:root{
  --bg: #f6f7fb;
  --card: #ffffff;
  --muted: #6b7280;
  --accent: #0f62fe; /* professional blue accent */
  --accent-2: #0b5ed7;
  --border: #e6e9ef;
  --text: #0f1724;
  --radius: 6px; /* subtle squared corners */
  --shadow: 0 1px 0 rgba(15,23,36,0.04);
  --gap: 16px;
  --container-width: 1200px;
}

/* Reset / base */
*{box-sizing:border-box}
html,body{height:100%}
body{
  font-family: Inter, system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial;
  background:var(--bg);
  color:var(--text);
  margin:0;
  -webkit-font-smoothing:antialiased;
  -moz-osx-font-smoothing:grayscale;
  font-size:15px;
  line-height:1.45;
}
a{color:inherit}
img{max-width:100%;height:auto;display:block}

/* Page container */
.wrap{max-width:var(--container-width);margin:0 auto;padding:0 20px}

/* Header */
.site-header{
  background:transparent;
  border-bottom:1px solid var(--border);
  position:sticky;
  top:0;
  z-index:60;
  backdrop-filter:saturate(1.1) blur(4px);
}
.site-header .wrap{
  display:flex;
  align-items:center;
  gap:12px;
  height:72px;
  padding:10px 20px;
}
.brand{
  display:flex;
  align-items:center;
  gap:10px;
  text-decoration:none;
  color:var(--text);
  font-weight:700;
  font-size:18px;
}
.brand .logo{
  width:44px;height:44px;border-radius:6px;background:linear-gradient(180deg,var(--accent),var(--accent-2));display:inline-flex;align-items:center;justify-content:center;color:#fff;font-weight:700;font-size:18px;
}

/* Header center search */
.header-search{
  margin-left:16px;
  flex:1;
  display:flex;
  align-items:center;
}
.search-input{
  width:100%;
  max-width:640px;
  background:var(--card);
  border:1px solid var(--border);
  padding:10px 12px;
  border-radius:6px;
  display:flex;
  gap:8px;
  align-items:center;
}
.search-input input{
  border:0;background:transparent;outline:none;font-size:14px;color:var(--text);width:100%;
}

/* Header nav */
.header-nav{
  display:flex;
  align-items:center;
  gap:10px;
}
.header-nav a{
  color:var(--muted);text-decoration:none;padding:8px 10px;border-radius:6px;font-size:14px;
}
.header-nav a:hover{background:#f0f3fb;color:var(--accent)}

/* Layout: sidebar (left) + main (right) */
.container{
  max-width:var(--container-width);
  margin:22px auto;
  padding:0 20px;
}
.layout{
  display:grid;
  grid-template-columns: 260px 1fr;
  gap:var(--gap);
  align-items:start;
}

/* Sidebar */
.sidebar{
}
.sidebar .card{
  background:var(--card);
  border:1px solid var(--border);
  border-radius:var(--radius);
  padding:14px;
  box-shadow:var(--shadow);
  position:sticky;top:22px;
}
.sidebar h3{margin:0 0 8px 0;font-size:14px;color:var(--muted)}
.category-list{list-style:none;padding:0;margin:0;display:flex;flex-direction:column;gap:6px}
.category-list a{
  display:block;padding:8px 10px;border-radius:6px;color:var(--muted);text-decoration:none;border:1px solid transparent;
}
.category-list a:hover{background:#f4f7ff;color:var(--accent);border-color:#eef3ff}
.category-list a.active{background:var(--accent);color:#fff;border-color:var(--accent)}

/* Main content */
.main{
  min-height:400px;
}

/* Product grid */
.grid{
  display:grid;
  grid-template-columns: repeat(auto-fill,minmax(220px,1fr));
  gap:18px;
}
.card{
  background:var(--card);
  border:1px solid var(--border);
  border-radius:var(--radius);
  overflow:hidden;
  display:flex;
  flex-direction:column;
  height:100%;
  box-shadow:var(--shadow);
}
.card-image{
  background:#f8fafc;
  width:100%;
  height:180px;
  display:flex;
  align-items:center;
  justify-content:center;
  border-bottom:1px solid var(--border);
}
.card-image img{width:100%;height:100%;object-fit:cover}
.card-body{
  padding:12px;
  display:flex;
  flex-direction:column;
  gap:10px;
  flex:1;
}
.card-title{font-size:15px;font-weight:600;color:var(--text);margin:0}
.card-meta{display:flex;justify-content:space-between;align-items:center;gap:8px}
.card-price{font-weight:700;color:var(--accent);font-size:15px}
.card-actions{display:flex;gap:8px;align-items:center}

/* Buttons */
.btn{
  display:inline-flex;align-items:center;justify-content:center;
  gap:8px;
  background:var(--accent);color:#fff;padding:8px 12px;border-radius:6px;border:none;cursor:pointer;font-weight:600;font-size:14px;
}
.btn.secondary{
  background:transparent;color:var(--accent);border:1px solid var(--accent);
}
.btn.ghost{
  background:transparent;color:var(--muted);border:1px solid var(--border);
}

/* Forms / table */
.table{width:100%;border-collapse:collapse}
.table th,.table td{padding:10px;border:1px solid var(--border);text-align:left}
.input{display:block;width:100%;padding:10px;border:1px solid var(--border);border-radius:6px;background:var(--card)}

/* Product detail */
.product-detail{
  display:flex;gap:18px;flex-wrap:wrap;
}
.product-image img{width:420px;height:420px;object-fit:cover;border-radius:6px;border:1px solid var(--border)}
.product-meta{flex:1;min-width:260px}

/* Utility */
.small{font-size:13px;color:var(--muted)}
.muted{color:var(--muted)}
.center{text-align:center}

/* Responsive */
@media (max-width: 980px){
  .layout{grid-template-columns:1fr;gap:12px}
  .sidebar .card{position:static}
  .card-image{height:160px}
  .product-image img{width:100%;height:auto}
  .search-input{max-width:100%}
}

/* Accessibility focus */
a:focus,button:focus,input:focus,select:focus,textarea:focus{
  outline:3px solid rgba(15,98,254,0.12);outline-offset:2px;border-radius:6px;
}