/* ==========================================================================
   Custom Properties — Vis1on Brand
   ========================================================================== */

:root {
  /* Brand Colors */
  --color-teal: #009CA6;
  --color-teal-dark: #007F87;
  --color-teal-light: #00BCC8;
  --color-teal-glow: rgba(0, 156, 166, 0.15);
  --color-teal-subtle: rgba(0, 156, 166, 0.08);

  /* Neutrals */
  --color-dark: #0a0f1a;
  --color-dark-accent: #111827;
  --color-dark-surface: #151c2c;
  --color-white: #ffffff;
  --color-light: #f7f9fc;
  --color-gray: #6b7280;
  --color-gray-light: #e5e7eb;
  --color-gray-dark: #374151;
  --color-text: #d1d5db;

  /* Typography */
  --font-stack: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto,
    "Helvetica Neue", Arial, "Noto Sans", sans-serif;
  --font-size-base: 1rem;
  --font-size-sm: 0.875rem;
  --font-size-lg: 1.125rem;
  --font-size-xl: 1.35rem;
  --font-size-2xl: 2rem;
  --font-size-3xl: 2.75rem;
  --font-size-4xl: 3.5rem;
  --line-height-body: 1.75;
  --line-height-heading: 1.12;

  /* Spacing */
  --space-xs: 0.5rem;
  --space-sm: 1rem;
  --space-md: 1.5rem;
  --space-lg: 3rem;
  --space-xl: 5rem;
  --space-2xl: 8rem;

  /* Layout */
  --container-max: 1120px;
  --nav-height: 64px;

  /* Effects */
  --radius: 8px;
  --radius-lg: 16px;
  --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.06);
  --shadow-md: 0 8px 30px rgba(0, 0, 0, 0.12);
  --shadow-glow: 0 0 40px rgba(0, 156, 166, 0.15);
  --transition: 0.3s ease;
  --transition-slow: 0.6s ease;
}

/* ==========================================================================
   Reset & Base
   ========================================================================== */

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

html {
  scroll-behavior: smooth;
  scroll-padding-top: var(--nav-height);
}

body {
  font-family: var(--font-stack);
  font-size: var(--font-size-base);
  line-height: var(--line-height-body);
  color: var(--color-dark);
  background: var(--color-white);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

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

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

ul {
  list-style: none;
}

/* ==========================================================================
   Layout
   ========================================================================== */

.container {
  width: 100%;
  max-width: var(--container-max);
  margin: 0 auto;
  padding: 0 var(--space-md);
}

.section {
  padding: var(--space-2xl) 0;
}

.section--alt {
  background: var(--color-light);
}

.section__label {
  font-size: var(--font-size-sm);
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.12em;
  color: var(--color-teal);
  margin-bottom: var(--space-xs);
}

.section__title {
  font-size: var(--font-size-3xl);
  font-weight: 800;
  margin-bottom: var(--space-md);
  letter-spacing: -0.03em;
  line-height: var(--line-height-heading);
  color: var(--color-dark);
}

.section__intro {
  font-size: var(--font-size-lg);
  color: var(--color-gray);
  max-width: 640px;
  margin-bottom: var(--space-xl);
  line-height: var(--line-height-body);
}

/* ==========================================================================
   Button
   ========================================================================== */

.btn {
  display: inline-block;
  padding: 0.9rem 2.2rem;
  font-size: var(--font-size-base);
  font-weight: 600;
  border-radius: var(--radius);
  border: none;
  cursor: pointer;
  transition: background var(--transition), transform var(--transition), box-shadow var(--transition);
  letter-spacing: 0.01em;
}

.btn--primary {
  background: var(--color-teal);
  color: var(--color-white);
}

.btn--primary:hover {
  background: var(--color-teal-dark);
  transform: translateY(-2px);
  box-shadow: 0 6px 20px rgba(0, 156, 166, 0.3);
}

.btn--white {
  background: var(--color-white);
  color: var(--color-dark);
}

.btn--white:hover {
  transform: translateY(-2px);
  box-shadow: 0 6px 20px rgba(255, 255, 255, 0.2);
}

/* ==========================================================================
   Navigation
   ========================================================================== */

.site-header {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: var(--nav-height);
  z-index: 1000;
  background: rgba(10, 15, 26, 0.92);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  transition: box-shadow var(--transition);
}

.site-header--scrolled {
  box-shadow: 0 1px 0 rgba(0, 156, 166, 0.15);
}

.nav {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 100%;
}

.nav__logo {
  display: flex;
  align-items: center;
  opacity: 0;
  transform: translateY(-6px);
  pointer-events: none;
  transition: opacity 0.35s ease, transform 0.35s ease;
}

.site-header--scrolled .nav__logo {
  opacity: 1;
  transform: translateY(0);
  pointer-events: auto;
}

.nav__logo-svg {
  height: 36px;
  width: auto;
}

.nav__list {
  display: flex;
  gap: var(--space-lg);
}

.nav__link {
  color: rgba(255, 255, 255, 0.65);
  font-size: var(--font-size-sm);
  font-weight: 500;
  letter-spacing: 0.03em;
  transition: color var(--transition);
}

.nav__link:hover,
.nav__link--active {
  color: var(--color-white);
}

/* Hamburger */
.nav__toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 4px;
  z-index: 1001;
}

.nav__toggle-bar {
  display: block;
  width: 24px;
  height: 2px;
  background: var(--color-white);
  border-radius: 2px;
  transition: transform var(--transition), opacity var(--transition);
}

.nav__toggle.active .nav__toggle-bar:nth-child(1) {
  transform: translateY(7px) rotate(45deg);
}

.nav__toggle.active .nav__toggle-bar:nth-child(2) {
  opacity: 0;
}

.nav__toggle.active .nav__toggle-bar:nth-child(3) {
  transform: translateY(-7px) rotate(-45deg);
}

/* ==========================================================================
   Hero
   ========================================================================== */

.hero {
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--color-dark);
  color: var(--color-white);
  padding-top: var(--nav-height);
  position: relative;
  overflow: hidden;
  text-align: center;
}

.hero__canvas {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  opacity: 0.55;
  pointer-events: none;
}

.hero__inner {
  position: relative;
  z-index: 1;
  padding: var(--space-xl) 0;
}

.hero__logo-wrap {
  margin-bottom: var(--space-lg);
}

.hero__logo {
  width: 520px;
  max-width: 85vw;
  height: auto;
  margin: 0 auto;
  display: block;
}

.hero__subtitle {
  font-size: var(--font-size-xl);
  color: rgba(255, 255, 255, 0.7);
  max-width: 540px;
  margin: 0 auto var(--space-lg);
  line-height: var(--line-height-body);
}

/* ==========================================================================
   Science Section
   ========================================================================== */

.science__layout {
  display: grid;
  grid-template-columns: 1.2fr 0.8fr;
  gap: var(--space-xl);
  align-items: center;
}

.science__text p {
  color: var(--color-gray);
  font-size: var(--font-size-lg);
  margin-bottom: var(--space-md);
}

.science__text p:last-child {
  margin-bottom: 0;
}

.science__visual {
  display: flex;
  justify-content: center;
  align-items: center;
}

.science-image {
  width: 100%;
  max-width: 506px;
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: var(--shadow-md), 0 0 60px rgba(0, 156, 166, 0.12);
  border: 1px solid rgba(0, 156, 166, 0.15);
}

.science-image img {
  width: 100%;
  height: auto;
  display: block;
}

/* ==========================================================================
   Stats Band
   ========================================================================== */

.stats-band {
  background: var(--color-dark);
  padding: var(--space-xl) 0;
  position: relative;
  overflow: hidden;
}

.stats-band::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 1px;
  background: linear-gradient(90deg, transparent, var(--color-teal), transparent);
}

.stats-band::after {
  content: "";
  position: absolute;
  bottom: 0;
  left: 0;
  right: 0;
  height: 1px;
  background: linear-gradient(90deg, transparent, var(--color-teal), transparent);
}

.stats__grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: var(--space-lg);
  text-align: center;
}

.stat {
  opacity: 0;
  transform: translateY(20px);
  transition: opacity var(--transition-slow), transform var(--transition-slow);
}

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

.stat__number {
  font-size: 3.5rem;
  font-weight: 800;
  color: var(--color-teal);
  line-height: 1;
  letter-spacing: -0.03em;
}

.stat__suffix {
  font-size: 2rem;
  font-weight: 700;
  color: var(--color-teal);
}

.stat__label {
  display: block;
  margin-top: var(--space-xs);
  font-size: var(--font-size-sm);
  color: rgba(255, 255, 255, 0.5);
  line-height: 1.4;
}

/* ==========================================================================
   Pillars (Why It Matters)
   ========================================================================== */

.pillars__grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: var(--space-md);
}

.pillar {
  background: var(--color-white);
  border-radius: var(--radius-lg);
  padding: var(--space-lg);
  box-shadow: var(--shadow-sm);
  border: 1px solid var(--color-gray-light);
  transition: transform var(--transition), box-shadow var(--transition);
  opacity: 0;
  transform: translateY(24px);
}

.pillar.is-visible {
  opacity: 1;
  transform: translateY(0);
  transition: opacity var(--transition-slow), transform var(--transition-slow);
}

.pillar:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-md);
}

.pillar__icon {
  width: 48px;
  height: 48px;
  color: var(--color-teal);
  margin-bottom: var(--space-md);
}

.pillar__icon svg {
  width: 100%;
  height: 100%;
}

.pillar__title {
  font-size: var(--font-size-xl);
  font-weight: 700;
  margin-bottom: var(--space-xs);
  color: var(--color-dark);
  letter-spacing: -0.01em;
}

.pillar__text {
  color: var(--color-gray);
  font-size: var(--font-size-base);
  line-height: var(--line-height-body);
}

/* ==========================================================================
   Training Section
   ========================================================================== */

.training__layout {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--space-xl);
  align-items: start;
}

.training__text p {
  color: var(--color-gray);
  font-size: var(--font-size-lg);
  margin-bottom: var(--space-md);
}

.training__text p:last-child {
  margin-bottom: 0;
}

.training__steps {
  display: flex;
  flex-direction: column;
  gap: var(--space-md);
}

.step {
  display: flex;
  gap: var(--space-md);
  align-items: flex-start;
  padding: var(--space-md);
  border-radius: var(--radius-lg);
  background: var(--color-light);
  border: 1px solid var(--color-gray-light);
  opacity: 0;
  transform: translateX(24px);
  transition: opacity var(--transition-slow), transform var(--transition-slow), box-shadow var(--transition);
}

.step.is-visible {
  opacity: 1;
  transform: translateX(0);
}

.step:hover {
  box-shadow: var(--shadow-md);
}

.step__number {
  font-size: 2rem;
  font-weight: 800;
  color: var(--color-teal);
  line-height: 1;
  min-width: 48px;
  opacity: 0.7;
}

.step__title {
  font-size: var(--font-size-lg);
  font-weight: 700;
  color: var(--color-dark);
  margin-bottom: 4px;
}

.step__text {
  font-size: var(--font-size-sm);
  color: var(--color-gray);
  line-height: 1.6;
}

/* ==========================================================================
   CTA Band
   ========================================================================== */

.cta-band {
  background: linear-gradient(135deg, var(--color-dark) 0%, var(--color-dark-accent) 50%, #0a2025 100%);
  padding: var(--space-2xl) 0;
  text-align: center;
  position: relative;
  overflow: hidden;
}

.cta-band::before {
  content: "";
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  width: 600px;
  height: 600px;
  background: radial-gradient(circle, var(--color-teal-glow) 0%, transparent 70%);
  pointer-events: none;
}

.cta__inner {
  position: relative;
  z-index: 1;
}

.cta__title {
  font-size: var(--font-size-3xl);
  font-weight: 800;
  color: var(--color-white);
  letter-spacing: -0.03em;
  line-height: var(--line-height-heading);
  margin-bottom: var(--space-md);
}

.cta__text {
  font-size: var(--font-size-lg);
  color: rgba(255, 255, 255, 0.6);
  max-width: 520px;
  margin: 0 auto var(--space-lg);
}

/* ==========================================================================
   Contact
   ========================================================================== */

.contact {
  text-align: left;
}

.contact__layout {
  display: grid;
  grid-template-columns: auto 1fr;
  gap: var(--space-xl);
  align-items: center;
}

.contact__photo-wrap {
  width: 320px;
  flex-shrink: 0;
}

.contact__photo {
  width: 100%;
  height: auto;
  display: block;
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-md);
  border: 1px solid var(--color-gray-light);
}

.contact__info {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
}

.contact__name {
  font-size: var(--font-size-2xl);
  font-weight: 800;
  color: var(--color-dark);
  letter-spacing: -0.02em;
  margin-bottom: 2px;
}

.contact__role {
  font-size: var(--font-size-lg);
  font-weight: 600;
  color: var(--color-teal);
  margin-bottom: var(--space-md);
}

.contact__bio {
  color: var(--color-gray);
  font-size: var(--font-size-base);
  line-height: var(--line-height-body);
  margin-bottom: var(--space-sm);
}

.contact__cta-text {
  color: var(--color-gray);
  font-size: var(--font-size-base);
  line-height: var(--line-height-body);
  margin-bottom: var(--space-lg);
}

.contact__social-link:hover {
  background: var(--color-teal);
  color: var(--color-white);
  transform: translateY(-2px);
}

/* ==========================================================================
   Footer
   ========================================================================== */

.footer {
  background: var(--color-dark);
  color: rgba(255, 255, 255, 0.4);
  padding: var(--space-lg) 0;
  border-top: 1px solid rgba(255, 255, 255, 0.06);
}

.footer__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: var(--space-sm);
}

.footer__brand {
  display: flex;
  align-items: center;
}

.footer__logo {
  height: 28px;
  width: auto;
  opacity: 0.5;
  transition: opacity var(--transition);
}

.footer__logo:hover {
  opacity: 0.8;
}

.footer__copy {
  font-size: var(--font-size-sm);
}

.footer__nav {
  display: flex;
  gap: var(--space-md);
}

.footer__nav a {
  font-size: var(--font-size-sm);
  color: rgba(255, 255, 255, 0.4);
  transition: color var(--transition);
}

.footer__nav a:hover {
  color: var(--color-teal);
}

/* ==========================================================================
   Scroll Animations
   ========================================================================== */

[data-animate] {
  opacity: 0;
  transform: translateY(24px);
}

[data-animate].is-visible {
  opacity: 1;
  transform: translateY(0);
  transition: opacity 0.6s ease, transform 0.6s ease;
}

/* Stagger children */
.pillars__grid [data-animate]:nth-child(2) { transition-delay: 0.1s; }
.pillars__grid [data-animate]:nth-child(3) { transition-delay: 0.2s; }
.pillars__grid [data-animate]:nth-child(4) { transition-delay: 0.3s; }

.training__steps [data-animate]:nth-child(2) { transition-delay: 0.12s; }
.training__steps [data-animate]:nth-child(3) { transition-delay: 0.24s; }
.training__steps [data-animate]:nth-child(4) { transition-delay: 0.36s; }

.stats__grid .stat:nth-child(2) { transition-delay: 0.1s; }
.stats__grid .stat:nth-child(3) { transition-delay: 0.2s; }
.stats__grid .stat:nth-child(4) { transition-delay: 0.3s; }

/* ==========================================================================
   Responsive
   ========================================================================== */

@media (max-width: 768px) {
  :root {
    --font-size-4xl: 2.5rem;
    --font-size-3xl: 2rem;
    --font-size-2xl: 1.5rem;
  }

  .section {
    padding: var(--space-xl) 0;
  }

  /* Mobile nav */
  .nav__toggle {
    display: flex;
  }

  .nav__list {
    position: fixed;
    top: 0;
    right: 0;
    width: 280px;
    height: 100vh;
    background: var(--color-dark-accent);
    flex-direction: column;
    padding: calc(var(--nav-height) + var(--space-lg)) var(--space-lg) var(--space-lg);
    gap: var(--space-md);
    transform: translateX(100%);
    transition: transform var(--transition);
    box-shadow: -4px 0 30px rgba(0, 0, 0, 0.4);
  }

  .nav__list.open {
    transform: translateX(0);
  }

  .nav__link {
    font-size: var(--font-size-base);
  }

  /* Science layout stack */
  .science__layout {
    grid-template-columns: 1fr;
    gap: var(--space-lg);
  }

  .brain-diagram {
    width: 220px;
    height: 220px;
  }

  /* Pillars → stack */
  .pillars__grid {
    grid-template-columns: 1fr;
  }

  /* Training → stack */
  .training__layout {
    grid-template-columns: 1fr;
    gap: var(--space-lg);
  }

  /* Stats → 2x2 */
  .stats__grid {
    grid-template-columns: repeat(2, 1fr);
    gap: var(--space-md);
  }

  .stat__number {
    font-size: 2.5rem;
  }

  /* Contact → stack */
  .contact__layout {
    grid-template-columns: 1fr;
    gap: var(--space-lg);
    text-align: center;
  }

  .contact__photo-wrap {
    width: 240px;
    margin: 0 auto;
  }

  .contact__info {
    align-items: center;
  }

  .contact__bio,
  .contact__cta-text {
    text-align: center;
  }

  /* Footer stack */
  .footer__inner {
    flex-direction: column;
    text-align: center;
    gap: var(--space-sm);
  }

  .footer__nav {
    flex-wrap: wrap;
    justify-content: center;
  }

  .hero__inner {
    padding: var(--space-lg) 0;
  }

  .cta-band {
    padding: var(--space-xl) 0;
  }
}

@media (min-width: 769px) and (max-width: 1024px) {
  .pillars__grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .stats__grid {
    grid-template-columns: repeat(2, 1fr);
  }
}