/* Thiết lập chung và biến màu Boostadsx Style */
:root {
    --color-dark-bg: #12121e;
    --color-dark-card: #1c1c2b;
    --color-text-light: #ffffff;
    --color-text-dim: #a0a0b0;
    --color-primary: #00d2ff;
    --color-secondary: #00ffc2;
    --padding-section: 100px 0;
    --border-radius-lg: 15px;
    --border-radius-sm: 8px;
}

/* Reset và Font */
* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

body {
    font-family: 'Poppins', sans-serif;
    background-color: var(--color-dark-bg);
    color: var(--color-text-light);
    line-height: 1.6;
}

/* ===================================================================== */
/* ======================== CHUNG & HEADER =============================== */
/* ===================================================================== */
a {
    color: var(--color-primary);
    text-decoration: none;
    transition: color 0.2s ease-in-out;
}
a:hover {
    color: var(--color-secondary);
}
ul {
    list-style: none;
}
.section-padding {
    padding: var(--padding-section);
    max-width: 1200px;
    margin: 0 auto;
    padding-left: 20px;
    padding-right: 20px;
}
.text-center {
    text-align: center;
}
.text-left {
    text-align: left;
}
.section-title {
    font-size: 2.5rem;
    margin-bottom: 10px;
    font-weight: 700;
}
.section-title::after {
    content: '';
    display: block;
    width: 60px;
    height: 3px;
    background: linear-gradient(to right, var(--color-secondary), var(--color-primary));
    margin: 10px 0 0; 
}
.section-title.text-center::after {
    margin: 10px auto 0;
}
.section-subtitle {
    color: var(--color-text-dim);
    margin-bottom: 40px;
    max-width: 800px;
    margin-left: auto;
    margin-right: auto;
}
.text-gradient {
    background: linear-gradient(to right, var(--color-secondary), var(--color-primary));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}
.boost-btn-primary {
    background: linear-gradient(to right, var(--color-secondary), var(--color-primary));
    color: var(--color-dark-bg);
    padding: 12px 30px;
    border: none;
    border-radius: 50px;
    cursor: pointer;
    font-weight: 600;
    transition: box-shadow 0.3s ease-in-out, transform 0.2s;
}
.boost-btn-primary:hover {
    box-shadow: 0 0 15px rgba(0, 210, 255, 0.6);
    transform: translateY(-2px);
}
.boost-btn-secondary {
    background-color: var(--color-dark-card);
    color: var(--color-text-light);
    padding: 12px 30px;
    border: 1px solid var(--color-primary);
    border-radius: 50px;
    cursor: pointer;
    font-weight: 600;
    margin-right: 15px;
    transition: background-color 0.3s, border-color 0.3s, transform 0.2s;
}
.boost-btn-secondary:hover {
    background-color: var(--color-primary);
    border-color: var(--color-secondary);
    transform: translateY(-2px);
}
.boost-btn-outline {
    background: transparent;
    color: var(--color-text-dim);
    padding: 12px 30px;
    border: 1px solid var(--color-text-dim);
    border-radius: 50px;
    cursor: pointer;
    font-weight: 600;
    transition: border-color 0.3s, color 0.3s, transform 0.2s;
}
.boost-btn-outline:hover {
    border-color: var(--color-primary);
    color: var(--color-primary);
    transform: translateY(-2px);
}
.boost-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 20px 50px;
    background-color: var(--color-dark-bg);
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.2);
    position: sticky;
    top: 0;
    z-index: 1000;
}
.boost-logo {
    font-size: 1.5rem;
    font-weight: 800;
    color: var(--color-text-light);
}
.boost-nav a {
    margin: 0 20px;
    color: var(--color-text-dim);
    font-weight: 500;
}
.boost-nav a:hover {
    color: var(--color-text-light);
}
.boost-hero {
    padding-top: 180px;
    padding-bottom: 150px;
}
.boost-tagline {
    color: var(--color-secondary);
    font-weight: 600;
    margin-bottom: 15px;
    display: block;
    text-transform: uppercase;
    letter-spacing: 1px;
}
.boost-hero h1 {
    font-size: 4rem;
    margin-bottom: 25px;
    font-weight: 800;
}
.boost-hero p {
    max-width: 700px;
    margin: 0 auto 40px;
    color: var(--color-text-dim);
    font-size: 1.1rem;
}
.boost-stats {
    display: flex;
    justify-content: center;
    gap: 80px;
    margin-top: 80px;
}
.boost-stats span {
    display: block;
    font-size: 2.2rem;
    font-weight: 700;
    color: var(--color-primary);
}
.boost-stats small {
    color: var(--color-text-dim);
    text-transform: uppercase;
    font-size: 0.9rem;
}

/* ------------------- 1. THE ABOUT US DIFFERENCE ------------------- */
.boost-about-us {
    display: flex;
    align-items: center;
    gap: 60px;
    padding-bottom: 150px;
}
.boost-about-us .about-content {
    flex: 1;
}
.boost-about-us .about-content p {
    color: var(--color-text-dim);
    margin-bottom: 25px;
    font-size: 1.05rem;
}
.boost-about-us .about-features {
    list-style: none;
    margin-bottom: 30px;
}
.boost-about-us .about-features li {
    color: var(--color-text-dim);
    margin-bottom: 10px;
    font-size: 1rem;
}
.boost-about-us .about-features li i {
    color: var(--color-secondary);
    margin-right: 10px;
}
.boost-about-us .about-visual {
    flex: 1;
    display: flex;
    justify-content: center;
}
.boost-about-us .stats-card {
    background-color: var(--color-dark-card);
    padding: 40px;
    border-radius: var(--border-radius-lg);
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 30px;
    min-width: 450px;
    border: 1px solid rgba(255, 255, 255, 0.08);
}
.boost-about-us .stat-item {
    text-align: center;
    padding: 20px;
    border-radius: var(--border-radius-sm);
    background-color: var(--color-dark-bg);
}
.boost-about-us .stat-item:nth-child(even) {
    background-color: rgba(0, 255, 194, 0.08);
}
.boost-about-us .stat-item:nth-child(3) {
    grid-column: span 2; 
    background-color: rgba(0, 210, 255, 0.08);
}
.boost-about-us .stat-item-empty {
    display: none;
}
.boost-about-us .stat-number {
    display: block;
    font-size: 2.5rem;
    font-weight: 700;
    color: var(--color-primary);
    margin-bottom: 5px;
}
.boost-about-us .stat-item:nth-child(even) .stat-number {
    color: var(--color-secondary);
}
.boost-about-us .stat-description {
    color: var(--color-text-dim);
    font-size: 0.95rem;
}

/* ------------------- 2. OUR SIMPLE 4-STEP PROCESS ------------------- */
.boost-process-wrapper {
    background-color: #141f2b;
    padding-bottom: 100px;
}
.boost-process {
    background-color: #1a2736;
    border-radius: var(--border-radius-lg);
    padding: 80px 50px;
    max-width: 1200px;
    margin: 0 auto;
    box-shadow: 0 15px 40px rgba(0, 0, 0, 0.3);
}
.process-container {
    display: flex;
    gap: 50px;
    align-items: center;
}
.process-image {
    flex: 1;
    border-radius: var(--border-radius-lg);
    overflow: hidden;
    position: relative;
}
.process-image img {
    width: 100%;
    height: auto;
    display: block;
}
.process-image-caption {
    position: absolute;
    bottom: 20px;
    left: 20px;
    background-color: rgba(255, 255, 255, 0.9);
    color: var(--color-dark-bg);
    padding: 8px 15px;
    border-radius: var(--border-radius-sm);
    display: flex;
    flex-direction: column;
    font-size: 0.9rem;
}
.process-image-caption .caption-name {
    font-weight: 600;
}
.process-image-caption .caption-role {
    font-size: 0.8rem;
    color: var(--color-text-dim);
}
.process-steps {
    flex: 1;
}
.step-item {
    margin-bottom: 40px;
    padding-left: 15px;
    border-left: 2px solid rgba(255, 255, 255, 0.1);
}
.step-item:last-child {
    margin-bottom: 0;
}
.step-item h4 {
    font-size: 1.4rem;
    font-weight: 700;
    margin-bottom: 10px;
    color: var(--color-secondary);
}
.step-item .step-number {
    color: var(--color-primary);
    margin-right: 15px;
    font-size: 1.8rem;
    font-weight: 800;
    opacity: 0.8;
}
.step-item p {
    color: var(--color-text-dim);
    margin-bottom: 15px;
}
.step-item ul {
    padding-left: 0;
}
.step-item ul li {
    color: var(--color-text-dim);
    margin-bottom: 5px;
}
.step-item ul li i {
    color: var(--color-secondary);
    margin-right: 10px;
}

/* ======================== TRUSTED BRANDS STYLES ========================== */
.boost-trusted-brands {
    padding-bottom: 0;
    padding-top: 100px;
}
.boost-trusted-brands .section-title {
    text-align: center;
    margin-bottom: 60px;
}
.boost-trusted-brands .section-title::after {
    margin: 10px auto 0;
}
.brands-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(180px, 1fr)); 
    gap: 20px; 
    align-items: center;
    justify-content: center;
}
.brand-logo {
    background-color: var(--color-dark-card);
    padding: 20px 10px; 
    border-radius: var(--border-radius-sm);
    display: flex;
    flex-direction: column; 
    align-items: center;
    justify-content: center;
    height: 100px; 
    font-weight: 600;
    font-size: 0.95rem;
    color: var(--color-text-dim);
    border: 1px solid rgba(255, 255, 255, 0.05);
    transition: transform 0.3s, box-shadow 0.3s, color 0.3s, border-color 0.3s;
}
.brand-logo i { 
    font-size: 1.8rem;
    color: var(--color-text-dim);
    margin-bottom: 8px;
    transition: color 0.3s;
}
.brand-logo span {
    font-weight: 500;
}
.brand-logo:hover {
    transform: translateY(-5px); 
    box-shadow: 0 5px 20px rgba(0, 210, 255, 0.4);
    color: var(--color-text-light);
    border-color: var(--color-primary);
}
.brand-logo:hover i {
    color: var(--color-secondary); 
}

/* ------------------- 3. CLIENTS SAY & BLOG ------------------- */
.boost-content-grid {
    display: grid; 
    grid-template-columns: 1fr 1fr;
    gap: 50px;
    padding-bottom: 100px;
}
.grid-item-col .section-title {
    margin-bottom: 40px;
}
/* Testimonials */
.testimonial-item {
    background-color: var(--color-dark-card);
    padding: 30px;
    border-radius: var(--border-radius-lg);
    border: 1px solid rgba(255, 255, 255, 0.08);
    margin-bottom: 20px; 
}
.testimonial-item p {
    color: var(--color-text-dim);
    font-style: italic;
    margin-bottom: 20px;
    line-height: 1.7;
}
.client-meta {
    display: flex;
    align-items: center;
}
.client-avatar {
    width: 40px;
    height: 40px;
    border-radius: 50%;
    background: linear-gradient(45deg, var(--color-secondary), var(--color-primary));
    color: white;
    font-size: 1.2rem;
    font-weight: bold;
    display: flex;
    align-items: center;
    justify-content: center;
    margin-right: 15px;
}
.client-details strong {
    display: block;
    font-size: 1rem;
    font-weight: 600;
}
.client-details small {
    color: var(--color-text-dim);
    font-size: 0.85rem;
}

/* ======================== BLOG INSIGHTS (ĐÃ SỬA LỖI HIỂN THỊ ẢNH) ========================== */
.blog-grid-small {
    display: grid;
    gap: 20px;
}
.blog-post-card {
    display: flex;
    background-color: var(--color-dark-card);
    padding: 15px;
    border-radius: var(--border-radius-sm);
    transition: background-color 0.3s;
    border: 1px solid rgba(255, 255, 255, 0.05);
}
.blog-post-card:hover {
    background-color: #26273b;
}
.blog-post-card img {
    width: 100px;
    height: 70px;
    object-fit: cover;
    border-radius: 5px;
    margin-right: 15px;
    flex-shrink: 0; /* KHẮC PHỤC LỖI: Giúp ảnh không bị co lại trong flexbox */
}
/* THÊM MỚI: Quy tắc này áp dụng nếu bạn dùng thẻ <div> làm placeholder ảnh/thumbnail */
.blog-post-card .blog-thumbnail-placeholder { 
    width: 100px;
    height: 70px;
    border-radius: 5px;
    margin-right: 15px;
    flex-shrink: 0; 
    background-color: #26273b; /* Nền tối cho placeholder */
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--color-secondary);
    font-weight: 600;
    font-size: 0.9rem;
    text-align: center;
    line-height: 1.2;
}
/* END THÊM MỚI */

.post-content {
    flex: 1;
}
.post-category {
    color: var(--color-secondary);
    font-size: 0.75rem;
    text-transform: uppercase;
    font-weight: 600;
    display: block;
    margin-bottom: 3px;
}
.blog-post-card h4 {
    font-size: 1rem;
    margin-bottom: 5px;
    line-height: 1.4;
}
.post-author-small {
    display: flex;
    align-items: center;
    font-size: 0.8rem;
    color: var(--color-text-dim);
    margin-bottom: 5px;
}
.author-avatar-small {
    width: 20px;
    height: 20px;
    border-radius: 50%;
    background: var(--color-primary);
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    font-size: 0.7rem;
    margin-right: 5px;
}
.read-more {
    font-size: 0.9rem;
    color: var(--color-primary);
}

/* ------------------- 4. PRE-FOOTER CTA ------------------- */
.boost-pre-footer-cta {
    background-color: #0b111a;
    padding: 100px 0;
    border-top: 1px solid rgba(255, 255, 255, 0.1);
}
.boost-pre-footer-cta h2 {
    font-size: 2.8rem;
    margin-bottom: 20px;
    font-weight: 800;
}
.boost-pre-footer-cta p {
    color: var(--color-text-dim);
    font-size: 1.1rem;
    margin-bottom: 40px;
}

/* ------------------- FOOTER ------------------- */
.boost-footer {
    padding-top: 60px;
    padding-bottom: 30px;
    background-color: #0c0c16;
}
.footer-grid {
    display: grid;
    grid-template-columns: 2fr 1fr 1fr 2fr;
    gap: 50px;
    padding-bottom: 40px;
}
.footer-col-1 p {
    margin: 15px 0 25px;
    color: var(--color-text-dim);
    max-width: 300px;
}
.footer-col h4 {
    margin-bottom: 20px;
    color: var(--color-text-light);
    font-weight: 600;
}
.footer-col ul {
    list-style: none;
}
.footer-col ul li {
    margin-bottom: 10px;
}
.footer-col a, .footer-col address {
    color: var(--color-text-dim);
    line-height: 1.8;
}
.social-icons a {
    font-size: 1.2rem;
    margin-right: 15px;
    color: var(--color-text-dim);
}
.social-icons a:hover {
    color: var(--color-primary);
}
.copyright {
    padding-top: 20px;
    border-top: 1px solid rgba(255, 255, 255, 0.05);
    color: var(--color-text-dim);
    font-size: 0.9rem;
    display: flex;
    justify-content: space-between;
}


/* ===================================================================== */
/* ======================== RESPONSIVE DESIGN ========================== */
/* ===================================================================== */

/* --- 1. Tablet (Màn hình từ 992px trở xuống) --- */
@media (max-width: 992px) {
    .section-padding {
        padding-top: 60px;
        padding-bottom: 60px;
    }
    .boost-header {
        padding: 15px 20px;
    }
    .boost-nav {
        display: none; /* Ẩn menu nav trên tablet, cần dùng JS/hambuger menu */
    }
    .boost-hero h1 {
        font-size: 3rem;
    }
    .boost-stats {
        gap: 40px;
    }

    /* 1. About Us: Chuyển sang xếp chồng */
    .boost-about-us {
        flex-direction: column;
        padding-bottom: 60px;
    }
    .boost-about-us .about-visual {
        margin-top: 40px;
    }
    .boost-about-us .stats-card {
        min-width: 100%; /* Mở rộng hết chiều rộng */
    }

    /* 2. Process: Chuyển sang xếp chồng */
    .process-container {
        flex-direction: column;
    }
    .boost-process {
        padding: 50px 30px;
    }
    .process-image {
        order: -1; /* Đẩy ảnh lên trên */
    }

    /* 3. Client Say & Blog: Chuyển sang xếp chồng */
    .boost-content-grid {
        grid-template-columns: 1fr;
        gap: 30px;
    }
    
    /* Footer: 2 cột */
    .footer-grid {
        grid-template-columns: 1fr 1fr;
    }
    .footer-col-1 {
        grid-column: span 2; /* Chiếm 2 cột */
        margin-bottom: 20px;
    }
}

/* --- 2. Mobile (Màn hình từ 600px trở xuống) --- */
@media (max-width: 600px) {
    .section-title {
        font-size: 2rem;
    }
    .boost-hero {
        padding-top: 100px;
        padding-bottom: 80px;
    }
    .boost-hero h1 {
        font-size: 2.2rem;
    }
    .hero-buttons {
        display: flex;
        flex-direction: column;
        gap: 15px;
    }
    .boost-btn-secondary, .boost-btn-outline {
        margin-right: 0;
    }

    /* Stats: Chuyển sang xếp chồng ngang cuộn */
    .boost-stats {
        display: grid;
        grid-template-columns: 1fr 1fr 1fr;
        gap: 20px;
        margin-top: 40px;
    }
    .boost-stats > div {
        padding: 10px;
    }

    /* About Us: Thẻ stats 1 cột */
    .boost-about-us .stats-card {
        grid-template-columns: 1fr;
        padding: 20px;
    }
    .boost-about-us .stat-item:nth-child(3) {
        grid-column: span 1;
    }

    /* Brands: Lưới 2 cột */
    .brands-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    .brand-logo {
        height: 80px;
        padding: 10px;
        font-size: 0.85rem;
    }
    .brand-logo i {
        font-size: 1.5rem;
        margin-bottom: 4px;
    }

    /* Blog: Khắc phục lỗi hiển thị ảnh trên Mobile */
    .blog-post-card img {
        width: 80px;
        height: 50px;
        margin-right: 10px;
    }
    .blog-post-card .blog-thumbnail-placeholder {
        width: 80px;
        height: 50px;
        margin-right: 10px;
    }
    
    /* Footer: 1 cột */
    .footer-grid {
        grid-template-columns: 1fr;
        gap: 30px;
        text-align: center;
    }
    .footer-col-1 {
        grid-column: span 1;
        text-align: center;
    }
    .footer-col-1 .boost-logo {
        width: 100%;
    }
    .footer-col-1 p {
        margin-left: auto;
        margin-right: auto;
    }
    .copyright {
        flex-direction: column;
        align-items: center;
        text-align: center;
    }
    .designed-by {
        margin-top: 5px;
    }
}