:root {
     --primary: #6366f1;
     --primary-dark: #4f46e5;
     --secondary: #10b981;
     --dark: #0f172a;
     --darker: #0a0f1c;
     --light: #f8fafc;
     --gray: #94a3b8;
     --gray-dark: #475569;
 }

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

 body {
     font-family: 'Poppins', sans-serif;
     background-color: var(--darker);
     color: var(--light);
     min-height: 100vh;
     line-height: 1.6;
 }

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

 /* Navigation */
 nav {
     position: fixed;
     top: 0;
     left: 0;
     width: 100%;
     padding: 20px 0;
     z-index: 1000;
     background: rgba(15, 23, 42, 0.95);
     backdrop-filter: blur(10px);
     border-bottom: 1px solid rgba(255, 255, 255, 0.05);
 }

 .nav-container {
     display: flex;
     justify-content: space-between;
     align-items: center;
 }

 .logo {
     font-size: 1.5rem;
     font-weight: 700;
     color: white;
     display: flex;
     align-items: center;
     gap: 10px;
 }

 .logo-dot {
     color: var(--primary);
 }

 .nav-links {
     display: flex;
     gap: 30px;
 }

 .nav-links a {
     color: var(--gray);
     text-decoration: none;
     font-weight: 500;
     transition: color 0.3s;
     position: relative;
 }

 .nav-links a:hover {
     color: white;
 }

 .nav-links a::after {
     content: '';
     position: absolute;
     bottom: -5px;
     left: 0;
     width: 0;
     height: 2px;
     background: var(--primary);
     transition: width 0.3s;
 }

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

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

 /* Hero Section */
 .hero {
     padding: 180px 20px 100px;
     text-align: center;
     position: relative;
     overflow: hidden;
 }

 .hero-bg {
     position: absolute;
     top: 0;
     left: 0;
     width: 100%;
     height: 100%;
     background:
         radial-gradient(circle at 20% 80%, rgba(99, 102, 241, 0.1) 0%, transparent 50%),
         radial-gradient(circle at 80% 20%, rgba(16, 185, 129, 0.1) 0%, transparent 50%),
         radial-gradient(circle at 40% 40%, rgba(139, 92, 246, 0.05) 0%, transparent 50%);
     z-index: -1;
 }

 .avatar-container {
     position: relative;
     display: inline-block;
     margin-bottom: 30px;
 }

 .avatar {
     width: 180px;
     height: 180px;
     border-radius: 50%;
     border: 4px solid var(--primary);
     box-shadow: 0 0 30px rgba(99, 102, 241, 0.3);
     object-fit: cover;
     transition: 0.5s;
 }

 .avatar:hover {
     transform: scale(1.05);
     box-shadow: 0 0 40px rgba(99, 102, 241, 0.5);
 }

 .tech-badge {
     position: absolute;
     background: var(--dark);
     color: white;
     padding: 8px 15px;
     border-radius: 20px;
     font-size: 0.8rem;
     font-weight: 600;
     box-shadow: 0 5px 15px rgba(0, 0, 0, 0.3);
     border: 1px solid var(--gray-dark);
     animation: float 3s ease-in-out infinite;
 }

 .badge-react {
     top: 10px;
     right: 10px;
     animation-delay: 0s;
     color: #61dafb;
 }

 .badge-dotnet {
     bottom: 10px;
     left: 10px;
     animation-delay: 1.5s;
     color: #512bd4;
 }

 .hero h1 {
     font-size: 4rem;
     font-weight: 700;
     margin-bottom: 15px;
     background: linear-gradient(90deg, #fff, var(--primary));
     -webkit-background-clip: text;
     -webkit-text-fill-color: transparent;
     animation: fadeInDown 1s ease-out;
 }

 .hero p {
     font-size: 1.4rem;
     color: var(--gray);
     max-width: 700px;
     margin: 0 auto 40px;
     animation: fadeInUp 1s ease-out 0.3s both;
 }

 .typing-text {
     color: var(--primary);
     font-weight: 600;
 }

 .cta-buttons {
     display: flex;
     justify-content: center;
     gap: 20px;
     margin-top: 30px;
 }

 .btn {
     padding: 12px 30px;
     border-radius: 50px;
     font-weight: 600;
     text-decoration: none;
     transition: all 0.3s;
     display: inline-flex;
     align-items: center;
     gap: 10px;
 }

 .btn-primary {
     background: var(--primary);
     color: white;
     box-shadow: 0 10px 20px rgba(99, 102, 241, 0.3);
 }

 .btn-primary:hover {
     background: var(--primary-dark);
     transform: translateY(-3px);
     box-shadow: 0 15px 30px rgba(99, 102, 241, 0.4);
 }

 .btn-secondary {
     background: transparent;
     color: var(--gray);
     border: 2px solid var(--gray-dark);
 }

 .btn-secondary:hover {
     background: rgba(255, 255, 255, 0.05);
     color: white;
     border-color: var(--primary);
     transform: translateY(-3px);
 }

 /* Card giới thiệu */
 .card {
     background: var(--dark);
     border-radius: 16px;
     padding: 50px 40px;
     margin: 40px auto;
     max-width: 900px;
     border: 1px solid rgba(255, 255, 255, 0.05);
     box-shadow: 0 10px 30px rgba(0, 0, 0, 0.2);
     animation: fadeInUp 1s ease-out 0.6s both;
 }

 .card h2 {
     font-size: 2.5rem;
     text-align: center;
     margin-bottom: 25px;
     color: #fff;
     position: relative;
 }

 .card h2::after {
     content: '';
     position: absolute;
     bottom: -10px;
     left: 50%;
     transform: translateX(-50%);
     width: 80px;
     height: 4px;
     background: var(--primary);
     border-radius: 2px;
 }

 .card p {
     font-size: 1.15rem;
     line-height: 1.8;
     color: var(--gray);
     margin-bottom: 20px;
 }

 .skills-section {
     margin-top: 40px;
 }

 .skills-grid {
     display: grid;
     grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
     gap: 20px;
     margin-top: 20px;
 }

 .skill-item {
     background: rgba(255, 255, 255, 0.03);
     padding: 25px 20px;
     border-radius: 12px;
     text-align: center;
     transition: all 0.3s;
     border: 1px solid rgba(255, 255, 255, 0.05);
 }

 .skill-item:hover {
     transform: translateY(-5px);
     border-color: var(--primary);
     box-shadow: 0 10px 20px rgba(0, 0, 0, 0.2);
 }

 .skill-icon {
     font-size: 2.5rem;
     margin-bottom: 15px;
     color: var(--primary);
 }

 .skill-item h4 {
     font-size: 1.2rem;
     margin-bottom: 10px;
 }

 .skill-item p {
     font-size: 0.9rem;
     color: var(--gray);
 }

 /* Projects Preview */
 .projects-preview {
     margin: 80px 0;
 }

 .section-title {
     text-align: center;
     font-size: 2.5rem;
     margin-bottom: 50px;
     position: relative;
 }

 .section-title::after {
     content: '';
     position: absolute;
     bottom: -10px;
     left: 50%;
     transform: translateX(-50%);
     width: 80px;
     height: 4px;
     background: var(--primary);
     border-radius: 2px;
 }

 .projects-grid {
     display: grid;
     grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
     gap: 30px;
 }

 .project-card {
     background: var(--dark);
     border-radius: 16px;
     overflow: hidden;
     transition: all 0.3s;
     border: 1px solid rgba(255, 255, 255, 0.05);
     cursor: pointer;
 }

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

 .project-image {
     height: 200px;
     background: linear-gradient(45deg, var(--primary), var(--secondary));
     display: flex;
     align-items: center;
     justify-content: center;
     color: white;
     font-size: 3rem;
     position: relative;
     overflow: hidden;
 }

 .project-image::after {
     content: '';
     position: absolute;
     top: 0;
     left: 0;
     width: 100%;
     height: 100%;
     background: linear-gradient(45deg, rgba(99, 102, 241, 0.8), rgba(16, 185, 129, 0.8));
 }

 .project-image img {
     z-index: 1;
     width: 100%;
     height: 100%;
     object-fit: cover;
 }

 .project-content {
     padding: 25px;
 }

 .project-title {
     font-size: 1.3rem;
     margin-bottom: 10px;
 }

 .project-description {
     color: var(--gray);
     margin-bottom: 15px;
     font-size: 0.95rem;
 }

 .project-tech {
     display: flex;
     flex-wrap: wrap;
     gap: 8px;
     margin-bottom: 15px;
 }

 .tech-tag {
     background: rgba(99, 102, 241, 0.1);
     color: var(--primary);
     padding: 4px 10px;
     border-radius: 20px;
     font-size: 0.8rem;
     border: 1px solid rgba(99, 102, 241, 0.2);
 }

 .project-link {
     color: var(--primary);
     text-decoration: none;
     font-weight: 600;
     display: inline-flex;
     align-items: center;
     gap: 5px;
     transition: all 0.3s;
 }

 .project-link:hover {
     gap: 10px;
 }

 /* Social Links */
 .social-links {
     text-align: center;
     margin: 50px 0;
 }

 .social-links a {
     display: inline-flex;
     align-items: center;
     justify-content: center;
     width: 60px;
     height: 60px;
     background: var(--dark);
     color: var(--gray);
     font-size: 1.6rem;
     border-radius: 50%;
     margin: 0 15px;
     transition: all 0.4s;
     border: 1px solid rgba(255, 255, 255, 0.05);
 }

 .social-links a:hover {
     background: var(--primary);
     color: white;
     transform: translateY(-10px) scale(1.1);
     box-shadow: 0 15px 30px rgba(0, 0, 0, 0.3);
 }

 footer {
     text-align: center;
     padding: 50px 20px;
     font-size: 0.95rem;
     color: var(--gray);
     border-top: 1px solid rgba(255, 255, 255, 0.05);
 }

 /* Animation */
 @keyframes fadeInDown {
     from {
         opacity: 0;
         transform: translateY(-50px);
     }

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

 @keyframes fadeInUp {
     from {
         opacity: 0;
         transform: translateY(50px);
     }

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

 @keyframes float {
     0% {
         transform: translateY(0px);
     }

     50% {
         transform: translateY(-10px);
     }

     100% {
         transform: translateY(0px);
     }
 }

 @media (max-width: 768px) {
     .nav-links {
         display: none;
         position: absolute;
         top: 100%;
         left: 0;
         width: 100%;
         background: var(--dark);
         flex-direction: column;
         padding: 20px;
         text-align: center;
         border-top: 1px solid rgba(255, 255, 255, 0.05);
     }

     .nav-links.active {
         display: flex;
     }

     .mobile-menu-btn {
         display: block;
     }

     .hero h1 {
         font-size: 2.8rem;
     }

     .hero p {
         font-size: 1.2rem;
     }

     .card {
         padding: 40px 25px;
     }

     .social-links a {
         width: 50px;
         height: 50px;
         font-size: 1.4rem;
         margin: 0 10px;
     }

     .cta-buttons {
         flex-direction: column;
         align-items: center;
     }

     .btn {
         width: 100%;
         max-width: 250px;
         justify-content: center;
     }
 }


 /* ClinicManagement */
 .project-hero {
     background: linear-gradient(135deg, var(--darker) 0%, var(--dark) 100%);
     padding: 150px 20px 80px;
     text-align: center;
     position: relative;
     overflow: hidden;
 }

 .project-hero-bg {
     position: absolute;
     top: 0;
     left: 0;
     width: 100%;
     height: 100%;
     background:
         radial-gradient(circle at 20% 80%, rgba(99, 102, 241, 0.15) 0%, transparent 50%),
         radial-gradient(circle at 80% 20%, rgba(16, 185, 129, 0.15) 0%, transparent 50%);
     z-index: 1;
 }

 .project-hero-content {
     position: relative;
     z-index: 2;
     max-width: 800px;
     margin: 0 auto;
 }

 .project-title {
     font-size: 3.5rem;
     font-weight: 700;
     margin-bottom: 20px;
     background: linear-gradient(90deg, #fff, var(--primary));
     -webkit-background-clip: text;
     -webkit-text-fill-color: transparent;
 }

 .project-subtitle {
     font-size: 1.3rem;
     color: var(--gray);
     margin-bottom: 30px;
     line-height: 1.6;
 }

 .project-hero .tech-badge {
     position: static !important;
 }

 .tech-stack {
     display: flex;
     justify-content: center;
     flex-wrap: wrap;
     gap: 15px;
     margin: 30px 0;
 }

 .tech-badge {
     background: rgba(99, 102, 241, 0.1);
     color: var(--primary);
     padding: 10px 20px;
     border-radius: 25px;
     font-weight: 600;
     border: 1px solid rgba(99, 102, 241, 0.3);
     backdrop-filter: blur(10px);
     transition: all 0.3s;
 }

 .tech-badge:hover {
     background: rgba(99, 102, 241, 0.2);
     transform: translateY(-2px);
 }

 .project-content {
     max-width: 1200px;
     margin: 0 auto;
     padding: 80px 20px;
 }

 .section {
     margin-bottom: 80px;
 }

 .section-title {
     font-size: 2.2rem;
     margin-bottom: 30px;
     color: white;
     position: relative;
     padding-bottom: 15px;
     display: flex;
     align-items: center;
     gap: 15px;
 }

 .section-title::after {
     content: '';
     position: absolute;
     bottom: 0;
     left: 0;
     width: 60px;
     height: 4px;
     background: var(--primary);
     border-radius: 2px;
 }

 .section-content {
     background: var(--dark);
     padding: 40px;
     border-radius: 16px;
     border: 1px solid rgba(255, 255, 255, 0.05);
     box-shadow: 0 10px 30px rgba(0, 0, 0, 0.2);
 }

 .goals-grid {
     display: grid;
     grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
     gap: 25px;
 }

 .goal-card {
     background: rgba(255, 255, 255, 0.03);
     padding: 30px;
     border-radius: 12px;
     border: 1px solid rgba(255, 255, 255, 0.05);
     transition: all 0.3s;
     text-align: center;
 }

 .goal-card:hover {
     transform: translateY(-5px);
     border-color: var(--primary);
     box-shadow: 0 15px 30px rgba(0, 0, 0, 0.3);
 }

 .goal-icon {
     font-size: 2.5rem;
     color: var(--primary);
     margin-bottom: 20px;
     background: rgba(99, 102, 241, 0.1);
     width: 80px;
     height: 80px;
     border-radius: 50%;
     display: flex;
     align-items: center;
     justify-content: center;
     margin: 0 auto 20px;
 }

 .goal-card h3 {
     color: white;
     margin-bottom: 15px;
     font-size: 1.3rem;
 }

 .goal-card p {
     color: var(--gray);
     line-height: 1.6;
 }

 .features-grid {
     display: grid;
     grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
     gap: 20px;
 }

 .feature-card {
     background: rgba(255, 255, 255, 0.03);
     padding: 25px;
     border-radius: 12px;
     border-left: 4px solid var(--primary);
     transition: all 0.3s;
 }

 .feature-card:hover {
     transform: translateY(-3px);
     background: rgba(255, 255, 255, 0.05);
 }

 .feature-card h4 {
     color: var(--primary);
     margin-bottom: 15px;
     font-size: 1.1rem;
     display: flex;
     align-items: center;
     gap: 10px;
 }

 .feature-card ul {
     list-style: none;
     padding: 0;
 }

 .feature-card li {
     padding: 8px 0;
     color: var(--gray);
     position: relative;
     padding-left: 25px;
     line-height: 1.5;
 }

 .feature-card li::before {
     content: '✓';
     position: absolute;
     left: 0;
     color: var(--secondary);
     font-weight: bold;
 }

 .process-steps {
     display: flex;
     flex-direction: column;
     gap: 20px;
 }

 .process-step {
     display: flex;
     align-items: flex-start;
     gap: 20px;
     padding: 25px;
     background: rgba(255, 255, 255, 0.03);
     border-radius: 12px;
     border: 1px solid rgba(255, 255, 255, 0.05);
     transition: all 0.3s;
 }

 .process-step:hover {
     border-color: var(--primary);
     transform: translateX(5px);
 }

 .step-number {
     background: var(--primary);
     color: white;
     width: 40px;
     height: 40px;
     border-radius: 50%;
     display: flex;
     align-items: center;
     justify-content: center;
     font-weight: bold;
     flex-shrink: 0;
     font-size: 1.1rem;
 }

 .process-step h4 {
     color: white;
     margin-bottom: 8px;
     font-size: 1.2rem;
 }

 .process-step p {
     color: var(--gray);
     line-height: 1.6;
 }

 /* Gallery Styles */
 .gallery {
     display: grid;
     grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
     gap: 20px;
     margin-top: 30px;
 }

 .gallery-item {
     border-radius: 12px;
     overflow: hidden;
     border: 1px solid rgba(255, 255, 255, 0.05);
     transition: all 0.3s;
     cursor: pointer;
     position: relative;
 }

 .gallery-item:hover {
     transform: translateY(-5px);
     border-color: var(--primary);
     box-shadow: 0 15px 30px rgba(0, 0, 0, 0.3);
 }

 .gallery-item:hover::after {
     content: '👁️ Click để xem';
     position: absolute;
     top: 50%;
     left: 50%;
     transform: translate(-50%, -50%);
     background: rgba(0, 0, 0, 0.8);
     color: white;
     padding: 10px 20px;
     border-radius: 25px;
     font-weight: 600;
 }

 .gallery-item img {
     width: 100%;
     height: 200px;
     object-fit: cover;
     display: block;
     transition: transform 0.3s;
 }

 .gallery-item:hover img {
     transform: scale(1.05);
 }

 /* Lightbox Styles */
 .lightbox {
     display: none;
     position: fixed;
     top: 0;
     left: 0;
     width: 100%;
     height: 100%;
     background: rgba(0, 0, 0, 0.9);
     z-index: 10000;
     align-items: center;
     justify-content: center;
 }

 .lightbox.active {
     display: flex;
 }

 .lightbox-content {
     max-width: 90%;
     max-height: 90%;
     position: relative;
 }

 .lightbox-img {
     max-width: 100%;
     max-height: 90vh;
     border-radius: 8px;
     box-shadow: 0 20px 50px rgba(0, 0, 0, 0.5);
 }

 .lightbox-close {
     position: absolute;
     top: -40px;
     right: 0;
     background: none;
     border: none;
     color: white;
     font-size: 2rem;
     cursor: pointer;
     padding: 5px;
 }

 .lightbox-nav {
     position: absolute;
     top: 50%;
     width: 100%;
     display: flex;
     justify-content: space-between;
     transform: translateY(-50%);
     padding: 0 20px;
 }

 .lightbox-prev,
 .lightbox-next {
     background: rgba(255, 255, 255, 0.1);
     border: none;
     color: white;
     width: 50px;
     height: 50px;
     border-radius: 50%;
     font-size: 1.5rem;
     cursor: pointer;
     backdrop-filter: blur(10px);
     transition: all 0.3s;
 }

 .lightbox-prev:hover,
 .lightbox-next:hover {
     background: var(--primary);
     transform: scale(1.1);
 }

 .lightbox-counter {
     position: absolute;
     bottom: -40px;
     left: 50%;
     transform: translateX(-50%);
     color: white;
     font-size: 1rem;
     background: rgba(255, 255, 255, 0.1);
     padding: 5px 15px;
     border-radius: 20px;
     backdrop-filter: blur(10px);
 }

 .demo-accounts {
     display: grid;
     grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
     gap: 20px;
     margin-top: 30px;
 }

 .account-card {
     background: rgba(255, 255, 255, 0.03);
     padding: 25px;
     border-radius: 12px;
     text-align: center;
     border: 1px solid rgba(255, 255, 255, 0.05);
     transition: all 0.3s;
 }

 .account-card:hover {
     transform: translateY(-5px);
     border-color: var(--primary);
 }

 .account-role {
     color: var(--primary);
     font-weight: 600;
     margin-bottom: 15px;
     font-size: 1.1rem;
 }

 .account-email {
     color: var(--gray);
     font-family: monospace;
     margin: 10px 0;
     background: rgba(255, 255, 255, 0.05);
     padding: 8px;
     border-radius: 6px;
     font-size: 0.9rem;
 }

 .account-password {
     color: var(--secondary);
     font-family: monospace;
     background: rgba(16, 185, 129, 0.1);
     padding: 8px;
     border-radius: 6px;
     font-size: 0.9rem;
 }

 .project-links {
     display: flex;
     justify-content: center;
     gap: 20px;
     margin-top: 40px;
     flex-wrap: wrap;
 }

 .project-link {
     display: inline-flex;
     align-items: center;
     gap: 10px;
     padding: 15px 30px;
     background: var(--primary);
     color: white;
     text-decoration: none;
     border-radius: 50px;
     font-weight: 600;
     transition: all 0.3s;
     border: 2px solid transparent;
 }

 .project-link:hover {
     background: var(--primary-dark);
     transform: translateY(-3px);
     box-shadow: 0 10px 25px rgba(99, 102, 241, 0.3);
 }

 .project-link.secondary {
     background: transparent;
     border: 2px solid var(--gray-dark);
     color: var(--gray);
 }

 .project-link.secondary:hover {
     background: rgba(255, 255, 255, 0.05);
     border-color: var(--primary);
     color: white;
 }

 .back-button {
     display: inline-flex;
     align-items: center;
     gap: 10px;
     padding: 12px 25px;
     background: transparent;
     color: var(--gray);
     text-decoration: none;
     border-radius: 50px;
     font-weight: 600;
     transition: all 0.3s;
     border: 2px solid var(--gray-dark);
     margin-bottom: 30px;
 }

 .back-button:hover {
     background: rgba(255, 255, 255, 0.05);
     border-color: var(--primary);
     color: white;
     transform: translateX(-5px);
 }

 @media (max-width: 768px) {
     .project-title {
         font-size: 2.5rem;
     }

     .project-subtitle {
         font-size: 1.1rem;
     }

     .section-content {
         padding: 25px;
     }

     .process-step {
         flex-direction: column;
         text-align: center;
         gap: 15px;
     }

     .project-links {
         flex-direction: column;
         align-items: center;
     }

     .project-link {
         width: 100%;
         max-width: 300px;
         justify-content: center;
     }

     .lightbox-nav {
         padding: 0 10px;
     }

     .lightbox-prev,
     .lightbox-next {
         width: 40px;
         height: 40px;
         font-size: 1.2rem;
     }
 }

 /* Language Toggle */
 .nav-right {
     display: flex;
     align-items: center;
     gap: 15px;
 }

 .language-toggle {
     background: rgba(255, 255, 255, 0.05);
     border: 1px solid rgba(255, 255, 255, 0.1);
     color: var(--gray);
     padding: 8px 15px;
     border-radius: 20px;
     cursor: pointer;
     display: flex;
     align-items: center;
     gap: 8px;
     transition: all 0.3s;
     font-weight: 500;
 }

 .language-toggle:hover {
     background: rgba(255, 255, 255, 0.1);
     color: white;
     border-color: var(--primary);
 }

 .language-text {
     font-size: 0.9rem;
 }

 /* Education and Experience sections */
 .education-item,
 .experience-item {
     margin-bottom: 30px;
     padding-bottom: 20px;
     border-bottom: 1px solid rgba(255, 255, 255, 0.05);
 }

 .education-item:last-child,
 .experience-item:last-child {
     border-bottom: none;
 }

 .education-item h3,
 .experience-item h3 {
     color: white;
     margin-bottom: 10px;
     font-size: 1.2rem;
 }

 .education-item p,
 .experience-item p {
     color: var(--gray);
     margin-bottom: 10px;
 }

 .experience-item ul {
     padding-left: 20px;
 }

 .experience-item li {
     color: var(--gray);
     margin-bottom: 8px;
     line-height: 1.5;
 }

 /* Responsive adjustments */
 @media (max-width: 768px) {
     .nav-right {
         gap: 10px;
     }

     .language-toggle {
         padding: 6px 12px;
         font-size: 0.9rem;
     }
 }

 .social-links a[href^="mailto:"] {
     position: relative;
 }

 .social-links a[href^="mailto:"]:hover::after {
     content: 'Gửi email';
     position: absolute;
     bottom: -30px;
     left: 50%;
     transform: translateX(-50%);
     background: var(--dark);
     color: white;
     padding: 5px 10px;
     border-radius: 4px;
     font-size: 0.8rem;
     white-space: nowrap;
 }