/* ============================================================
   Archtone Landing Page — styles.css
   Dark theme matching Neural DSP aesthetic. Mobile-first.
   WCAG 2.1 AA compliant.
   ============================================================ */

/* --- Google Fonts ----------------------------------------- */
@import url('https://fonts.googleapis.com/css2?family=Inter:wght@400;500;600;700&family=JetBrains+Mono:wght@400;500&display=swap');

/* --- Design Tokens ---------------------------------------- */
:root {
  /* Brand colors */
  --color-bg:            #0D0D0D;
  --color-surface:       #1A1A2E;
  --color-card:          #16213E;
  --color-accent:        #E94560;
  --color-accent-hover:  #C73652;
  --color-accent-glow:   rgba(233, 69, 96, 0.22);
  --color-accent-subtle: rgba(233, 69, 96, 0.1);

  /* Text */
  --color-text-primary:  #FFFFFF;
  --color-text-body:     #B0B0B0;
  --color-text-muted:    #8E8E93;

  /* Borders */
  --color-border:        rgba(255, 255, 255, 0.08);
  --color-border-card:   rgba(255, 255, 255, 0.06);
  --color-border-accent: rgba(233, 69, 96, 0.35);

  /* Semantic */
  --color-success:       #6FCF97;
  --color-success-subtle: rgba(111, 207, 151, 0.12);

  /* Typography */
  --font-sans: 'Inter', system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  --font-mono: 'JetBrains Mono', 'Fira Code', 'Courier New', monospace;

  /* Spacing (4px base grid) */
  --space-1:  0.25rem;   /*  4px */
  --space-2:  0.5rem;    /*  8px */
  --space-3:  0.75rem;   /* 12px */
  --space-4:  1rem;      /* 16px */
  --space-5:  1.25rem;   /* 20px */
  --space-6:  1.5rem;    /* 24px */
  --space-8:  2rem;      /* 32px */
  --space-10: 2.5rem;    /* 40px */
  --space-12: 3rem;      /* 48px */
  --space-16: 4rem;      /* 64px */
  --space-20: 5rem;      /* 80px */
  --space-24: 6rem;      /* 96px */

  /* Border radius */
  --radius-sm:   4px;
  --radius:      8px;
  --radius-lg:   12px;
  --radius-xl:   16px;
  --radius-full: 9999px;

  /* Shadows */
  --shadow-card:   0 4px 24px rgba(0, 0, 0, 0.5);
  --shadow-accent: 0 0 40px var(--color-accent-glow);

  /* Layout */
  --site-max-width: 1200px;
  --nav-height:      64px;
}

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

html {
  font-size: 16px;
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}

body {
  background-color: var(--color-bg);
  color: var(--color-text-body);
  font-family: var(--font-sans);
  line-height: 1.6;
  min-height: 100vh;
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

img,
svg {
  display: block;
  max-width: 100%;
}

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

ul {
  list-style: none;
}

button {
  font-family: inherit;
  cursor: pointer;
  border: none;
  background: none;
}

/* Focus indicator — never suppress without replacement */
:focus-visible {
  outline: 2px solid var(--color-accent);
  outline-offset: 3px;
  border-radius: var(--radius-sm);
}

/* --- Skip link (accessibility) ---------------------------- */
.skip-link {
  position: absolute;
  top: -100%;
  left: var(--space-4);
  padding: var(--space-2) var(--space-5);
  background: var(--color-accent);
  color: var(--color-text-primary);
  font-size: 0.9375rem;
  font-weight: 600;
  border-radius: var(--radius-lg);
  z-index: 9999;
  transition: top 0.2s;
  text-decoration: none;
}

.skip-link:focus {
  top: var(--space-4);
}

/* --- Layout container ------------------------------------- */
.container {
  width: 100%;
  max-width: var(--site-max-width);
  margin-inline: auto;
  padding-inline: var(--space-5);
}

@media (min-width: 768px) {
  .container {
    padding-inline: var(--space-8);
  }
}

@media (min-width: 1024px) {
  .container {
    padding-inline: var(--space-12);
  }
}

/* --- Utility ---------------------------------------------- */
.visually-hidden {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

/* --- Typography ------------------------------------------- */
h1, h2, h3, h4 {
  color: var(--color-text-primary);
  font-family: var(--font-sans);
  font-weight: 700;
  line-height: 1.2;
  letter-spacing: -0.02em;
}

h1 { font-size: clamp(2.25rem, 5vw, 3.5rem); }
h2 { font-size: clamp(1.75rem, 3.5vw, 2.25rem); }
h3 { font-size: 1.125rem; font-weight: 600; letter-spacing: -0.01em; }

p {
  color: var(--color-text-body);
  line-height: 1.7;
  max-width: 68ch;
}

code,
.mono {
  font-family: var(--font-mono);
  font-size: 0.875em;
}

.section-eyebrow {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 0.6875rem;
  font-weight: 500;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--color-accent);
  margin-bottom: var(--space-3);
}

.section-header {
  margin-bottom: var(--space-12);
}

.section-header.centered {
  text-align: center;
  display: flex;
  flex-direction: column;
  align-items: center;
}

.section-header p {
  margin-top: var(--space-4);
  font-size: 1.0625rem;
  color: var(--color-text-body);
}

/* --- Buttons ---------------------------------------------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-2);
  padding: 13px var(--space-6);
  font-size: 0.9375rem;
  font-weight: 600;
  border-radius: var(--radius-lg);
  min-height: 48px;
  white-space: nowrap;
  cursor: pointer;
  text-decoration: none;
  transition: background-color 0.18s ease, box-shadow 0.18s ease, transform 0.1s ease;
  border: none;
}

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

.btn-primary:hover {
  background-color: var(--color-accent-hover);
  box-shadow: 0 4px 20px var(--color-accent-glow);
}

.btn-primary:active {
  transform: scale(0.98);
}

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

.btn-ghost:hover {
  background-color: rgba(255, 255, 255, 0.05);
  border-color: rgba(255, 255, 255, 0.14);
}

/* --- Store badge links ------------------------------------ */
.store-badges {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-3);
  align-items: center;
}

.badge-link {
  display: inline-flex;
  align-items: center;
  gap: var(--space-3);
  padding: 10px 18px;
  background-color: rgba(255, 255, 255, 0.05);
  border: 1px solid rgba(255, 255, 255, 0.1);
  border-radius: var(--radius-lg);
  color: var(--color-text-primary);
  min-height: 52px;
  transition: background-color 0.18s ease, border-color 0.18s ease;
  text-decoration: none;
}

.badge-link:hover {
  background-color: rgba(255, 255, 255, 0.09);
  border-color: rgba(255, 255, 255, 0.18);
}

.badge-icon {
  font-size: 1.625rem;
  line-height: 1;
  flex-shrink: 0;
}

.badge-text {
  display: flex;
  flex-direction: column;
  line-height: 1.2;
}

.badge-text .badge-subtitle {
  font-size: 0.6875rem;
  color: var(--color-text-muted);
  font-weight: 400;
}

.badge-text .badge-store {
  font-size: 0.9375rem;
  font-weight: 600;
  color: var(--color-text-primary);
}

/* --- Site navigation -------------------------------------- */
.site-nav {
  position: sticky;
  top: 0;
  z-index: 100;
  background-color: rgba(26, 26, 46, 0.88);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  border-bottom: 1px solid var(--color-border);
}

.nav-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: var(--nav-height);
}

.nav-logo {
  font-size: 1.25rem;
  font-weight: 800;
  color: var(--color-text-primary);
  letter-spacing: -0.03em;
  text-decoration: none;
  transition: opacity 0.15s ease;
}

.nav-logo:hover {
  opacity: 0.85;
}

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

.nav-links {
  display: none;
  align-items: center;
  gap: var(--space-6);
}

@media (min-width: 768px) {
  .nav-links {
    display: flex;
  }
}

.nav-links a {
  font-size: 0.9rem;
  font-weight: 500;
  color: var(--color-text-body);
  transition: color 0.15s ease;
}

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

.nav-cta {
  display: none;
}

@media (min-width: 768px) {
  .nav-cta {
    display: inline-flex;
  }
}

/* --- Hero section ----------------------------------------- */
.hero {
  background-color: var(--color-surface);
  padding-block: var(--space-24) var(--space-20);
  position: relative;
  overflow: hidden;
}

/* Radial glow effect behind hero */
.hero::before {
  content: '';
  position: absolute;
  top: -10%;
  left: 50%;
  transform: translateX(-50%);
  width: 900px;
  height: 700px;
  background: radial-gradient(
    ellipse at center top,
    rgba(233, 69, 96, 0.14) 0%,
    transparent 68%
  );
  pointer-events: none;
}

.hero-inner {
  position: relative;
  z-index: 1;
  display: flex;
  flex-direction: column;
  align-items: center;
  text-align: center;
  gap: var(--space-6);
}

.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
  padding: 6px var(--space-4);
  background-color: var(--color-accent-subtle);
  border: 1px solid rgba(233, 69, 96, 0.28);
  border-radius: var(--radius-full);
  font-family: var(--font-mono);
  font-size: 0.6875rem;
  font-weight: 500;
  color: var(--color-accent);
  letter-spacing: 0.1em;
  text-transform: uppercase;
}

.hero-badge-dot {
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background-color: var(--color-accent);
  flex-shrink: 0;
}

.hero-title {
  font-size: clamp(3rem, 8vw, 5.5rem);
  font-weight: 800;
  letter-spacing: -0.04em;
  line-height: 1.0;
  color: var(--color-text-primary);
}

.hero-title .accent {
  color: var(--color-accent);
}

.hero-tagline {
  font-size: clamp(1.0625rem, 2.5vw, 1.25rem);
  font-weight: 500;
  color: var(--color-text-primary);
  opacity: 0.8;
  max-width: 52ch;
  line-height: 1.5;
}

.hero-subtitle {
  font-size: 1rem;
  color: var(--color-text-body);
  max-width: 46ch;
  line-height: 1.75;
}

.hero-actions {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: var(--space-5);
  margin-top: var(--space-2);
  width: 100%;
}

@media (min-width: 480px) {
  .hero-actions {
    flex-direction: row;
    justify-content: center;
    flex-wrap: wrap;
  }
}

/* --- How It Works section --------------------------------- */
.how-it-works {
  padding-block: var(--space-24);
  background-color: var(--color-bg);
}

.steps-grid {
  display: grid;
  gap: var(--space-5);
}

@media (min-width: 768px) {
  .steps-grid {
    grid-template-columns: repeat(3, 1fr);
    gap: var(--space-6);
    align-items: start;
  }
}

.step-card {
  position: relative;
  padding: var(--space-8) var(--space-6);
  background-color: var(--color-card);
  border: 1px solid var(--color-border-card);
  border-radius: var(--radius-xl);
  transition: border-color 0.2s ease;
}

.step-card:hover {
  border-color: rgba(233, 69, 96, 0.22);
}

.step-number {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 42px;
  height: 42px;
  border-radius: var(--radius);
  background-color: var(--color-accent-subtle);
  border: 1px solid rgba(233, 69, 96, 0.22);
  font-family: var(--font-mono);
  font-size: 0.875rem;
  font-weight: 700;
  color: var(--color-accent);
  margin-bottom: var(--space-5);
}

.step-title {
  font-size: 1.0625rem;
  font-weight: 600;
  color: var(--color-text-primary);
  margin-bottom: var(--space-3);
  letter-spacing: -0.01em;
}

.step-description {
  font-size: 0.9375rem;
  color: var(--color-text-body);
  line-height: 1.65;
}

/* Arrow connectors between steps on desktop */
@media (min-width: 768px) {
  .step-card:not(:last-child)::after {
    content: '→';
    position: absolute;
    top: 38px;
    right: -22px;
    font-size: 1.125rem;
    color: var(--color-accent);
    opacity: 0.35;
    pointer-events: none;
    z-index: 1;
  }
}

/* --- Features section ------------------------------------- */
.features {
  padding-block: var(--space-24);
  background-color: var(--color-surface);
}

.features-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--space-4);
}

@media (min-width: 1024px) {
  .features-grid {
    grid-template-columns: repeat(3, 1fr);
    gap: var(--space-5);
  }
}

.feature-card {
  display: flex;
  flex-direction: column;
  gap: var(--space-3);
  padding: var(--space-6) var(--space-5);
  background-color: var(--color-card);
  border: 1px solid var(--color-border-card);
  border-radius: var(--radius-xl);
  transition: border-color 0.2s ease, transform 0.2s ease;
}

.feature-card:hover {
  border-color: rgba(255, 255, 255, 0.12);
  transform: translateY(-2px);
}

.feature-icon {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 48px;
  height: 48px;
  border-radius: var(--radius);
  background-color: var(--color-accent-subtle);
  font-size: 1.375rem;
  flex-shrink: 0;
}

.feature-title {
  font-size: 0.9375rem;
  font-weight: 600;
  color: var(--color-text-primary);
  line-height: 1.35;
}

.feature-description {
  font-size: 0.875rem;
  color: var(--color-text-body);
  line-height: 1.65;
}

.feature-tag {
  display: inline-flex;
  align-items: center;
  padding: 2px 8px;
  border-radius: var(--radius-sm);
  font-family: var(--font-mono);
  font-size: 0.6rem;
  font-weight: 600;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  align-self: flex-start;
}

.feature-tag.premium {
  background-color: rgba(233, 69, 96, 0.14);
  color: var(--color-accent);
  border: 1px solid rgba(233, 69, 96, 0.22);
}

.feature-tag.free {
  background-color: var(--color-success-subtle);
  color: var(--color-success);
  border: 1px solid rgba(111, 207, 151, 0.2);
}

/* --- Pricing section -------------------------------------- */
.pricing {
  padding-block: var(--space-24);
  background-color: var(--color-bg);
}

.pricing-grid {
  display: grid;
  gap: var(--space-6);
  max-width: 860px;
  margin-inline: auto;
}

@media (min-width: 768px) {
  .pricing-grid {
    grid-template-columns: repeat(2, 1fr);
    align-items: start;
    gap: var(--space-8);
  }
}

.pricing-card {
  display: flex;
  flex-direction: column;
  gap: var(--space-6);
  padding: var(--space-8) var(--space-6);
  background-color: var(--color-card);
  border: 1px solid var(--color-border-card);
  border-radius: var(--radius-xl);
}

.pricing-card.premium {
  border-color: var(--color-border-accent);
  box-shadow: var(--shadow-accent);
  position: relative;
}

.pricing-card.premium::before {
  content: 'Most Popular';
  position: absolute;
  top: -13px;
  left: 50%;
  transform: translateX(-50%);
  padding: 3px 16px;
  background-color: var(--color-accent);
  color: #fff;
  font-size: 0.6875rem;
  font-weight: 700;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  border-radius: var(--radius-full);
  white-space: nowrap;
}

.pricing-tier {
  font-family: var(--font-mono);
  font-size: 0.6875rem;
  font-weight: 500;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--color-text-muted);
}

.pricing-price {
  display: flex;
  align-items: baseline;
  gap: var(--space-1);
  flex-wrap: wrap;
}

.pricing-amount {
  font-size: 2.75rem;
  font-weight: 800;
  color: var(--color-text-primary);
  letter-spacing: -0.04em;
  line-height: 1;
}

.pricing-period {
  font-size: 1rem;
  color: var(--color-text-muted);
  font-weight: 400;
}

.pricing-annual-note {
  font-family: var(--font-mono);
  font-size: 0.8125rem;
  color: var(--color-text-muted);
}

.pricing-annual-note strong {
  color: var(--color-success);
  font-weight: 500;
}

.pricing-divider {
  border: none;
  border-top: 1px solid var(--color-border);
}

.pricing-features {
  display: flex;
  flex-direction: column;
  gap: var(--space-3);
}

.pricing-features li {
  display: flex;
  align-items: flex-start;
  gap: var(--space-3);
  font-size: 0.9375rem;
  color: var(--color-text-body);
  line-height: 1.5;
}

.pricing-features li .check-icon {
  flex-shrink: 0;
  width: 18px;
  height: 18px;
  display: flex;
  align-items: center;
  justify-content: center;
  margin-top: 1px;
  font-size: 0.875rem;
}

.check-free  { color: var(--color-success); }
.check-prem  { color: var(--color-accent); }

.pricing-cta {
  margin-top: auto;
}

.pricing-cta .btn {
  width: 100%;
}

/* --- Footer ----------------------------------------------- */
.site-footer {
  background-color: var(--color-surface);
  border-top: 1px solid var(--color-border);
  padding-block: var(--space-16) var(--space-10);
}

.footer-inner {
  display: flex;
  flex-direction: column;
  gap: var(--space-10);
}

@media (min-width: 768px) {
  .footer-inner {
    flex-direction: row;
    justify-content: space-between;
    gap: var(--space-12);
  }
}

.footer-brand {
  display: flex;
  flex-direction: column;
  gap: var(--space-3);
  max-width: 260px;
}

.footer-logo {
  display: inline-flex;
  font-size: 1.25rem;
  font-weight: 800;
  color: var(--color-text-primary);
  letter-spacing: -0.03em;
  text-decoration: none;
}

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

.footer-tagline {
  font-size: 0.875rem;
  color: var(--color-text-muted);
  line-height: 1.55;
}

.footer-links-col {
  display: flex;
  flex-direction: column;
  gap: var(--space-4);
}

.footer-links-heading {
  font-size: 0.6875rem;
  font-weight: 600;
  font-family: var(--font-mono);
  color: var(--color-text-muted);
  text-transform: uppercase;
  letter-spacing: 0.12em;
}

.footer-links-col ul {
  display: flex;
  flex-direction: column;
  gap: var(--space-2);
}

.footer-links-col a {
  font-size: 0.9375rem;
  color: var(--color-text-body);
  transition: color 0.15s ease;
}

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

.footer-bottom {
  margin-top: var(--space-10);
  padding-top: var(--space-6);
  border-top: 1px solid var(--color-border);
  display: flex;
  flex-direction: column;
  gap: var(--space-4);
  align-items: flex-start;
}

@media (min-width: 768px) {
  .footer-bottom {
    flex-direction: row;
    align-items: center;
    justify-content: space-between;
  }
}

.footer-copy {
  font-size: 0.8125rem;
  color: var(--color-text-muted);
  line-height: 1.5;
}

.footer-store-badges {
  display: flex;
  gap: var(--space-2);
  flex-wrap: wrap;
}

.footer-badge {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
  padding: 10px 14px;
  background-color: rgba(255, 255, 255, 0.04);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  font-size: 0.8125rem;
  font-weight: 500;
  color: var(--color-text-body);
  min-height: 44px;
  transition: background-color 0.15s ease, color 0.15s ease;
  text-decoration: none;
}

.footer-badge:hover {
  background-color: rgba(255, 255, 255, 0.08);
  color: var(--color-text-primary);
}

.footer-badge .badge-icon-sm {
  font-size: 1rem;
}

/* --- Scroll reveal animations ----------------------------- */
@media (prefers-reduced-motion: no-preference) {
  .reveal {
    opacity: 0;
    transform: translateY(18px);
    transition: opacity 0.55s ease, transform 0.55s ease;
  }

  .reveal.is-visible {
    opacity: 1;
    transform: translateY(0);
  }

  .reveal-delay-1 { transition-delay: 0.08s; }
  .reveal-delay-2 { transition-delay: 0.18s; }
  .reveal-delay-3 { transition-delay: 0.28s; }
}

/* Always visible when reduced motion or JS unavailable */
@media (prefers-reduced-motion: reduce) {
  .reveal { opacity: 1; transform: none; }
}