/* ============================================================
   Puzzli — Main Stylesheet
   Global styles for the portal (landing page + shared UI)
   ============================================================ */

/* ----------------------------------------------------------
   1. CSS Custom Properties
   ---------------------------------------------------------- */
:root {
  /* Colors */
  --color-bg:          #0f0f13;
  --color-surface:     #1a1a24;
  --color-surface-2:   #22223a;
  --color-primary:     #7c3aed;
  --color-primary-hover: #6d28d9;
  --color-accent:      #06b6d4;
  --color-text:        #f1f5f9;
  --color-text-muted:  #94a3b8;
  --color-border:      rgba(255, 255, 255, 0.08);

  /* Typography */
  --font-sans: 'Inter', system-ui, -apple-system, sans-serif;
  --font-size-sm:   0.875rem;
  --font-size-base: 1rem;
  --font-size-lg:   1.125rem;
  --font-size-xl:   1.25rem;
  --font-size-2xl:  1.5rem;
  --font-size-3xl:  1.875rem;
  --font-size-4xl:  2.25rem;

  /* Spacing */
  --space-1:  0.25rem;
  --space-2:  0.5rem;
  --space-3:  0.75rem;
  --space-4:  1rem;
  --space-6:  1.5rem;
  --space-8:  2rem;
  --space-12: 3rem;
  --space-16: 4rem;
  --space-24: 6rem;

  /* Layout */
  --max-width: 1200px;
  --radius-sm: 0.5rem;
  --radius-md: 0.75rem;
  --radius-lg: 1rem;
  --radius-xl: 1.5rem;

  /* Transitions */
  --transition-fast: 150ms ease;
  --transition-base: 250ms ease;
}

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

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

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

/* ----------------------------------------------------------
   3. Utility
   ---------------------------------------------------------- */
.container {
  width: 100%;
  max-width: var(--max-width);
  margin-inline: auto;
  padding-inline: var(--space-6);
}

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

/* ----------------------------------------------------------
   4. Navigation
   ---------------------------------------------------------- */
.nav {
  position: sticky;
  top: 0;
  z-index: 100;
  background-color: rgba(15, 15, 19, 0.85);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--color-border);
}

.nav__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 64px;
}

.nav__logo {
  font-size: var(--font-size-xl);
  font-weight: 800;
  letter-spacing: -0.03em;
  background: linear-gradient(135deg, var(--color-primary), var(--color-accent));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.nav__actions {
  display: flex;
  align-items: center;
  gap: var(--space-3);
}

/* ----------------------------------------------------------
   5. Buttons
   ---------------------------------------------------------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-2);
  padding: var(--space-2) var(--space-6);
  border-radius: var(--radius-md);
  font-size: var(--font-size-sm);
  font-weight: 600;
  transition: background-color var(--transition-fast),
              color var(--transition-fast),
              transform var(--transition-fast),
              box-shadow var(--transition-fast);
  white-space: nowrap;
  user-select: none;
}

.btn:focus-visible {
  outline: 2px solid var(--color-accent);
  outline-offset: 2px;
}

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

.btn--ghost:hover {
  color: var(--color-text);
  border-color: rgba(255, 255, 255, 0.2);
  background-color: var(--color-surface);
}

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

.btn--primary:hover {
  background-color: var(--color-primary-hover);
  transform: translateY(-1px);
  box-shadow: 0 4px 20px rgba(124, 58, 237, 0.4);
}

.btn--primary:active {
  transform: translateY(0);
}

/* ----------------------------------------------------------
   6. Language Switcher
   ---------------------------------------------------------- */
.lang-switcher {
  position: relative;
}

.lang-switcher__btn {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  padding: var(--space-2) var(--space-3);
  border-radius: var(--radius-md);
  font-size: var(--font-size-sm);
  font-weight: 600;
  color: var(--color-text-muted);
  border: 1px solid var(--color-border);
  background: none;
  cursor: pointer;
  transition: color var(--transition-fast), border-color var(--transition-fast), background-color var(--transition-fast);
  user-select: none;
}

.lang-switcher__btn:hover {
  color: var(--color-text);
  border-color: rgba(255, 255, 255, 0.2);
  background-color: var(--color-surface);
}

.lang-switcher__btn:focus-visible {
  outline: 2px solid var(--color-accent);
  outline-offset: 2px;
}

.lang-switcher__icon {
  font-size: 1rem;
  line-height: 1;
}

.lang-switcher__chevron {
  width: 14px;
  height: 14px;
  transition: transform var(--transition-fast);
  flex-shrink: 0;
}

.lang-switcher[aria-expanded="true"] .lang-switcher__chevron {
  transform: rotate(180deg);
}

.lang-switcher__dropdown {
  position: absolute;
  top: calc(100% + var(--space-2));
  right: 0;
  min-width: 140px;
  background-color: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: var(--space-1);
  box-shadow: 0 8px 24px rgba(0, 0, 0, 0.4);
  opacity: 0;
  visibility: hidden;
  transform: translateY(-6px);
  transition: opacity var(--transition-fast),
              transform var(--transition-fast),
              visibility var(--transition-fast);
  z-index: 200;
}

.lang-switcher[aria-expanded="true"] .lang-switcher__dropdown {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}

.lang-switcher__option {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  width: 100%;
  padding: var(--space-2) var(--space-3);
  border-radius: var(--radius-sm);
  font-size: var(--font-size-sm);
  font-weight: 500;
  color: var(--color-text-muted);
  transition: background-color var(--transition-fast), color var(--transition-fast);
  text-decoration: none;
}

.lang-switcher__option:hover {
  background-color: var(--color-surface-2);
  color: var(--color-text);
}

.lang-switcher__option[aria-current="true"] {
  color: var(--color-accent);
  font-weight: 700;
}

.lang-switcher__option-flag {
  font-size: 1.1rem;
  line-height: 1;
}

/* ----------------------------------------------------------
   7. Hero
   ---------------------------------------------------------- */
.hero {
  padding-block: var(--space-24) var(--space-8);
  text-align: center;
}

.hero__eyebrow {
  display: inline-block;
  font-size: var(--font-size-sm);
  font-weight: 600;
  color: var(--color-accent);
  text-transform: uppercase;
  letter-spacing: 0.1em;
  margin-bottom: var(--space-4);
}

.hero__title {
  font-size: clamp(var(--font-size-3xl), 6vw, 4rem);
  font-weight: 800;
  line-height: 1.1;
  letter-spacing: -0.03em;
  margin-bottom: var(--space-6);
}

.hero__title span {
  background: linear-gradient(135deg, var(--color-primary), var(--color-accent));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero__description {
  max-width: 560px;
  margin-inline: auto;
  font-size: var(--font-size-lg);
  color: var(--color-text-muted);
  margin-bottom: var(--space-8);
}

/* ----------------------------------------------------------
   7. Games Grid
   ---------------------------------------------------------- */
.games {
  padding-block: var(--space-8) var(--space-24);
}

.games__heading {
  font-size: var(--font-size-2xl);
  font-weight: 700;
  margin-bottom: var(--space-8);
  letter-spacing: -0.02em;
}

.games__grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
  gap: var(--space-6);
}

/* ----------------------------------------------------------
   8. Game Card
   ---------------------------------------------------------- */
.card {
  background-color: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-xl);
  padding: var(--space-6);
  display: flex;
  flex-direction: column;
  align-items: center;
  text-align: center;
  gap: var(--space-4);
  transition: transform var(--transition-base),
              border-color var(--transition-base),
              box-shadow var(--transition-base);
}

.card:hover {
  transform: translateY(-4px);
  border-color: rgba(124, 58, 237, 0.5);
  box-shadow: 0 8px 32px rgba(124, 58, 237, 0.15);
}

.card__icon {
  width: 72px;
  height: 72px;
  border-radius: var(--radius-lg);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 2rem;
  flex-shrink: 0;
}

.card__title {
  font-size: var(--font-size-xl);
  font-weight: 700;
  letter-spacing: -0.01em;
}

.card__description {
  font-size: var(--font-size-sm);
  color: var(--color-text-muted);
  line-height: 1.5;
  flex: 1;
}

.card__btn {
  width: 100%;
  padding-block: var(--space-3);
  border-radius: var(--radius-md);
  font-size: var(--font-size-sm);
  font-weight: 700;
  letter-spacing: 0.01em;
  background-color: var(--color-surface-2);
  color: var(--color-text);
  border: 1px solid var(--color-border);
  transition: background-color var(--transition-fast),
              border-color var(--transition-fast),
              transform var(--transition-fast);
}

.card__btn:hover {
  background-color: var(--color-primary);
  border-color: var(--color-primary);
  transform: translateY(-1px);
}

.card__btn:focus-visible {
  outline: 2px solid var(--color-accent);
  outline-offset: 2px;
}

/* ----------------------------------------------------------
   9. Footer
   ---------------------------------------------------------- */
.footer {
  border-top: 1px solid var(--color-border);
  padding-block: var(--space-12) var(--space-8);
  margin-top: var(--space-8);
}

.footer__main {
  display: grid;
  grid-template-columns: 1fr auto auto;
  gap: var(--space-12);
  padding-bottom: var(--space-8);
  border-bottom: 1px solid var(--color-border);
  margin-bottom: var(--space-6);
}

.footer__brand {
  max-width: 280px;
}

.footer__logo {
  display: inline-block;
  font-size: var(--font-size-xl);
  font-weight: 800;
  letter-spacing: -0.03em;
  background: linear-gradient(135deg, var(--color-primary), var(--color-accent));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  margin-bottom: var(--space-3);
}

.footer__tagline {
  font-size: var(--font-size-sm);
  color: var(--color-text-muted);
  line-height: 1.6;
}

.footer__col-title {
  font-size: var(--font-size-sm);
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--color-text-muted);
  margin-bottom: var(--space-4);
}

.footer__games-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(120px, 1fr));
  gap: var(--space-2) var(--space-8);
}

.footer__game-link {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  font-size: var(--font-size-sm);
  color: var(--color-text-muted);
  transition: color var(--transition-fast);
  white-space: nowrap;
}

.footer__game-link:hover {
  color: var(--color-text);
}

.footer__game-icon {
  font-size: 1rem;
  flex-shrink: 0;
}

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

.footer__link {
  font-size: var(--font-size-sm);
  color: var(--color-text-muted);
  transition: color var(--transition-fast);
  white-space: nowrap;
}

.footer__link:hover {
  color: var(--color-text);
}

.footer__bottom {
  display: flex;
  align-items: center;
  justify-content: space-between;
}

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

/* ----------------------------------------------------------
   10. Responsive
   ---------------------------------------------------------- */
@media (max-width: 900px) {
  .footer__main {
    grid-template-columns: 1fr 1fr;
    grid-template-rows: auto auto;
  }

  .footer__brand {
    grid-column: 1 / -1;
    max-width: 100%;
  }
}

@media (max-width: 640px) {
  .container {
    padding-inline: var(--space-4);
  }

  .hero {
    padding-block: var(--space-16) var(--space-12);
  }

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

  .games__grid {
    grid-template-columns: 1fr;
  }

  .footer__main {
    grid-template-columns: 1fr;
  }

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

  .footer__bottom {
    flex-direction: column;
    gap: var(--space-2);
    text-align: center;
  }
}