:root {
            --primary-color: #4a6fff;
            --secondary-color: #8a2be2;
            --accent-color: #00e5ff;
            --text-color: #ffffff;
            --bg-color: #0a0a1a;
            --card-bg: rgba(16, 18, 40, 0.8);
            --border-color: rgba(74, 111, 255, 0.3);
            --glow-color: rgba(74, 111, 255, 0.5);
        }

        [data-theme="light"] {
            --primary-color: #4a6fff;
            --secondary-color: #8a2be2;
            --accent-color: #0066cc;
            --text-color: #1a1a2e;
            --bg-color: #f0f2ff;
            --card-bg: rgba(255, 255, 255, 0.9);
            --border-color: rgba(74, 111, 255, 0.2);
            --glow-color: rgba(74, 111, 255, 0.3);
        }

        * {
            margin: 0;
            padding: 0;
            box-sizing: border-box;
            transition: background-color 0.3s, color 0.3s, border-color 0.3s;
        }

        body {
            font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
            background-color: var(--bg-color);
            color: var(--text-color);
            line-height: 1.6;
            overflow-x: hidden;
            position: relative;
        }

        /* Background Space Animation */
        .space-background {
            position: fixed;
            top: 0;
            left: 0;
            width: 100%;
            height: 100%;
            z-index: -1;
            background: linear-gradient(to bottom, #000428, #004e92);
        }

        .stars {
            position: absolute;
            top: 0;
            left: 0;
            width: 100%;
            height: 100%;
            background-image: 
                radial-gradient(2px 2px at 20px 30px, #eee, transparent),
                radial-gradient(2px 2px at 40px 70px, #fff, transparent),
                radial-gradient(1px 1px at 90px 40px, #fff, transparent),
                radial-gradient(1px 1px at 130px 80px, #fff, transparent),
                radial-gradient(2px 2px at 160px 30px, #ddd, transparent);
            background-repeat: repeat;
            background-size: 200px 100px;
            animation: starsMove 50s linear infinite;
        }

        .stars:nth-child(2) {
            background-image: 
                radial-gradient(2px 2px at 10px 10px, #eee, transparent),
                radial-gradient(2px 2px at 60px 90px, #fff, transparent),
                radial-gradient(1px 1px at 110px 20px, #fff, transparent),
                radial-gradient(1px 1px at 150px 60px, #fff, transparent),
                radial-gradient(2px 2px at 180px 10px, #ddd, transparent);
            animation-duration: 80s;
            opacity: 0.7;
        }

        .nebula {
            position: absolute;
            width: 100%;
            height: 100%;
            background: 
                radial-gradient(circle at 20% 30%, rgba(74, 111, 255, 0.2) 0%, transparent 40%),
                radial-gradient(circle at 80% 70%, rgba(138, 43, 226, 0.2) 0%, transparent 40%),
                radial-gradient(circle at 40% 80%, rgba(0, 229, 255, 0.15) 0%, transparent 40%);
            animation: nebulaPulse 20s ease-in-out infinite alternate;
        }

        @keyframes starsMove {
            from { transform: translateY(0); }
            to { transform: translateY(-100px); }
        }

        @keyframes nebulaPulse {
            from { opacity: 0.5; transform: scale(1); }
            to { opacity: 0.8; transform: scale(1.1); }
        }

        .container {
            max-width: 1200px;
            margin: 0 auto;
            padding: 0 20px;
            position: relative;
            z-index: 1;
        }

        /* Header Styles */
        header {
            display: flex;
            justify-content: space-between;
            align-items: center;
            padding: 20px 0;
            position: sticky;
            top: 0;
            background-color: rgba(10, 10, 26, 0.8);
            backdrop-filter: blur(10px);
            z-index: 100;
            border-bottom: 1px solid var(--border-color);
        }

        .logo {
            display: flex;
            align-items: center;
        }

        .logo h1 {
            color: var(--accent-color);
            font-size: 1.8rem;
            text-shadow: 0 0 10px var(--glow-color);
            background: linear-gradient(45deg, var(--accent-color), var(--primary-color));
            -webkit-background-clip: text;
            -webkit-text-fill-color: transparent;
        }

        nav ul {
            display: flex;
            list-style: none;
        }

        nav ul li {
            margin-left: 30px;
        }

        nav ul li a {
            text-decoration: none;
            color: var(--text-color);
            font-weight: 500;
            position: relative;
            padding: 5px 0;
        }

        nav ul li a:hover {
            color: var(--accent-color);
        }

        nav ul li a::after {
            content: '';
            position: absolute;
            width: 0;
            height: 2px;
            bottom: 0;
            left: 0;
            background: linear-gradient(90deg, var(--accent-color), var(--primary-color));
            transition: width 0.3s;
        }

        nav ul li a:hover::after {
            width: 100%;
        }

        .theme-toggle button {
            background: none;
            border: none;
            color: var(--text-color);
            font-size: 1.2rem;
            cursor: pointer;
            padding: 8px;
            border-radius: 50%;
            background-color: var(--card-bg);
            border: 1px solid var(--border-color);
            box-shadow: 0 0 10px var(--glow-color);
        }

        .theme-toggle button:hover {
            background-color: var(--accent-color);
            color: white;
            box-shadow: 0 0 15px var(--accent-color);
        }

        /* Section Styles */
        .section {
            padding: 100px 0;
        }

        .section-title {
            text-align: center;
            margin-bottom: 60px;
            color: var(--accent-color);
            font-size: 2.5rem;
            position: relative;
            text-shadow: 0 0 10px var(--glow-color);
        }

        .section-title::after {
            content: '';
            position: absolute;
            width: 100px;
            height: 4px;
            background: linear-gradient(90deg, var(--accent-color), var(--primary-color));
            bottom: -15px;
            left: 50%;
            transform: translateX(-50%);
            border-radius: 2px;
            box-shadow: 0 0 10px var(--glow-color);
        }

        /* Profile Section */
        .profile-container {
            display: flex;
            align-items: center;
            gap: 50px;
        }

        .profile-image {
            flex: 0 0 300px;
            position: relative;
        }

        .profile-image::before {
            content: '';
            position: absolute;
            width: 100%;
            height: 100%;
            border-radius: 50%;
            background: linear-gradient(45deg, var(--accent-color), var(--primary-color), var(--secondary-color));
            top: -5px;
            left: -5px;
            z-index: -1;
            filter: blur(10px);
            opacity: 0.7;
            animation: rotate 10s linear infinite;
        }

        .profile-image img {
            width: 100%;
            border-radius: 50%;
            border: 5px solid transparent;
            background: linear-gradient(45deg, var(--accent-color), var(--primary-color), var(--secondary-color)) border-box;
            -webkit-mask: linear-gradient(#fff 0 0) padding-box, linear-gradient(#fff 0 0);
            -webkit-mask-composite: xor;
            mask-composite: exclude;
            box-shadow: 0 0 20px var(--glow-color);
        }

        @keyframes rotate {
            from { transform: rotate(0deg); }
            to { transform: rotate(360deg); }
        }

        .profile-info {
            flex: 1;
        }

        .profile-info h2 {
            font-size: 3rem;
            margin-bottom: 10px;
            background: linear-gradient(45deg, var(--accent-color), var(--primary-color));
            -webkit-background-clip: text;
            -webkit-text-fill-color: transparent;
            text-shadow: 0 0 10px var(--glow-color);
        }

        .tagline {
            font-size: 1.5rem;
            margin-bottom: 20px;
            color: var(--text-color);
            opacity: 0.9;
        }

        .bio {
            margin-bottom: 30px;
            font-size: 1.1rem;
            line-height: 1.8;
        }

        .social-links, .contact-links {
            margin-bottom: 30px;
        }

        .social-links h3, .contact-links h3 {
            margin-bottom: 20px;
            color: var(--accent-color);
            font-size: 1.5rem;
        }

        .social-grid, .contact-grid {
            display: grid;
            grid-template-columns: repeat(auto-fill, minmax(250px, 1fr));
            gap: 20px;
        }

        .social-item, .contact-item {
            display: flex;
            align-items: center;
            padding: 15px;
            background-color: var(--card-bg);
            border-radius: 12px;
            transition: transform 0.3s, box-shadow 0.3s;
            border: 1px solid var(--border-color);
            text-decoration: none;
            color: var(--text-color);
            backdrop-filter: blur(5px);
        }

        .social-item:hover, .contact-item:hover {
            transform: translateY(-5px);
            box-shadow: 0 10px 20px rgba(0, 0, 0, 0.3), 0 0 15px var(--glow-color);
            border-color: var(--accent-color);
        }

        .social-icon, .contact-icon {
            margin-right: 15px;
            font-size: 1.5rem;
            color: var(--accent-color);
            width: 40px;
            text-align: center;
        }

        .social-details, .contact-details {
            flex: 1;
        }

        .social-platform, .contact-platform {
            font-weight: bold;
            font-size: 1rem;
        }

        .social-username, .contact-username {
            font-size: 0.9rem;
            opacity: 0.8;
        }

        /* Skills Section */
        .skills-container {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
            gap: 30px;
        }

        .skill-category {
            background-color: var(--card-bg);
            border-radius: 15px;
            padding: 25px;
            border: 1px solid var(--border-color);
            backdrop-filter: blur(5px);
            box-shadow: 0 10px 20px rgba(0, 0, 0, 0.2);
            transition: transform 0.3s, box-shadow 0.3s;
        }

        .skill-category:hover {
            transform: translateY(-5px);
            box-shadow: 0 15px 30px rgba(0, 0, 0, 0.3), 0 0 15px var(--glow-color);
        }

        .skill-category h3 {
            margin-bottom: 20px;
            color: var(--accent-color);
            font-size: 1.5rem;
            text-align: center;
        }

        .skill-list {
            margin-top: 20px;
        }

        .skill-item {
            margin-bottom: 25px;
        }

        .skill-name {
            display: flex;
            justify-content: space-between;
            margin-bottom: 10px;
            font-weight: 500;
        }

        .skill-bar {
            height: 12px;
            background-color: rgba(255, 255, 255, 0.1);
            border-radius: 6px;
            overflow: hidden;
            position: relative;
        }

        .skill-level {
            height: 100%;
            background: linear-gradient(90deg, var(--accent-color), var(--primary-color));
            border-radius: 6px;
            width: 0;
            transition: width 1.5s ease-in-out;
            position: relative;
            box-shadow: 0 0 10px var(--glow-color);
        }

        .skill-level::after {
            content: '';
            position: absolute;
            top: 0;
            left: 0;
            bottom: 0;
            right: 0;
            background: linear-gradient(90deg, transparent, rgba(255,255,255,0.4), transparent);
            animation: shine 2s infinite;
        }

        @keyframes shine {
            0% { transform: translateX(-100%); }
            100% { transform: translateX(100%); }
        }

        /* Projects Section */
        .projects-container {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
            gap: 30px;
        }

        .project-card {
            background-color: var(--card-bg);
            border-radius: 15px;
            overflow: hidden;
            box-shadow: 0 10px 20px rgba(0, 0, 0, 0.2);
            transition: transform 0.3s, box-shadow 0.3s;
            border: 1px solid var(--border-color);
            backdrop-filter: blur(5px);
        }

        .project-card:hover {
            transform: translateY(-10px);
            box-shadow: 0 15px 30px rgba(0, 0, 0, 0.3), 0 0 20px var(--glow-color);
            border-color: var(--accent-color);
        }

        .project-image {
            height: 200px;
            overflow: hidden;
            position: relative;
        }

        .project-image::after {
            content: '';
            position: absolute;
            top: 0;
            left: 0;
            width: 100%;
            height: 100%;
            background: linear-gradient(to bottom, transparent, var(--card-bg));
        }

        .project-image img {
            width: 100%;
            height: 100%;
            object-fit: cover;
            transition: transform 0.5s;
        }

        .project-card:hover .project-image img {
            transform: scale(1.1);
        }

        .project-info {
            padding: 25px;
        }

        .project-info h3 {
            margin-bottom: 15px;
            color: var(--accent-color);
            font-size: 1.4rem;
        }

        .project-info p {
            margin-bottom: 20px;
            opacity: 0.9;
            line-height: 1.6;
        }

        .project-link {
            display: inline-block;
            padding: 10px 20px;
            background: linear-gradient(45deg, var(--accent-color), var(--primary-color));
            color: white;
            text-decoration: none;
            border-radius: 8px;
            font-weight: 500;
            transition: all 0.3s;
            box-shadow: 0 5px 15px rgba(0, 0, 0, 0.2);
        }

        .project-link:hover {
            transform: translateY(-3px);
            box-shadow: 0 8px 20px rgba(0, 0, 0, 0.3), 0 0 10px var(--glow-color);
        }

		.section-title {
		color: #fff;
		text-align: center;
		font-weight: 500;
		}

		.id-card-container {
		display: flex;
		justify-content: center;
		margin-top: 20px;
		}

		.id-card {
		background: #1b1f2a;
		border-radius: 10px;
		box-shadow: 0 0 20px rgba(0,0,0,0.3);
		width: 360px;
		padding: 0;
		overflow: hidden;
		color: #fff;
		}

		.id-header {
		background: #2a2f3c;
		padding: 8px 12px;
		display: flex;
		align-items: center;
		gap: 8px;
		}

		.id-header .dot {
		width: 10px;
		height: 10px;
		border-radius: 50%;
		display: inline-block;
		}
		.id-header .dot.red { background: #ff5f56; }
		.id-header .dot.yellow { background: #ffbd2e; }
		.id-header .dot.green { background: #27c93f; }

		.header-title {
		margin-left: auto;
		font-size: 14px;
		opacity: 0.8;
		}

		.id-content {
		padding: 20px;
		}

		pre.code {
		margin: 0;
		color: #c3d4ff;
		font-size: 14px;
		line-height: 1.6;
		}	

		.copyright {
		text-align: center;
		font-size: 12px;
		opacity: 0.6;
		padding-bottom: 10px;
		}

        .signature-box {
            width: 150px;
            height: 60px;
            border: 1px solid var(--border-color);
            border-radius: 5px;
            background: rgba(255, 255, 255, 0.05);
            position: relative;
            overflow: hidden;
        }

        .signature-box::after {
            content: 'TuanVinn';
            position: absolute;
            top: 50%;
            left: 50%;
            transform: translate(-50%, -50%);
            font-family: 'Dancing Script', cursive;
            font-size: 1.2rem;
            color: var(--text-color);
            opacity: 0.7;
        }

        .id-issued {
            text-align: right;
        }

        .id-issued p {
            font-size: 0.8rem;
            margin-bottom: 5px;
        }

        .id-issued p:first-child {
            font-weight: bold;
            color: var(--accent-color);
        }

        /* Footer */
        footer {
            text-align: center;
            padding: 40px 0;
            border-top: 1px solid var(--border-color);
            margin-top: 50px;
            background: rgba(10, 10, 26, 0.5);
            backdrop-filter: blur(5px);
        }

        footer p {
            opacity: 0.8;
        }

        /* Responsive Design */
        @media (max-width: 768px) {
            header {
                flex-direction: column;
                padding: 15px 0;
            }
            
            nav ul {
                margin-top: 15px;
                flex-wrap: wrap;
                justify-content: center;
            }
            
            nav ul li {
                margin: 0 10px 10px;
            }
            
            
            .id-content {
                flex-direction: column;
            }
            
            .id-photo {
                margin-right: 0;
                margin-bottom: 20px;
                align-self: center;
            }
            
            .id-details {
                grid-template-columns: 1fr;
            }
            
            .id-footer {
                flex-direction: column;
                align-items: center;
                gap: 15px;
            }
            
            .id-issued {
                text-align: center;
            }
            
            .skills-container, .projects-container {
                grid-template-columns: 1fr;
            }
        }