/* ============================================
   Boulder PC Builders — Main Stylesheet
   ============================================ */

/* --- Custom Properties --- */
:root {
  --color-bg: #0d1117;
  --color-bg-alt: #161b22;
  --color-bg-card: #1c2333;
  --color-bg-input: #0d1117;
  --color-primary: #3b82f6;
  --color-primary-hover: #2563eb;
  --color-secondary: #10b981;
  --color-secondary-hover: #059669;
  --color-text: #e6edf3;
  --color-text-secondary: #8b949e;
  --color-text-muted: #484f58;
  --color-border: #30363d;
  --color-danger: #ef4444;
  --font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, sans-serif;
  --max-width: 1200px;
  --header-height: 70px;
  --radius: 8px;
  --transition: 0.3s ease;
}

/* --- Reset & Base --- */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; }
body {
  font-family: var(--font-family);
  background-color: var(--color-bg);
  color: var(--color-text);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}
img { max-width: 100%; height: auto; display: block; }
a { color: var(--color-primary); text-decoration: none; transition: color var(--transition); }
a:hover { color: var(--color-primary-hover); }
ul { list-style: none; }

/* --- Layout --- */
.container { max-width: var(--max-width); margin: 0 auto; padding: 0 24px; }

/* --- Header --- */
.site-header {
  position: fixed; top: 0; left: 0; right: 0; z-index: 1000;
  background: rgba(13, 17, 23, 0.95);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--color-border);
  height: var(--header-height);
}
.site-header .container {
  display: flex; align-items: center; justify-content: space-between; height: 100%;
}
.logo { display: flex; align-items: center; gap: 10px; color: var(--color-text); }
.logo:hover { color: var(--color-text); }
.logo img { height: 45px; width: 45px; border-radius: 50%; object-fit: cover; }
.logo span { font-weight: 700; font-size: 1.05rem; letter-spacing: -0.02em; white-space: nowrap; }
.nav-links { display: flex; align-items: center; gap: 20px; }
.nav-links a {
  color: var(--color-text-secondary); font-size: 0.88rem; font-weight: 500;
  transition: color var(--transition); padding: 4px 0;
  border-bottom: 2px solid transparent;
}
.nav-links a:hover { color: var(--color-text); }
.nav-links a.active {
  color: var(--color-text); border-bottom-color: var(--color-primary);
}
.hamburger {
  display: none; flex-direction: column; gap: 5px;
  background: none; border: none; cursor: pointer; padding: 8px;
}
.hamburger span {
  display: block; width: 22px; height: 2px;
  background: var(--color-text); transition: var(--transition);
}
.hamburger.active span:nth-child(1) { transform: rotate(45deg) translate(5px, 5px); }
.hamburger.active span:nth-child(2) { opacity: 0; }
.hamburger.active span:nth-child(3) { transform: rotate(-45deg) translate(5px, -5px); }

/* --- Hero Section --- */
.hero {
  position: relative; min-height: 520px;
  display: flex; align-items: center; justify-content: center;
  text-align: center; padding: calc(var(--header-height) + 48px) 24px 80px;
  background-size: cover; background-position: center; background-repeat: no-repeat;
}
.hero::before {
  content: ''; position: absolute; inset: 0;
  background: linear-gradient(180deg, rgba(13,17,23,0.7) 0%, rgba(13,17,23,0.85) 100%);
}
.hero-content { position: relative; z-index: 1; max-width: 800px; }
.hero-logo {
  width: 120px; height: 120px; margin: 0 auto 24px;
  border-radius: 50%; object-fit: cover;
  box-shadow: 0 8px 32px rgba(0,0,0,0.4);
}
.hero h1 {
  font-size: 2.5rem; font-weight: 800; letter-spacing: -0.03em;
  margin-bottom: 16px; line-height: 1.15;
}
.hero h2 {
  font-size: 1.15rem; color: var(--color-text-secondary);
  margin-bottom: 8px; font-weight: 400; line-height: 1.5;
}
.hero .subtitle {
  font-size: 0.9rem; color: var(--color-text-muted); font-style: italic;
}

/* --- Buttons --- */
.btn {
  display: inline-block; padding: 12px 28px; border-radius: var(--radius);
  font-weight: 600; font-size: 0.95rem; cursor: pointer;
  transition: all var(--transition); border: none; text-align: center;
  font-family: inherit;
}
.btn-primary { background: var(--color-primary); color: #fff; }
.btn-primary:hover { background: var(--color-primary-hover); color: #fff; transform: translateY(-1px); box-shadow: 0 4px 12px rgba(59,130,246,0.3); }
.btn-secondary { background: var(--color-secondary); color: #fff; }
.btn-secondary:hover { background: var(--color-secondary-hover); color: #fff; transform: translateY(-1px); box-shadow: 0 4px 12px rgba(16,185,129,0.3); }
.btn-outline { background: transparent; border: 2px solid var(--color-primary); color: var(--color-primary); }
.btn-outline:hover { background: var(--color-primary); color: #fff; }
.btn-group { display: flex; gap: 16px; justify-content: center; margin-top: 24px; flex-wrap: wrap; }
.btn-lg { padding: 16px 36px; font-size: 1.05rem; }

/* --- Sections --- */
.section { padding: 80px 0; }
.section-alt { background: var(--color-bg-alt); }
.section-title {
  font-size: 1.75rem; font-weight: 700; margin-bottom: 12px; letter-spacing: -0.02em;
}
.section-subtitle {
  color: var(--color-text-secondary); font-size: 1.05rem; margin-bottom: 40px; max-width: 600px;
}
.text-center { text-align: center; }
.mx-auto { margin-left: auto; margin-right: auto; }

/* --- Content Rows (Home Page) --- */
.content-row {
  display: grid; grid-template-columns: 1fr 1fr; gap: 48px;
  align-items: center; padding: 40px 0;
}
.content-row.reverse .content-text { order: 2; }
.content-row.reverse .content-image { order: 1; }
.content-row h3 { font-size: 1.4rem; margin-bottom: 16px; line-height: 1.3; }
.content-row p { color: var(--color-text-secondary); line-height: 1.7; font-size: 1rem; }
.content-row img { border-radius: var(--radius); width: 100%; aspect-ratio: 4/3; object-fit: cover; }

/* --- Value Proposition Cards --- */
.value-cards {
  display: grid; grid-template-columns: repeat(auto-fit, minmax(250px, 1fr)); gap: 24px;
}
.value-card {
  background: var(--color-bg-card); border: 1px solid var(--color-border);
  border-radius: var(--radius); padding: 32px;
  transition: transform var(--transition), border-color var(--transition);
}
.value-card:hover { transform: translateY(-4px); border-color: var(--color-primary); }
.value-card .icon {
  font-size: 1.8rem; margin-bottom: 16px;
}
.value-card h4 { font-size: 1.05rem; margin-bottom: 12px; color: var(--color-primary); }
.value-card p { color: var(--color-text-secondary); font-size: 0.93rem; line-height: 1.6; }

/* --- Product Grid --- */
.product-grid {
  display: grid; grid-template-columns: repeat(auto-fill, minmax(340px, 1fr)); gap: 24px;
}
.product-card {
  background: var(--color-bg-card); border: 1px solid var(--color-border);
  border-radius: var(--radius); overflow: hidden;
  transition: transform var(--transition), border-color var(--transition);
}
.product-card:hover { transform: translateY(-4px); border-color: var(--color-primary); }
.product-card a { color: inherit; display: block; }
.product-card-image {
  aspect-ratio: 4/3; overflow: hidden; background: var(--color-bg);
}
.product-card-image img {
  width: 100%; height: 100%; object-fit: cover;
  transition: transform var(--transition);
}
.product-card:hover .product-card-image img { transform: scale(1.05); }
.product-card-body { padding: 20px; }
.product-card-body h3 { font-size: 1.1rem; margin-bottom: 8px; }
.product-card-body .price {
  font-size: 1.2rem; font-weight: 700; color: var(--color-secondary);
}
.product-card-body .price-from {
  font-size: 0.82rem; color: var(--color-text-secondary); font-weight: 400;
}

/* --- Sort Bar --- */
.sort-bar {
  display: flex; align-items: center; gap: 12px; margin-bottom: 32px;
}
.sort-bar label { color: var(--color-text-secondary); font-size: 0.9rem; font-weight: 500; }
.sort-bar select {
  background: var(--color-bg-card); color: var(--color-text);
  border: 1px solid var(--color-border); padding: 8px 32px 8px 12px;
  border-radius: var(--radius); font-size: 0.9rem; font-family: inherit;
  cursor: pointer; appearance: none;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='12' viewBox='0 0 12 12'%3E%3Cpath fill='%238b949e' d='M6 8L1 3h10z'/%3E%3C/svg%3E");
  background-repeat: no-repeat; background-position: right 10px center;
}

/* --- Product Detail Page --- */
.product-detail {
  display: grid; grid-template-columns: 1fr 1fr; gap: 48px;
  padding: calc(var(--header-height) + 40px) 0 60px;
}
.product-image { border-radius: var(--radius); overflow: hidden; }
.product-image img { width: 100%; }
.product-info h1 { font-size: 1.9rem; margin-bottom: 8px; letter-spacing: -0.02em; }
.product-info .tagline {
  color: var(--color-text-secondary); font-size: 1.05rem; margin-bottom: 24px; line-height: 1.5;
}
.product-price {
  font-size: 2rem; font-weight: 700; color: var(--color-secondary); margin-bottom: 24px;
}

/* --- Variant Selectors --- */
.variant-group { margin-bottom: 20px; }
.variant-group label {
  display: block; font-weight: 600; margin-bottom: 8px; font-size: 0.93rem;
}
.variant-group select {
  width: 100%; background: var(--color-bg-input); color: var(--color-text);
  border: 1px solid var(--color-border); padding: 12px 16px;
  border-radius: var(--radius); font-size: 0.95rem; font-family: inherit;
  appearance: none; cursor: pointer;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='12' viewBox='0 0 12 12'%3E%3Cpath fill='%238b949e' d='M6 8L1 3h10z'/%3E%3C/svg%3E");
  background-repeat: no-repeat; background-position: right 12px center;
}
.variant-group select:focus {
  outline: none; border-color: var(--color-primary);
  box-shadow: 0 0 0 3px rgba(59,130,246,0.15);
}
.purchase-btn { width: 100%; margin-top: 16px; padding: 16px; font-size: 1.1rem; }

/* --- Specs Table --- */
.specs-section { margin-top: 32px; }
.specs-section h3 { font-size: 1.15rem; margin-bottom: 16px; }
.specs-table { width: 100%; border-collapse: collapse; }
.specs-table td {
  padding: 10px 0; border-bottom: 1px solid var(--color-border);
}
.specs-table td:first-child { font-weight: 600; color: var(--color-text); width: 35%; }
.specs-table td:last-child { color: var(--color-text-secondary); }
.specs-note {
  margin-top: 16px; color: var(--color-text-muted);
  font-style: italic; font-size: 0.9rem;
}

/* --- Steps --- */
.steps-grid {
  display: grid; grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 24px; margin: 40px 0;
}
.step {
  background: var(--color-bg-card); border: 1px solid var(--color-border);
  border-radius: var(--radius); padding: 28px;
}
.step-number {
  display: inline-flex; align-items: center; justify-content: center;
  width: 40px; height: 40px; border-radius: 50%;
  background: var(--color-primary); color: #fff; font-weight: 700;
  font-size: 1.1rem; margin-bottom: 16px;
}
.step h4 { font-size: 1rem; margin-bottom: 12px; }
.step p { color: var(--color-text-secondary); font-size: 0.93rem; line-height: 1.6; }

/* --- Forms --- */
.form-section { max-width: 700px; margin: 0 auto; }
.form-group { margin-bottom: 20px; }
.form-group label {
  display: block; font-weight: 600; margin-bottom: 8px; font-size: 0.93rem;
}
.form-group label .required { color: var(--color-danger); margin-left: 2px; }
.form-group input,
.form-group select,
.form-group textarea {
  width: 100%; background: var(--color-bg-input); color: var(--color-text);
  border: 1px solid var(--color-border); padding: 12px 16px;
  border-radius: var(--radius); font-size: 0.95rem; font-family: inherit;
  transition: border-color var(--transition);
}
.form-group input:focus,
.form-group select:focus,
.form-group textarea:focus {
  outline: none; border-color: var(--color-primary);
  box-shadow: 0 0 0 3px rgba(59,130,246,0.15);
}
.form-group textarea { min-height: 100px; resize: vertical; }
.form-group input.invalid,
.form-group select.invalid {
  border-color: var(--color-danger);
  box-shadow: 0 0 0 3px rgba(239,68,68,0.15);
}
.form-group .field-error {
  color: var(--color-danger); font-size: 0.82rem; margin-top: 4px; display: none;
}
.form-group input.invalid + .field-error,
.form-group select.invalid + .field-error { display: block; }
.form-submit { text-align: center; margin-top: 32px; }
.form-message {
  text-align: center; padding: 16px; border-radius: var(--radius);
  margin-top: 16px; display: none;
}
.form-message.success {
  display: block; background: rgba(16,185,129,0.1);
  border: 1px solid var(--color-secondary); color: var(--color-secondary);
}
.form-message.error {
  display: block; background: rgba(239,68,68,0.1);
  border: 1px solid var(--color-danger); color: var(--color-danger);
}

/* --- Gallery --- */
.gallery-grid {
  display: grid; grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
  gap: 16px;
}
.gallery-item {
  border-radius: var(--radius); overflow: hidden; cursor: pointer;
}
.gallery-item img {
  width: 100%; aspect-ratio: 4/3; object-fit: cover;
  transition: transform var(--transition);
}
.gallery-item:hover img { transform: scale(1.05); }

/* --- Lightbox --- */
.lightbox {
  display: none; position: fixed; inset: 0; z-index: 2000;
  background: rgba(0,0,0,0.92); align-items: center; justify-content: center;
  padding: 40px;
}
.lightbox.active { display: flex; }
.lightbox img {
  max-width: 90vw; max-height: 85vh; border-radius: var(--radius);
  object-fit: contain;
}
.lightbox-close {
  position: absolute; top: 20px; right: 24px; background: none; border: none;
  color: #fff; font-size: 2rem; cursor: pointer; line-height: 1;
  width: 44px; height: 44px; display: flex; align-items: center; justify-content: center;
}
.lightbox-close:hover { color: var(--color-text-secondary); }

/* --- Device Pairings --- */
.pairing-grid {
  display: grid; grid-template-columns: repeat(auto-fill, minmax(300px, 1fr)); gap: 24px;
}
.pairing-card {
  background: var(--color-bg-card); border: 1px solid var(--color-border);
  border-radius: var(--radius); padding: 24px;
  transition: transform var(--transition), border-color var(--transition);
}
.pairing-card:hover { transform: translateY(-4px); border-color: var(--color-primary); }
.pairing-card .category {
  color: var(--color-primary); font-size: 0.82rem; font-weight: 600;
  text-transform: uppercase; letter-spacing: 0.05em; margin-bottom: 8px;
}
.pairing-card h3 { margin-bottom: 8px; font-size: 1.05rem; }
.pairing-card p { color: var(--color-text-secondary); font-size: 0.9rem; margin-bottom: 16px; line-height: 1.5; }
.pairing-card .external-link {
  display: inline-flex; align-items: center; gap: 6px; font-size: 0.9rem; font-weight: 500;
}
.pairing-card .external-link svg { width: 14px; height: 14px; }

/* --- Configurator --- */
.configurator { max-width: 900px; margin: 0 auto; }
.config-category {
  background: var(--color-bg-card); border: 1px solid var(--color-border);
  border-radius: var(--radius); margin-bottom: 12px; overflow: hidden;
}
.config-category-header {
  display: flex; align-items: center; justify-content: space-between;
  padding: 18px 24px; cursor: pointer;
  transition: background var(--transition);
}
.config-category-header:hover { background: rgba(59,130,246,0.04); }
.config-category-header h3 {
  font-size: 0.95rem; display: flex; align-items: center; gap: 10px;
}
.config-category-header .chevron {
  transition: transform var(--transition); color: var(--color-text-muted);
}
.config-category.open .config-category-header .chevron { transform: rotate(180deg); }
.config-category-header .selected-summary {
  color: var(--color-text-secondary); font-size: 0.85rem; font-weight: 400;
}
.config-options { padding: 0 24px 20px; display: none; }
.config-category.open .config-options { display: block; }
.config-option {
  display: flex; align-items: center; justify-content: space-between;
  padding: 12px 16px; border: 1px solid var(--color-border);
  border-radius: var(--radius); margin-bottom: 8px; cursor: pointer;
  transition: all var(--transition);
}
.config-option:hover { border-color: var(--color-primary); background: rgba(59,130,246,0.04); }
.config-option.selected { border-color: var(--color-primary); background: rgba(59,130,246,0.08); }
.config-option .option-name { font-weight: 500; font-size: 0.93rem; }
.config-option .option-price { color: var(--color-secondary); font-weight: 600; font-size: 0.93rem; }
.config-summary {
  position: sticky; bottom: 0; background: var(--color-bg-alt);
  border: 1px solid var(--color-border); border-radius: var(--radius);
  padding: 24px; display: flex; align-items: center; justify-content: space-between;
  margin-top: 24px; flex-wrap: wrap; gap: 16px;
}
.config-total { font-size: 1.4rem; font-weight: 700; }
.config-total span { color: var(--color-secondary); }

/* --- CTA Section --- */
.cta-section { text-align: center; padding: 60px 24px; }
.cta-section h2 { font-size: 1.6rem; margin-bottom: 8px; letter-spacing: -0.02em; }
.cta-section .customer-service {
  margin-top: 24px; color: var(--color-text-secondary); font-size: 0.93rem;
}
.cta-section .customer-service a { color: var(--color-primary); }

/* --- Info Page (Shipping & Support) --- */
.info-page { padding: calc(var(--header-height) + 48px) 0 60px; }
.info-page .info-content { max-width: 800px; margin: 0 auto; }
.info-page h2 { font-size: 1.6rem; margin-bottom: 20px; letter-spacing: -0.02em; }
.info-page h3 { font-size: 1.25rem; margin: 32px 0 16px; color: var(--color-primary); }
.info-page h3:first-of-type { margin-top: 0; }
.info-page p {
  color: var(--color-text-secondary); line-height: 1.7; margin-bottom: 16px; font-size: 1rem;
}
.info-page a { color: var(--color-primary); }
.info-page a:hover { text-decoration: underline; }

/* --- Footer --- */
.site-footer {
  background: var(--color-bg-alt); border-top: 1px solid var(--color-border);
  padding: 48px 0 24px;
}
.footer-content {
  display: grid; grid-template-columns: 1.2fr 1fr 1fr; gap: 40px; margin-bottom: 32px;
}
.footer-brand h3 { font-size: 1.05rem; margin-bottom: 12px; }
.footer-brand p { color: var(--color-text-secondary); font-size: 0.88rem; line-height: 1.6; }
.footer-nav h4, .footer-contact h4 {
  font-size: 0.85rem; margin-bottom: 16px; color: var(--color-text-muted);
  text-transform: uppercase; letter-spacing: 0.06em; font-weight: 600;
}
.footer-nav ul { list-style: none; }
.footer-nav li { margin-bottom: 8px; }
.footer-nav a { color: var(--color-text-secondary); font-size: 0.88rem; }
.footer-nav a:hover { color: var(--color-text); }
.footer-contact p { color: var(--color-text-secondary); font-size: 0.88rem; }
.footer-contact a { color: var(--color-primary); }
.footer-bottom {
  text-align: center; color: var(--color-text-muted); font-size: 0.82rem;
  padding-top: 24px; border-top: 1px solid var(--color-border);
}

/* --- Responsive --- */
@media (max-width: 768px) {
  .nav-links {
    display: none; position: fixed; top: var(--header-height); left: 0; right: 0;
    background: rgba(13, 17, 23, 0.98); backdrop-filter: blur(12px);
    flex-direction: column; padding: 24px; gap: 16px;
    border-bottom: 1px solid var(--color-border);
  }
  .nav-links.active { display: flex; }
  .hamburger { display: flex; }
  .hero { min-height: 400px; padding-top: calc(var(--header-height) + 24px); padding-bottom: 60px; }
  .hero h1 { font-size: 1.75rem; }
  .hero h2 { font-size: 1rem; }
  .content-row { grid-template-columns: 1fr; gap: 24px; }
  .content-row.reverse .content-text { order: 1; }
  .content-row.reverse .content-image { order: 2; }
  .product-detail { grid-template-columns: 1fr; gap: 24px; padding-top: calc(var(--header-height) + 24px); }
  .footer-content { grid-template-columns: 1fr; gap: 24px; }
  .product-grid { grid-template-columns: 1fr; }
  .steps-grid { grid-template-columns: 1fr 1fr; }
  .gallery-grid { grid-template-columns: repeat(auto-fill, minmax(200px, 1fr)); }
  .config-summary { flex-direction: column; text-align: center; }
}

@media (max-width: 480px) {
  .hero h1 { font-size: 1.4rem; }
  .btn-group { flex-direction: column; align-items: stretch; }
  .btn-group .btn { width: 100%; }
  .section { padding: 60px 0; }
  .steps-grid { grid-template-columns: 1fr; }
  .value-cards { grid-template-columns: 1fr; }
  .logo span { display: none; }
}