/* ========================================
   HYPERPHYSICS.COM — CPP PAPERS STYLESHEET
   Dark scientific aesthetic, gold/blue accents
   Based on the Electroweak Series template
   ======================================== */

/* Reset & Variables */
*,*::before,*::after{margin:0;padding:0;box-sizing:border-box}
:root{
  --bg-primary:#0a0e14;
  --bg-secondary:#0d1117;
  --bg-card:#111820;
  --bg-card-hover:#151d28;
  --border-subtle:rgba(184,134,11,.15);
  --border-gold:rgba(184,134,11,.35);
  --gold:#DAA520;
  --gold-dim:#B8860B;
  --gold-glow:rgba(218,165,32,.15);
  --blue:#4A9BD9;
  --blue-dim:#2E6EA6;
  --blue-glow:rgba(74,155,217,.1);
  --text-primary:#E8E2D6;
  --text-secondary:#9CA3AF;
  --text-muted:#6B7280;
  --accent-red:#D4574E;
  --accent-green:#4ADE80;
  --serif:'Cormorant Garamond','Georgia',serif;
  --body:'Crimson Pro','Georgia',serif;
  --mono:'JetBrains Mono',monospace;
  --sidebar-w:280px;
  --transition-fast:.2s ease;
  --transition-med:.35s ease;
}

html{scroll-behavior:smooth}
body{
  font-family:var(--body);
  color:var(--text-primary);
  line-height:1.7;
  background:var(--bg-primary);
  overflow-x:hidden;
  min-height:100vh;
}

/* Typography */
h1,h2,h3,h4{font-family:var(--serif);font-weight:600;line-height:1.25}
h1{font-size:2rem;color:var(--text-primary);letter-spacing:.02em}
h2{font-size:1.5rem;color:var(--gold);letter-spacing:.03em;margin-bottom:1rem;padding-bottom:.5rem;border-bottom:1px solid var(--border-subtle)}
h3{font-size:1.15rem;color:var(--blue);margin-bottom:.75rem}
p{margin-bottom:1rem;color:var(--text-secondary)}
a{color:var(--gold);text-decoration:none;transition:color var(--transition-fast)}
a:hover{color:var(--blue)}
code{font-family:var(--mono);font-size:.85em;background:rgba(255,255,255,.05);padding:.15em .4em;border-radius:3px}

/* ========== TOP NAV ========== */
.top-nav{
  position:fixed;top:0;left:0;right:0;z-index:200;
  height:56px;display:flex;align-items:center;justify-content:space-between;
  padding:0 1.5rem;
  background:rgba(10,14,20,.92);
  backdrop-filter:blur(20px);-webkit-backdrop-filter:blur(20px);
  border-bottom:1px solid var(--border-subtle);
}
.nav-brand{font-family:var(--serif);font-size:1.2rem;font-weight:600;color:var(--text-primary);text-decoration:none;letter-spacing:.06em;text-transform:uppercase}
.nav-brand span{color:var(--gold)}
.nav-links{display:flex;gap:.25rem;list-style:none;align-items:center}
.nav-links li a{color:var(--text-secondary);text-decoration:none;font-family:var(--serif);font-size:.9rem;padding:.4rem .7rem;border-radius:3px;transition:all var(--transition-fast)}
.nav-links li a:hover,.nav-links li a.active{color:var(--gold);background:var(--gold-glow)}
.nav-links .dropdown{position:relative}
.nav-links .dropdown-menu{display:none;position:absolute;top:100%;left:0;background:rgba(13,17,23,.97);backdrop-filter:blur(16px);border:1px solid var(--border-subtle);border-radius:4px;min-width:240px;padding:.5rem 0;z-index:300}
.nav-links .dropdown:hover .dropdown-menu{display:block}
.dropdown-menu a{display:block;padding:.45rem 1.2rem;color:var(--text-secondary);font-size:.88rem;transition:all var(--transition-fast)}
.dropdown-menu a:hover{background:var(--gold-glow);color:var(--gold)}
.hamburger{display:none;flex-direction:column;gap:5px;cursor:pointer;padding:4px;background:none;border:none}
.hamburger span{width:22px;height:2px;background:var(--text-primary);transition:var(--transition-fast)}

/* ========== SIDEBAR ========== */
.sidebar{
  position:fixed;top:56px;left:0;bottom:0;width:var(--sidebar-w);
  background:var(--bg-secondary);border-right:1px solid var(--border-subtle);
  overflow-y:auto;padding:1.5rem 0;z-index:100;
  transition:transform var(--transition-med);
}
.sidebar-header{padding:0 1.25rem 1.25rem;border-bottom:1px solid var(--border-subtle);margin-bottom:1rem}
.sidebar-title{font-family:var(--serif);font-size:1.1rem;font-weight:600;color:var(--gold);letter-spacing:.04em}
.sidebar-subtitle{font-size:.78rem;color:var(--text-muted);margin-top:.2rem;font-family:var(--mono);letter-spacing:.06em;text-transform:uppercase}
.sidebar-section{padding:.5rem 0}
.sidebar-section-title{font-family:var(--mono);font-size:.68rem;letter-spacing:.12em;text-transform:uppercase;color:var(--text-muted);padding:.5rem 1.25rem;margin-bottom:.25rem}
.sidebar-link{display:block;padding:.45rem 1.25rem;color:var(--text-secondary);font-size:.88rem;transition:all var(--transition-fast);border-left:2px solid transparent;text-decoration:none}
.sidebar-link:hover{color:var(--gold);background:var(--gold-glow);border-left-color:var(--gold-dim)}
.sidebar-link.active{color:var(--gold);border-left-color:var(--gold);background:var(--gold-glow);font-weight:500}
.sidebar-link .paper-num{font-family:var(--mono);font-size:.72rem;color:var(--text-muted);margin-right:.35rem}

/* ========== MAIN CONTENT ========== */
.main-content{margin-left:var(--sidebar-w);padding:56px 0 0;min-height:100vh}
.content-wrap{max-width:900px;margin:0 auto;padding:2.5rem 2rem 4rem}

/* Page Header */
.page-header{margin-bottom:2.5rem;padding-bottom:2rem;border-bottom:1px solid var(--border-subtle)}
.series-badge{display:inline-block;font-family:var(--mono);font-size:.72rem;letter-spacing:.1em;text-transform:uppercase;color:var(--gold);background:var(--gold-glow);padding:.3rem .8rem;border-radius:2px;border:1px solid var(--border-gold);margin-bottom:1rem}
.page-title{font-size:1.8rem;color:var(--text-primary);margin-bottom:.75rem;line-height:1.3}
.page-subtitle{font-size:1.05rem;color:var(--text-secondary);line-height:1.6;max-width:700px}
.page-meta{margin-top:1.25rem;display:flex;flex-wrap:wrap;gap:.5rem 1.5rem;font-size:.85rem;color:var(--text-muted)}
.page-meta strong{color:var(--text-secondary)}

/* Content Sections */
.content-section{margin-bottom:2.5rem}

/* Key Results Cards */
.results-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(200px,1fr));gap:1rem;margin:1.5rem 0}
.result-card{background:var(--bg-card);border:1px solid var(--border-subtle);border-radius:4px;padding:1.25rem;transition:all var(--transition-fast)}
.result-card:hover{border-color:var(--border-gold);background:var(--bg-card-hover)}
.result-label{font-family:var(--mono);font-size:.68rem;letter-spacing:.08em;text-transform:uppercase;color:var(--text-muted);margin-bottom:.5rem}
.result-value{font-family:var(--serif);font-size:1.3rem;color:var(--gold);font-weight:600}
.result-unit{font-size:.8rem;color:var(--text-secondary);margin-left:.25rem;font-weight:400}
.result-note{font-size:.78rem;color:var(--text-muted);margin-top:.35rem}

/* PDF Viewer */
.pdf-section{margin:2rem 0}
.pdf-viewer{width:100%;height:85vh;border:1px solid var(--border-subtle);border-radius:4px;background:var(--bg-card)}
.pdf-actions{display:flex;gap:.75rem;margin-top:1rem;flex-wrap:wrap}
.btn{display:inline-flex;align-items:center;gap:.4rem;font-family:var(--mono);font-size:.78rem;letter-spacing:.04em;padding:.55rem 1.1rem;border-radius:3px;cursor:pointer;transition:all var(--transition-fast);text-decoration:none;border:1px solid}
.btn-gold{color:var(--gold);border-color:var(--border-gold);background:var(--gold-glow)}
.btn-gold:hover{background:rgba(218,165,32,.25);color:var(--gold)}
.btn-blue{color:var(--blue);border-color:rgba(74,155,217,.3);background:var(--blue-glow)}
.btn-blue:hover{background:rgba(74,155,217,.2);color:var(--blue)}
.btn-outline{color:var(--text-secondary);border-color:var(--border-subtle);background:transparent}
.btn-outline:hover{border-color:var(--text-muted);color:var(--text-primary)}

/* PDF Gallery Row */
.pdf-gallery{display:flex;gap:1rem;overflow-x:auto;padding:1rem 0;margin:1.5rem 0;-webkit-overflow-scrolling:touch}
.pdf-gallery::-webkit-scrollbar{height:6px}
.pdf-gallery::-webkit-scrollbar-track{background:var(--bg-secondary);border-radius:3px}
.pdf-gallery::-webkit-scrollbar-thumb{background:var(--border-gold);border-radius:3px}
.pdf-thumb{flex:0 0 180px;background:var(--bg-card);border:1px solid var(--border-subtle);border-radius:4px;padding:.75rem;cursor:pointer;transition:all var(--transition-fast);text-decoration:none}
.pdf-thumb:hover{border-color:var(--gold);transform:translateY(-2px);box-shadow:0 4px 12px rgba(0,0,0,.3)}
.pdf-thumb.active{border-color:var(--gold);background:var(--gold-glow)}
.pdf-thumb-icon{width:100%;height:100px;background:var(--bg-secondary);border-radius:3px;display:flex;align-items:center;justify-content:center;margin-bottom:.6rem;font-size:2rem;color:var(--text-muted)}
.pdf-thumb-title{font-size:.78rem;color:var(--text-secondary);line-height:1.4;font-weight:500}
.pdf-thumb-version{font-family:var(--mono);font-size:.65rem;color:var(--text-muted);margin-top:.3rem}

/* ========== PAPERS INDEX ========== */
.papers-hero{text-align:center;padding:3rem 2rem 2rem;margin-bottom:2rem}
.papers-hero h1{font-size:2.2rem;margin-bottom:.75rem}
.papers-hero p{max-width:600px;margin:0 auto;color:var(--text-secondary);font-size:1.05rem}

.section-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(320px,1fr));gap:1.25rem;margin:2rem 0}
.section-card{background:var(--bg-card);border:1px solid var(--border-subtle);border-radius:5px;padding:1.5rem;transition:all var(--transition-fast);text-decoration:none;display:block;position:relative;overflow:hidden}
.section-card::before{content:'';position:absolute;top:0;left:0;right:0;height:3px;background:linear-gradient(90deg,var(--gold),var(--blue));opacity:0;transition:opacity var(--transition-fast)}
.section-card:hover{border-color:var(--border-gold);transform:translateY(-2px);box-shadow:0 6px 20px rgba(0,0,0,.3)}
.section-card:hover::before{opacity:1}
.section-num{font-family:var(--mono);font-size:.65rem;letter-spacing:.12em;text-transform:uppercase;color:var(--gold-dim);margin-bottom:.5rem}
.section-card h3{font-family:var(--serif);font-size:1.15rem;color:var(--text-primary);margin-bottom:.5rem;transition:color var(--transition-fast)}
.section-card:hover h3{color:var(--gold)}
.section-card p{font-size:.88rem;color:var(--text-muted);line-height:1.5;margin:0}
.section-count{font-family:var(--mono);font-size:.72rem;color:var(--text-muted);margin-top:.75rem;padding-top:.5rem;border-top:1px solid var(--border-subtle)}

/* Paper list within sections */
.paper-list{list-style:none;margin:1.5rem 0}
.paper-item{border-bottom:1px solid var(--border-subtle);transition:background var(--transition-fast)}
.paper-item:hover{background:var(--bg-card)}
.paper-item a{display:flex;align-items:baseline;gap:.75rem;padding:.85rem 1rem;text-decoration:none;color:var(--text-secondary);transition:color var(--transition-fast)}
.paper-item a:hover{color:var(--gold)}
.paper-item .paper-id{font-family:var(--mono);font-size:.72rem;color:var(--gold-dim);flex-shrink:0;width:70px}
.paper-item .paper-name{flex:1;font-size:.92rem}
.paper-item .paper-status{font-family:var(--mono);font-size:.65rem;padding:.2rem .5rem;border-radius:2px;flex-shrink:0}
.paper-item .status-ready{color:var(--accent-green);background:rgba(74,222,128,.08);border:1px solid rgba(74,222,128,.15)}
.paper-item .status-draft{color:var(--gold);background:var(--gold-glow);border:1px solid var(--border-gold)}
.paper-item .status-placeholder{color:var(--text-muted);background:rgba(255,255,255,.03);border:1px solid var(--border-subtle)}

/* Tables */
table{width:100%;border-collapse:collapse;margin:1.5rem 0;font-size:.9rem}
th{font-family:var(--mono);font-size:.72rem;letter-spacing:.06em;text-transform:uppercase;color:var(--gold);text-align:left;padding:.65rem .75rem;border-bottom:2px solid var(--border-gold);background:var(--bg-card)}
td{padding:.6rem .75rem;border-bottom:1px solid var(--border-subtle);color:var(--text-secondary)}
tr:hover td{background:var(--bg-card)}

/* Cross References */
.crossref-list{display:flex;flex-wrap:wrap;gap:.5rem;margin:1rem 0}
.crossref-tag{font-family:var(--mono);font-size:.72rem;padding:.3rem .65rem;border:1px solid var(--border-subtle);border-radius:3px;color:var(--text-muted);transition:all var(--transition-fast);text-decoration:none}
.crossref-tag:hover{border-color:var(--gold);color:var(--gold);background:var(--gold-glow)}

/* Placeholder/Coming Soon */
.coming-soon-wrap{text-align:center;padding:4rem 2rem}
.coming-soon-wrap h2{color:var(--text-muted);font-size:1.5rem;margin-bottom:1rem}
.coming-soon-wrap p{color:var(--text-muted);max-width:500px;margin:0 auto}
.pdf-placeholder{display:flex;align-items:center;justify-content:center;height:300px;background:var(--bg-card);border:2px dashed var(--border-subtle);border-radius:6px;margin:1.5rem 0}
.pdf-placeholder p{color:var(--text-muted);font-family:var(--mono);font-size:.85rem;text-align:center}

/* ========== RESPONSIVE ========== */
@media(max-width:900px){
  .sidebar{transform:translateX(-100%)}
  .sidebar.open{transform:translateX(0)}
  .main-content{margin-left:0}
  .hamburger{display:flex}
  .nav-links{display:none}
  .content-wrap{padding:2rem 1.25rem 3rem}
  .page-title{font-size:1.4rem}
  .section-grid{grid-template-columns:1fr}
  .results-grid{grid-template-columns:1fr 1fr}
}
@media(max-width:600px){
  .results-grid{grid-template-columns:1fr}
  .page-meta{flex-direction:column;gap:.3rem}
  .pdf-gallery{gap:.75rem}
  .pdf-thumb{flex:0 0 150px}
}