* {
            margin: 0;
            padding: 0;
            box-sizing: border-box;
            -webkit-tap-highlight-color: transparent;
        }

        /* CHANGED GRADIENT COLOR for MS Excel (Teal/Aqua) */
        body {
            font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
            background: linear-gradient(135deg, #0c4841 0%, #29a095 100%); /* Teal/Aqua */
            background-attachment: fixed;
            min-height: 100vh;
            color: #333;
            -webkit-font-smoothing: antialiased;
            -moz-osx-font-smoothing: grayscale;
        }

        .container {
            max-width: 1200px;
            margin: 0 auto;
            padding: 0 20px;
        }

        /* Header Styles */
        header {
            background: rgba(255, 255, 255, 0.95);
            -webkit-backdrop-filter: blur(10px);
            backdrop-filter: blur(10px);
            box-shadow: 0 4px 20px rgba(0, 0, 0, 0.1);
            position: -webkit-sticky;
            position: sticky;
            top: 0;
            z-index: 1000;
            -webkit-transition: all 0.3s ease;
            -moz-transition: all 0.3s ease;
            -o-transition: all 0.3s ease;
            transition: all 0.3s ease;
        }

        nav {
            display: -webkit-box;
            display: -ms-flexbox;
            display: flex;
            -webkit-box-pack: justify;
            -ms-flex-pack: justify;
            justify-content: space-between;
            -webkit-box-align: center;
            -ms-flex-align: center;
            align-items: center;
            padding: 1rem 0;
        }
        
         /* Footer */
        footer {
            background: rgba(0, 0, 0, 0.8);
            color: white;
            text-align: center;
            padding: 2rem 0;
            margin-top: 4rem;
        }


        .logo {
            display: -webkit-box;
            display: -ms-flexbox;
            display: flex;
            -webkit-box-align: center;
            -ms-flex-align: center;
            align-items: center;
            font-size: 1.8rem;
            font-weight: bold;
            color: #29a095; /* Matched to new theme color */
            text-decoration: none;
            -webkit-transition: -webkit-transform 0.3s ease;
            transition: -webkit-transform 0.3s ease;
            -o-transition: transform 0.3s ease;
            -moz-transition: transform 0.3s ease, -moz-transform 0.3s ease;
            transition: transform 0.3s ease;
            transition: transform 0.3s ease, -webkit-transform 0.3s ease, -moz-transform 0.3s ease;
        }

        .logo:hover {
            -webkit-transform: scale(1.05);
            -moz-transform: scale(1.05);
            -ms-transform: scale(1.05);
            -o-transform: scale(1.05);
            transform: scale(1.05);
        }

        .logo-icon {
            width: 40px;
            height: 40px;
            background: linear-gradient(45deg, #1f786d, #29a095); /* Matched to new theme color */
            border-radius: 50%;
            margin-right: 10px;
            display: -webkit-box;
            display: -ms-flexbox;
            display: flex;
            -webkit-box-align: center;
            -ms-flex-align: center;
            align-items: center;
            -webkit-box-pack: center;
            -ms-flex-pack: center;
            justify-content: center;
            color: white;
            font-weight: bold;
            -webkit-animation: pulse 2s infinite;
            -moz-animation: pulse 2s infinite;
            -o-animation: pulse 2s infinite;
            animation: pulse 2s infinite;
        }

        @-webkit-keyframes pulse {
            0%, 100% { -webkit-transform: scale(1); transform: scale(1); }
            50% { -webkit-transform: scale(1.1); transform: scale(1.1); }
        }

        @-moz-keyframes pulse {
            0%, 100% { -moz-transform: scale(1); transform: scale(1); }
            50% { -moz-transform: scale(1.1); transform: scale(1.1); }
        }

        @-o-keyframes pulse {
            0%, 100% { -o-transform: scale(1); transform: scale(1); }
            50% { -o-transform: scale(1.1); transform: scale(1.1); }
        }

        @keyframes pulse {
            0%, 100% { 
                -webkit-transform: scale(1);
                -moz-transform: scale(1);
                -ms-transform: scale(1);
                -o-transform: scale(1);
                transform: scale(1); 
            }
            50% { 
                -webkit-transform: scale(1.1);
                -moz-transform: scale(1.1);
                -ms-transform: scale(1.1);
                -o-transform: scale(1.1);
                transform: scale(1.1); 
            }
        }

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

        .nav-links a {
            text-decoration: none;
            color: #333;
            font-weight: 500;
            -webkit-transition: color 0.3s ease;
            -moz-transition: color 0.3s ease;
            -o-transition: color 0.3s ease;
            transition: color 0.3s ease;
            position: relative;
        }

        .nav-links a:hover {
            color: #29a095; /* Matched to new theme color */
        }

        .nav-links a::after {
            content: '';
            position: absolute;
            width: 0;
            height: 2px;
            bottom: -5px;
            left: 0;
            background: #29a095; /* Matched to new theme color */
            -webkit-transition: width 0.3s ease;
            -moz-transition: width 0.3s ease;
            -o-transition: width 0.3s ease;
            transition: width 0.3s ease;
        }

        .nav-links a:hover::after {
            width: 100%;
        }

        .mobile-menu-btn {
            display: none;
            -webkit-box-orient: vertical;
            -webkit-box-direction: normal;
            -ms-flex-direction: column;
            flex-direction: column;
            cursor: pointer;
            padding: 5px;
        }

        .mobile-menu-btn span {
            width: 25px;
            height: 3px;
            background: #333;
            margin: 3px 0;
            -webkit-transition: 0.3s;
            -moz-transition: 0.3s;
            -o-transition: 0.3s;
            transition: 0.3s;
        }

        .quiz-container {
            max-width: 900px;
            margin: 2rem auto;
            background: rgba(255, 255, 255, 0.95);
            -webkit-backdrop-filter: blur(10px);
            backdrop-filter: blur(10px);
            border-radius: 20px;
            box-shadow: 0 20px 40px rgba(0, 0, 0, 0.1);
            overflow: hidden;
        }

        .quiz-header {
            background: linear-gradient(45deg, #078c7c, #29a095); /* Matched to new theme color */
            color: white;
            padding: 2rem;
            text-align: center;
        }

        .quiz-title {
            font-size: 2.5rem;
            margin-bottom: 0.5rem;
            display: -webkit-box;
            display: -ms-flexbox;
            display: flex;
            -webkit-box-align: center;
            -ms-flex-align: center;
            align-items: center;
            -webkit-box-pack: center;
            -ms-flex-pack: center;
            justify-content: center;
            gap: 1rem;
        }

        .quiz-icon {
            width: 60px;
            height: 60px;
            background: rgba(255, 255, 255, 0.2);
            border-radius: 50%;
            display: -webkit-box;
            display: -ms-flexbox;
            display: flex;
            -webkit-box-align: center;
            -ms-flex-align: center;
            align-items: center;
            -webkit-box-pack: center;
            -ms-flex-pack: center;
            justify-content: center;
            font-size: 2rem;
        }

        .level-selection {
            padding: 3rem 2rem;
            text-align: center;
        }

        .initial-name-section {
            margin-bottom: 2rem;
        }

        .initial-name-section h2 {
            font-size: 2rem;
            margin-bottom: 1rem;
            color: #333;
        }

        .level-selection h2 {
            font-size: 2rem;
            margin-bottom: 2rem;
            color: #333;
        }

        .level-buttons {
            display: grid;
            grid-template-columns: repeat(4, 1fr);
            gap: 1rem;
            margin-bottom: 2rem;
        }

        .level-btn {
            background: linear-gradient(45deg, #1f786d, #29a095); /* Matched to new theme color */
            color: white;
            border: none;
            padding: 1.5rem 1rem;
            border-radius: 15px;
            font-size: 1rem;
            font-weight: bold;
            cursor: pointer;
            -webkit-transition: all 0.3s ease;
            -moz-transition: all 0.3s ease;
            -o-transition: all 0.3s ease;
            transition: all 0.3s ease;
            box-shadow: 0 8px 20px rgba(33, 150, 243, 0.3); /* Adjusted shadow color */
            min-height: 120px;
            display: -webkit-box;
            display: -ms-flexbox;
            display: flex;
            -webkit-box-orient: vertical;
            -webkit-box-direction: normal;
            -ms-flex-direction: column;
            flex-direction: column;
            -webkit-box-pack: center;
            -ms-flex-pack: center;
            justify-content: center;
            -webkit-box-align: center;
            -ms-flex-align: center;
            align-items: center;
            text-align: center;
            -webkit-appearance: none;
            -moz-appearance: none;
            appearance: none;
        }

        .level-btn h3 {
            margin-bottom: 0.5rem;
            font-size: 1.1rem;
        }

        .level-btn p {
            font-size: 0.85rem;
            opacity: 0.9;
            line-height: 1.3;
        }

        .level-btn:active {
            -webkit-transform: translateY(-3px);
            -moz-transform: translateY(-3px);
            -ms-transform: translateY(-3px);
            -o-transform: translateY(-3px);
            transform: translateY(-3px);
            box-shadow: 0 12px 25px rgba(33, 150, 243, 0.4); /* Adjusted shadow color */
        }

        .level-btn.selected {
            background: linear-gradient(45deg, #2e7d32, #4caf50);
        }

        .start-quiz-btn {
            background: linear-gradient(45deg, #ff6b6b, #ffa500);
            color: white;
            border: none;
            padding: 1rem 2rem;
            border-radius: 25px;
            font-size: 1.2rem;
            font-weight: bold;
            cursor: pointer;
            -webkit-transition: all 0.3s ease;
            -moz-transition: all 0.3s ease;
            -o-transition: all 0.3s ease;
            transition: all 0.3s ease;
            margin-top: 1rem;
            -webkit-appearance: none;
            -moz-appearance: none;
            appearance: none;
        }

        .start-quiz-btn:active {
            -webkit-transform: scale(1.03);
            -moz-transform: scale(1.03);
            -ms-transform: scale(1.03);
            -o-transform: scale(1.03);
            transform: scale(1.03);
        }

        .start-quiz-btn:disabled {
            opacity: 0.5;
            cursor: not-allowed;
        }

        .quiz-content {
            display: none;
            padding: 2rem;
        }

        .quiz-progress {
            margin-bottom: 2rem;
        }

        .progress-bar {
            width: 100%;
            height: 8px;
            background: #e0e0e0;
            border-radius: 4px;
            overflow: hidden;
            margin-bottom: 1rem;
        }

        .progress-fill {
            height: 100%;
            background: linear-gradient(45deg, #1f786d, #29a095); /* Matched to new theme color */
            -webkit-transition: width 0.3s ease;
            -moz-transition: width 0.3s ease;
            -o-transition: width 0.3s ease;
            transition: width 0.3s ease;
        }

        .quiz-info {
            display: -webkit-box;
            display: -ms-flexbox;
            display: flex;
            -webkit-box-pack: justify;
            -ms-flex-pack: justify;
            justify-content: space-between;
            -webkit-box-align: center;
            -ms-flex-align: center;
            align-items: center;
            margin-bottom: 2rem;
            font-weight: bold;
        }

        .question-nav {
            display: -webkit-box;
            display: -ms-flexbox;
            display: flex;
            -ms-flex-wrap: wrap;
            flex-wrap: wrap;
            gap: 0.5rem;
            margin-bottom: 2rem;
        }

        .question-num {
            width: 40px;
            height: 40px;
            border: 2px solid #29a095; /* Matched to new theme color */
            border-radius: 50%;
            display: -webkit-box;
            display: -ms-flexbox;
            display: flex;
            -webkit-box-align: center;
            -ms-flex-align: center;
            align-items: center;
            -webkit-box-pack: center;
            -ms-flex-pack: center;
            justify-content: center;
            cursor: pointer;
            -webkit-transition: all 0.3s ease;
            -moz-transition: all 0.3s ease;
            -o-transition: all 0.3s ease;
            transition: all 0.3s ease;
            font-weight: bold;
            background: white;
            color: #29a095; /* Matched to new theme color */
        }

        .question-num.current {
            background: #29a095; /* Matched to new theme color */
            color: white;
        }

        .question-num.answered {
            background: #4caf50;
            border-color: #4caf50;
            color: white;
        }

        .question-container {
            background: #f8f9fa;
            padding: 1.2rem;
            border-radius: 15px;
            margin-bottom: 1.2rem;
        }

        .question-text {
            font-size: 1.3rem;
            margin-bottom: 1rem;
            line-height: 1.4;
            color: #333;
        }

        .options {
            display: grid;
            gap: 1rem;
        }

        .option {
            background: white;
            border: 2px solid #e0e0e0;
            padding: 1rem 1.5rem;
            border-radius: 10px;
            cursor: pointer;
            -webkit-transition: all 0.3s ease;
            -moz-transition: all 0.3s ease;
            -o-transition: all 0.3s ease;
            transition: all 0.3s ease;
            font-size: 1.1rem;
        }

        .option:active {
            border-color: #29a095; /* Matched to new theme color */
            -webkit-transform: translateX(3px);
            -moz-transform: translateX(3px);
            -ms-transform: translateX(3px);
            -o-transform: translateX(3px);
            transform: translateX(3px);
        }

        .option.selected {
            border-color: #29a095; /* Matched to new theme color */
            background: rgba(41, 160, 149, 0.1); /* Adjusted rgba for new theme color */
        }

        .quiz-controls {
            display: -webkit-box;
            display: -ms-flexbox;
            display: flex;
            -webkit-box-pack: justify;
            -ms-flex-pack: justify;
            justify-content: space-between;
            -webkit-box-align: center;
            -ms-flex-align: center;
            align-items: center;
            gap: 1rem;
        }

        .control-btn {
            background: linear-gradient(45deg, #1f786d, #29a095); /* Matched to new theme color */
            color: white;
            border: none;
            padding: 0.8rem 2rem;
            border-radius: 25px;
            font-weight: bold;
            cursor: pointer;
            -webkit-transition: all 0.3s ease;
            -moz-transition: all 0.3s ease;
            -o-transition: all 0.3s ease;
            transition: all 0.3s ease;
            -webkit-appearance: none;
            -moz-appearance: none;
            appearance: none;
        }

        .control-btn:active {
            -webkit-transform: scale(1.03);
            -moz-transform: scale(1.03);
            -ms-transform: scale(1.03);
            -o-transform: scale(1.03);
            transform: scale(1.03);
        }

        .control-btn:disabled {
            opacity: 0.5;
            cursor: not-allowed;
        }

        .submit-btn {
            background: linear-gradient(45deg, #ff6b6b, #ffa500);
        }

        .results-container {
            display: none;
            padding: 3rem 2rem;
            text-align: center;
        }

        .congratulations {
            font-size: 2rem;
            color: #4caf50;
            margin-bottom: 1rem;
            font-weight: bold;
        }

        .score-display {
            font-size: 3rem;
            font-weight: bold;
            margin: 2rem 0;
            color: #29a095; /* Matched to new theme color */
        }

        .results-details {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
            gap: 2rem;
            margin: 2rem 0;
        }

        .result-item {
            background: rgba(255, 255, 255, 0.8);
            padding: 1.5rem;
            border-radius: 15px;
            box-shadow: 0 8px 20px rgba(0, 0, 0, 0.1);
        }

        .result-item h3 {
            font-size: 2rem;
            margin-bottom: 0.5rem;
        }

        .correct { color: #4caf50; }
        .incorrect { color: #f44336; }

        .next-level-btn {
            background: linear-gradient(45deg, #4caf50, #8bc34a);
            color: white;
            border: none;
            padding: 1rem 2rem;
            border-radius: 25px;
            font-size: 1.2rem;
            font-weight: bold;
            cursor: pointer;
            -webkit-transition: all 0.3s ease;
            -moz-transition: all 0.3s ease;
            -o-transition: all 0.3s ease;
            transition: all 0.3s ease;
            margin: 1rem;
            -webkit-appearance: none;
            -moz-appearance: none;
            appearance: none;
        }

        .next-level-btn:active {
            -webkit-transform: scale(1.03);
            -moz-transform: scale(1.03);
            -ms-transform: scale(1.03);
            -o-transform: scale(1.03);
            transform: scale(1.03);
        }

        .answer-review-section {
            margin-top: 2rem;
            text-align: left;
        }

        .answer-item {
            background: white;
            border-radius: 12px;
            padding: 1.5rem;
            margin-bottom: 1rem;
            box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
            border-left: 5px solid #e0e0e0;
        }

        .answer-item.correct {
            border-left-color: #4caf50;
            background: rgba(76, 175, 80, 0.05);
        }

        .answer-item.incorrect {
            border-left-color: #f44336;
            background: rgba(244, 67, 54, 0.05);
        }

        .answer-item.unanswered {
            border-left-color: #ff9800;
            background: rgba(255, 152, 0, 0.05);
        }

        .answer-question {
            font-weight: bold;
            font-size: 1.1rem;
            margin-bottom: 1rem;
            color: #333;
            display: -webkit-box;
            display: -ms-flexbox;
            display: flex;
            -webkit-box-align: center;
            -ms-flex-align: center;
            align-items: center;
            gap: 0.5rem;
        }

        .answer-status {
            width: 24px;
            height: 24px;
            border-radius: 50%;
            display: -webkit-box;
            display: -ms-flexbox;
            display: flex;
            -webkit-box-align: center;
            -ms-flex-align: center;
            align-items: center;
            -webkit-box-pack: center;
            -ms-flex-pack: center;
            justify-content: center;
            font-weight: bold;
            font-size: 0.8rem;
            color: white;
        }

        .answer-status.correct {
            background: #4caf50;
        }

        .answer-status.incorrect {
            background: #f44336;
        }

        .answer-status.unanswered {
            background: #ff9800;
        }

        .answer-details {
            display: grid;
            gap: 0.5rem;
        }

        .answer-row {
            padding: 0.5rem;
            border-radius: 6px;
            font-size: 0.95rem;
        }

        .user-answer {
            border: 1px solid #29a095; /* Matched to new theme color */
            background: rgba(41, 160, 149, 0.1); /* Adjusted rgba for new theme color */
        }

        .correct-answer {
            background: rgba(76, 175, 80, 0.1);
            border: 1px solid #4caf50;
        }

        .wrong-user-answer {
            background: rgba(244, 67, 54, 0.1);
            border: 1px solid #f44336;
        }

        .answer-label {
            font-weight: bold;
            margin-right: 0.5rem;
        }

        .name-input {
            width: 100%;
            max-width: 350px;
            padding: 0.8rem 1rem;
            font-size: 1rem;
            border: 2px solid #29a095; /* Matched to new theme color */
            border-radius: 12px;
            outline: none;
            -webkit-transition: all 0.3s ease;
            -moz-transition: all 0.3s ease;
            -o-transition: all 0.3s ease;
            transition: all 0.3s ease;
            background: #fff;
            box-shadow: 0 4px 10px rgba(0, 0, 0, 0.05);
            margin-top: 1rem;
            -webkit-appearance: none;
            -moz-appearance: none;
            appearance: none;
        }

        .name-input:focus {
            border-color: #1f786d; /* Matched to new theme color */
            box-shadow: 0 6px 15px rgba(41, 160, 149, 0.3); /* Adjusted shadow color */
        }

        @-webkit-keyframes shake {
            0%, 100% { -webkit-transform: translateX(0); transform: translateX(0); }
            25% { -webkit-transform: translateX(-10px); transform: translateX(-10px); }
            75% { -webkit-transform: translateX(10px); transform: translateX(10px); }
        }

        @keyframes shake {
            0%, 100% { 
                -webkit-transform: translateX(0);
                -moz-transform: translateX(0);
                -ms-transform: translateX(0);
                -o-transform: translateX(0);
                transform: translateX(0); 
            }
            25% { 
                -webkit-transform: translateX(-10px);
                -moz-transform: translateX(-10px);
                -ms-transform: translateX(-10px);
                -o-transform: translateX(-10px);
                transform: translateX(-10px); 
            }
            75% { 
                -webkit-transform: translateX(10px);
                -moz-transform: translateX(10px);
                -ms-transform: translateX(10px);
                -o-transform: translateX(10px);
                transform: translateX(10px); 
            }
        }

        @media (max-width: 1200px) {
            .level-buttons {
                gap: 0.8rem;
            }
            
            .level-btn {
                padding: 1.2rem 0.8rem;
                min-height: 110px;
            }
            
            .level-btn h3 {
                font-size: 1rem;
            }
            
            .level-btn p {
                font-size: 0.8rem;
            }
        }

        @media (max-width: 768px) {
            .nav-links {
                position: fixed;
                top: 70px;
                left: -100%;
                width: 100%;
                height: calc(100vh - 70px);
                background: rgba(255, 255, 255, 0.95);
                -webkit-backdrop-filter: blur(10px);
                backdrop-filter: blur(10px);
                -webkit-box-orient: vertical;
                -webkit-box-direction: normal;
                -ms-flex-direction: column;
                flex-direction: column;
                -webkit-box-pack: center;
                -ms-flex-pack: center;
                justify-content: center;
                -webkit-box-align: center;
                -ms-flex-align: center;
                align-items: center;
                -webkit-transition: left 0.3s ease;
                -moz-transition: left 0.3s ease;
                -o-transition: left 0.3s ease;
                transition: left 0.3s ease;
            }

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

            .mobile-menu-btn {
                display: -webkit-box;
                display: -ms-flexbox;
                display: flex;
            }

            .quiz-title {
                font-size: 2rem;
                -webkit-box-orient: vertical;
                -webkit-box-direction: normal;
                -ms-flex-direction: column;
                flex-direction: column;
                gap: 0.5rem;
            }

            .level-buttons {
                grid-template-columns: repeat(2, 1fr);
                gap: 1rem;
            }

            .quiz-info {
                -webkit-box-orient: vertical;
                -webkit-box-direction: normal;
                -ms-flex-direction: column;
                flex-direction: column;
                gap: 1rem;
            }

            .quiz-controls {
                -webkit-box-orient: vertical;
                -webkit-box-direction: normal;
                -ms-flex-direction: column;
                flex-direction: column;
                gap: 1rem;
            }

            .control-btn {
                width: 100%;
            }

            .results-details {
                grid-template-columns: 1fr;
            }
        }

        @media (max-width: 480px) {
            .container, .quiz-container {
                padding: 0 10px;
                margin: 1rem auto;
            }

            .quiz-header {
                padding: 1.5rem;
            }

            .level-selection, .quiz-content, .results-container {
                padding: 2rem 1rem;
            }

            .question-nav {
                -webkit-box-pack: center;
                -ms-flex-pack: center;
                justify-content: center;
            }

            .question-num {
                width: 35px;
                height: 35px;
                font-size: 0.9rem;
            }

            .question-text {
                margin-bottom: 0.8rem;
                font-size: 1.1rem;
            }

            .question-container {
                padding: 1rem;
                margin-bottom: 1rem;
            }
        }