:root {
    /* MÀU CHỦ ĐẠO: VÀNG CAM HIỆN ĐẠI */
    --color-primary: #FFC107;
    --color-secondary: #0D1328; /* Màu nền Footer */
    --color-light: #FFFFFF;
    --color-dark: #1a1a1a;
    --color-gray: #6c757d;
    
    /* THÔNG SỐ ANIMATION & TRANSITION */
    --transition-speed: 0.3s; 
    --anime-easing: cubic-bezier(0.86, 0, 0.07, 1); /* Hàm Easing MƯỢT VÀ SẮC NÉT (Cinema Style) */
    --anime-duration: 0.8s; 
    
    /* THÔNG SỐ GIAO DIỆN */
    --border-radius-modern: 8px;
    --modern-radius: 12px;
    
    /* BIẾN CHIỀU CAO NAVBAR (FIX BỐ CỤC) */
    --navbar-height: 90px; 
}

/* ---------------------------------------------------- */
/* ⭐ 0. TỐI ƯU HÓA CHUYỂN ĐỘNG TOÀN CỤC ⭐ */
/* ---------------------------------------------------- */
html {
    /* Bật tính năng cuộn mượt khi click vào link neo (Smooth Scroll) */
    scroll-behavior: smooth; 
}

* {
    font-family: 'Montserrat', sans-serif;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}
h1, h2, h3, h4, h5, h6 {
    font-family: 'Oswald', sans-serif;
}


/* ---------------------------------------------------- */
/* 1. THANH ĐIỀU HƯỚNG (NAVBAR) */
/* ---------------------------------------------------- */

#mainNavbar { 
    z-index: 1050; 
    transform: translateZ(0); /* Tối ưu GPU */
    transition: background-color var(--transition-speed) var(--anime-easing), box-shadow var(--transition-speed) var(--anime-easing);
}

.navbar-solid {
    background-color: var(--color-secondary) !important;
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.3);
    padding: 1rem 0;
}

.nav-link {
    transition: all 0.3s var(--anime-easing); 
    position: relative;
    border-radius: var(--border-radius-modern); 
}

.nav-link:hover {
    color: var(--color-primary) !important; 
    transform: translateY(-2px) translateZ(0); 
}


/* ---------------------------------------------------- */
/* 2. HERO SECTION */
/* ---------------------------------------------------- */

.hero-section {
    position: relative;
    min-height: 100vh; 
    display: flex;
    align-items: center; 
    justify-content: center;
    padding-top: var(--navbar-height); 
    background-attachment: fixed; /* Hiệu ứng Parallax */
    background-size: cover;
    background-position: center center;
}

.hero-overlay {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: linear-gradient(135deg, rgba(13, 19, 40, 0.9), rgba(255, 193, 7, 0.3));
    transform: translateZ(0); 
}

.hero-content {
    position: relative;
    z-index: 10;
    text-align: center;
    color: var(--color-light);
    transform: translateZ(0); 
}

.btn-hero:hover {
    transform: translateY(-5px) scale(1.02) translateZ(0);
}


/* ---------------------------------------------------- */
/* 3. SERVICES SECTION */
/* ---------------------------------------------------- */

.service-card {
    background-color: var(--color-light);
    padding: 2.5rem 1.5rem;
    border-radius: var(--modern-radius); 
    text-align: center;
    transition: all 0.4s var(--anime-easing); 
    height: 100%; /* Đảm bảo chiều cao đồng đều */
    box-shadow: 0 3px 10px rgba(0, 0, 0, 0.1);
}

.service-card:hover {
    transform: translateY(-15px) translateZ(0); 
    box-shadow: 0 15px 40px rgba(255, 193, 7, 0.3); 
}

.service-icon {
    width: 70px;
    height: 70px;
    margin: 0 auto 1.5rem auto;
    display: flex;
    align-items: center;
    justify-content: center;
    background: linear-gradient(135deg, var(--color-primary), #e6b000);
    border-radius: 50%;
    color: var(--color-dark); 
    font-size: 2rem;
    transition: all 0.7s var(--anime-easing); 
}

.service-card:hover .service-icon {
    transform: rotate(360deg) scale(1.1) translateZ(0); 
}

/* ---------------------------------------------------- */
/* 4. PORTFOLIO SECTION (FIX & HIỆU ỨNG HOVER) */
/* ---------------------------------------------------- */

.portfolio-card {
    position: relative;
    overflow: hidden;
    border-radius: var(--modern-radius); 
    cursor: pointer;
    height: 350px;
    box-shadow: 0 3px 10px rgba(0, 0, 0, 0.1);
}

.portfolio-card img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: all 0.7s var(--anime-easing); 
}

.portfolio-overlay {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    /* FIX: NỀN MỜ MÀU VÀNG (TRANSPARENT YELLOW) */
    background: rgba(255, 193, 7, 0.85); 
    display: flex;
    align-items: center;
    justify-content: center;
    opacity: 0;
    transition: all 0.4s var(--anime-easing);
}

.portfolio-card:hover .portfolio-overlay {
    opacity: 1; /* Hiện Overlay khi hover */
}

.portfolio-card:hover img {
    transform: scale(1.15) rotate(0.5deg) translateZ(0); 
}

.portfolio-content {
    text-align: center;
    color: var(--color-dark); /* Màu chữ tối cho nền vàng */
    transform: translateY(30px); 
    opacity: 0;
    transition: all 0.5s var(--anime-easing) 0.1s; 
}

.portfolio-card:hover .portfolio-content {
    transform: translateY(0);
    opacity: 1;
}

.portfolio-title {
    font-size: 1.5rem;
    margin-bottom: 0.5rem;
    color: var(--color-dark); 
}

.portfolio-category {
    font-size: 0.9rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 2px;
    color: var(--color-secondary); /* Màu tối cho category */
}


/* ---------------------------------------------------- */
/* 5. TEAM SECTION (FIX LỖI BỐ CỤC MEMBER) */
/* ---------------------------------------------------- */

.team-card {
    background-color: var(--color-light);
    border-radius: var(--modern-radius); 
    overflow: hidden;
    box-shadow: 0 3px 10px rgba(0, 0, 0, 0.1);
    transition: all 0.4s var(--anime-easing);
    height: 100%;
    /* FIX: Đảm bảo hình ảnh không bị dính vào thẻ */
    display: flex; 
    flex-direction: column;
}

.team-card img {
    width: 100%;
    height: auto;
    object-fit: cover;
}

.team-card:hover {
    transform: translateY(-15px) translateZ(0); 
    box-shadow: 0 15px 40px rgba(255, 193, 7, 0.3);
}

.team-content {
    padding: 1.5rem;
    text-align: center;
    flex-grow: 1; /* FIX: Đẩy nội dung xuống cuối */
}

.team-name {
    font-size: 1.4rem;
    font-weight: 700;
    margin-bottom: 0.25rem;
}

.team-role {
    font-weight: 600;
    color: var(--color-primary);
    margin-bottom: 0.5rem;
}

/* ---------------------------------------------------- */
/* 6. FOOTER (FIX MẤT MÀU NỀN) */
/* ---------------------------------------------------- */

.footer {
    background-color: var(--color-secondary); /* KHÔI PHỤC MÀU NỀN */
    color: var(--color-light);
    padding: 2rem 0;
}

.social-icon {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 40px;
    height: 40px;
    margin-left: 10px;
    background-color: var(--color-dark);
    color: var(--color-light);
    border-radius: 50%;
    transition: all 0.4s var(--anime-easing);
    text-decoration: none;
}

.social-icon:hover {
    background-color: var(--color-primary);
    color: var(--color-dark); 
    transform: translateY(-7px) rotate(5deg) translateZ(0); 
}


/* ---------------------------------------------------- */
/* 7. MEDIA QUERIES */
/* ---------------------------------------------------- */

@media (max-width: 991px) {
    .hero-section {
        background-attachment: scroll; 
    }
    
    /* Tắt hiệu ứng hover trên mobile để đảm bảo tính tương thích và hiệu suất */
    .portfolio-card:hover .portfolio-overlay,
    .portfolio-card .portfolio-overlay {
        opacity: 1; 
        background: rgba(255, 193, 7, 0.95); /* Màu đậm hơn trên mobile */
    }
    
    .portfolio-card .portfolio-content {
        transform: translateY(0); 
        opacity: 1; 
    }
    
    .portfolio-card:hover img {
        transform: scale(1.05); 
    }
}

@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translate3d(0, 20px, 0);
    }
    to {
        opacity: 1;
        transform: translate3d(0, 0, 0);
    }
}