/* Reset & Base */
*, *::before, *::after { margin: 0; padding: 0; box-sizing: border-box; }

:root {
  --bg: #0a0a0a;
  --surface: #111113;
  --surface2: #18181b;
  --border: #27272a;
  --text: #fafafa;
  --text2: #a1a1aa;
  --accent: #c4956a;
  --accent2: #d4a574;
  --tier1: #22c55e;
  --tier2: #3b82f6;
  --tier3: #a855f7;
  --tier4: #f59e0b;
  --tier5: #71717a;
  --radius: 8px;
  --radius-lg: 12px;
}

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

a { color: var(--text2); text-decoration: none; transition: color 0.15s; }
a:hover { color: var(--text); }

/* Nav */
.nav {
  position: fixed; top: 0; left: 0; right: 0; z-index: 100;
  background: rgba(10,10,10,0.8); backdrop-filter: blur(20px);
  border-bottom: 1px solid var(--border);
}
.nav-inner {
  max-width: 1100px; margin: 0 auto; padding: 0 24px;
  height: 60px; display: flex; align-items: center; justify-content: space-between;
}
.logo { font-size: 18px; font-weight: 600; color: var(--text); letter-spacing: -0.5px; }
.logo span { color: var(--accent); }
.nav-toggle {
  display: none; background: none; border: 1px solid var(--border); color: var(--text);
  font-size: 20px; padding: 4px 10px; border-radius: 6px; cursor: pointer; align-items: center; justify-content: center;
}
.nav-links { display: flex; gap: 24px; align-items: center; font-size: 14px; }

/* Buttons */
.btn-primary {
  background: var(--accent); color: #0a0a0a; border: none; padding: 10px 22px;
  border-radius: var(--radius); font-size: 14px; font-weight: 600; cursor: pointer;
  transition: background 0.15s;
}
.btn-primary:hover { background: var(--accent2); }
.btn-outline {
  background: transparent; color: var(--text); border: 1px solid var(--border);
  padding: 10px 22px; border-radius: var(--radius); font-size: 14px; font-weight: 500;
  cursor: pointer; transition: border-color 0.15s;
}
.btn-outline:hover { border-color: var(--text2); }
.full-width { width: 100%; }

/* Active nav link styling */
.nav-links a.active-nav {
  color: var(--text) !important;
  font-weight: 600;
}

/* Pages */
.page { display: none; padding-top: 60px; min-height: 100vh; }
.page.active { display: block; }

/* Hero */
.hero {
  max-width: 700px; margin: 0 auto; padding: 120px 24px 80px; text-align: center;
}
.hero-badge {
  display: inline-block; font-size: 12px; font-weight: 600; text-transform: uppercase;
  letter-spacing: 1.5px; color: var(--accent); margin-bottom: 24px;
  border: 1px solid rgba(196,149,106,0.3); padding: 6px 16px; border-radius: 20px;
}
.hero h1 { font-size: 52px; font-weight: 700; letter-spacing: -1.5px; line-height: 1.1; margin-bottom: 20px; }
.hero em { font-style: italic; color: var(--accent); }
.hero-sub { font-size: 18px; color: var(--text2); max-width: 520px; margin: 0 auto 36px; line-height: 1.7; }
.hero-actions { display: flex; gap: 12px; justify-content: center; }

/* Section */
.section { max-width: 1100px; margin: 0 auto; padding: 80px 24px; }
.section h2 { font-size: 32px; font-weight: 700; letter-spacing: -0.5px; margin-bottom: 12px; text-align: center; }
.section-sub { text-align: center; color: var(--text2); margin-bottom: 48px; font-size: 16px; }

/* Grid */
.grid-3 { display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; margin-top: 48px; }
.card {
  background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius-lg);
  padding: 32px; transition: border-color 0.15s;
}
.card:hover { border-color: var(--text2); }
.card-icon { font-size: 13px; font-weight: 700; color: var(--accent); margin-bottom: 16px; letter-spacing: 1px; }
.card h3 { font-size: 17px; font-weight: 600; margin-bottom: 8px; }
.card p { font-size: 14px; color: var(--text2); line-height: 1.6; }

/* Tiers */
.tiers { display: flex; flex-direction: column; gap: 12px; max-width: 700px; margin: 48px auto 0; }
.tier {
  display: flex; align-items: center; gap: 16px; padding: 20px 24px;
  background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius-lg);
}
.tier-badge {
  font-size: 11px; font-weight: 700; text-transform: uppercase; letter-spacing: 1px;
  padding: 4px 10px; border-radius: 4px; white-space: nowrap;
}
.tier-1 .tier-badge { background: rgba(34,197,94,0.15); color: var(--tier1); }
.tier-2 .tier-badge { background: rgba(59,130,246,0.15); color: var(--tier2); }
.tier-3 .tier-badge { background: rgba(168,85,247,0.15); color: var(--tier3); }
.tier-4 .tier-badge { background: rgba(245,158,11,0.15); color: var(--tier4); }
.tier-5 .tier-badge { background: rgba(113,113,122,0.15); color: var(--tier5); }
.tier-label { font-weight: 600; font-size: 15px; min-width: 160px; }
.tier p { font-size: 14px; color: var(--text2); }

/* CTA */
.cta-section { text-align: center; border-top: 1px solid var(--border); margin-top: 40px; }
.cta-section h2 { margin-bottom: 12px; }
.cta-section p { color: var(--text2); margin-bottom: 32px; font-size: 16px; }

/* Forms */
.form-page { max-width: 600px; margin: 0 auto; padding: 60px 24px 80px; }
.form-page h1 { font-size: 32px; font-weight: 700; letter-spacing: -0.5px; margin-bottom: 8px; }
.form-sub { color: var(--text2); margin-bottom: 40px; font-size: 15px; }
/* Tier hover tooltip (on badges) */
.tier-hover {
  position: relative; display: inline-block; cursor: help;
}
.tier-tooltip {
  display: none; position: absolute; bottom: calc(100% + 8px); right: 0;
  background: var(--surface2); border: 1px solid var(--border); border-radius: var(--radius);
  padding: 6px 10px; font-size: 12px; font-weight: 400; color: var(--text2);
  white-space: nowrap; z-index: 50; pointer-events: none;
  box-shadow: 0 4px 12px rgba(0,0,0,0.3);
}
.tier-hover:hover .tier-tooltip { display: block; }

/* Tier info trigger (? icon with legend popup) */
.tier-info-trigger {
  position: relative; display: inline-flex; align-items: center; justify-content: center;
  width: 18px; height: 18px; border-radius: 50%; background: var(--surface2);
  border: 1px solid var(--border); font-size: 11px; font-weight: 600;
  color: var(--text2); cursor: help; vertical-align: middle; margin-left: 6px;
}
.tier-legend-popup {
  display: none; position: absolute; top: calc(100% + 8px); left: 50%; transform: translateX(-50%);
  background: var(--surface2); border: 1px solid var(--border); border-radius: var(--radius);
  padding: 12px 14px; z-index: 50; white-space: nowrap;
  box-shadow: 0 4px 16px rgba(0,0,0,0.4);
}
.tier-info-trigger:hover .tier-legend-popup { display: block; }

/* Tier legend rows inside popup */
.tier-legend { display: flex; flex-direction: column; gap: 6px; }
.tier-legend-row { display: flex; align-items: center; gap: 10px; font-size: 12px; }
.tier-legend-row .listing-tier { font-size: 9px; min-width: 42px; text-align: center; }
.tier-legend-desc { color: var(--text2); }
.form-group { margin-bottom: 24px; }
.form-group label { display: block; font-size: 13px; font-weight: 600; margin-bottom: 8px; color: var(--text); }
.form-row { display: grid; grid-template-columns: 1fr 1fr; gap: 16px; }

input, select, textarea {
  width: 100%; padding: 12px 14px; background: var(--surface); border: 1px solid var(--border);
  border-radius: var(--radius); color: var(--text); font-size: 14px; font-family: inherit;
  transition: border-color 0.15s; outline: none;
}
input:focus, select:focus, textarea:focus { border-color: var(--accent); }
input::placeholder, textarea::placeholder { color: var(--text2); opacity: 0.5; }
select { cursor: pointer; }
textarea { resize: vertical; }

.field-hint { font-size: 13px; color: var(--text2); margin-bottom: 12px; margin-top: -4px; }
.small-label { font-size: 12px; }
.price-term-grid {
  display: grid; grid-template-columns: repeat(2, 1fr); gap: 12px; margin-top: 8px;
}
.price-term-item {
  display: flex; flex-direction: column; gap: 6px;
}
.price-term-label {
  font-size: 12px; font-weight: 600; color: var(--text2);
}

/* Tier Select (seller) */
.tier-select { display: flex; flex-direction: column; gap: 8px; }
.tier-option { display: flex; align-items: center; gap: 12px; cursor: pointer; }
.tier-option input { width: auto; margin: 0; accent-color: var(--accent); }
.tier-option-inner {
  flex: 1; padding: 12px 16px; background: var(--surface); border: 1px solid var(--border);
  border-radius: var(--radius); font-size: 14px; transition: border-color 0.15s;
}
.tier-option input:checked + .tier-option-inner { border-color: var(--accent); }

/* Tier Filter (buyer) */
.tier-filter { display: flex; gap: 8px; flex-wrap: wrap; }
.tier-pill { cursor: pointer; }
.tier-pill input { display: none; }
.tier-pill span {
  display: inline-block; padding: 8px 16px; background: var(--surface);
  border: 1px solid var(--border); border-radius: 20px; font-size: 13px;
  font-weight: 500; transition: all 0.15s;
}
.tier-pill input:checked + span { border-color: var(--accent); color: var(--accent); background: rgba(196,149,106,0.08); }
.tier-pill:hover span { border-color: var(--text2); }

/* Browse */
.browse-page { max-width: 1100px; margin: 0 auto; padding: 60px 24px 80px; }
.browse-page h1 { font-size: 32px; font-weight: 700; letter-spacing: -0.5px; margin-bottom: 8px; }
.filters { display: flex; gap: 12px; margin: 32px 0 24px; flex-wrap: wrap; align-items: center; }
.filters select { width: auto; min-width: 160px; }
.filters input[type="number"] { width: auto; min-width: 130px; }

/* Brighten text on Browse Clusters and Compute Requests pages */
#page-browse.active .form-sub,
#page-requests.active .form-sub {
  color: #d4d4d8 !important;
}
#page-browse.active .listing-meta-label,
#page-requests.active .listing-meta-label {
  color: #d4d4d8 !important;
}
#page-browse.active p,
#page-requests.active p {
  color: #d4d4d8 !important;
}

.listings-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(320px, 1fr)); gap: 16px; margin-top: 24px; }

.listing-card {
  background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius-lg);
  padding: 24px; transition: border-color 0.15s; position: relative;
}
.listing-card:hover { border-color: var(--text2); }
.listing-card.own-item { border-color: var(--accent); }
.own-badge {
  position: absolute; top: 8px; right: 8px; font-size: 10px; font-weight: 700;
  text-transform: uppercase; letter-spacing: 0.5px; padding: 4px 8px;
  background: rgba(196,149,106,0.15); color: var(--accent); border-radius: 4px;
}
.listing-header { display: flex; justify-content: space-between; align-items: flex-start; margin-bottom: 16px; }
.listing-gpu { font-size: 18px; font-weight: 700; }
.listing-tier {
  font-size: 10px; font-weight: 700; text-transform: uppercase; letter-spacing: 1px;
  padding: 3px 8px; border-radius: 4px;
}
.listing-tier[data-tier="1"] { background: rgba(34,197,94,0.15); color: var(--tier1); }
.listing-tier[data-tier="2"] { background: rgba(59,130,246,0.15); color: var(--tier2); }
.listing-tier[data-tier="3"] { background: rgba(168,85,247,0.15); color: var(--tier3); }
.listing-tier[data-tier="4"] { background: rgba(245,158,11,0.15); color: var(--tier4); }
.listing-tier[data-tier="5"] { background: rgba(113,113,122,0.15); color: var(--tier5); }
.listing-meta { display: flex; flex-direction: column; gap: 8px; }
.listing-meta-row { display: flex; justify-content: space-between; font-size: 13px; }
.listing-meta-label { color: var(--text2); }
.listing-meta-val { font-weight: 600; }

/* Request Card */
.request-card {
  background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius-lg);
  padding: 24px; transition: border-color 0.15s; position: relative;
}
.request-card:hover { border-color: var(--text2); }
.request-card.own-item { border-color: var(--accent); }
.request-header { display: flex; justify-content: space-between; align-items: flex-start; margin-bottom: 16px; }
.request-gpu { font-size: 18px; font-weight: 700; }
.request-min-tier {
  font-size: 11px; font-weight: 600; padding: 4px 10px; border-radius: 4px;
  background: rgba(196,149,106,0.12); color: var(--accent);
}

/* Success */
.success-page { text-align: center; padding: 160px 24px; }
.success-icon {
  width: 64px; height: 64px; border-radius: 50%; background: rgba(34,197,94,0.15);
  color: var(--tier1); font-size: 28px; display: flex; align-items: center;
  justify-content: center; margin: 0 auto 24px;
}
.success-page h1 { font-size: 28px; margin-bottom: 12px; }
.success-page p { color: var(--text2); margin-bottom: 32px; }

/* Footer */
.footer { border-top: 1px solid var(--border); padding: 24px; }
.footer-inner {
  max-width: 1100px; margin: 0 auto; display: flex; justify-content: space-between;
  align-items: center; font-size: 13px; color: var(--text2);
}
.logo-sm { font-weight: 600; color: var(--text2); }
.logo-sm span { color: var(--accent); }
.footer-links { display: flex; gap: 20px; }
.footer-links a { font-size: 13px; }

/* Auth */
.auth-error {
  background: rgba(239,68,68,0.1); border: 1px solid rgba(239,68,68,0.3);
  color: #ef4444; padding: 10px 14px; border-radius: var(--radius);
  font-size: 13px; margin-bottom: 20px;
}

/* Back Link */
.back-link { display: inline-block; color: var(--text2); font-size: 14px; margin-bottom: 24px; }
.back-link:hover { color: var(--text); }

/* Detail Page */
.detail-header { display: flex; align-items: center; gap: 16px; margin-bottom: 32px; }
.detail-header h1 { font-size: 32px; font-weight: 700; letter-spacing: -0.5px; }
.detail-grid { display: flex; flex-direction: column; gap: 12px; margin-bottom: 32px; }
.detail-row {
  display: flex; justify-content: space-between; padding: 12px 16px;
  background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius);
  font-size: 14px;
}
.detail-label { color: var(--text2); }
.detail-val { font-weight: 600; }
.detail-section { margin-bottom: 32px; }
.detail-section h3 { font-size: 15px; font-weight: 600; margin-bottom: 8px; }
.detail-section p { font-size: 14px; color: var(--text2); line-height: 1.7; }
.detail-actions { display: flex; gap: 12px; }

/* Modal */
.modal-overlay {
  position: fixed; top: 0; left: 0; right: 0; bottom: 0; z-index: 200;
  background: rgba(0,0,0,0.6); backdrop-filter: blur(4px);
  display: flex; align-items: center; justify-content: center;
}
.modal {
  background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius-lg);
  padding: 32px; max-width: 480px; width: 90%;
}
.modal h2 { font-size: 20px; font-weight: 700; margin-bottom: 8px; }
.modal-actions { display: flex; gap: 12px; justify-content: flex-end; margin-top: 8px; }

/* Responsive */
@media (max-width: 768px) {
  .hero h1 { font-size: 32px; }
  .grid-3 { grid-template-columns: 1fr; }
  .form-row { grid-template-columns: 1fr; }
  .nav-toggle { display: flex; }
  .nav-links {
    display: none; position: absolute; top: 60px; left: 0; right: 0;
    flex-direction: column; gap: 0; padding: 8px 0;
    background: rgba(10,10,10,0.95); backdrop-filter: blur(20px);
    border-bottom: 1px solid var(--border);
  }
  .nav-links.open { display: flex; }
  .nav-links a { padding: 12px 24px; font-size: 15px; }
  .nav-links a.btn-outline, .nav-links a.btn-primary {
    margin: 4px 24px; text-align: center; border-radius: 8px;
  }
  .nav-links #nav-auth { padding: 8px 24px; }
  .tier { flex-direction: column; align-items: flex-start; gap: 8px; }
  .tier-filter { flex-direction: column; }
}