/* --- CÀI ĐẶT CƠ BẢN & PHÔNG CHỮ --- */
body {
    font-family: 'Mulish', sans-serif;
    color: #cbd5e1;
    line-height: 1.8;
    background-color: #0f172a;
    margin: 0;
    font-size: 1.125rem;
    overflow-x: hidden;
    padding-top: 45px;
    padding-bottom: 150px; 
}

h1, h2, h3 { font-family: 'Playfair Display', serif; }

.retro-title {
    font-family: 'Oswald', sans-serif;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    line-height: 1.1;
}

.article-container {
    max-width: 56rem;
    margin: 0 auto;
    padding: 0 1.5rem;
}

/* --- HEADER CỐ ĐỊNH --- */
.sp-sticky-header {
    position: fixed; top: 0; left: 0; width: 100%; height: 45px;
    background-color: rgba(0,0,0,0.95); display: flex; align-items: center; justify-content: space-between;
    z-index: 99999; border-bottom: 1px solid #333; backdrop-filter: blur(10px);
}

.left-group, .right-group { display: flex; align-items: center; height: 100%; }
.left-group { padding-left: 10px; }
.right-group { padding-right: 10px; }

.sp-back-to-home {
    display: flex; align-items: center; justify-content: center; width: 45px; height: 45px;
    background-color: #007f74; color: white; text-decoration: none; font-size: 18px;
    transition: 0.3s;
}
.sp-back-to-home:hover { background-color: #00a89a; }

.sp-mag-logo { margin-left: 15px; }
.sp-mag-logo img { height: 22px; width: auto; filter: brightness(0) invert(1); }

.center-logo { position: absolute; left: 50%; transform: translateX(-50%); }
.center-logo img { height: 24px; width: auto; opacity: 0.8; }

.fb-custom-btn {
    display: flex; align-items: center; gap: 6px; color: #ccc;
    text-decoration: none; font-size: 12px; font-weight: bold; 
    padding: 5px 12px; border: 1px solid #444; border-radius: 4px; transition: 0.2s;
}
.fb-custom-btn:hover { color: white; border-color: white; }

/* --- HERO SECTION --- */
.hero-parallax {
    width: 100vw; height: 100vh; position: relative; left: 50%; right: 50%;
    margin-left: -50vw; margin-right: -50vw; background-attachment: fixed;
    background-position: center; background-repeat: no-repeat; background-size: cover;
    display: flex; align-items: center; justify-content: center;
    background-image: url('https://sohanews.sohacdn.com/160588918557773824/2026/1/31/le-khanh-thanh-truong-si-pa-phin-9-17698739715022105360629.jpg');
}

.hero-gradient {
    position: absolute; inset: 0;
    background: linear-gradient(to top, #0f172a 0%, rgba(15, 23, 42, 0.4) 40%, transparent 100%);
}

.hero-content { position: relative; z-index: 10; text-align: center; padding: 0 1.5rem; animation: slideUpFade 1.2s forwards; }
.hero-title { font-size: 3.5rem; font-weight: 700; color: white; text-shadow: 0 2px 10px rgba(0,0,0,0.5); }
.gold-text { color: #fbbf24; }

/* --- CONTENT UI --- */
.drop-cap-text::first-letter {
    float: left; font-size: 4rem; line-height: 0.8; padding: 4px 12px 0 0;
    color: #fbbf24; font-family: 'Playfair Display', serif; font-weight: 700;
}

.section-heading {
    font-size: 2rem; font-weight: 700; margin: 3rem 0 2.5rem; text-align: center;
    color: #fbbf24; text-shadow: 0 2px 4px rgba(0,0,0,0.5);
}

.rich-article-text p { margin-bottom: 1.5rem; text-align: justify; }

.parallax-scroll-img {
    width: 100vw; height: 80vh; position: relative; left: 50%; right: 50%;
    margin: 4rem -50vw; background-attachment: fixed; background-position: center;
    background-repeat: no-repeat; background-size: cover; cursor: pointer;
}

.drone-img { background-image: url('https://sohanews.sohacdn.com/160588918557773824/2026/1/31/le-khanh-thanh-truong-si-pa-phin-5-17698739714902060204501.jpg'); }
.campus-img { background-image: url('https://sohanews.sohacdn.com/160588918557773824/2026/1/31/le-khanh-thanh-truong-si-pa-phin-10-17698739715141600560846.jpg'); }
.build-img { background-image: url('https://sohanews.sohacdn.com/160588918557773824/2026/1/31/toan-canh-truong-si-pa-phin-17698761379711895300794.jpg'); }
.ceremony-img { background-image: url('https://sohanews.sohacdn.com/160588918557773824/2026/1/31/untitled-03-17698411816061665888737.jpg'); }

/* SLIDER */
.full-width-slider-wrapper {
    width: 100vw; position: relative; left: 50%; right: 50%; margin: 3rem -50vw;
    background: #1e293b; padding: 2rem 0;
}
.slider-container { display: flex; overflow-x: auto; scroll-snap-type: x mandatory; gap: 8px; padding: 0 1rem; }
.slider-item { flex: 0 0 85%; scroll-snap-align: center; height: 400px; cursor: zoom-in; }
.slider-img { width: 100%; height: 100%; object-fit: cover; }

/* QUOTES */
.magazine-quote { border-left: 3px solid #ca8a04; padding-left: 1.5rem; margin: 2rem 0; font-style: italic; color: #e2e8f0; }
.magazine-quote p { font-family: 'Playfair Display', serif; font-size: 1.25rem; margin-bottom: 0.5rem; }
.magazine-quote footer { font-family: 'Mulish', sans-serif; font-size: 0.9rem; color: #fbbf24; font-weight: 600; text-transform: uppercase; }

.parallax-full-quote {
    width: 100vw; min-height: 500px; position: relative; left: 50%; right: 50%; margin: 4rem -50vw;
    background-image: url('https://sohanews.sohacdn.com/160588918557773824/2026/1/31/le-khanh-thanh-truong-si-pa-phin-2-17698739714811670263791.jpg');
    background-attachment: fixed; background-size: cover; background-position: center;
    display: flex; align-items: center; justify-content: center; text-align: center;
}
.quote-overlay-dark { position: absolute; inset: 0; background: rgba(0,0,0,0.6); }
.quote-container { position: relative; z-index: 10; max-width: 800px; padding: 0 20px; }
.quote-symbol { display: block; font-size: 4rem; color: #fbbf24; line-height: 1; opacity: 0.8; margin-bottom: 10px; font-family: serif; }
.quote-content-text { font-family: 'Playfair Display', serif; font-size: 1.25rem; font-style: italic; color: white; margin-bottom: 2rem; }
.quote-author-info .name { color: #fbbf24; font-weight: 700; text-transform: uppercase; margin: 0; }
.quote-author-info .title { color: #cbd5e1; font-size: 0.85rem; text-transform: uppercase; margin-top: 5px; }

/* --- FLIP CARDS --- */
.data-parallax-section {
    width: 100vw; position: relative; left: 50%; right: 50%; margin: 4rem -50vw 0;
    background-image: url('https://sohanews.sohacdn.com/160588918557773824/2026/1/31/dsc03736-176983773756610019999.jpg');
    background-attachment: fixed; background-size: cover; background-position: center; padding: 60px 1.5rem;
}
.data-parallax-section::before { content: ''; position: absolute; inset: 0; background: rgba(15, 23, 42, 0.85); z-index: 0; }
.data-wrapper { position: relative; z-index: 10; max-width: 1100px; margin: 0 auto; }
.data-grid-container { display: grid; grid-template-columns: repeat(auto-fit, minmax(200px, 1fr)); gap: 20px; }

.flip-card { perspective: 1000px; height: 280px; cursor: pointer; }
.card-inner-box { position: relative; width: 100%; height: 100%; transform-style: preserve-3d; transition: 0.8s; }
.flip-card:hover .card-inner-box, .flip-card.active .card-inner-box { transform: rotateY(180deg); }

.card-face-front, .card-face-back { 
    position: absolute; inset: 0; border-radius: 12px; padding: 20px; 
    backface-visibility: hidden; display: flex; flex-direction: column; 
    align-items: center; justify-content: center; box-shadow: 0 10px 15px -3px rgba(0,0,0,0.3);
}
.card-face-front { background: rgba(30, 41, 59, 0.7); border: 1px solid rgba(251, 191, 36, 0.3); backdrop-filter: blur(5px); }
.card-icon { font-size: 32px; margin-bottom: 10px; }
.card-num { font-family: 'Oswald', sans-serif; font-size: 3rem; font-weight: 700; color: #fbbf24; line-height: 1; text-align: center; }
.card-unit { font-size: 0.9rem; text-transform: uppercase; letter-spacing: 0.05em; color: #cbd5e1; font-weight: 600; margin-top: 5px; }
.card-tap { margin-top: auto; font-size: 0.75rem; color: #94a3b8; opacity: 0.8; }
.card-face-back { background: #1e293b; transform: rotateY(180deg); text-align: center; border: 1px solid rgba(255, 255, 255, 0.1); }
.card-face-back strong { display: block; font-family: 'Playfair Display', serif; font-size: 1.2rem; color: #fbbf24; margin-bottom: 10px; border-bottom: 1px solid rgba(251, 191, 36, 0.3); width: 100%; padding-bottom: 5px; }
.card-face-back p { font-size: 0.9rem; color: #e2e8f0; line-height: 1.5; margin: 0; }

/* --- LIGHTBOX --- */
#lightbox { display: none; position: fixed; z-index: 9999; inset: 0; background: rgba(0,0,0,0.95); align-items: center; justify-content: center; flex-direction: column; }
#lightbox img { max-width: 90%; max-height: 85vh; object-fit: contain; border: 2px solid #333; }
#lightbox-caption { color: #ccc; margin-top: 15px; font-family: 'Mulish', sans-serif; }
#close-btn { position: absolute; top: 20px; right: 30px; color: white; font-size: 40px; cursor: pointer; font-weight: bold; }

/* --- FOOTER --- */
.sp-footer { background-color: #061224; padding: 30px 20px; border-top: 1px solid #1e293b; color: #e2e8f0; text-align: center; }
.footer-inner { max-width: 1200px; margin: 0 auto; display: flex; justify-content: center; align-items: center; flex-wrap: wrap; gap: 10px 40px; }
.copyright { opacity: 0.6; font-size: 13px; margin: 0; }

@keyframes slideUpFade { from { opacity: 0; transform: translateY(60px); } to { opacity: 1; transform: translateY(0); } }

@media (max-width: 768px) {
    .hero-title { font-size: 2.2rem; }
    .hero-parallax, .parallax-scroll-img, .data-parallax-section, .parallax-full-quote { background-attachment: scroll !important; }
    .center-logo { display: none; }
    .data-grid-container { grid-template-columns: repeat(2, 1fr); }
    .flip-card:last-child:nth-child(odd) { grid-column: span 2; width: 60%; margin: 0 auto; }
    .hero-parallax { background-image: url('https://sohanews.sohacdn.com/160588918557773824/2026/1/31/mobicover-17698518705501869619530.png'); }
}
@media (min-width: 769px) { .slider-item { flex: 0 0 60%; } }