/* ===== Pixi Co. — Mobile-First Design ===== */
/* Base: iPhone 17 (393px). Desktop via @media (min-width: 768px) */

:root {
  --bg: #ffffff;
  --fg: #0a0a0a;
  --fg-dim: #6b6b6b;
  --fg-mid: #444444;
  --accent: #000000;
  --border: rgba(0, 0, 0, 0.1);
  --surface: rgba(0, 0, 0, 0.03);
  --font-headline: 'Playfair Display', Georgia, serif;
  --font-mono: 'JetBrains Mono', 'Courier New', monospace;
}

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

html {
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
  scroll-behavior: smooth;
  scroll-padding-top: 4rem;
}

body {
  background-color: var(--bg);
  color: var(--fg);
  font-family: var(--font-mono);
  font-size: 0.875rem;
  line-height: 1.7;
  overflow-x: hidden;
}

::selection {
  background-color: var(--fg);
  color: var(--bg);
}

/* ===== Grid Overlay ===== */
.grid-overlay {
  position: fixed;
  inset: 0;
  background-image:
    linear-gradient(rgba(0, 0, 0, 0.04) 1px, transparent 1px),
    linear-gradient(90deg, rgba(0, 0, 0, 0.04) 1px, transparent 1px);
  background-size: 40px 40px;
  pointer-events: none;
  z-index: 0;
}

/* ===== Particles ===== */
.particles {
  position: fixed;
  inset: 0;
  pointer-events: none;
  z-index: 0;
  overflow: hidden;
}

.particle {
  position: absolute;
  width: 1.5px;
  height: 1.5px;
  background: var(--fg);
  opacity: 0;
  animation: drift linear infinite;
}

.particle:nth-child(1) { left: 8%;  top: 20%; animation-duration: 12s; animation-delay: 0s; }
.particle:nth-child(2) { left: 15%; top: 60%; animation-duration: 18s; animation-delay: 2s; }
.particle:nth-child(3) { left: 30%; top: 40%; animation-duration: 20s; animation-delay: 1s; }
.particle:nth-child(4) { left: 45%; top: 75%; animation-duration: 15s; animation-delay: 4s; }
.particle:nth-child(5) { left: 55%; top: 15%; animation-duration: 14s; animation-delay: 3s; }
.particle:nth-child(6) { left: 65%; top: 50%; animation-duration: 16s; animation-delay: 5s; }
.particle:nth-child(7) { left: 78%; top: 70%; animation-duration: 22s; animation-delay: 0.5s; }
.particle:nth-child(8) { left: 88%; top: 25%; animation-duration: 13s; animation-delay: 6s; }

@keyframes drift {
  0%   { opacity: 0;    transform: translateY(0) translateX(0); }
  10%  { opacity: 0.12; }
  50%  { opacity: 0.06; transform: translateY(-30vh) translateX(15px); }
  90%  { opacity: 0.12; }
  100% { opacity: 0;    transform: translateY(-60vh) translateX(-8px); }
}

/* ===== Container ===== */
.container {
  position: relative;
  z-index: 2;
  max-width: 960px;
  margin: 0 auto;
  padding: 0 1.25rem;
}

/* ===== Nav ===== */
.nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  padding: 1rem 0;
  background: rgba(255, 255, 255, 0.9);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border);
}

.nav-inner {
  max-width: 960px;
  margin: 0 auto;
  padding: 0 1.25rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.logo {
  font-family: var(--font-mono);
  font-size: 0.8125rem;
  font-weight: 700;
  letter-spacing: 0.3em;
  text-transform: uppercase;
  color: var(--fg-mid);
}

.logo span {
  color: var(--fg);
}

.nav-cta {
  font-family: var(--font-mono);
  font-size: 0.6875rem;
  color: var(--fg-dim);
  text-decoration: none;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  padding: 0.5rem 1.25rem;
  border: 1px solid var(--border);
  border-radius: 2px;
  transition: border-color 0.3s, color 0.3s;
}

.nav-cta:hover {
  border-color: var(--fg-mid);
  color: var(--fg);
}

/* ===== Hero ===== */
.hero {
  min-height: 100svh;
  display: flex;
  align-items: center;
  justify-content: center;
  text-align: center;
  padding: 5rem 0 4rem;
}

.hero-tag {
  font-family: var(--font-mono);
  font-size: 0.625rem;
  color: var(--fg-dim);
  letter-spacing: 0.3em;
  text-transform: uppercase;
  margin-bottom: 1.5rem;
  animation: fadeIn 1s ease-out 0.2s both;
}

.heading {
  font-family: var(--font-headline);
  font-weight: 900;
  font-size: 2.75rem;
  line-height: 1.05;
  letter-spacing: -0.02em;
  color: var(--accent);
  margin-bottom: 1.25rem;
  animation: fadeIn 1s ease-out 0.5s both;
}

.subtitle {
  font-family: var(--font-mono);
  font-size: 0.8125rem;
  font-weight: 400;
  color: var(--fg-mid);
  letter-spacing: 0.01em;
  line-height: 1.8;
  max-width: 360px;
  margin: 0 auto 2.5rem;
  animation: fadeIn 1s ease-out 0.8s both;
}

.hero-cta {
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
  align-items: center;
  animation: fadeIn 1s ease-out 1.1s both;
}

/* ===== Buttons ===== */
.btn {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 0.75rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  text-decoration: none;
  padding: 0.875rem 2.5rem;
  border-radius: 2px;
  transition: all 0.3s;
  cursor: pointer;
  width: 100%;
  max-width: 280px;
  text-align: center;
}

.btn-primary {
  background: var(--fg);
  color: var(--bg);
  border: 1px solid var(--fg);
}

.btn-primary:hover {
  background: transparent;
  color: var(--fg);
}

.btn-ghost {
  background: transparent;
  color: var(--fg-mid);
  border: 1px solid var(--border);
}

.btn-ghost:hover {
  color: var(--fg);
  border-color: var(--fg-mid);
}

.btn-lg {
  padding: 1rem 2.5rem;
  font-size: 0.8125rem;
}

/* ===== Sections ===== */
.section {
  padding: 4.5rem 0;
  position: relative;
  z-index: 2;
}

.section-alt {
  background: transparent;
  border-top: 1px solid var(--border);
  border-bottom: 1px solid var(--border);
}

.section-tag {
  font-family: var(--font-mono);
  font-size: 0.625rem;
  color: var(--fg-dim);
  letter-spacing: 0.3em;
  text-transform: uppercase;
  margin-bottom: 1rem;
}

.section-heading {
  font-family: var(--font-headline);
  font-weight: 900;
  font-size: 2rem;
  line-height: 1.15;
  letter-spacing: -0.01em;
  color: var(--accent);
  margin-bottom: 1rem;
}

.section-sub {
  font-family: var(--font-mono);
  font-size: 0.8125rem;
  color: var(--fg-mid);
  line-height: 1.8;
  margin-bottom: 2.5rem;
}

/* ===== Problem Grid ===== */
.problem-grid {
  display: flex;
  flex-direction: column;
  gap: 1rem;
  margin-top: 2.5rem;
}

.problem-card {
  padding: 1.5rem;
  border: 1px solid var(--border);
  border-radius: 2px;
}

.problem-number {
  font-family: var(--font-mono);
  font-size: 0.625rem;
  color: var(--fg-dim);
  letter-spacing: 0.2em;
  margin-bottom: 0.75rem;
}

.problem-card h3 {
  font-family: var(--font-mono);
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--fg);
  margin-bottom: 0.5rem;
  line-height: 1.4;
}

.problem-card p {
  font-size: 0.75rem;
  color: var(--fg-dim);
  line-height: 1.7;
}

/* ===== Approach Steps ===== */
.approach-steps {
  display: flex;
  flex-direction: column;
}

.step {
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
  padding: 1.75rem 0;
  border-bottom: 1px solid var(--border);
}

.step:first-child {
  border-top: 1px solid var(--border);
}

.step-num {
  font-family: var(--font-mono);
  font-size: 0.625rem;
  color: var(--fg-dim);
  letter-spacing: 0.2em;
}

.step-content h3 {
  font-family: var(--font-headline);
  font-size: 1.375rem;
  font-weight: 700;
  color: var(--accent);
  margin-bottom: 0.5rem;
}

.step-content p {
  font-size: 0.75rem;
  color: var(--fg-mid);
  line-height: 1.8;
}

/* ===== Services Grid ===== */
.services-grid {
  display: flex;
  flex-direction: column;
  gap: 1rem;
  margin-top: 2.5rem;
}

.service-card {
  padding: 1.5rem;
  border: 1px solid var(--border);
  border-radius: 2px;
}

.service-icon {
  color: var(--fg-dim);
  margin-bottom: 1rem;
}

.service-card h3 {
  font-family: var(--font-mono);
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--fg);
  margin-bottom: 0.5rem;
}

.service-card p {
  font-size: 0.75rem;
  color: var(--fg-dim);
  line-height: 1.7;
}

/* ===== CTA Section ===== */
.section-cta {
  text-align: center;
  padding: 5rem 0;
  background: transparent;
  border-top: 1px solid var(--border);
}

.section-cta .section-heading {
  margin-bottom: 0.75rem;
}

.section-cta .section-sub {
  margin: 0 auto 2.5rem;
  max-width: 320px;
}

.cta-actions {
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
  align-items: center;
  margin-bottom: 1.5rem;
}

.cta-note {
  font-family: var(--font-mono);
  font-size: 0.6875rem;
  color: var(--fg-dim);
  letter-spacing: 0.03em;
}

/* ===== Footer ===== */
.footer {
  position: relative;
  z-index: 2;
  border-top: 1px solid var(--border);
  padding: 2rem 0;
}

.footer-inner {
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
  margin-bottom: 1.5rem;
}

.footer-brand p {
  font-size: 0.6875rem;
  color: var(--fg-dim);
  margin-top: 0.375rem;
}

.footer-links {
  display: flex;
  gap: 1.5rem;
}

.footer-links a {
  font-family: var(--font-mono);
  font-size: 0.6875rem;
  color: var(--fg-dim);
  text-decoration: none;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  transition: color 0.3s;
}

.footer-links a:hover {
  color: var(--fg);
}

.footer-bottom {
  padding-top: 1.5rem;
  border-top: 1px solid var(--border);
}

.footer-bottom span {
  font-family: var(--font-mono);
  font-size: 0.625rem;
  color: var(--fg-dim);
  letter-spacing: 0.1em;
  text-transform: uppercase;
}

/* ===== Animations ===== */
@keyframes fadeIn {
  0%   { opacity: 0; transform: translateY(12px); }
  100% { opacity: 1; transform: translateY(0); }
}

/* ===== Desktop (768px+) ===== */
@media (min-width: 768px) {
  .container {
    padding: 0 2rem;
  }

  .heading {
    font-size: clamp(3rem, 7vw, 5rem);
  }

  .subtitle {
    max-width: 560px;
    font-size: 0.875rem;
  }

  .hero-cta {
    flex-direction: row;
  }

  .btn {
    width: auto;
    max-width: none;
  }

  .section {
    padding: 7rem 0;
  }

  .section-heading {
    font-size: clamp(2rem, 4.5vw, 3rem);
  }

  .problem-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 1.5rem;
  }

  .step {
    flex-direction: row;
    gap: 2.5rem;
  }

  .step-num {
    min-width: 3rem;
    padding-top: 0.25rem;
  }

  .step-content p {
    max-width: 520px;
  }

  .services-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 1.5rem;
  }

  .service-card {
    padding: 2.5rem;
  }

  .section-cta {
    padding: 8rem 0;
  }

  .section-cta .section-sub {
    max-width: 480px;
  }

  .cta-actions {
    flex-direction: row;
    justify-content: center;
  }

  .footer-inner {
    flex-direction: row;
    justify-content: space-between;
    align-items: flex-start;
  }
}