:root {
    --primary-color: #4a5568;
    --secondary-color: #2d3748;
    --accent-color: #4299e1;
    --background-color: #f7fafc;
    --text-color: #2d3748;
}

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

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, 'Open Sans', 'Helvetica Neue', sans-serif;
    line-height: 1.6;
    background-color: var(--background-color);
    color: var(--text-color);
}

.container {
    width: 90%;
    max-width: 1200px;
    margin: 0 auto;
    padding: 2rem;
    text-align: center; /* Căn giữa tiêu đề */
}

.header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    background-color: white;
    box-shadow: 0 4px 6px rgba(0,0,0,0.05);
    padding: 1rem 2rem;
    position: sticky;
    top: 0;
    z-index: 100;
}

.logo {
    font-weight: 700;
    font-size: 1.5rem;
    color: var(--primary-color);
}

.nav-links {
    display: flex;
    gap: 1.5rem;
}

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

.nav-links a:hover {
    color: var(--accent-color);
}

.hero {
    display: flex;
    align-items: center;
    gap: 3rem;
    min-height: 80vh;
    background: linear-gradient(135deg, #f7fafc 0%, #edf2f7 100%);
}

.hero-content {
    flex: 1;
}

.hero-image {
    flex: 1;
    text-align: center;
}

.hero-image img {
    max-width: 400px;
    border-radius: 50%;
    box-shadow: 0 10px 25px rgba(0,0,0,0.1);
    transition: transform 0.5s ease;
}

.hero-image img:hover {
    transform: scale(1.05);
}

.hero h1 {
    font-size: 3rem;
    color: var(--primary-color);
    margin-bottom: 1rem;
}

.hero p {
    font-size: 1.2rem;
    color: var(--secondary-color);
    margin-bottom: 2rem;
}

.cta-buttons {
    display: flex;
    gap: 1rem;
    justify-content: center; /* Căn giữa nút */
}

.btn {
    display: inline-block;
    padding: 0.8rem 1.5rem;
    border-radius: 5px;
    text-decoration: none;
    font-weight: 600;
    transition: all 0.3s ease;
}

.btn-primary {
    background-color: var(--accent-color);
    color: white;
}

.btn-secondary {
    border: 2px solid var(--accent-color);
    color: var(--accent-color);
}

.section-title {
    text-align: center;
    margin-bottom: 2rem;
    color: var(--primary-color);
}

.skills, .projects {
    background-color: white;
    border-radius: 10px;
    padding: 2rem;
    margin: 2rem auto; /* Căn giữa và thêm khoảng cách */
    box-shadow: 0 10px 25px rgba(0,0,0,0.05);
    max-width: 1000px; /* Giới hạn chiều rộng */
}

.skills-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
    gap: 1rem;
}

.skill-card {
    text-align: center;
    padding: 1rem;
    background-color: #f7fafc;
    border-radius: 8px;
    transition: transform 0.3s ease;
}

.skill-card:hover {
    transform: translateY(-10px);
}

.skill-card i {
    font-size: 3rem;
    color: var(--accent-color);
    margin-bottom: 1rem;
}

.footer {
    background-color: var(--secondary-color);
    color: white;
    text-align: center;
    padding: 2rem;
}

.social-links {
    display: flex;
    justify-content: center;
    gap: 1.5rem;
    margin-top: 1rem;
}

.social-links a {
    color: white;
    font-size: 1.5rem;
    transition: color 0.3s ease;
}

.social-links a:hover {
    color: var(--accent-color);
}

/* Menu Mobile */
.menu-toggle {
    display: none;
    flex-direction: column;
    cursor: pointer;
}

.bar {
    width: 25px;
    height: 3px;
    background-color: var(--primary-color);
    margin: 3px 0;
    transition: 0.4s;
}

@media (max-width: 768px) {
    .header {
        flex-wrap: wrap;
        justify-content: center;
        text-align: center;
    }

    .nav-links {
        display: none;
        width: 100%;
        flex-direction: column;
        align-items: center;
    }

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

    .menu-toggle {
        display: flex;
        position: absolute;
        right: 20px;
        top: 20px;
    }

    .hero {
        flex-direction: column;
        text-align: center;
        gap: 1rem;
    }

    .hero-image img {
        max-width: 250px;
    }

    .hero h1 {
        font-size: 2rem;
    }

    .hero p {
        font-size: 1rem;
    }

    .cta-buttons {
        justify-content: center;
    }

    .skills-grid {
        grid-template-columns: 1fr 1fr;
    }
}

@media (max-width: 480px) {
    .skills-grid {
        grid-template-columns: 1fr;
    }

    .cta-buttons {
        flex-direction: column;
    }

    .btn {
        width: 100%;
        text-align: center;
    }
}

    /* Add these styles to your existing style.css */
.project-link {
    text-decoration: none;
    color: inherit;
    transition: transform 0.3s ease;
}

.project-link .skill-card {
    transition: all 0.3s ease;
}

.project-link:hover .skill-card {
    transform: scale(1.05);
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
    background-color: #f4f4f4;
}