:root{
  --bg:#f7f7fb;
  --text:#0b1220;
  --accent:#3b82f6;
  --muted:#6b7280;
}
*{box-sizing:border-box}
body{
  margin:0;
  font-family:Inter, system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial;
  background:var(--bg);
  color:var(--text);
  line-height:1.5;
}
.container{max-width:720px;margin:2rem auto;padding:0 1rem}
.site-header{background:white;padding:1.25rem 0;display:flex;align-items:center;justify-content:center;gap:.75rem;box-shadow:0 1px 0 rgba(11,18,32,0.04);position:relative}
.hero{padding:2rem 0;text-align:center}
.btn{display:inline-block;background:var(--accent);color:white;padding:.6rem 1rem;border-radius:6px;text-decoration:none}
.contact form{display:flex;gap:.5rem}
.contact input{flex:1;padding:.6rem;border:1px solid #ddd;border-radius:6px}
.contact button{padding:.6rem 1rem;border-radius:6px;border:none;background:var(--accent);color:#fff}

.site-logo{height:56px;max-height:64px;width:auto;display:block}
.visually-hidden{position:absolute;width:1px;height:1px;padding:0;margin:-1px;overflow:hidden;clip:rect(0 0 0 0);white-space:nowrap;border:0}

.brand-wrap{display:flex;align-items:center;gap:.5rem}
.brand-divider{width:1px;height:32px;background:#f1f2f6;display:inline-block;border-radius:1px}
.brand-text{font-weight:500;font-size:1.12rem;color:var(--muted);font-family:Inter, system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial;letter-spacing:.04em;white-space:nowrap}

/* Header B-BAE brand (replaces NEU logo + text on B-BAE page) */
.bbae-brand{display:inline-flex;align-items:center;gap:.06rem;text-decoration:none;padding:.05rem .25rem}
.bbae-brand .bbae-first{color:#0148ca;font-weight:700;font-style:italic;font-size:clamp(28px,6vw,64px);line-height:1}
.bbae-dash{color:#eb5227;display:inline-block;font-weight:700;font-style:italic;font-size:clamp(34px,7vw,76px);line-height:1;vertical-align:baseline;margin:0 .02rem;transform:translateY(-0.12em);}
.bbae-brand .bbae-rest{color:#eb5227;font-weight:700;font-style:italic;font-size:clamp(28px,6vw,64px);line-height:1}

/* Canvas area for blank content */
.canvas{padding:1.5rem 1rem}
.canvas-inner{max-width:880px;margin:0 auto;text-align:center}
.canvas-title{color:#eb5227;font-weight:700;font-style:italic;font-size:clamp(36px,6vw,96px);margin:0;padding-top:.5rem;letter-spacing:.02em}
.canvas-title .accent-b{color:#0148ca}

/* Q&A */
.qa-container{margin-top:3.25rem;display:flex;flex-direction:column;align-items:center}
.qa-toggle{width:100%;max-width:720px;background:transparent;border:1px solid transparent;display:flex;align-items:center;justify-content:space-between;padding:1rem 1.25rem;border-radius:8px;cursor:pointer;font-size:1.05rem;color:var(--text);text-align:left}
.qa-toggle:hover{background:rgba(0,0,0,0.02)}
.qa-toggle:focus{outline:2px solid rgba(3,102,214,0.12);outline-offset:2px}
.qa-question{font-weight:500;font-size:1.15rem}
.qa-arrow{transition:transform .2s ease;color:var(--muted);font-size:1.25rem}
.qa-toggle.open .qa-arrow{transform:rotate(90deg)}
.qa-content{max-height:0;overflow:hidden;transition:max-height .28s ease;max-width:720px;margin:0 auto;padding:0 1rem}
.qa-content p{margin:0;padding:1rem 0;color:var(--muted);line-height:1.45}

/* B-BAE clickable link */
.bb-link{background:transparent;border:none;padding:0;color:inherit;font:inherit;cursor:pointer;text-decoration:none}
.bb-link:hover{text-decoration:none}
.bb-link:focus{outline:2px solid rgba(1,72,202,0.15);outline-offset:3px}
/* Homepage B-BAE spacing: always visible */
.bb-home{
  margin-top:3.5rem;
  text-align:center;
  opacity:1;
  transform:none;
  transition:none;
  pointer-events:auto;
}

/* Modal */
.modal{position:fixed;inset:0;display:none;align-items:center;justify-content:center;background:rgba(3,6,23,0.45);z-index:60}
.modal.open{display:flex}
.modal-panel{background:#fff;border-radius:10px;box-shadow:0 10px 30px rgba(11,18,32,0.12);width:min(92vw,980px);max-height:86vh;overflow:hidden;display:flex;flex-direction:column}
.modal-header{display:flex;align-items:center;justify-content:space-between;padding:1rem 1.25rem;border-bottom:1px solid #eef0f4}
.modal-header h3{margin:0;font-size:1.15rem}
.modal-close{background:transparent;border:none;font-size:1.25rem;cursor:pointer}
.modal-body{display:flex;gap:1rem;padding:1rem;overflow:auto}

/* File viewer page layout: keep the file list and viewer side-by-side
   so the viewer never overlaps or 'eats into' the file list text. */
.bb-page-grid{display:grid;grid-template-columns:260px 1fr;gap:2rem;align-items:start;padding-top:.5rem}
.bb-left{width:auto;min-width:220px}
.bb-right{overflow:visible}

@media (max-width:720px){
  .bb-page-grid{grid-template-columns:1fr}
  .bb-left{min-width:0;width:100%;border-right:none;padding-right:0}
  .bb-right{width:100%;padding-left:0}
}
.bb-left{width:40%;min-width:220px;border-right:1px solid #f1f2f5;padding-right:1rem}
.bb-left h4{margin:.4rem 0;font-size:clamp(1.1rem,2.2vw,1.4rem);font-weight:600}
.bb-left h4 a.bb-year{color:var(--text);text-decoration:none;font-weight:700;font-size:inherit}
.bb-left h4 a.bb-year:hover{text-decoration:underline}
.bb-left h5{margin:.4rem 0 .2rem;font-size:.9rem;color:var(--muted)}
.bb-left ul{list-style:none;padding-left:0;margin:0}
.bb-left li{margin:.25rem 0}
.bb-file{color:var(--accent);text-decoration:none}
.bb-file:hover{text-decoration:underline}
.bb-right{flex:1;display:flex;flex-direction:column;align-items:center;justify-content:center;padding-left:1rem}
.bb-right img{max-width:100%;height:auto;max-height:68vh;object-fit:contain;border-radius:6px;display:block;margin:0 auto}
.bb-viewer-caption{color:var(--muted);font-size:.95rem;margin-top:.5rem}

/* Rotate images marked as rotated-right */
.bb-right img.bb-rotated-right{transform:rotate(90deg);transform-origin:center center;max-width:68vh;max-height:100%;object-fit:contain;display:block;margin:0 auto}
.bb-lb-panel img.bb-rotated-right{transform:rotate(90deg);transform-origin:center center;max-width:80vh;max-height:80vw;object-fit:contain;display:block;margin:0 auto}

/* Year grid (3x3 tiles) */
.year-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:1rem;max-width:980px;margin:2rem auto;padding:0 1rem}
.year-tile{background:#fff;border-radius:10px;box-shadow:0 8px 24px rgba(11,18,32,0.06);padding:1.25rem 1rem;display:flex;flex-direction:column;align-items:center;justify-content:center;text-decoration:none;color:var(--text);min-height:120px}
.year-tile:hover{transform:translateY(-6px);box-shadow:0 18px 40px rgba(11,18,32,0.08)}
.year-tile:active{transform:translateY(-2px)}
.year-title{font-size:1.35rem;font-weight:700}
.year-sub{font-size:.95rem;color:var(--muted);margin-top:.25rem}
.year-tile.empty{opacity:.8}
.year-tile.placeholder{background:transparent;box-shadow:none;border:1px dashed #eef0f4;min-height:120px}

@media (max-width:900px){
  .year-grid{grid-template-columns:repeat(2,1fr)}
}
@media (max-width:480px){
  .year-grid{grid-template-columns:repeat(1,1fr)}
}

/* Mobile-only: enlarge B-BAE on homepage */
@media (max-width:480px) {
  .bb-home{
    font-size:clamp(80px,20vw,220px);
    line-height:1;
    padding-top:.25rem;
    margin-bottom:1.25rem;
  }
  .bb-home .accent-b{color:#0148ca}
  .bb-home .bbae-dash{color:#eb5227}
  .bb-home .bbae-dash{font-size:1em;display:inline-block;vertical-align:middle;transform:translateY(-0.12em);line-height:1}
  /* Limit inline viewer image on mobile to avoid overly large images */
  .bb-right{margin-top:1.5rem;padding-top:0.5rem}
  .bb-right img{max-height:40vh;max-width:86%;width:auto;border-radius:8px;display:block;margin:0.6rem auto}
  .bb-right img.bb-rotated-right{max-width:40vh;max-height:none}
}

/* Also enlarge B-BAE on the B-BAE year selector page for mobile */
@media (max-width:480px) {
  .bb-brand--header .bbae-brand .bbae-first,
  .bb-brand--header .bbae-brand .bbae-rest{font-size:clamp(72px,18vw,220px);line-height:1}
  .bb-brand--header .bbae-brand .bbae-dash{font-size:clamp(78px,20vw,240px)}
}

@media (max-width:720px){
  .modal-body{flex-direction:column}
  .bb-left{width:100%;border-right:none;padding-right:0}
  .bb-right{width:100%;padding-left:0}
}

@media (max-width:480px){
  /* compact header on small screens */
}

/* Lightbox for Năm pages */
.bb-lightbox{position:fixed;inset:0;display:none;align-items:center;justify-content:center;background:rgba(0,0,0,0.75);z-index:120}
.bb-lightbox.open{display:flex}
.bb-lb-panel{position:relative;max-width:90%;max-height:90%;display:flex;align-items:center;justify-content:center}
.bb-lb-panel img{max-width:100%;max-height:80vh;object-fit:contain;border-radius:6px;background:#fff}
.bb-lb-close{position:absolute;top:-8px;right:-8px;background:rgba(255,255,255,0.95);border:none;border-radius:6px;padding:6px;cursor:pointer}
.bb-lb-prev,.bb-lb-next{position:absolute;top:50%;transform:translateY(-50%);background:rgba(255,255,255,0.95);border:none;border-radius:6px;padding:8px 10px;font-size:18px;cursor:pointer}
.bb-lb-prev{left:-60px}
.bb-lb-next{right:-60px}
.bb-lb-caption{margin-top:.5rem;color:var(--muted)}
@media (max-width:720px){
  .bb-lb-prev{left:8px}
  .bb-lb-next{right:8px}
}

/* viewer states */
.bb-right img.bb-img-loading{opacity:.35;transition:opacity .2s ease}
.bb-right img.bb-img-error{opacity:.6;filter:grayscale(1);border:1px dashed #e6e7eb}