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

      body {
        font-family: "Cairo", "Inter", sans-serif;
        background: hsl(220 25% 8% / 1);
        color: #fff;
        overflow-x: hidden;
      }

      body::before {
        content: "";
        position: fixed;
        top: 0;
        left: 0;
        right: 0;
        bottom: 0;
        /*background: 
                linear-gradient(to right, hsl(240 10% 20%) 1px, transparent 1px),
                linear-gradient(to bottom, hsl(240 10% 20%) 1px, transparent 1px);*/
        background-size: 50px 50px;
        pointer-events: none;
        z-index: 0;
      }

      nav {
        display: flex;
        justify-content: space-between;
        align-items: center;
        padding: 1.5rem 5%;
        position: fixed;
        width: 100%;
        top: 0;
        backdrop-filter: blur(10px);
        z-index: 1000;
        border-bottom: 1px solid rgba(124, 58, 237, 0.1);
        background: rgba(10, 14, 39, 0.8);
      }

      .logo {
        display: flex;
        align-items: center;
        cursor: pointer;
        transition: transform 0.3s ease;
      }

      .logo:hover {
        transform: scale(1.05);
      }

      .nav-start-lang {
        display: flex;
        align-items: center;
        gap: 12px;
      }

      .mobile-menu-btn {
        display: none;
        background: none;
        border: none;
        color: white;
        font-size: 1.5rem;
        cursor: pointer;
        z-index: 1001;
      }

      .mobile-menu-btn.active .hamburger-line:nth-child(2) {
        opacity: 0;
      }

      .mobile-menu-btn.active .hamburger-line:nth-child(1) {
        transform: translateY(6px) rotate(45deg);
      }

      .mobile-menu-btn.active .hamburger-line:nth-child(3) {
        transform: translateY(-6px) rotate(-45deg);
      }

      .hamburger {
        width: 25px;
        height: 15px;
        display: flex;
        flex-direction: column;
        justify-content: space-between;
      }

      .hamburger-line {
        width: 25px;
        height: 3px;
        background: white;
        border-radius: 999px;
        transition: all 0.3s;
      }

      .logo img {
        height: 40px;
        width: auto;
        max-width: 150px;
        object-fit: contain;
      }

      .nav-links {
        display: flex;
        gap: 2rem;
        list-style: none;
      }

      .nav-links a {
        color: #fff;
        text-decoration: none;
        transition: color 0.3s;
        display: flex;
        align-items: center;
        gap: 8px;
      }

      .nav-links a i {
        width: 20px;
        text-align: center;
      }

      /* Hide mobile-only items on desktop */
      .mobile-only {
        display: none;
      }

      .nav-links a:hover,
      .nav-links a.active {
        color: #7c3aed;
      }

      .nav-links a.active {
        font-weight: bold;
      }

      .nav-btn {
        background: linear-gradient(135deg, #7c3aed 0%, #a855f7 100%);
        color: white;
        border: none;
        padding: 0.7rem 1.5rem;
        border-radius: 8px;
        cursor: pointer;
        font-weight: 600;
        transition: transform 0.3s;
      }

      /* Hide start button on mobile by default */
      #start-btn,
      #logout-btn {
        display: none;
      }

      .nav-btn:hover {
        transform: translateY(-2px);
      }

      .container {
        margin-top: 5rem;
        padding: 1rem 5%;
        position: relative;
        z-index: 1;
        display: grid;
        grid-template-columns: 1fr 1fr;
        gap: 2rem;
        min-height: calc(100vh - 5rem);
        padding-bottom: 1rem;
      }

      .left-panel {
        overflow-y: auto;
        max-height: calc(100vh - 7rem);
        padding-left: 1rem;
      }

      .left-panel::-webkit-scrollbar {
        width: 8px;
      }

      .left-panel::-webkit-scrollbar-track {
        background: rgba(15, 23, 42, 0.3);
        border-radius: 4px;
      }

      .left-panel::-webkit-scrollbar-thumb {
        background: rgba(124, 58, 237, 0.5);
        border-radius: 4px;
      }

      .breadcrumb {
        display: flex;
        align-items: center;
        gap: 0.5rem;
        margin-bottom: 1.5rem;
        font-size: 0.9rem;
        color: #94a3b8;
      }

      .breadcrumb a {
        color: #94a3b8;
        text-decoration: none;
        transition: color 0.3s;
      }

      .breadcrumb a:hover,
      .report-link:hover {
        color: #7c3aed !important;
      }

      .problem-header {
        margin-bottom: 2rem;
      }

      .problem-title {
        font-size: 2rem;
        margin-bottom: 1rem;
        color: #fff;
      }

      .problem-meta {
        display: flex;
        gap: 1rem;
        align-items: center;
        flex-wrap: wrap;
      }

      .difficulty {
        padding: 0.4rem 0.8rem;
        border-radius: 6px;
        font-size: 0.85rem;
        font-weight: 600;
      }

      .difficulty.easy {
        background: rgba(34, 197, 94, 0.2);
        color: #22c55e;
      }

      .difficulty.medium {
        background: rgba(234, 179, 8, 0.2);
        color: #eab308;
      }

      .difficulty.hard {
        background: rgba(239, 68, 68, 0.2);
        color: #ef4444;
      }

      .tag {
        padding: 0.3rem 0.6rem;
        border-radius: 6px;
        font-size: 0.75rem;
        font-weight: 600;
        background: rgba(124, 58, 237, 0.2);
        color: #a855f7;
      }

      .acceptance {
        color: #94a3b8;
        font-size: 0.9rem;
      }

      .content-section {
        background: rgba(15, 23, 42, 0.6);
        border: 1px solid rgba(124, 58, 237, 0.2);
        border-radius: 12px;
        padding: 1.5rem;
        margin-bottom: 1.5rem;
        backdrop-filter: blur(10px);
      }

      .section-title {
        font-size: 1.1rem;
        font-weight: 600;
        margin-bottom: 1rem;
        color: #a855f7;
      }

      .problem-description {
        line-height: 1.8;
        color: #cbd5e1;
        margin-bottom: 1rem;
      }

      .example {
        background: rgba(124, 58, 237, 0.1);
        border-right: 3px solid #7c3aed;
        padding: 1rem;
        margin: 1rem 0;
        border-radius: 6px;
      }

      .example-title {
        font-weight: 600;
        color: #a855f7;
        margin-bottom: 0.5rem;
      }

      .code-block {
        background: rgba(0, 0, 0, 0.3);
        padding: 1rem;
        border-radius: 6px;
        font-family: "JetBrains Mono", monospace;
        font-size: 0.9rem;
        color: #e2e8f0;
        margin: 0.5rem 0;
        overflow-x: auto;
        direction: ltr;
        text-align: left;
      }

      .constraints {
        list-style: none;
        padding-right: 0;
      }

      .constraints li {
        padding: 0.5rem 0;
        padding-right: 1.5rem;
        position: relative;
        color: #cbd5e1;
      }

      .constraints li::before {
        content: "◂";
        position: absolute;
        right: 0;
        color: #7c3aed;
      }

      .right-panel {
        display: flex;
        flex-direction: column;
        gap: 1rem;
      }

      .editor-container {
        background: rgba(15, 23, 42, 0.6);
        border: 1px solid rgba(124, 58, 237, 0.2);
        border-radius: 12px;
        overflow: hidden;
        backdrop-filter: blur(10px);
        display: flex;
        flex-direction: column;
        flex: 1;
        direction: ltr;
      }

      .editor-header {
        display: flex;
        justify-content: space-between;
        align-items: center;
        padding: 1rem 1.5rem;
        background: rgba(124, 58, 237, 0.1);
        border-bottom: 1px solid rgba(124, 58, 237, 0.2);
      }

      .language-selector {
        background: rgba(0, 0, 0, 0.3);
        border: 1px solid rgba(124, 58, 237, 0.3);
        color: white;
        padding: 0.5rem 1rem;
        border-radius: 6px;
        cursor: pointer;
        font-family: "Cairo", sans-serif;
        font-size: 0.85rem;
      }

      .editor-actions {
        display: flex;
        gap: 0.5rem;
      }

      .action-btn {
        background: rgba(124, 58, 237, 0.2);
        border: 1px solid rgba(124, 58, 237, 0.3);
        color: #a855f7;
        padding: 0.5rem 1rem;
        border-radius: 6px;
        cursor: pointer;
        font-weight: 600;
        font-size: 0.85rem;
        transition: all 0.3s;
      }

      .action-btn:hover {
        background: rgba(124, 58, 237, 0.3);
      }

      .code-editor {
        flex: 1 1 auto;
        position: relative;
        background: rgba(0, 0, 0, 0.3);
        direction: ltr;
        text-align: left;
        height: 360px;
        overflow: hidden;
        transition: height 0.3s ease;
      }

      .code-editor.collapsed {
        height: 200px;
        /*flex: 0 0 200px;*/
      }

      .code-editor .monaco-editor,
      .code-editor .monaco-editor-background,
      .code-editor .margin,
      .code-editor .monaco-scrollable-element {
        background-color: hsl(220 25% 8% / 1) !important;
      }

      .submit-section {
        display: flex;
        gap: 1rem;
        padding: 1rem 1.5rem;
        background: rgba(124, 58, 237, 0.05);
        border-top: 1px solid rgba(124, 58, 237, 0.2);
      }

      .run-btn {
        background: rgba(124, 58, 237, 0.2);
        border: 1px solid rgba(124, 58, 237, 0.3);
        color: #a855f7;
        padding: 0.7rem 1.5rem;
        border-radius: 6px;
        cursor: pointer;
        font-weight: 600;
        transition: all 0.3s;
      }

      .run-btn:hover {
        background: rgba(124, 58, 237, 0.3);
      }

      .submit-btn {
        background: linear-gradient(135deg, #7c3aed 0%, #a855f7 100%);
        color: white;
        border: none;
        padding: 0.7rem 2rem;
        border-radius: 6px;
        cursor: pointer;
        font-weight: 600;
        transition: transform 0.3s;
        flex: 1;
      }

      .submit-btn:hover {
        transform: translateY(-2px);
      }

      .test-results {
        background: rgba(15, 23, 42, 0.6);
        border: 1px solid rgba(124, 58, 237, 0.2);
        border-radius: 12px;
        padding: 1.5rem;
        backdrop-filter: blur(10px);
        max-height: 200px;
        overflow-y: auto;
      }

      .test-results::-webkit-scrollbar {
        width: 8px;
      }

      .test-results::-webkit-scrollbar-track {
        background: rgba(15, 23, 42, 0.3);
        border-radius: 4px;
      }

      .test-results::-webkit-scrollbar-thumb {
        background: rgba(124, 58, 237, 0.5);
        border-radius: 4px;
      }

      .result-header {
        font-weight: 600;
        margin-bottom: 1rem;
        color: #a855f7;
      }

      .test-case {
        padding: 0.8rem;
        background: rgba(124, 58, 237, 0.1);
        border-radius: 6px;
        margin-bottom: 0.5rem;
        font-family: "JetBrains Mono", monospace;
        font-size: 0.85rem;
      }

      .test-case.passed {
        border-right: 3px solid #22c55e;
      }

      .test-case.failed {
        border-right: 3px solid #ef4444;
      }

      @media (max-width: 1024px) {
        .container {
          grid-template-columns: 1fr;
        }

        .left-panel {
          max-height: none;
          margin-bottom: 2rem;
        }
      }

      /* Show start button on desktop */
      @media (min-width: 769px) {
        #start-btn {
          display: inline-block;
        }
      }

      @media (max-width: 768px) {
        .mobile-menu-btn {
          display: block;
        }

        /* Hide start button on mobile */
        #start-btn {
          display: none;
        }

        .mobile-only {
          display: block;
          margin-top: 1rem;
          padding-top: 1rem;
          border-top: 1px solid rgba(255, 255, 255, 0.1);
        }

        .mobile-only a {
          display: flex !important;
          align-items: center;
          gap: 10px;
          padding: 0.8rem 0;
        }

        .nav-links {
          position: fixed;
          top: 0;
          left: -100%;
          height: 100vh;
          width: 70%;
          max-width: 300px;
          background: rgba(10, 14, 39, 0.98);
          backdrop-filter: blur(20px);
          flex-direction: column;
          padding: 5rem 2rem 2rem;
          gap: 1.5rem;
          transition: left 0.3s ease;
          border-right: 1px solid rgba(124, 58, 237, 0.2);
          z-index: 999;
          margin: 0;
        }

        .nav-links.active {
          left: 0;
        }

        .nav-links a {
          font-size: 1.2rem;
          padding: 0.5rem 0;
          border-bottom: 1px solid rgba(255, 255, 255, 0.1);
          display: block;
        }

        .problem-title {
          font-size: 1.5rem;
        }

        .logo img {
          height: 32px;
          max-width: 120px;
        }

        .container {
          padding: 1rem 3%;
        }

        .editor-header {
          flex-direction: column;
          gap: 1rem;
          align-items: stretch;
        }

        .submit-section {
          flex-direction: column;
        }
      }