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

:root {
  --color-bg: #0a0a0a;
  --color-surface: #141414;
  --color-text: #f5f5f5;
  --color-text-secondary: #a1a1a1;
  --color-accent: #3b82f6;
  --color-accent-hover: #60a5fa;
  --color-border: #262626;
  --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
}

html {
  scroll-behavior: smooth;
  scroll-snap-type: y mandatory;
  overflow-y: scroll;
}

body {
  font-family: var(--font-sans);
  color: var(--color-text);
  background: var(--color-bg);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

a {
  color: var(--color-accent);
  text-decoration: none;
  transition: color 0.2s;
}

a:hover {
  color: var(--color-accent-hover);
}

/* Nav */

.nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 1rem 2rem;
  background: rgba(10, 10, 10, 0.8);
  backdrop-filter: blur(12px);
}

.nav-logo {
  font-weight: 700;
  font-size: 1.125rem;
  color: var(--color-text);
  letter-spacing: -0.02em;
}

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

.nav-links {
  list-style: none;
  display: flex;
  gap: 1.5rem;
}

.nav-links a {
  font-size: 0.8125rem;
  font-weight: 500;
  color: var(--color-text-secondary);
  transition: color 0.2s;
}

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

/* Dots */

.dots {
  position: fixed;
  right: 2rem;
  top: 50%;
  transform: translateY(-50%);
  z-index: 100;
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
}

.dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--color-border);
  transition: background 0.3s, transform 0.3s;
}

.dot:hover {
  background: var(--color-text-secondary);
  transform: scale(1.3);
}

.dot.active {
  background: var(--color-accent);
  transform: scale(1.4);
}

/* Screens */

.screens {
  scroll-snap-type: y mandatory;
}

.screen {
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  scroll-snap-align: start;
  padding: 6rem 2rem 2rem;
}

.screen-inner {
  max-width: 600px;
  width: 100%;
}

.screen-date {
  display: inline-block;
  font-size: 0.75rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--color-accent);
  margin-bottom: 0.75rem;
}

.screen h2 {
  font-size: 2.5rem;
  font-weight: 700;
  letter-spacing: -0.03em;
  line-height: 1.15;
  margin-bottom: 0.5rem;
}

.screen-org {
  font-size: 1.125rem;
  color: var(--color-text-secondary);
  margin-bottom: 1rem;
}

.screen-desc {
  font-size: 1.0625rem;
  color: var(--color-text-secondary);
  line-height: 1.7;
  margin-bottom: 1.5rem;
}

.screen-link {
  display: inline-flex;
  align-items: center;
  gap: 0.375rem;
  font-size: 0.9375rem;
  font-weight: 500;
}

.screen-link::after {
  content: '→';
  transition: transform 0.2s;
}

.screen-link:hover::after {
  transform: translateX(3px);
}

/* Hero */

.hero-img {
  width: 140px;
  height: 140px;
  border-radius: 50%;
  object-fit: cover;
  margin-bottom: 2rem;
  border: 3px solid var(--color-border);
}

.screen-hero h1 {
  font-size: 3rem;
  font-weight: 700;
  letter-spacing: -0.04em;
  line-height: 1.1;
  margin-bottom: 0.75rem;
}

.hero-tagline {
  font-size: 1.125rem;
  color: var(--color-text-secondary);
  margin-bottom: 3rem;
}

.scroll-hint {
  font-size: 0.8125rem;
  color: var(--color-text-secondary);
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  animation: pulse 2s ease-in-out infinite;
}

.scroll-hint::after {
  content: '↓';
}

@keyframes pulse {
  0%, 100% { opacity: 0.5; }
  50% { opacity: 1; }
}

/* Software */

.screen-software {
  background: var(--color-bg);
}

/* Product */

.screen-product {
  background: var(--color-surface);
}

/* Research */

.screen-research {
  background: var(--color-bg);
}

/* Education */

.screen-education {
  background: var(--color-surface);
}

.edu-cards {
  display: flex;
  flex-direction: column;
  gap: 1.25rem;
}

.edu-card {
  padding: 1.75rem;
  background: var(--color-bg);
  border: 1px solid var(--color-border);
  border-radius: 10px;
}

.edu-year {
  font-size: 0.75rem;
  font-weight: 600;
  color: var(--color-accent);
  text-transform: uppercase;
  letter-spacing: 0.08em;
}

.edu-card h3 {
  font-size: 1.0625rem;
  font-weight: 600;
  margin-top: 0.375rem;
}

.edu-card p {
  font-size: 0.9375rem;
  color: var(--color-text-secondary);
  margin-top: 0.25rem;
}

/* Support */

.screen-support {
  background: var(--color-surface);
}

.support-tiers {
  display: flex;
  gap: 1rem;
  margin-bottom: 2rem;
}

.support-tier {
  flex: 1;
  padding: 1.5rem;
  background: var(--color-bg);
  border: 1px solid var(--color-border);
  border-radius: 10px;
  text-align: center;
  transition: border-color 0.2s;
}

.support-tier:hover {
  border-color: var(--color-accent);
}

.support-amount {
  font-size: 1.5rem;
  font-weight: 700;
  letter-spacing: -0.02em;
}

.bank-details {
  display: flex;
  gap: 0.75rem;
  flex-wrap: wrap;
}

.bank-label {
  font-size: 0.75rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--color-text-secondary);
  background: var(--color-bg);
  padding: 0.375rem 0.75rem;
  border-radius: 4px;
}

.bank-value {
  font-size: 0.9375rem;
  font-weight: 500;
  display: inline-flex;
  align-items: center;
}

/* Contact */

.screen-contact {
  background: var(--color-bg);
}

.screen-contact h2 {
  margin-bottom: 2rem;
}

.contact-list {
  display: flex;
  flex-direction: column;
  gap: 0;
}

.contact-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 1.25rem 0;
  border-bottom: 1px solid var(--color-border);
  transition: padding-left 0.2s;
}

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

.contact-row:hover {
  padding-left: 0.5rem;
}

.contact-label {
  font-size: 0.8125rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--color-text-secondary);
}

.contact-value {
  font-size: 0.9375rem;
  font-weight: 500;
  color: var(--color-text);
}

/* Responsive */

@media (max-width: 640px) {
  .nav-links {
    display: none;
  }

  .dots {
    right: 1rem;
  }

  .screen {
    padding: 5rem 1.5rem 2rem;
  }

  .screen-hero h1 {
    font-size: 2rem;
  }

  .screen h2 {
    font-size: 1.75rem;
  }
}