:root{
  --primary-brown:#5d4037;
  --accent-gold:#c5a059;
  --bg-cream:#f4ece1;
  --text-dark:#3e2723;
  --sidebar:#2d1b17;
  --card:#ffffff;
  --muted:#6b5a55;
}

*{box-sizing:border-box}
body{
  margin:0;
  font-family: system-ui, -apple-system, Segoe UI, Roboto, Arial, sans-serif;
  background:var(--bg-cream);
  color:var(--text-dark);
}

.layout{
  display:flex;
  min-height:100vh;
}

/* SIDEBAR */
.sidebar{
  width:300px;
  background:var(--sidebar);
  color:#fff;
  padding:20px;
  display:flex;
  flex-direction:column;
  gap:18px;
  box-shadow: 4px 0 14px rgba(0,0,0,.25);
}
.brand{
  display:flex;
  gap:12px;
  align-items:center;
  padding-bottom:16px;
  border-bottom:1px solid rgba(197,160,89,.45);
}
.brand img{
  width:56px;height:56px;border-radius:12px;object-fit:cover;
  border:2px solid rgba(197,160,89,.65);
}
.brand h2{
  margin:0;
  font-size:16px;
  line-height:1.2;
}
.brand p{
  margin:3px 0 0;
  font-size:12px;
  color: rgba(197,160,89,.95);
}

.nav{
  display:flex;
  flex-direction:column;
  gap:10px;
}
.nav a{
  text-decoration:none;
  color:var(--accent-gold);
  border:1px solid var(--accent-gold);
  padding:12px 12px;
  border-radius:10px;
  font-weight:700;
  transition:.2s;
}
.nav a:hover{
  background:var(--accent-gold);
  color:#fff;
}
.nav a.active{
  background:var(--accent-gold);
  color:#fff;
}

.footer-note{
  margin-top:auto;
  font-size:12px;
  color: rgba(255,255,255,.75);
}
.footer-note b{color:#fff}

/* MAIN */
.main{
  flex:1;
  padding:34px 34px 50px;
  overflow:auto;
}

.top-hero{
  background: linear-gradient(120deg, rgba(93,64,55,.85), rgba(197,160,89,.35)),
              url("images/hero.jpg");
  background-size:cover;
  background-position:center;
  border-radius:18px;
  padding:26px;
  color:#fff;
  box-shadow: 0 10px 26px rgba(0,0,0,.12);
  margin-bottom:18px;
}
.top-hero h1{margin:0 0 6px;font-size:26px}
.top-hero p{margin:0;color:rgba(255,255,255,.85)}

.card{
  background:var(--card);
  border-radius:16px;
  box-shadow: 0 8px 18px rgba(0,0,0,.10);
  padding:22px;
  border-top:6px solid var(--primary-brown);
}

.grid{
  display:grid;
  grid-template-columns: repeat(2, minmax(240px, 1fr));
  gap:16px;
  margin-top:16px;
}

.era-card{
  display:flex;
  gap:14px;
  align-items:stretch;
  padding:14px;
  border-radius:14px;
  border:1px solid rgba(93,64,55,.18);
  cursor:pointer;
  transition:.15s;
}
.era-card:hover{
  transform: translateY(-2px);
  box-shadow: 0 10px 22px rgba(0,0,0,.10);
}
.era-card img{
  width:120px;
  border-radius:12px;
  object-fit:cover;
  border:2px solid rgba(197,160,89,.55);
}
.era-card h3{margin:0 0 6px}
.era-card p{margin:0;color:var(--muted);font-size:13px;line-height:1.35}

.badges{
  margin-top:10px;
  display:flex;
  flex-wrap:wrap;
  gap:8px;
}
.badge{
  font-size:12px;
  padding:6px 10px;
  border-radius:999px;
  background: rgba(197,160,89,.15);
  border:1px solid rgba(197,160,89,.35);
  color: var(--text-dark);
  font-weight:650;
}

/* ERA PAGE */
.era-header{
  display:flex;
  gap:16px;
  align-items:flex-start;
}
.era-header img{
  width:240px;
  border-radius:16px;
  object-fit:cover;
  border:3px solid rgba(197,160,89,.55);
}
.era-header h2{margin:0 0 8px}
.era-header p{margin:0;color:var(--muted);line-height:1.45}

.section-title{
  margin:18px 0 10px;
  font-size:16px;
}

/* CHAT */
.chat{
  margin-top:10px;
  border:2px solid var(--accent-gold);
  border-radius:14px;
  overflow:hidden;
  background:#fff;
  display:flex;
  flex-direction:column;
  height:320px;
}
.chat-messages{
  flex:1;
  padding:14px;
  overflow:auto;
  font-size:14px;
}
.msg{
  margin-bottom:10px;
  padding:10px 12px;
  border-radius:10px;
  max-width:85%;
  line-height:1.35;
}
.msg.bot{
  background:#f3f3f3;
  border-left:4px solid var(--accent-gold);
}
.msg.user{
  margin-left:auto;
  background:var(--bg-cream);
  border-right:4px solid var(--primary-brown);
  text-align:right;
}
.chat-input{
  display:flex;
  border-top:1px solid #eee;
}
.chat-input input{
  flex:1;
  padding:14px;
  border:none;
  outline:none;
}
.chat-input button{
  padding:0 16px;
  border:none;
  background:var(--primary-brown);
  color:#fff;
  font-weight:800;
  cursor:pointer;
}
.quick-buttons{
  display:flex;
  gap:10px;
  flex-wrap:wrap;
  margin-top:10px;
}
.quick-buttons button{
  border:1px solid rgba(93,64,55,.25);
  background:#fff;
  padding:10px 12px;
  border-radius:12px;
  cursor:pointer;
  font-weight:650;
}
.quick-buttons button:hover{
  border-color: var(--accent-gold);
}

/* QUIZ */
.quiz-q{
  padding:14px;
  border:1px solid rgba(93,64,55,.18);
  border-radius:14px;
  margin-top:12px;
}
.quiz-q h3{margin:0 0 10px;font-size:15px}
.choice{
  display:block;
  padding:10px 12px;
  border-radius:12px;
  border:1px solid rgba(197,160,89,.28);
  margin-top:8px;
  cursor:pointer;
}
.choice:hover{
  border-color: var(--accent-gold);
  background: rgba(197,160,89,.08);
}
.quiz-actions{
  margin-top:14px;
  display:flex;
  gap:10px;
}
.primary-btn{
  background:var(--primary-brown);
  color:#fff;
  border:none;
  padding:12px 14px;
  border-radius:12px;
  font-weight:800;
  cursor:pointer;
}
.secondary-btn{
  background:#fff;
  color:var(--primary-brown);
  border:1px solid rgba(93,64,55,.35);
  padding:12px 14px;
  border-radius:12px;
  font-weight:800;
  cursor:pointer;
}

/* GALLERY */
.gallery{
  display:grid;
  grid-template-columns: repeat(3, minmax(180px, 1fr));
  gap:12px;
  margin-top:14px;
}
.gallery img{
  width:100%;
  height:180px;
  object-fit:cover;
  border-radius:14px;
  border:2px solid rgba(197,160,89,.45);
  cursor:pointer;
  transition:.15s;
}
.gallery img:hover{transform:scale(1.01)}
.modal{
  position:fixed;
  inset:0;
  background: rgba(0,0,0,.7);
  display:none;
  align-items:center;
  justify-content:center;
  padding:20px;
}
.modal.open{display:flex}
.modal img{
  max-width:min(900px, 92vw);
  max-height: 90vh;
  border-radius:16px;
  border:3px solid rgba(197,160,89,.7);
}
.modal .close{
  position:absolute;
  top:18px; right:18px;
  background:#fff;
  border:none;
  padding:10px 12px;
  border-radius:12px;
  cursor:pointer;
  font-weight:900;
}

/* responsive */
@media (max-width: 980px){
  .sidebar{width:260px}
  .grid{grid-template-columns:1fr}
  .gallery{grid-template-columns: repeat(2, minmax(160px,1fr));}
}
@media (max-width: 720px){
  .layout{flex-direction:column}
  .sidebar{width:auto}
  .main{padding:18px}
  .era-header{flex-direction:column}
  .era-header img{width:100%}
  .gallery{grid-template-columns:1fr}
}