/* ============================================
   NEUROCISZA — Design Tokens
   ============================================ */
:root {
  /* Type scale (fluid) */
  --text-xs: clamp(0.75rem, 0.7rem + 0.25vw, 0.875rem);
  --text-sm: clamp(0.875rem, 0.8rem + 0.35vw, 1rem);
  --text-base: clamp(1rem, 0.95rem + 0.25vw, 1.125rem);
  --text-lg: clamp(1.125rem, 1rem + 0.75vw, 1.5rem);
  --text-xl: clamp(1.5rem, 1.2rem + 1.25vw, 2.25rem);
  --text-2xl: clamp(2rem, 1.2rem + 2.5vw, 3.25rem);
  --text-3xl: clamp(2.5rem, 1rem + 4vw, 4.5rem);
  --text-hero: clamp(2.5rem, 1rem + 4vw, 4.25rem);

  /* Spacing */
  --space-1: 0.25rem;
  --space-2: 0.5rem;
  --space-3: 0.75rem;
  --space-4: 1rem;
  --space-5: 1.25rem;
  --space-6: 1.5rem;
  --space-8: 2rem;
  --space-10: 2.5rem;
  --space-12: 3rem;
  --space-16: 4rem;
  --space-20: 5rem;
  --space-24: 6rem;
  --space-32: 8rem;

  /* Colors — NEUROCISZA brand: deep navy surfaces, teal primary, warm gold accent */
  --color-bg: #0b1620;
  --color-surface: #0f1e2b;
  --color-surface-2: #142838;
  --color-surface-offset: #0a1420;
  --color-divider: #1c3140;
  --color-border: #244356;

  --color-text: #eef4f2;
  --color-text-muted: #a9bcc4;
  --color-text-faint: #6d8894;
  --color-text-inverse: #0b1620;

  --color-primary: #5cb8ae;
  --color-primary-hover: #7cc9c0;
  --color-primary-active: #4a9a91;
  --color-primary-highlight: #1a3a37;

  --color-gold: #cf9f4e;
  --color-gold-hover: #e0b76b;
  --color-gold-active: #b3873c;
  --color-gold-highlight: #362a17;

  --radius-sm: 0.375rem;
  --radius-md: 0.625rem;
  --radius-lg: 1rem;
  --radius-xl: 1.5rem;
  --radius-full: 9999px;

  --transition-interactive: 180ms cubic-bezier(0.16, 1, 0.3, 1);

  --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.3);
  --shadow-md: 0 8px 24px rgba(0, 0, 0, 0.35);
  --shadow-lg: 0 20px 48px rgba(0, 0, 0, 0.45);

  --content-narrow: 640px;
  --content-default: 1120px;
  --content-wide: 1280px;

  --font-display: 'Playfair Display', Georgia, serif;
  --font-body: 'DM Sans', 'Helvetica Neue', sans-serif;
}

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

html {
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  text-rendering: optimizeLegibility;
  scroll-behavior: smooth;
  scroll-padding-top: 88px;
}

body {
  min-height: 100dvh;
  line-height: 1.6;
  font-family: var(--font-body);
  font-size: var(--text-base);
  color: var(--color-text);
  background-color: var(--color-bg);
}

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

h1, h2, h3 { text-wrap: balance; line-height: 1.15; font-family: var(--font-display); }
p, li { text-wrap: pretty; }

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

::selection { background: rgba(92, 184, 174, 0.3); color: var(--color-text); }

:focus-visible {
  outline: 2px solid var(--color-primary);
  outline-offset: 3px;
  border-radius: var(--radius-sm);
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    transition-duration: 0.01ms !important;
    scroll-behavior: auto !important;
  }
}

.skip-link {
  position: absolute;
  left: -9999px;
  top: 0;
  background: var(--color-primary);
  color: var(--color-text-inverse);
  padding: var(--space-2) var(--space-4);
  z-index: 100;
}
.skip-link:focus { left: var(--space-4); top: var(--space-4); }

.container {
  width: 100%;
  max-width: var(--content-default);
  margin-inline: auto;
  padding-inline: var(--space-6);
}
.container--narrow { max-width: var(--content-narrow); }

/* ============================================
   Header
   ============================================ */
.header {
  position: sticky;
  top: 0;
  z-index: 50;
  background: rgba(11, 22, 32, 0.85);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid transparent;
  transition: border-color var(--transition-interactive), box-shadow var(--transition-interactive);
}
.header--scrolled {
  border-bottom-color: var(--color-divider);
  box-shadow: var(--shadow-sm);
}
.header__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-6);
  padding-block: var(--space-4);
}
.brand {
  display: flex;
  align-items: center;
  gap: var(--space-2);
}
.brand__mark { border-radius: var(--radius-sm); }
.brand__name {
  font-family: var(--font-display);
  font-weight: 600;
  font-size: var(--text-lg);
  letter-spacing: 0.02em;
  color: var(--color-text);
}
.nav {
  display: flex;
  gap: var(--space-8);
  font-size: var(--text-sm);
  font-weight: 500;
}
.nav a { color: var(--color-text-muted); transition: color var(--transition-interactive); }
.nav a:hover { color: var(--color-primary); }
.nav__cta { display: none; }

@media (max-width: 800px) {
  .nav { display: none; }
  .nav__cta { display: inline-flex; }
}

/* ============================================
   Buttons
   ============================================ */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-2);
  font-family: var(--font-body);
  font-weight: 600;
  font-size: var(--text-sm);
  padding: var(--space-4) var(--space-8);
  border-radius: var(--radius-full);
  transition: transform var(--transition-interactive), box-shadow var(--transition-interactive), background var(--transition-interactive);
  white-space: nowrap;
}
.btn--primary {
  background: linear-gradient(135deg, var(--color-gold-hover), var(--color-gold));
  color: #1a1206;
  box-shadow: var(--shadow-sm);
}
.btn--primary:hover {
  background: linear-gradient(135deg, var(--color-gold), var(--color-gold-active));
  box-shadow: var(--shadow-md);
  transform: translateY(-1px);
}
.btn--ghost {
  background: transparent;
  color: var(--color-text);
  border: 1px solid var(--color-border);
}
.btn--ghost:hover { border-color: var(--color-primary); color: var(--color-primary); }
.btn--sm { padding: var(--space-2) var(--space-5); font-size: var(--text-xs); }

/* ============================================
   Shared type helpers
   ============================================ */
.eyebrow {
  font-size: var(--text-xs);
  font-weight: 600;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--color-primary);
  margin-bottom: var(--space-3);
}
.eyebrow.center { text-align: center; }
.section-title {
  font-size: var(--text-xl);
  font-weight: 600;
  margin-bottom: var(--space-6);
  color: var(--color-text);
}
.section-title.center { text-align: center; margin-inline: auto; max-width: 40ch; }

/* ============================================
   Hero
   ============================================ */
.hero {
  position: relative;
  padding-block: clamp(var(--space-20), 14vw, var(--space-32)) clamp(var(--space-16), 10vw, var(--space-24));
  overflow: hidden;
}
.hero__bg {
  position: absolute;
  inset: 0;
  background:
    radial-gradient(ellipse 60% 50% at 80% 0%, rgba(92, 184, 174, 0.16), transparent 60%),
    radial-gradient(ellipse 50% 40% at 10% 20%, rgba(207, 159, 78, 0.10), transparent 60%);
  z-index: 0;
}
.hero__inner {
  position: relative;
  z-index: 1;
  max-width: 760px;
}
.hero__title {
  font-size: var(--text-hero);
  font-weight: 600;
  letter-spacing: -0.01em;
  margin-bottom: var(--space-6);
}
.hero__title em {
  font-style: italic;
  color: var(--color-primary);
}
.hero__lead {
  font-size: var(--text-lg);
  color: var(--color-text-muted);
  max-width: 52ch;
  margin-bottom: var(--space-8);
}
.hero__actions {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-4);
  margin-bottom: var(--space-10);
}
.hero__proof {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-6);
  font-size: var(--text-xs);
  color: var(--color-text-faint);
}
.hero__proof-item {
  position: relative;
  padding-left: var(--space-4);
}
.hero__proof-item::before {
  content: '';
  position: absolute;
  left: 0;
  top: 50%;
  transform: translateY(-50%);
  width: 6px;
  height: 6px;
  border-radius: var(--radius-full);
  background: var(--color-primary);
}

/* ============================================
   Science section
   ============================================ */
.science {
  padding-block: clamp(var(--space-16), 10vw, var(--space-24));
  background: var(--color-surface);
  border-top: 1px solid var(--color-divider);
  border-bottom: 1px solid var(--color-divider);
}
.science__grid {
  display: grid;
  grid-template-columns: 280px 1fr;
  gap: var(--space-16);
  align-items: center;
}
.science__visual { display: flex; justify-content: center; }
.science__circle {
  width: 240px;
  height: 240px;
  border-radius: var(--radius-full);
  border: 2px solid var(--color-primary);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  background: radial-gradient(circle, rgba(92, 184, 174, 0.12), transparent 70%);
}
.science__stat {
  font-family: var(--font-display);
  font-size: var(--text-2xl);
  font-weight: 700;
  color: var(--color-gold-hover);
}
.science__stat-label {
  font-size: var(--text-xs);
  color: var(--color-text-muted);
  text-align: center;
  max-width: 14ch;
  margin-top: var(--space-2);
}
.science__text {
  color: var(--color-text-muted);
  margin-bottom: var(--space-4);
  max-width: 68ch;
}
.science__text em { color: var(--color-primary); font-style: normal; font-weight: 600; }
.science__source {
  font-size: var(--text-xs);
  color: var(--color-text-faint);
  margin-top: var(--space-4);
}
.science__source a { color: var(--color-primary); text-decoration: underline; text-decoration-color: rgba(92,184,174,0.4); }
.science__source a:hover { color: var(--color-primary-hover); }

@media (max-width: 760px) {
  .science__grid { grid-template-columns: 1fr; gap: var(--space-8); }
  .science__circle { width: 180px; height: 180px; }
}

/* ============================================
   Product sections
   ============================================ */
.product {
  padding-block: clamp(var(--space-16), 10vw, var(--space-24));
}
.product--alt { background: var(--color-surface); }
.product__grid {
  display: grid;
  grid-template-columns: 1.1fr 0.9fr;
  gap: var(--space-16);
  align-items: center;
}
.product__grid--reverse { direction: rtl; }
.product__grid--reverse > * { direction: ltr; }
.product__text {
  color: var(--color-text-muted);
  max-width: 60ch;
  margin-bottom: var(--space-6);
}
.product__features {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: var(--space-3);
  margin-bottom: var(--space-8);
}
.product__features li {
  display: flex;
  align-items: flex-start;
  gap: var(--space-3);
  font-size: var(--text-sm);
  color: var(--color-text);
}
.check {
  color: var(--color-primary);
  font-weight: 700;
  flex-shrink: 0;
}
.product__buy {
  display: flex;
  align-items: center;
  gap: var(--space-6);
  flex-wrap: wrap;
}
.price {
  font-family: var(--font-display);
  font-size: var(--text-xl);
  font-weight: 700;
  color: var(--color-gold-hover);
}
.product__visual {
  aspect-ratio: 4/5;
  border-radius: var(--radius-xl);
  display: flex;
  align-items: center;
  justify-content: center;
  position: relative;
  border: 1px solid var(--color-border);
  overflow: hidden;
}
.product__visual--reset7 {
  background: linear-gradient(160deg, var(--color-primary-highlight), var(--color-surface-2));
}
.product__visual--reset21 {
  background: linear-gradient(160deg, var(--color-gold-highlight), var(--color-surface-2));
}
.product__visual img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  object-position: center;
}

@media (max-width: 800px) {
  .product__grid, .product__grid--reverse { grid-template-columns: 1fr; direction: ltr; }
  .product__visual { aspect-ratio: 16/9; order: -1; }
}

/* ============================================
   How it works
   ============================================ */
.how { padding-block: clamp(var(--space-16), 10vw, var(--space-24)); }
.how__grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--space-8);
  margin-top: var(--space-10);
}
.how__card {
  background: var(--color-surface);
  border: 1px solid var(--color-divider);
  border-radius: var(--radius-lg);
  padding: var(--space-8);
}
.how__num {
  font-family: var(--font-display);
  font-size: var(--text-lg);
  color: var(--color-primary);
  font-weight: 700;
  display: block;
  margin-bottom: var(--space-4);
}
.how__title {
  font-size: var(--text-lg);
  font-weight: 600;
  margin-bottom: var(--space-2);
}
.how__text {
  font-size: var(--text-sm);
  color: var(--color-text-muted);
}

@media (max-width: 760px) {
  .how__grid { grid-template-columns: 1fr; }
}

/* ============================================
   FAQ
   ============================================ */
.faq {
  padding-block: clamp(var(--space-16), 10vw, var(--space-24));
  background: var(--color-surface);
  border-top: 1px solid var(--color-divider);
}
.faq__list {
  margin-top: var(--space-10);
  display: flex;
  flex-direction: column;
  gap: var(--space-3);
}
.faq__item {
  background: var(--color-surface-2);
  border: 1px solid var(--color-divider);
  border-radius: var(--radius-md);
  padding: var(--space-5) var(--space-6);
}
.faq__item summary {
  cursor: pointer;
  font-weight: 600;
  font-size: var(--text-base);
  list-style: none;
  display: flex;
  justify-content: space-between;
  align-items: center;
}
.faq__item summary::-webkit-details-marker { display: none; }
.faq__item summary::after {
  content: '+';
  font-size: var(--text-lg);
  color: var(--color-primary);
  margin-left: var(--space-4);
  transition: transform var(--transition-interactive);
}
.faq__item[open] summary::after { transform: rotate(45deg); }
.faq__item p {
  margin-top: var(--space-3);
  color: var(--color-text-muted);
  font-size: var(--text-sm);
}

/* ============================================
   Final CTA
   ============================================ */
.final-cta {
  padding-block: clamp(var(--space-20), 12vw, var(--space-32));
  text-align: center;
}
.final-cta__inner {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: var(--space-8);
}
.final-cta__title {
  font-size: var(--text-2xl);
  font-weight: 600;
  max-width: 20ch;
}

/* ============================================
   Footer
   ============================================ */
.footer {
  border-top: 1px solid var(--color-divider);
  padding-block: var(--space-10);
}
.footer__inner {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: var(--space-3);
  text-align: center;
}
.footer__brand {
  display: flex;
  align-items: center;
  gap: var(--space-2);
}
.footer__text, .footer__copy {
  font-size: var(--text-xs);
  color: var(--color-text-faint);
}
.footer__text a { color: var(--color-primary); text-decoration: underline; }