:root {
  --c-bg: #fafafa;
  --c-surface: #ffffff;
  --c-text: #111827;
  --c-text-muted: #6b7280;
  --c-text-light: #9ca3af;
  --c-border: #e5e7eb;
  --c-border-strong: #d1d5db;
  --c-primary: #1a56db;
  --c-primary-hover: #1e40af;
  --c-accent: #059669;
  --c-warning: #d97706;
  --c-danger: #dc2626;
  --c-badge-green-bg: #dcfce7;
  --c-badge-green-text: #166534;
  --c-badge-yellow-bg: #fef3c7;
  --c-badge-yellow-text: #92400e;
  --c-badge-blue-bg: #dbeafe;
  --c-badge-blue-text: #1e40af;
  --max: 1080px;
  --gap: 1.25rem;
  --radius: 12px;
  --radius-sm: 8px;
  --transition: 0.2s ease;
}

* { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; }

body {
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  line-height: 1.6;
  background: var(--c-bg);
  color: var(--c-text);
  -webkit-font-smoothing: antialiased;
}

img { max-width: 100%; height: auto; display: block; }
a { color: var(--c-primary); text-decoration: none; transition: color var(--transition); }
a:hover { color: var(--c-primary-hover); }

.container { width: min(100% - 2rem, var(--max)); margin-inline: auto; padding: 1.5rem 0; }

/* HEADER */
header {
  background: var(--c-surface);
  border-bottom: 1px solid var(--c-border);
  padding: 0.75rem 0;
  position: sticky;
  top: 0;
  z-index: 100;
}

.nav-wrap {
  display: flex; align-items: center; justify-content: space-between;
  gap: 1rem; flex-wrap: wrap;
}

.brand { display: flex; align-items: center; text-decoration: none; }
.brand img { height: 44px; width: auto; }

.nav-toggle {
  display: none; background: none; border: none;
  font-size: 1.5rem; cursor: pointer; color: var(--c-text); padding: 0.5rem;
}

nav ul { display: flex; gap: 1.5rem; list-style: none; flex-wrap: wrap; }
nav a { font-size: 0.95rem; font-weight: 500; color: var(--c-text-muted); transition: color var(--transition); }
nav a:hover, nav a[aria-current="page"] { color: var(--c-primary); }

/* HERO */
.hero { padding: 3rem 0 2rem; }
.hero h1 { font-size: clamp(2rem, 4vw, 2.75rem); font-weight: 800; line-height: 1.15; letter-spacing: -0.03em; margin-bottom: 0.75rem; }
.lead { font-size: 1.1rem; color: var(--c-text-muted); max-width: 56ch; line-height: 1.7; }

/* FEATURED */
.featured-article {
  background: var(--c-surface); border: 1px solid var(--c-border);
  border-radius: var(--radius); padding: 2rem; margin: 1.5rem 0; position: relative;
}
.featured-article h2 { font-size: 1.5rem; font-weight: 700; margin: 0 0 0.5rem; letter-spacing: -0.02em; }
.featured-article h2 a { color: var(--c-primary); }
.featured-article p { color: var(--c-text-muted); margin: 0; }

/* CATEGORY GRID */
.category-grid {
  display: grid; gap: var(--gap);
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  margin: 2rem 0;
}

.category-card {
  background: var(--c-surface); border: 1px solid var(--c-border);
  border-radius: var(--radius); padding: 2rem; text-decoration: none;
  text-align: center; display: flex; flex-direction: column;
  align-items: center; justify-content: center; min-height: 180px;
  transition: border-color var(--transition), box-shadow var(--transition);
}

.category-card:hover { border-color: var(--c-primary); box-shadow: 0 4px 12px rgba(0,0,0,0.08); }
.category-card .icon { font-size: 2.5rem; margin-bottom: 1rem; }
.category-card h2 { font-size: 1.15rem; font-weight: 700; margin: 0 0 0.5rem; color: var(--c-text); }
.category-card p { margin: 0; font-size: 0.9rem; color: var(--c-text-muted); }

/* PRODUCT GRID */
.products-section { margin: 3rem 0; }
.products-section h2 { font-size: 1.75rem; font-weight: 700; margin-bottom: 2rem; letter-spacing: -0.02em; }

.product-grid {
  display: grid; gap: var(--gap);
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
}

.product-card {
  background: var(--c-surface); border: 1px solid var(--c-border);
  border-radius: var(--radius); overflow: hidden;
  display: flex; flex-direction: column; transition: box-shadow var(--transition);
}

.product-card:hover { box-shadow: 0 8px 24px rgba(0,0,0,0.12); }

.product-image {
  aspect-ratio: 16/10; background: var(--c-bg);
  display: grid; place-items: center; padding: 2rem; position: relative;
}
.product-image img { max-height: 100%; max-width: 100%; object-fit: contain; }

.badge {
  position: absolute; top: 1rem; left: 1rem;
  padding: 0.4rem 0.8rem; border-radius: 20px;
  font-size: 0.75rem; font-weight: 700;
  text-transform: uppercase; letter-spacing: 0.05em;
}
.badge-best { background: var(--c-badge-green-bg); color: var(--c-badge-green-text); }
.badge-top { background: var(--c-badge-yellow-bg); color: var(--c-badge-yellow-text); }
.badge-premium { background: var(--c-badge-blue-bg); color: var(--c-badge-blue-text); }

.product-body { padding: 1.5rem; flex: 1; display: flex; flex-direction: column; }
.product-body h3 { font-size: 1.25rem; font-weight: 700; margin-bottom: 0.5rem; color: var(--c-text); }
.product-meta { font-size: 0.85rem; color: var(--c-text-muted); margin-bottom: 1rem; }
.rating { color: var(--c-warning); font-size: 1.1rem; margin-bottom: 1rem; }
.rating-text { color: var(--c-text-muted); font-size: 0.9rem; margin-left: 0.5rem; }
.price { font-size: 2rem; font-weight: 800; color: var(--c-text); margin-bottom: 1.5rem; }

.features { list-style: none; margin-bottom: 1.5rem; flex: 1; }
.features li { padding: 0.4rem 0; font-size: 0.9rem; color: var(--c-text-muted); position: relative; padding-left: 1.5rem; }
.features li:before { content: "\2713"; position: absolute; left: 0; color: var(--c-accent); font-weight: 700; }

.cta {
  display: block; background: var(--c-primary); color: white;
  text-align: center; padding: 1rem; border-radius: var(--radius-sm);
  font-weight: 600; font-size: 1rem; transition: background var(--transition);
}
.cta:hover { background: var(--c-primary-hover); color: white; }

.center-text { text-align: center; margin-top: 2rem; }
.center-text a { font-weight: 600; font-size: 1.1rem; }

/* ARTICLE STYLES (for guias pages) */
article { max-width: 760px; margin: 0 auto; padding: 2rem 0; }
article h1 { font-size: clamp(1.75rem, 4vw, 2.5rem); font-weight: 800; line-height: 1.2; letter-spacing: -0.03em; margin-bottom: 0.75rem; }
article h2 { font-size: 1.5rem; font-weight: 700; margin: 2.5rem 0 1rem; padding-top: 1.5rem; border-top: 1px solid var(--c-border); letter-spacing: -0.02em; }
article h3 { font-size: 1.15rem; font-weight: 700; margin: 1.5rem 0 0.5rem; }
article p { margin-bottom: 1rem; color: var(--c-text-muted); line-height: 1.7; }
article strong { color: var(--c-text); }

.article-meta { font-size: 0.85rem; color: var(--c-text-light); margin-bottom: 2rem; }

/* Tables in articles */
.table-wrap { overflow-x: auto; margin: 1.5rem 0; }
table { width: 100%; border-collapse: collapse; font-size: 0.9rem; }
th { background: var(--c-bg); padding: 0.75rem; text-align: left; font-weight: 600; font-size: 0.8rem; text-transform: uppercase; letter-spacing: 0.04em; color: var(--c-text-muted); border-bottom: 2px solid var(--c-border); }
td { padding: 0.75rem; border-bottom: 1px solid var(--c-border); color: var(--c-text); }
tr:hover td { background: var(--c-bg); }

/* Article product cards */
article .product-card {
  border: 1px solid var(--c-border); border-radius: var(--radius);
  padding: 1.75rem; margin: 1.5rem 0; background: var(--c-surface);
}
article .product-card h3 { font-size: 1.3rem; margin: 0 0 0.5rem; }

.specs { display: grid; grid-template-columns: repeat(2, 1fr); gap: 0.5rem; background: var(--c-bg); border: 1px solid var(--c-border); border-radius: var(--radius-sm); padding: 1rem; margin: 1rem 0; }
.specs span { font-size: 0.9rem; }
.specs strong { color: var(--c-text); }

.pros-cons { display: grid; grid-template-columns: 1fr 1fr; gap: 1.5rem; margin: 1rem 0; }
.pros h4 { color: var(--c-accent); font-size: 0.85rem; text-transform: uppercase; letter-spacing: 0.04em; margin-bottom: 0.5rem; }
.cons h4 { color: var(--c-danger); font-size: 0.85rem; text-transform: uppercase; letter-spacing: 0.04em; margin-bottom: 0.5rem; }
.pros ul, .cons ul { list-style: none; padding: 0; }
.pros li, .cons li { font-size: 0.9rem; padding: 0.2rem 0; color: var(--c-text-muted); }
.pros li::before { content: "\2713 "; color: var(--c-accent); font-weight: 700; }
.cons li::before { content: "\2717 "; color: var(--c-danger); font-weight: 700; }

.alt { background: var(--c-bg); border: 1px solid var(--c-border); border-radius: var(--radius-sm); padding: 0.85rem; margin: 1rem 0; font-size: 0.85rem; color: var(--c-text-muted); }
.alt strong { color: var(--c-text); }

.transparency { background: #f0f9ff; border: 1px solid #bae6fd; border-radius: var(--radius-sm); padding: 1rem; margin: 1.5rem 0; font-size: 0.9rem; color: var(--c-text-muted); }

.install-cards { display: grid; grid-template-columns: 1fr 1fr; gap: 1rem; margin: 1.5rem 0; }
.install-card { background: var(--c-bg); border: 1px solid var(--c-border); border-radius: var(--radius-sm); padding: 1rem; }
.install-card h4 { font-size: 0.9rem; margin-bottom: 0.4rem; color: var(--c-primary); }
.install-card p { font-size: 0.9rem; margin: 0; }

details { border-bottom: 1px solid var(--c-border); padding: 1rem 0; }
summary { cursor: pointer; font-weight: 600; list-style: none; color: var(--c-text); display: flex; justify-content: space-between; align-items: center; }
summary::-webkit-details-marker { display: none; }
summary::after { content: "+"; color: var(--c-text-light); font-size: 1.25rem; font-weight: 300; }
details[open] summary::after { content: "\2212"; }
details p { margin-top: 0.75rem; margin-bottom: 0; }

/* TOOLS STYLES */
.tool-section {
  background: var(--c-surface); border: 1px solid var(--c-border);
  border-radius: var(--radius); padding: 2rem; margin: 2rem 0;
}
.tool-section h2 { font-size: 1.35rem; font-weight: 700; margin: 0 0 1.5rem; border: none; padding-top: 0; }

.calc-form { display: grid; gap: 1rem; max-width: 440px; }
.calc-form label { display: flex; flex-direction: column; gap: 0.35rem; font-size: 0.9rem; font-weight: 500; }
.calc-form input, .calc-form select {
  padding: 0.6rem 0.75rem; background: var(--c-surface);
  border: 1px solid var(--c-border-strong); border-radius: var(--radius-sm);
  color: var(--c-text); font-size: 0.95rem; transition: border-color var(--transition);
}
.calc-form input:focus, .calc-form select:focus { outline: none; border-color: var(--c-primary); }
.calc-form .btn {
  background: var(--c-primary); color: #fff; border: none;
  padding: 0.75rem 1.5rem; border-radius: var(--radius-sm);
  font-size: 0.95rem; font-weight: 600; cursor: pointer;
  justify-self: start; width: auto; transition: background var(--transition);
}
.calc-form .btn:hover { background: var(--c-primary-hover); }

.calc-result {
  margin-top: 1.25rem; padding: 1.25rem;
  background: var(--c-bg); border: 1px solid var(--c-border);
  border-radius: var(--radius-sm);
}
.calc-result p { margin: 0.3rem 0; font-size: 0.95rem; }
.calc-result .highlight { color: var(--c-accent); font-size: 1.15rem; font-weight: 700; }
.calc-result .error { color: var(--c-danger); }
.calc-result .note { font-size: 0.8rem; color: var(--c-text-light); border-top: 1px solid var(--c-border); padding-top: 0.75rem; margin-top: 0.75rem; font-style: italic; }

.compat-table-wrap { overflow-x: auto; border: 1px solid var(--c-border); border-radius: var(--radius-sm); }
.compat-table { width: 100%; border-collapse: collapse; font-size: 0.9rem; background: var(--c-surface); }
.compat-table th, .compat-table td { padding: 0.75rem; text-align: left; border-bottom: 1px solid var(--c-border); }
.compat-table th { background: var(--c-bg); font-weight: 600; font-size: 0.8rem; text-transform: uppercase; letter-spacing: 0.04em; color: var(--c-text-muted); }
.compat-table tr:hover td { background: var(--c-bg); }

.compat-controls { display: flex; gap: 0.75rem; margin-bottom: 1rem; flex-wrap: wrap; }
.compat-controls input, .compat-controls select {
  padding: 0.6rem 0.75rem; background: var(--c-surface);
  border: 1px solid var(--c-border-strong); border-radius: var(--radius-sm);
  color: var(--c-text); font-size: 0.9rem; flex: 1; min-width: 160px;
}
.compat-controls input:focus, .compat-controls select:focus { outline: none; border-color: var(--c-primary); }

/* FOOTER */
footer { border-top: 1px solid var(--c-border); padding: 2rem 0; margin-top: 4rem; color: var(--c-text-light); font-size: 0.85rem; text-align: center; }

/* RESPONSIVE */
@media (max-width: 768px) {
  .nav-toggle { display: block; }
  nav { display: none; width: 100%; }
  nav.open { display: block; }
  nav ul { flex-direction: column; gap: 0; margin-top: 1rem; }
  nav li { border-bottom: 1px solid var(--c-border); }
  nav a { display: block; padding: 1rem 0; }
  .category-grid { grid-template-columns: 1fr; }
  .product-grid { grid-template-columns: 1fr; }
  .hero { padding: 2rem 0 1rem; }
  .hero h1 { font-size: 1.75rem; }
  .pros-cons { grid-template-columns: 1fr; gap: 0.75rem; }
  .specs { grid-template-columns: 1fr; }
  .install-cards { grid-template-columns: 1fr; }
  .calc-form { grid-template-columns: 1fr; }
}