/* ===========================
   RESET & BASE
   =========================== */

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

html {
  scroll-behavior: smooth;
}

:root {
  --bg:            #0a0a0f;
  --bg-surface:    #13131d;
  --bg-elevated:   #1a1a28;
  --border:        #1f1f30;
  --accent:        #7c6fff;
  --accent-hover:  #9b95ff;
  --accent-glow:   rgba(124, 111, 255, 0.15);
  --text-primary:  #eeeef5;
  --text-secondary:#7878a0;
  --text-tertiary: #4a4a6a;
  --radius-sm:     8px;
  --radius:        12px;
  --radius-lg:     16px;
  --shadow:        0 4px 32px rgba(0, 0, 0, 0.5);
  --shadow-accent: 0 0 60px rgba(124, 111, 255, 0.12), 0 8px 48px rgba(0, 0, 0, 0.7);
}

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

img {
  max-width: 100%;
  height: auto;
  display: block;
}

a {
  color: inherit;
  text-decoration: none;
}

ul {
  list-style: none;
}

.container {
  max-width: 1100px;
  margin: 0 auto;
  padding: 0 24px;
}

/* ===========================
   NAV
   =========================== */

.nav {
  position: sticky;
  top: 0;
  z-index: 100;
  padding: 16px 0;
  transition: background 0.3s ease, border-color 0.3s ease, box-shadow 0.3s ease;
  border-bottom: 1px solid transparent;
}

.nav--scrolled {
  background: rgba(10, 10, 15, 0.85);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border-bottom-color: var(--border);
  box-shadow: 0 1px 24px rgba(0, 0, 0, 0.35);
}

.nav-inner {
  display: flex;
  align-items: center;
  gap: 32px;
}

.nav-logo {
  display: flex;
  align-items: center;
  gap: 10px;
  flex-shrink: 0;
}

.logo-icon {
  width: 32px;
  height: 32px;
  flex-shrink: 0;
}

.logo-text {
  font-size: 1.0625rem;
  font-weight: 700;
  color: var(--text-primary);
  letter-spacing: -0.01em;
}

.nav-links {
  display: flex;
  gap: 28px;
  margin-left: 8px;
}

.nav-links a {
  font-size: 0.9375rem;
  font-weight: 500;
  color: var(--text-secondary);
  transition: color 0.2s ease;
}

.nav-links a:hover {
  color: var(--text-primary);
}

.nav-cta {
  margin-left: auto;
}

/* ===========================
   BUTTONS
   =========================== */

.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 10px 20px;
  border-radius: var(--radius-sm);
  font-family: inherit;
  font-size: 0.9375rem;
  font-weight: 600;
  cursor: pointer;
  border: none;
  text-decoration: none;
  transition: background 0.2s ease, box-shadow 0.2s ease, border-color 0.2s ease, color 0.2s ease;
  white-space: nowrap;
  line-height: 1;
}

.btn-primary {
  background: var(--accent);
  color: #fff;
}

.btn-primary:hover {
  background: var(--accent-hover);
  box-shadow: 0 4px 24px rgba(124, 111, 255, 0.4);
}

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

.btn-secondary:hover {
  border-color: var(--accent);
  color: var(--accent);
}

.btn-sm {
  padding: 8px 16px;
  font-size: 0.875rem;
}

.btn-large {
  padding: 14px 28px;
  font-size: 1.0625rem;
}

.btn-os-icon {
  width: 18px;
  height: 18px;
  flex-shrink: 0;
}

.btn-large .btn-os-icon {
  width: 20px;
  height: 20px;
}

/* ===========================
   DOWNLOAD GROUP
   (wraps button + os-req + alt link)
   =========================== */

.download-group {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  gap: 12px;
}

.download-group--centered {
  align-items: center;
}

.download-group--stack {
  flex-direction: row;
  flex-wrap: wrap;
  gap: 12px;
}

.os-req {
  font-size: 0.8125rem;
  color: var(--text-tertiary);
  font-weight: 500;
}

.alt-os-link {
  font-size: 0.875rem;
  color: var(--text-secondary);
  transition: color 0.2s ease;
}

.alt-os-link:hover {
  color: var(--accent);
}

/* ===========================
   SCROLL ANIMATIONS
   =========================== */

.fade-in {
  opacity: 0;
  transform: translateY(28px);
  transition: opacity 0.65s ease, transform 0.65s ease;
}

.fade-in.visible {
  opacity: 1;
  transform: translateY(0);
}

/* Stagger feature cards */
.feature-card:nth-child(2).fade-in { transition-delay: 0.08s; }
.feature-card:nth-child(3).fade-in { transition-delay: 0.16s; }
.feature-card:nth-child(4).fade-in { transition-delay: 0.24s; }

/* Stagger screenshot figures */
.screenshot-figure:nth-child(2).fade-in { transition-delay: 0.08s; }
.screenshot-figure:nth-child(3).fade-in { transition-delay: 0.16s; }
.screenshot-figure:nth-child(4).fade-in { transition-delay: 0.24s; }

/* ===========================
   HERO
   =========================== */

.hero {
  padding: 80px 0 0;
  text-align: center;
  overflow: hidden;
}

.hero .container {
  display: flex;
  flex-direction: column;
  align-items: center;
}

.hero-content {
  max-width: 680px;
  margin-bottom: 40px;
}

.hero-headline {
  font-size: clamp(2.25rem, 5vw, 3.5rem);
  font-weight: 700;
  line-height: 1.15;
  letter-spacing: -0.025em;
  margin-bottom: 20px;
  color: var(--text-primary);
}

.hero-subhead {
  font-size: clamp(1rem, 2vw, 1.1875rem);
  color: var(--text-secondary);
  line-height: 1.7;
  margin-bottom: 36px;
  max-width: 560px;
  margin-left: auto;
  margin-right: auto;
}

.hero-cta {
  display: flex;
  justify-content: center;
}

.hero-screenshot {
  width: 100%;
  max-width: 960px;
  position: relative;
}

/* Subtle glow behind hero screenshot */
.hero-screenshot::before {
  content: '';
  position: absolute;
  bottom: -40px;
  left: 50%;
  transform: translateX(-50%);
  width: 80%;
  height: 120px;
  background: radial-gradient(ellipse at center, rgba(124, 111, 255, 0.2) 0%, transparent 70%);
  pointer-events: none;
  z-index: 0;
}

.screenshot-hero {
  width: 100%;
  border-radius: var(--radius-lg) var(--radius-lg) 0 0;
  box-shadow: var(--shadow-accent);
  border: 1px solid var(--border);
  border-bottom: none;
  position: relative;
  z-index: 1;
  /* Placeholder style — visible until real image loads */
  background: var(--bg-elevated);
  min-height: 400px;
  object-fit: cover;
  object-position: top;
}

/* ===========================
   SECTION BASE
   =========================== */

.section {
  padding: 96px 0;
}

.section-label {
  font-size: 0.8125rem;
  font-weight: 700;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: 48px;
  text-align: center;
}

/* ===========================
   PROBLEM SECTION
   =========================== */

.problem {
  background: linear-gradient(180deg, var(--bg) 0%, var(--bg-surface) 100%);
  border-top: 1px solid var(--border);
  border-bottom: 1px solid var(--border);
}

.problem-inner {
  max-width: 660px;
  margin: 0 auto;
  text-align: center;
}

.problem-text {
  font-size: 1.125rem;
  color: var(--text-secondary);
  line-height: 1.75;
  margin-bottom: 20px;
}

.problem-text--highlight {
  color: var(--text-primary);
  font-weight: 500;
  margin-bottom: 0;
}

/* ===========================
   FEATURES GRID
   =========================== */

.features {
  background: var(--bg);
}

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

.feature-card {
  background: var(--bg-surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 32px;
  transition: border-color 0.25s ease, box-shadow 0.25s ease,
              opacity 0.65s ease, transform 0.65s ease;
}

.feature-card:hover {
  border-color: rgba(124, 111, 255, 0.4);
  box-shadow: 0 0 28px rgba(124, 111, 255, 0.07);
}

.feature-icon {
  width: 44px;
  height: 44px;
  background: var(--accent-glow);
  border-radius: var(--radius-sm);
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 20px;
  color: var(--accent);
}

.feature-icon svg {
  width: 22px;
  height: 22px;
}

.feature-name {
  font-size: 1.0625rem;
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: 10px;
  letter-spacing: -0.01em;
}

.feature-desc {
  font-size: 0.9375rem;
  color: var(--text-secondary);
  line-height: 1.65;
}

/* ===========================
   SCREENSHOTS SECTION
   =========================== */

.screenshots {
  background: var(--bg-surface);
  border-top: 1px solid var(--border);
  border-bottom: 1px solid var(--border);
}

.screenshots-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 32px;
}

.screenshot-figure {
  display: flex;
  flex-direction: column;
  gap: 14px;
}

.screenshot-img {
  border-radius: var(--radius-lg);
  border: 1px solid var(--border);
  box-shadow: var(--shadow);
  width: 100%;
  /* Placeholder dimensions visible before images load */
  background: var(--bg-elevated);
  min-height: 240px;
  object-fit: cover;
  object-position: top;
}

.screenshot-figure figcaption {
  font-size: 0.875rem;
  color: var(--text-secondary);
  text-align: center;
}

/* ===========================
   DOWNLOAD CTA SECTION
   =========================== */

.download-cta {
  background: var(--bg);
  position: relative;
  overflow: hidden;
}

/* Radial glow behind CTA */
.download-cta::before {
  content: '';
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  width: 700px;
  height: 500px;
  background: radial-gradient(ellipse at center, rgba(124, 111, 255, 0.09) 0%, transparent 70%);
  pointer-events: none;
}

.download-cta-inner {
  text-align: center;
  position: relative;
  z-index: 1;
}

.download-headline {
  font-size: clamp(2rem, 4vw, 3rem);
  font-weight: 700;
  letter-spacing: -0.025em;
  line-height: 1.15;
  margin-bottom: 16px;
}

.download-subhead {
  font-size: 1.0625rem;
  color: var(--text-secondary);
  margin-bottom: 40px;
}

/* ===========================
   FOOTER
   =========================== */

.footer {
  padding: 40px 0;
  border-top: 1px solid var(--border);
}

.footer-inner {
  display: flex;
  align-items: center;
  gap: 32px;
}

.footer-links {
  display: flex;
  gap: 20px;
}

.footer-link {
  font-size: 0.875rem;
  color: var(--text-secondary);
  transition: color 0.2s ease;
}

.footer-link:hover {
  color: var(--accent);
}

.footer-copy {
  margin-left: auto;
  font-size: 0.8125rem;
  color: var(--text-tertiary);
}

/* ===========================
   RESPONSIVE
   =========================== */

@media (max-width: 768px) {
  .nav-links {
    display: none;
  }

  .hero {
    padding-top: 48px;
  }

  .section {
    padding: 64px 0;
  }

  .features-grid {
    grid-template-columns: 1fr;
  }

  .screenshots-grid {
    grid-template-columns: 1fr;
  }

  .footer-inner {
    flex-direction: column;
    align-items: flex-start;
    gap: 16px;
  }

  .footer-copy {
    margin-left: 0;
  }

  .download-group--stack {
    flex-direction: column;
  }
}

@media (max-width: 480px) {
  .container {
    padding: 0 16px;
  }

  .feature-card {
    padding: 24px;
  }
}