/* =========================================
   1. GIAO DIỆN CHUNG (DESKTOP)
   ========================================= */

.mss-scroll-container {
    max-width: 100%;
    margin: 0 auto;
    padding: 0; 
    position: relative;
    overflow: visible; 
    background-color: transparent; 
}

/* Khối Item */
.mss-stack-item {
    position: -webkit-sticky;
    position: sticky;
    
    top: var(--mss-top, 20vh);
    min-height: var(--mss-min-height, 600px);
    background-color: var(--mss-bg-color, #000);
    
    width: 100%;
    display: flex;
    flex-direction: column;
    
    margin-bottom: 30px; 
    
    border-radius: 0 !important; 
    overflow: hidden;
    box-shadow: none;
    z-index: 1;

    /* === CẤU HÌNH HIỆU ỨNG === */
    transform-origin: center top;
    transition: transform 0.1s linear, filter 0.1s linear;
    will-change: transform, filter;
    
    transform: scale(1);
    filter: brightness(1);
}

.mss-stack-item:last-child {
    min-height: auto !important;
    height: auto !important;
    margin-bottom: 0 !important;
}

.mss-stack-inner {
    display: flex; 
    flex-wrap: wrap;
    width: 100%;
    flex-grow: 1; 
    min-height: 100%;
}

.mss-content-col {
    flex: 1; 
    flex-basis: 50%;
    padding: 60px; 
    display: flex;
    flex-direction: column;
    justify-content: space-between; 
    box-sizing: border-box;
    min-width: 300px; 
}

.mss-text-wrapper {
    display: flex;
    flex-direction: column;
    align-items: flex-start;
    justify-content: center;
    flex-grow: 1;
    padding-bottom: 40px; 
}

.mss-title {
    font-weight: 700;
    line-height: 1.1;
    margin: 0 0 24px 0;
    word-break: break-word;
    color: var(--mss-title-color, #fff);
    font-size: var(--mss-title-size, 56px);
}

.mss-desc {
    line-height: 1.6;
    margin-bottom: 40px;
    opacity: 0.9;
    max-width: 100%;
    color: var(--mss-desc-color, #ccc);
    font-size: var(--mss-desc-size, 18px);
}

.mss-btn {
    display: inline-block;
    padding: 0 0 8px 0;
    border-radius: 0;
    text-decoration: none;
    font-weight: 600;
    transition: all 0.3s ease;
    margin-top: auto;
    border-bottom: 1px solid rgba(255, 255, 255, 0.3);
    background-color: transparent !important;
    border-bottom-color: currentColor; 
    opacity: 0.8;
    color: var(--mss-btn-color, #fff);
    font-size: var(--mss-btn-size, 16px);
}
.mss-btn:hover { opacity: 1; }

.mss-number {
    font-weight: 700;
    line-height: 1;
    opacity: 1; 
    font-family: sans-serif;
    margin-top: 20px;
    color: var(--mss-number-color, #333);
    font-size: var(--mss-number-size, 100px);
}

.mss-image-col {
    flex: 1; 
    flex-basis: 50%;
    position: relative;
    display: flex; 
    min-height: 100%; 
}

.mss-image-col img {
    width: 100%;
    height: 100%;
    object-fit: cover; 
    display: block;
    position: absolute; 
    top: 0;
    left: 0;
}

.mss-stack-inner.mss-layout-left {
    flex-direction: row-reverse;
}

/* =========================================
   2. GIAO DIỆN MOBILE (Dưới 991px)
   ========================================= */
@media (max-width: 991px) {
    .mss-scroll-container {
        width: 100% !important; 
        padding: 40px 0;
        background-color: transparent; 
    }

    .mss-stack-item {
        position: relative !important;
        top: 0 !important;
        min-height: auto !important;
        height: auto !important;
        margin-bottom: 20px;
        display: block; 
        
        transform: none !important;
        filter: none !important;
        border-radius: 0 !important;
    }
    
    .mss-stack-inner,
    .mss-stack-inner.mss-layout-left {
        display: flex;
        flex-direction: column; 
    }

    .mss-content-col {
        width: 100%;
        padding: 30px 20px;
        display: flex;
        flex-direction: column;
        justify-content: flex-start;
        align-items: flex-start;
    }
    
    .mss-text-wrapper {
        padding-bottom: 0;
        width: 100%;
        order: 2; /* Text nằm dưới Số */
    }

    .mss-number {
        order: 1; /* Số nằm trên cùng */
        width: 100%;
        text-align: left;
        margin-top: 0;
        
        /* [REQ 1] Tăng khoảng cách với tiêu đề bên dưới lên 50px */
        margin-bottom: 50px; 
    }

    .mss-image-col {
        width: 100%;
        height: 220px; 
        display: block;
        position: relative;
        flex: none;
        order: 3; 
    }
    
    .mss-title { 
        margin-bottom: 15px;
        
        /* [REQ 2] Giảm font size Mobile còn 40px */
        font-size: 25px !important; 
    }
    
    .mss-desc { margin-bottom: 25px; }
}