/* ================================================
   SponsorLens — Competition-Grade Landing Page
   Design system: Dark-mode accent, Z-pattern flow,
   conversion-optimized visual hierarchy.
   ================================================ */

/* ===== RESET ===== */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

:root {
  /* Core palette — deep navy + emerald accent (not "student green") */
  --bg: #fafbfc;
  --bg-dark: #0c1117;
  --bg-dark-card: #161b22;
  --bg-subtle: #f3f5f7;
  --surface: #ffffff;
  --border: #d8dee4;
  --border-light: #e8ecf0;

  /* Accent — professional emerald, not mint */
  --accent: #059669;
  --accent-hover: #047857;
  --accent-glow: rgba(5, 150, 105, 0.15);
  --accent-soft: #d1fae5;

  /* Verdict colors */
  --strong: #059669;
  --strong-bg: #ecfdf5;
  --risky: #d97706;
  --risky-bg: #fffbeb;
  --low: #dc2626;
  --low-bg: #fef2f2;

  /* Text */
  --text: #1a1f25;
  --text-secondary: #4b5563;
  --text-muted: #6b7280;
  --text-light: #e5e7eb;
  --text-light-secondary: #9ca3af;

  /* Spacing & shapes */
  --radius: 12px;
  --radius-lg: 16px;
  --shadow-sm: 0 1px 3px rgba(0,0,0,0.06);
  --shadow: 0 4px 16px rgba(0,0,0,0.06);
  --shadow-lg: 0 12px 40px rgba(0,0,0,0.08);
  --shadow-glow: 0 0 40px var(--accent-glow);

  --max-width: 1120px;
  --transition: 0.2s cubic-bezier(0.4, 0, 0.2, 1);
}

html { scroll-behavior: smooth; scroll-padding-top: 64px; }

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

.container { width: min(var(--max-width), 90%); margin: 0 auto; }

/* ===== NAVIGATION ===== */
.nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  background: rgba(250, 251, 252, 0.85);
  backdrop-filter: blur(12px) saturate(180%);
  -webkit-backdrop-filter: blur(12px) saturate(180%);
  border-bottom: 1px solid var(--border-light);
  transition: background var(--transition);
}

.nav-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 5%;
  height: 56px;
}

.nav-logo {
  font-weight: 800;
  font-size: 1.1rem;
  text-decoration: none;
  color: var(--text);
  letter-spacing: -0.5px;
}
.nav-logo span { color: var(--accent); }

.nav-links {
  display: flex;
  align-items: center;
  gap: 28px;
}

.nav-links a {
  font-size: 0.85rem;
  font-weight: 500;
  color: var(--text-secondary);
  text-decoration: none;
  transition: color var(--transition);
}
.nav-links a:hover { color: var(--text); }

.nav-cta {
  padding: 6px 16px !important;
  background: var(--text) !important;
  color: white !important;
  border-radius: 8px;
  font-weight: 600 !important;
  transition: opacity var(--transition) !important;
}
.nav-cta:hover { opacity: 0.85; color: white !important; }

/* ===== HERO ===== */
.hero {
  position: relative;
  padding: 120px 0 80px;
  overflow: hidden;
  background: var(--bg);
}

.hero-bg {
  position: absolute;
  inset: 0;
  background:
    radial-gradient(ellipse 600px 400px at 20% 50%, var(--accent-glow), transparent),
    radial-gradient(ellipse 500px 350px at 80% 30%, rgba(99, 102, 241, 0.06), transparent);
  pointer-events: none;
}

.hero-grid {
  display: grid;
  grid-template-columns: 1.1fr 0.9fr;
  gap: 64px;
  align-items: center;
}

.badge {
  display: inline-block;
  padding: 6px 14px;
  border-radius: 999px;
  font-size: 0.75rem;
  font-weight: 600;
  letter-spacing: 0.02em;
  color: var(--accent);
  background: var(--accent-soft);
  margin-bottom: 24px;
}

h1 {
  font-size: clamp(2.4rem, 4.5vw, 3.4rem);
  font-weight: 900;
  letter-spacing: -1.5px;
  color: var(--text);
  line-height: 1.08;
}

.gradient-text {
  background: linear-gradient(135deg, var(--accent) 0%, #0d9488 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.lead {
  max-width: 540px;
  font-size: 1.05rem;
  color: var(--text-secondary);
  margin-top: 20px;
  line-height: 1.7;
}

.hero-stats {
  display: flex;
  gap: 32px;
  margin-top: 32px;
  padding-top: 24px;
  border-top: 1px solid var(--border-light);
}

.stat { display: flex; flex-direction: column; }
.stat-num { font-size: 1.5rem; font-weight: 800; color: var(--text); letter-spacing: -0.5px; }
.stat-label { font-size: 0.75rem; color: var(--text-muted); margin-top: 2px; }

.cta-row { display: flex; flex-wrap: wrap; gap: 12px; margin-top: 28px; }
.cta-center { justify-content: center; }

.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 12px 24px;
  border-radius: 10px;
  font-size: 0.88rem;
  font-weight: 600;
  text-decoration: none;
  transition: all var(--transition);
  cursor: pointer;
  border: none;
}

.btn-primary {
  background: var(--text);
  color: white;
  box-shadow: var(--shadow);
}
.btn-primary:hover {
  box-shadow: var(--shadow-lg);
  transform: translateY(-1px);
}

.btn-ghost {
  background: transparent;
  color: var(--text-secondary);
  border: 1px solid var(--border);
}
.btn-ghost:hover {
  background: var(--bg-subtle);
  border-color: var(--text-muted);
  color: var(--text);
}

.btn svg { flex-shrink: 0; }

/* ===== HERO MOCKUP ===== */
.mockup-window {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-lg), var(--shadow-glow);
  overflow: hidden;
  animation: float 6s ease-in-out infinite;
}

@keyframes float {
  0%, 100% { transform: translateY(0); }
  50% { transform: translateY(-8px); }
}

.mockup-dots {
  display: flex;
  gap: 6px;
  padding: 12px 16px;
  background: var(--bg-subtle);
  border-bottom: 1px solid var(--border-light);
}
.mockup-dots span {
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background: var(--border);
}

.mockup-content { padding: 24px; }

.mockup-header {
  font-weight: 800;
  font-size: 1.1rem;
  color: var(--text);
  margin-bottom: 16px;
  letter-spacing: -0.5px;
}

.mockup-verdict {
  display: inline-block;
  padding: 4px 14px;
  border-radius: 999px;
  font-size: 0.8rem;
  font-weight: 700;
}
.mockup-verdict.strong { background: var(--strong-bg); color: #065f46; }

.mockup-score {
  font-size: 2.5rem;
  font-weight: 900;
  color: var(--strong);
  margin: 12px 0;
  letter-spacing: -1px;
}
.mockup-score small { font-size: 1rem; color: var(--text-muted); font-weight: 500; }

.mockup-signals { display: flex; flex-direction: column; gap: 6px; margin-bottom: 16px; }

.signal {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 0.82rem;
  color: var(--text-secondary);
  padding: 6px 10px;
  border-radius: 6px;
  background: var(--bg-subtle);
}
.signal.positive::before {
  content: '';
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--strong);
  flex-shrink: 0;
}

.mockup-action {
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--strong);
  padding-top: 12px;
  border-top: 1px solid var(--border-light);
}

/* ===== SECTIONS ===== */
.section { padding: 96px 0; }

.section-dark {
  background: var(--bg-dark);
  color: var(--text-light);
}

.section-subtle { background: var(--bg-subtle); }

.section-header { max-width: 640px; margin-bottom: 48px; }
.section-header.light h2 { color: var(--text-light); }
.section-header.light .section-sub { color: var(--text-light-secondary); }
.section-header.light .overline { color: var(--accent); }

.overline {
  font-size: 0.75rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: 12px;
}

.section-header h2 {
  font-size: clamp(1.6rem, 3vw, 2.2rem);
  font-weight: 800;
  color: var(--text);
  line-height: 1.2;
  letter-spacing: -0.5px;
}

.section-sub {
  font-size: 1rem;
  color: var(--text-secondary);
  margin-top: 12px;
  line-height: 1.65;
}

/* ===== CARDS (Problem section) ===== */
.grid-3 {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
}

.card {
  background: var(--surface);
  border: 1px solid var(--border-light);
  border-radius: var(--radius);
  padding: 28px 24px;
  transition: transform var(--transition), box-shadow var(--transition);
}
.card:hover {
  transform: translateY(-3px);
  box-shadow: var(--shadow-lg);
}

.card-icon {
  width: 44px;
  height: 44px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: 10px;
  background: var(--accent-soft);
  color: var(--accent);
  margin-bottom: 16px;
}
.card-icon.warning { background: var(--risky-bg); color: var(--risky); }
.card-icon.danger { background: var(--low-bg); color: var(--low); }

.card h3 {
  font-size: 1rem;
  font-weight: 700;
  color: var(--text);
  margin-bottom: 8px;
}
.card p {
  font-size: 0.88rem;
  color: var(--text-secondary);
  line-height: 1.55;
}

/* ===== STEPS ===== */
.steps-row {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 0;
  margin: 48px 0;
}

.step {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 12px;
  padding: 0 24px;
}

.step .step-num {
  width: 40px;
  height: 40px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: 50%;
  background: var(--accent);
  color: white;
  font-size: 0.85rem;
  font-weight: 700;
  flex-shrink: 0;
}

.step p {
  font-size: 0.88rem;
  font-weight: 500;
  color: var(--text-light-secondary);
  text-align: center;
}

.step-line {
  width: 48px;
  height: 2px;
  background: linear-gradient(90deg, var(--accent), rgba(5,150,105,0.2));
  flex-shrink: 0;
}

/* ===== FEATURES GRID ===== */
.features-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 20px;
}

.feature {
  display: flex;
  gap: 16px;
  padding: 24px;
  background: var(--bg-dark-card);
  border: 1px solid rgba(255,255,255,0.06);
  border-radius: var(--radius);
  transition: border-color var(--transition);
}
.feature:hover { border-color: rgba(255,255,255,0.12); }

.feature-icon {
  width: 40px;
  height: 40px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: 10px;
  background: rgba(5, 150, 105, 0.1);
  color: var(--accent);
  flex-shrink: 0;
}

.feature h4 {
  font-size: 0.92rem;
  font-weight: 700;
  color: var(--text-light);
  margin-bottom: 4px;
}
.feature p {
  font-size: 0.82rem;
  color: var(--text-light-secondary);
  line-height: 1.5;
}

/* ===== DEMO CARDS ===== */
.demo-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
  margin-bottom: 32px;
}

.demo-card {
  background: var(--surface);
  border: 1px solid var(--border-light);
  border-radius: var(--radius);
  overflow: hidden;
  transition: transform var(--transition), box-shadow var(--transition);
}
.demo-card:hover {
  transform: translateY(-3px);
  box-shadow: var(--shadow-lg);
}

.demo-top {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 16px 20px;
}
.demo-top.strong-border { border-bottom: 3px solid var(--strong); }
.demo-top.risky-border { border-bottom: 3px solid var(--risky); }
.demo-top.low-border { border-bottom: 3px solid var(--low); }

.verdict-badge {
  padding: 4px 10px;
  border-radius: 6px;
  font-size: 0.75rem;
  font-weight: 700;
  letter-spacing: 0.02em;
}
.strong-badge { background: var(--strong-bg); color: #065f46; }
.risky-badge { background: var(--risky-bg); color: #92400e; }
.low-badge { background: var(--low-bg); color: #991b1b; }

.verdict-score {
  font-size: 0.85rem;
  font-weight: 800;
  color: var(--text);
  letter-spacing: -0.5px;
}

.demo-card h3 {
  font-size: 0.95rem;
  font-weight: 700;
  color: var(--text);
  padding: 16px 20px 12px;
}

.evidence-list {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  padding: 0 20px 12px;
}

.evidence {
  font-size: 0.72rem;
  font-weight: 500;
  padding: 3px 8px;
  border-radius: 4px;
}
.evidence.positive { background: var(--strong-bg); color: #065f46; }
.evidence.neutral { background: #f3f4f6; color: #374151; }
.evidence.warning { background: var(--risky-bg); color: #92400e; }
.evidence.negative { background: var(--low-bg); color: #991b1b; }

.demo-recommendation {
  font-size: 0.82rem;
  font-weight: 600;
  padding: 12px 20px 16px;
  color: var(--strong);
  border-top: 1px solid var(--border-light);
  margin: 0 0;
}
.demo-recommendation.caution { color: var(--risky); }
.demo-recommendation.skip { color: var(--low); }

/* ===== MESSAGE STUDIO ===== */
.message-studio {
  background: var(--surface);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-lg);
  padding: 32px;
  box-shadow: var(--shadow);
}

.studio-header h3 {
  font-size: 1.1rem;
  font-weight: 700;
  color: var(--text);
  margin-bottom: 4px;
}
.studio-header p {
  font-size: 0.88rem;
  color: var(--text-muted);
  margin-bottom: 20px;
}

.studio-message {
  background: var(--bg-subtle);
  border: 1px solid var(--border-light);
  border-left: 3px solid var(--accent);
  border-radius: 8px;
  padding: 20px;
  margin-bottom: 16px;
}
.studio-message p {
  font-size: 0.9rem;
  color: var(--text);
  font-style: italic;
  line-height: 1.65;
}

.studio-variants {
  display: flex;
  gap: 8px;
}

.variant {
  padding: 6px 14px;
  border-radius: 6px;
  font-size: 0.78rem;
  font-weight: 600;
  color: var(--text-muted);
  background: var(--bg-subtle);
  border: 1px solid var(--border-light);
  cursor: pointer;
  transition: all var(--transition);
}
.variant.active {
  background: var(--text);
  color: white;
  border-color: var(--text);
}
.variant:hover:not(.active) {
  border-color: var(--text-muted);
  color: var(--text);
}

/* ===== TRUST GRID ===== */
.trust-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 16px;
}

.trust-item {
  display: flex;
  gap: 16px;
  padding: 20px;
  background: var(--bg-dark-card);
  border: 1px solid rgba(255,255,255,0.06);
  border-radius: var(--radius);
}

.trust-item.full-width {
  grid-column: 1 / -1;
}

.trust-icon {
  width: 40px;
  height: 40px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: 10px;
  background: rgba(5, 150, 105, 0.1);
  color: var(--accent);
  flex-shrink: 0;
}
.trust-icon.shield { background: rgba(5, 150, 105, 0.15); }
.trust-icon.subtle { background: rgba(255,255,255,0.04); color: var(--text-light-secondary); }

.trust-item h4 {
  font-size: 0.88rem;
  font-weight: 700;
  color: var(--text-light);
  margin-bottom: 4px;
}
.trust-item p {
  font-size: 0.82rem;
  color: var(--text-light-secondary);
  line-height: 1.5;
}

/* ===== TECH PILLS ===== */
.tech-pills {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

.tech-pills span {
  padding: 8px 16px;
  background: var(--surface);
  border: 1px solid var(--border-light);
  border-radius: 999px;
  font-size: 0.82rem;
  font-weight: 600;
  color: var(--text);
  transition: border-color var(--transition), box-shadow var(--transition);
}
.tech-pills span:hover {
  border-color: var(--accent);
  box-shadow: var(--shadow-glow);
}

/* ===== INSTALL ===== */
.install-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 16px;
  max-width: 800px;
}

.install-step {
  display: flex;
  gap: 16px;
  padding: 20px;
  background: var(--surface);
  border: 1px solid var(--border-light);
  border-radius: var(--radius);
  transition: box-shadow var(--transition);
}
.install-step:hover { box-shadow: var(--shadow); }

.install-step .step-num {
  width: 36px;
  height: 36px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: 50%;
  background: var(--text);
  color: white;
  font-size: 0.82rem;
  font-weight: 700;
  flex-shrink: 0;
}

.install-step h4 {
  font-size: 0.88rem;
  font-weight: 700;
  color: var(--text);
  margin-bottom: 4px;
}

.install-step code {
  font-family: 'SF Mono', 'Cascadia Code', 'Fira Code', monospace;
  font-size: 0.78rem;
  padding: 2px 8px;
  background: var(--bg-subtle);
  border: 1px solid var(--border-light);
  border-radius: 4px;
  color: var(--accent-hover);
  display: inline-block;
  margin-top: 2px;
}

.install-step p {
  font-size: 0.82rem;
  color: var(--text-secondary);
  margin-top: 4px;
}

/* ===== FOOTER ===== */
.footer {
  padding: 80px 0 48px;
  background: var(--bg-dark);
  text-align: center;
}

.footer h2 {
  font-size: clamp(1.8rem, 3.5vw, 2.5rem);
  font-weight: 900;
  color: var(--text-light);
  letter-spacing: -1px;
}

.footer-sub {
  font-size: 1rem;
  color: var(--text-light-secondary);
  margin-top: 12px;
  margin-bottom: 32px;
  line-height: 1.65;
}

.footer .btn-primary {
  background: var(--accent);
  color: white;
}
.footer .btn-primary:hover {
  background: var(--accent-hover);
}

.footer .btn-ghost {
  border-color: rgba(255,255,255,0.15);
  color: var(--text-light-secondary);
}
.footer .btn-ghost:hover {
  border-color: rgba(255,255,255,0.3);
  color: var(--text-light);
  background: rgba(255,255,255,0.04);
}

.footer-credits {
  margin-top: 48px;
  font-size: 0.75rem;
  color: rgba(255,255,255,0.25);
  letter-spacing: 0.02em;
}

/* ===== SCROLL ANIMATIONS ===== */
.card, .feature, .demo-card, .trust-item, .install-step, .message-studio {
  opacity: 0;
  transform: translateY(20px);
  animation: fadeUp 0.5s ease forwards;
}

@keyframes fadeUp {
  to { opacity: 1; transform: translateY(0); }
}

/* Stagger cards */
.grid-3 .card:nth-child(1) { animation-delay: 0.1s; }
.grid-3 .card:nth-child(2) { animation-delay: 0.2s; }
.grid-3 .card:nth-child(3) { animation-delay: 0.3s; }

.features-grid .feature:nth-child(1) { animation-delay: 0.1s; }
.features-grid .feature:nth-child(2) { animation-delay: 0.15s; }
.features-grid .feature:nth-child(3) { animation-delay: 0.2s; }
.features-grid .feature:nth-child(4) { animation-delay: 0.25s; }

.demo-grid .demo-card:nth-child(1) { animation-delay: 0.1s; }
.demo-grid .demo-card:nth-child(2) { animation-delay: 0.2s; }
.demo-grid .demo-card:nth-child(3) { animation-delay: 0.3s; }

/* ===== RESPONSIVE ===== */
@media (max-width: 900px) {
  .hero { padding: 96px 0 56px; }
  .hero-grid { grid-template-columns: 1fr; gap: 40px; }
  .hero-visual { order: -1; }
  .hero-stats { gap: 20px; flex-wrap: wrap; }
  .grid-3, .demo-grid, .features-grid, .trust-grid, .install-grid { grid-template-columns: 1fr; }
  .steps-row { flex-direction: column; }
  .step-line { width: 2px; height: 24px; background: linear-gradient(180deg, var(--accent), rgba(5,150,105,0.2)); }
  .nav-links a:not(.nav-cta) { display: none; }
  .trust-item.full-width { grid-column: 1; }
  .studio-variants { flex-wrap: wrap; }
  .section { padding: 64px 0; }
  .demo-embed { border-radius: 12px; }
  .demo-embed iframe { height: 400px; }
}

@media (max-width: 480px) {
  h1 { font-size: 2rem; }
  .hero-stats { flex-direction: column; gap: 12px; }
  .message-studio { padding: 20px; }
  .demo-embed iframe { height: 320px; }
}

/* ===== Interactive Demo Embed ===== */
.demo-embed {
  max-width: 1100px;
  margin: 0 auto 0;
  border-radius: 16px;
  overflow: hidden;
  box-shadow: 0 30px 60px rgba(0,0,0,0.3), 0 0 0 1px rgba(5,150,105,0.15);
}
.demo-embed iframe {
  width: 100%;
  height: 620px;
  border: none;
  display: block;
}
.demo-fullscreen-link {
  color: var(--accent);
  font-size: 0.85rem;
  font-weight: 600;
  text-decoration: none;
  border-bottom: 1px dashed var(--accent);
  transition: opacity 0.2s;
}
.demo-fullscreen-link:hover { opacity: 0.7; }