/* ==========================================================================
   AQNAS — Style System
   Colors: Obsidian #0F172A | Cinnabar #E34234 | Alabaster #F8FAFC | Slate #94A3B8
   Fonts: Space Grotesk (headings) | Inter (body)
   ========================================================================== */

/* --- Custom Properties --- */
:root {
  --obsidian: #0F172A;
  --cinnabar: #E34234;
  --alabaster: #F8FAFC;
  --slate: #94A3B8;
  --border: #E2E8F0;

  --font-heading: 'Space Grotesk', sans-serif;
  --font-body: 'Inter', sans-serif;

  --max-width: 1120px;
  --spacing-xs: 0.5rem;
  --spacing-sm: 1rem;
  --spacing-md: 2rem;
  --spacing-lg: 4rem;
  --spacing-xl: 6rem;
}

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

html {
  scroll-behavior: smooth;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  font-family: var(--font-body);
  font-size: 1rem;
  line-height: 1.6;
  color: var(--obsidian);
  background-color: var(--alabaster);
}

/* --- Typography --- */
h1, h2, h3 {
  font-family: var(--font-heading);
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  line-height: 1.2;
}

/* --- Nav --- */
.nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0.75rem var(--spacing-sm);
  background-color: rgba(15, 23, 42, 0.9);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  transform: translateY(-100%);
  opacity: 0;
  transition: transform 0.3s ease, opacity 0.3s ease;
}

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

.nav__brand {
  display: flex;
  align-items: center;
  text-decoration: none;
  opacity: 0.7;
  transition: opacity 0.2s;
  flex-shrink: 0;
}

.nav__brand:hover {
  opacity: 1;
}

.nav__links {
  display: flex;
  gap: var(--spacing-xs);
}

.nav__link {
  font-family: var(--font-heading);
  font-size: 0.625rem;
  font-weight: 700;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  text-decoration: none;
  color: var(--slate);
  padding: 0.25rem 0;
  border-bottom: 2px solid transparent;
  transition: color 0.2s, border-color 0.2s;
  white-space: nowrap;
}

.nav__link:hover {
  color: var(--alabaster);
}

.nav__link.is-active {
  color: var(--alabaster);
  border-bottom-color: var(--cinnabar);
}

/* --- Hero --- */
.hero {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  height: 100vh;
  height: 100dvh;
  overflow: hidden;
  background-color: var(--obsidian);
  color: var(--alabaster);
  text-align: center;
  padding: var(--spacing-md);
  position: relative;
}

.hero__logo {
  width: 80px;
  height: auto;
  margin-bottom: var(--spacing-md);
}

.hero__wordmark {
  font-family: var(--font-heading);
  font-size: clamp(2rem, 5vw, 3.5rem);
  font-weight: 700;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  margin-bottom: var(--spacing-sm);
}

.hero__tagline {
  font-family: var(--font-body);
  font-size: clamp(1rem, 2.5vw, 1.25rem);
  color: var(--slate);
  font-weight: 400;
  max-width: 600px;
}

.hero__accent {
  width: 48px;
  height: 3px;
  background-color: var(--cinnabar);
  border: none;
  margin-top: var(--spacing-md);
}

.hero__scroll-hint {
  position: absolute;
  bottom: var(--spacing-md);
  left: 50%;
  transform: translateX(-50%);
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.5rem;
  opacity: 0.4;
  transition: opacity 0.3s;
}

.hero__scroll-hint:hover {
  opacity: 0.7;
}

.hero__scroll-hint span {
  font-size: 0.75rem;
  letter-spacing: 0.15em;
  text-transform: uppercase;
  color: var(--slate);
}

.hero__scroll-hint svg {
  width: 20px;
  height: 20px;
  stroke: var(--slate);
  animation: bounce 2s infinite;
}

@keyframes bounce {
  0%, 20%, 50%, 80%, 100% { transform: translateY(0); }
  40% { transform: translateY(6px); }
  60% { transform: translateY(3px); }
}

/* --- Sections (Hunt / Forge / Strike) --- */
.section {
  min-height: 100vh;
  min-height: 100dvh;
  display: flex;
  flex-direction: column;
  align-items: center;
  padding: 3rem var(--spacing-md);
  max-width: var(--max-width);
  margin: 0 auto;
}

.section__header {
  text-align: center;
  margin-bottom: var(--spacing-lg);
}

.section__label {
  font-size: 0.75rem;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--cinnabar);
  font-family: var(--font-heading);
  font-weight: 700;
  margin-bottom: var(--spacing-xs);
}

.section__title {
  font-size: clamp(1.5rem, 3vw, 2rem);
  color: var(--obsidian);
}

.section__grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--spacing-md);
  flex: 1;
  align-content: center;
  width: 100%;
}

.section__empty {
  text-align: center;
  color: var(--slate);
  font-style: italic;
  font-size: 0.9375rem;
  padding: var(--spacing-lg) 0;
}

.problem-card {
  border: 1px solid var(--border);
  border-radius: 4px;
  padding: var(--spacing-md) var(--spacing-md);
  background: white;
  max-width: 700px;
  margin: 0 auto;
  opacity: 0;
  transform: translateY(20px);
  transition: opacity 0.5s ease, transform 0.5s ease, border-color 0.2s;
}

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

.problem-card:hover {
  border-color: var(--slate);
}

.problem-card__title {
  font-family: var(--font-heading);
  font-size: clamp(1.25rem, 2.5vw, 1.5rem);
  font-weight: 700;
  color: var(--obsidian);
  margin-bottom: 0.5rem;
  text-transform: none;
  letter-spacing: 0;
  line-height: 1.4;
}

.problem-card__tagline {
  font-size: 1.0625rem;
  color: var(--obsidian);
  line-height: 1.5;
  font-weight: 500;
}

.problem-card__divider {
  width: 32px;
  height: 2px;
  background-color: var(--cinnabar);
  border: none;
  margin: var(--spacing-sm) 0;
}

.problem-card__story {
  font-size: 0.9375rem;
  color: var(--slate);
  line-height: 1.7;
}

/* --- Footer --- */
.footer {
  background-color: var(--obsidian);
  color: var(--alabaster);
  padding: var(--spacing-lg) var(--spacing-md);
  text-align: center;
}

.footer__vision {
  font-family: var(--font-body);
  font-size: 0.9375rem;
  color: var(--slate);
  font-style: italic;
  max-width: 480px;
  margin: 0 auto var(--spacing-md);
  line-height: 1.6;
}

.footer__divider {
  width: 32px;
  height: 2px;
  background-color: var(--cinnabar);
  border: none;
  margin: 0 auto var(--spacing-md);
}

.footer__copy {
  font-size: 0.8125rem;
  color: var(--slate);
  opacity: 0.6;
}

/* --- Responsive --- */
@media (min-width: 640px) {
  .nav {
    padding: 0.75rem var(--spacing-md);
  }

  .nav__links {
    gap: var(--spacing-md);
  }

  .nav__link {
    font-size: 0.75rem;
    letter-spacing: 0.15em;
  }

  .section {
    padding: var(--spacing-xl) var(--spacing-md);
  }

  .problem-card {
    padding: var(--spacing-lg) var(--spacing-md);
  }
}

@media (min-width: 1024px) {
  .hero__logo {
    width: 100px;
  }
}