px;
          min-height: 44px;
          border-radius: 8px;
        }

        .tab-icon {
          font-size: 20px;
          flex-shrink: 0;
        }

        .tab-label {
          font-size: 13px;
        }

        .sidebar-footer {
          padding: 12px 12px;
          font-size: 11px;
        }

        .content-header {
          padding: 16px;
          margin-bottom: 0;
        }

        .content-header h2 {
          font-size: 18px;
          margin-bottom: 6px;
        }

        .content-header p {
          font-size: 12px;
        }

        .content-body {
          margin-top: 0;
        }
      }

      @media (max-width: 480px) {
        .sidebar {
          width: 140px;
        }

        .main-content {
          margin-left: 140px;
        }

        .sidebar.collapsed {
          width: 55px;
        }

        .sidebar.collapsed ~ .main-content {
          margin-left: 55px;
        }

        .sidebar-header {
          padding: 12px 10px 16px;
        }

        .sidebar-header h1 {
          font-size: 18px;
        }

        .sidebar-header p {
          display: none;
        }

        .tab-button {
          padding: 8px 12px;
          font-size: 13px;
          min-height: 40px;
        }

        .tab-icon {
          font-size: 18px;
        }

        .content-header {
          padding: 12px 12px;
        }

        .content-header h2 {
          font-size: 16px;
        }
      }