/**
 * KIOSK Gift Box Builder - Main Styles
 * 
 * Design System:
 * - Colors: Charcoal background, off-white text, acid-green accents
 * - Typography: Modern, clean, accessible
 * - Layout: Mobile-first, responsive grid
 * - Accessibility: AA contrast, visible focus states, keyboard navigation
 */

/* ================================
   CSS Custom Properties (Variables)
   ================================ */
:root {
  /* Colors - Primary Palette */
  --color-charcoal: #1a1a1a;
  --color-charcoal-light: #2a2a2a;
  --color-charcoal-dark: #0f0f0f;
  
  --color-off-white: #f5f5f5;
  --color-off-white-dark: #e0e0e0;
  
  --color-acid-green: #d4ff00;
  --color-acid-green-dark: #b8e000;
  --color-acid-green-light: #e4ff66;
  
  /* Colors - Semantic */
  --color-bg: var(--color-charcoal);
  --color-text: var(--color-off-white);
  --color-text-muted: #9a9a9a;
  --color-primary: var(--color-acid-green);
  --color-primary-hover: var(--color-acid-green-dark);
  
  --color-error: #ff4444;
  --color-success: #44ff44;
  --color-warning: #ffaa00;
  --color-info: #44aaff;
  
  /* Typography */
  --font-sans: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
  --font-mono: 'SF Mono', Monaco, 'Cascadia Code', 'Courier New', monospace;
  
  --font-size-xs: 0.75rem;    /* 12px */
  --font-size-sm: 0.875rem;   /* 14px */
  --font-size-base: 1rem;     /* 16px */
  --font-size-lg: 1.125rem;   /* 18px */
  --font-size-xl: 1.25rem;    /* 20px */
  --font-size-2xl: 1.5rem;    /* 24px */
  --font-size-3xl: 1.875rem;  /* 30px */
  --font-size-4xl: 2.25rem;   /* 36px */
  --font-size-5xl: 3rem;      /* 48px */
  
  --font-weight-normal: 400;
  --font-weight-medium: 500;
  --font-weight-semibold: 600;
  --font-weight-bold: 700;
  
  --line-height-tight: 1.25;
  --line-height-normal: 1.5;
  --line-height-relaxed: 1.75;
  
  /* Spacing */
  --space-xs: 0.25rem;   /* 4px */
  --space-sm: 0.5rem;    /* 8px */
  --space-md: 1rem;      /* 16px */
  --space-lg: 1.5rem;    /* 24px */
  --space-xl: 2rem;      /* 32px */
  --space-2xl: 3rem;     /* 48px */
  --space-3xl: 4rem;     /* 64px */
  --space-4xl: 6rem;     /* 96px */
  
  /* Border Radius */
  --radius-sm: 4px;
  --radius-md: 8px;
  --radius-lg: 12px;
  --radius-xl: 16px;
  --radius-full: 9999px;
  
  /* Shadows */
  --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.3);
  --shadow-md: 0 4px 6px rgba(0, 0, 0, 0.4);
  --shadow-lg: 0 10px 15px rgba(0, 0, 0, 0.5);
  --shadow-xl: 0 20px 25px rgba(0, 0, 0, 0.6);
  
  /* Transitions */
  --transition-fast: 150ms ease;
  --transition-base: 250ms ease;
  --transition-slow: 350ms ease;
  
  /* Z-index */
  --z-base: 1;
  --z-dropdown: 100;
  --z-sticky: 200;
  --z-fixed: 300;
  --z-modal-backdrop: 400;
  --z-modal: 500;
  --z-popover: 600;
  --z-tooltip: 700;
  
  /* Layout */
  --container-max-width: 1280px;
  --container-padding: var(--space-md);
  --nav-height: 70px;
}

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

html {
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  text-rendering: optimizeLegibility;
}

body {
  font-family: var(--font-sans);
  font-size: var(--font-size-base);
  font-weight: var(--font-weight-normal);
  line-height: var(--line-height-normal);
  color: var(--color-text);
  background-color: var(--color-bg);
  overflow-x: hidden;
}

/* Smooth scrolling (will be enhanced by Lenis) */
html.lenis {
  height: auto;
}

.lenis.lenis-smooth {
  scroll-behavior: auto;
}

.lenis.lenis-smooth [data-lenis-prevent] {
  overscroll-behavior: contain;
}

/* ================================
   Typography
   ================================ */
h1, h2, h3, h4, h5, h6 {
  font-weight: var(--font-weight-bold);
  line-height: var(--line-height-tight);
  margin-bottom: var(--space-md);
}

h1 { font-size: var(--font-size-5xl); }
h2 { font-size: var(--font-size-4xl); }
h3 { font-size: var(--font-size-3xl); }
h4 { font-size: var(--font-size-2xl); }
h5 { font-size: var(--font-size-xl); }
h6 { font-size: var(--font-size-lg); }

p {
  margin-bottom: var(--space-md);
}

a {
  color: var(--color-primary);
  text-decoration: none;
  transition: color var(--transition-fast);
}

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

/* Focus states for accessibility */
:focus-visible {
  outline: 2px solid var(--color-primary);
  outline-offset: 2px;
}

/* Remove default focus for mouse users */
:focus:not(:focus-visible) {
  outline: none;
}

/* ================================
   Layout
   ================================ */
.container {
  max-width: var(--container-max-width);
  margin: 0 auto;
  padding: 0 var(--container-padding);
}

main {
  min-height: calc(100vh - var(--nav-height));
}

/* ================================
   Navigation
   ================================ */
.nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  height: var(--nav-height);
  background-color: rgba(26, 26, 26, 0.95);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--color-charcoal-light);
  z-index: var(--z-fixed);
}

.nav__container {
  max-width: var(--container-max-width);
  height: 100%;
  margin: 0 auto;
  padding: 0 var(--container-padding);
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.nav__logo {
  font-size: var(--font-size-xl);
  font-weight: var(--font-weight-bold);
  color: var(--color-text);
  letter-spacing: 0.05em;
}

.nav__links {
  display: none;
  gap: var(--space-xl);
  align-items: center;
}

.nav__link {
  color: var(--color-text);
  font-size: var(--font-size-base);
  font-weight: var(--font-weight-medium);
  transition: color var(--transition-fast);
  background: none;
  border: none;
  cursor: pointer;
}

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

.nav__link--auth {
  padding: var(--space-sm) var(--space-lg);
  background-color: var(--color-primary);
  color: var(--color-charcoal);
  border-radius: var(--radius-md);
}

.nav__link--auth:hover {
  background-color: var(--color-primary-hover);
  color: var(--color-charcoal);
}

/* Mobile menu toggle */
.nav__toggle {
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  width: 40px;
  height: 40px;
  background: none;
  border: none;
  cursor: pointer;
  padding: var(--space-sm);
}

.nav__toggle-icon,
.nav__toggle-icon::before,
.nav__toggle-icon::after {
  display: block;
  width: 24px;
  height: 2px;
  background-color: var(--color-text);
  transition: transform var(--transition-base);
}

.nav__toggle-icon::before,
.nav__toggle-icon::after {
  content: '';
  position: absolute;
}

.nav__toggle-icon::before {
  transform: translateY(-8px);
}

.nav__toggle-icon::after {
  transform: translateY(8px);
}

.nav__toggle[aria-expanded="true"] .nav__toggle-icon {
  background-color: transparent;
}

.nav__toggle[aria-expanded="true"] .nav__toggle-icon::before {
  transform: rotate(45deg);
}

.nav__toggle[aria-expanded="true"] .nav__toggle-icon::after {
  transform: rotate(-45deg);
}

/* Mobile menu */
.nav__mobile {
  position: absolute;
  top: var(--nav-height);
  left: 0;
  right: 0;
  background-color: var(--color-charcoal);
  border-bottom: 1px solid var(--color-charcoal-light);
  padding: var(--space-lg) var(--container-padding);
  display: flex;
  flex-direction: column;
  gap: var(--space-md);
}

.nav__mobile-link {
  color: var(--color-text);
  font-size: var(--font-size-lg);
  font-weight: var(--font-weight-medium);
  padding: var(--space-md);
  border-radius: var(--radius-md);
  transition: background-color var(--transition-fast);
  background: none;
  border: none;
  cursor: pointer;
  text-align: left;
  width: 100%;
}

.nav__mobile-link:hover {
  background-color: var(--color-charcoal-light);
}

.nav__mobile-link--auth {
  background-color: var(--color-primary);
  color: var(--color-charcoal);
}

.nav__mobile-link--auth:hover {
  background-color: var(--color-primary-hover);
}

/* Desktop navigation */
@media (min-width: 768px) {
  .nav__links {
    display: flex;
  }
  
  .nav__toggle {
    display: none;
  }
  
  .nav__mobile {
    display: none;
  }
}

/* ================================
   Hero Section
   ================================ */
.hero {
  position: relative;
  height: 100vh;
  min-height: 600px;
  display: flex;
  align-items: center;
  justify-content: center;
  overflow: hidden;
}

.hero__background {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  z-index: var(--z-base);
}

.hero__video,
.hero__image,
.hero__model {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.hero__overlay {
  position: relative;
  z-index: calc(var(--z-base) + 1);
  width: 100%;
  height: 100%;
  background: linear-gradient(
    to bottom,
    rgba(26, 26, 26, 0.3),
    rgba(26, 26, 26, 0.7)
  );
  display: flex;
  align-items: center;
  justify-content: center;
}

.hero__content {
  text-align: center;
  max-width: 800px;
  padding: 0 var(--container-padding);
}

.hero__title {
  font-size: var(--font-size-5xl);
  font-weight: var(--font-weight-bold);
  margin-bottom: var(--space-lg);
  opacity: 0;
  transform: translateY(30px);
}

.hero__subtitle {
  font-size: var(--font-size-xl);
  color: var(--color-text-muted);
  margin-bottom: var(--space-2xl);
  opacity: 0;
  transform: translateY(30px);
}

.hero__ctas {
  display: flex;
  gap: var(--space-lg);
  justify-content: center;
  flex-wrap: wrap;
  opacity: 0;
  transform: translateY(30px);
}

.hero__scroll {
  position: absolute;
  bottom: var(--space-2xl);
  left: 50%;
  transform: translateX(-50%);
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: var(--space-sm);
  color: var(--color-text-muted);
  font-size: var(--font-size-sm);
  opacity: 0.7;
  animation: bounce 2s infinite;
}

.hero__scroll-icon {
  width: 24px;
  height: 24px;
}

@keyframes bounce {
  0%, 20%, 50%, 80%, 100% {
    transform: translateY(0);
  }
  40% {
    transform: translateY(-10px);
  }
  60% {
    transform: translateY(-5px);
  }
}

@media (max-width: 768px) {
  .hero__title {
    font-size: var(--font-size-4xl);
  }
  
  .hero__subtitle {
    font-size: var(--font-size-lg);
  }
}

/* ================================
   Buttons
   ================================ */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-sm);
  padding: var(--space-md) var(--space-xl);
  font-size: var(--font-size-base);
  font-weight: var(--font-weight-semibold);
  text-align: center;
  border-radius: var(--radius-md);
  border: none;
  cursor: pointer;
  transition: all var(--transition-fast);
  white-space: nowrap;
}

.btn svg {
  width: 20px;
  height: 20px;
}

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

.btn--primary:hover:not(:disabled) {
  background-color: var(--color-primary-hover);
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
}

.btn--secondary {
  background-color: transparent;
  color: var(--color-text);
  border: 2px solid var(--color-text);
}

.btn--secondary:hover:not(:disabled) {
  background-color: var(--color-text);
  color: var(--color-charcoal);
}

.btn--large {
  padding: var(--space-lg) var(--space-2xl);
  font-size: var(--font-size-lg);
}

.btn--full {
  width: 100%;
}

.btn:disabled {
  opacity: 0.5;
  cursor: not-allowed;
}

/* ================================
   Sections
   ================================ */
section {
  padding: var(--space-4xl) 0;
}

.section__header {
  text-align: center;
  margin-bottom: var(--space-3xl);
}

.section__title {
  font-size: var(--font-size-4xl);
  margin-bottom: var(--space-md);
}

.section__subtitle {
  font-size: var(--font-size-lg);
  color: var(--color-text-muted);
}

/* ================================
   Products Section
   ================================ */
.products {
  background-color: var(--color-charcoal-dark);
}

.products__filters {
  display: flex;
  justify-content: center;
  gap: var(--space-md);
  margin-bottom: var(--space-2xl);
  flex-wrap: wrap;
}

.filter-tab {
  padding: var(--space-sm) var(--space-lg);
  font-size: var(--font-size-base);
  font-weight: var(--font-weight-medium);
  color: var(--color-text-muted);
  background: none;
  border: 2px solid transparent;
  border-radius: var(--radius-md);
  cursor: pointer;
  transition: all var(--transition-fast);
}

.filter-tab:hover {
  color: var(--color-text);
  border-color: var(--color-charcoal-light);
}

.filter-tab--active {
  color: var(--color-charcoal);
  background-color: var(--color-primary);
  border-color: var(--color-primary);
}

.products__grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: var(--space-xl);
}

.products__loading {
  grid-column: 1 / -1;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: var(--space-md);
  padding: var(--space-4xl);
  color: var(--color-text-muted);
}

/* Product card (will be created dynamically) */
.product-card {
  background-color: var(--color-charcoal);
  border-radius: var(--radius-lg);
  overflow: hidden;
  transition: transform var(--transition-base);
}

.product-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
}

.product-card__image {
  width: 100%;
  aspect-ratio: 1 / 1;
  object-fit: cover;
}

.product-card__content {
  padding: var(--space-lg);
}

.product-card__title {
  font-size: var(--font-size-lg);
  font-weight: var(--font-weight-semibold);
  margin-bottom: var(--space-sm);
}

.product-card__price {
  font-size: var(--font-size-xl);
  color: var(--color-primary);
  font-weight: var(--font-weight-bold);
}

/* ================================
   About Section
   ================================ */
.about__grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--space-3xl);
  align-items: center;
}

.about__text {
  font-size: var(--font-size-lg);
  line-height: var(--line-height-relaxed);
  color: var(--color-text-muted);
  margin-bottom: var(--space-lg);
}

.about__image {
  width: 100%;
  border-radius: var(--radius-lg);
}

@media (min-width: 768px) {
  .about__grid {
    grid-template-columns: 1fr 1fr;
  }
}

/* ================================
   CTA Section
   ================================ */
.cta {
  background: linear-gradient(135deg, var(--color-charcoal-dark), var(--color-charcoal-light));
  text-align: center;
}

.cta__title {
  font-size: var(--font-size-4xl);
  margin-bottom: var(--space-lg);
}

.cta__text {
  font-size: var(--font-size-lg);
  color: var(--color-text-muted);
  margin-bottom: var(--space-2xl);
  max-width: 600px;
  margin-left: auto;
  margin-right: auto;
}

/* ================================
   Footer
   ================================ */
.footer {
  background-color: var(--color-charcoal-dark);
  padding: var(--space-3xl) 0 var(--space-xl);
  border-top: 1px solid var(--color-charcoal-light);
}

.footer__grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: var(--space-2xl);
  margin-bottom: var(--space-2xl);
}

.footer__logo {
  font-size: var(--font-size-xl);
  font-weight: var(--font-weight-bold);
  margin-bottom: var(--space-sm);
}

.footer__tagline {
  color: var(--color-text-muted);
}

.footer__heading {
  font-size: var(--font-size-lg);
  font-weight: var(--font-weight-semibold);
  margin-bottom: var(--space-md);
}

.footer__list {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: var(--space-sm);
}

.footer__link {
  color: var(--color-text-muted);
  transition: color var(--transition-fast);
}

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

.footer__bottom {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding-top: var(--space-xl);
  border-top: 1px solid var(--color-charcoal-light);
  flex-wrap: wrap;
  gap: var(--space-md);
}

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

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

.footer__social-link {
  width: 32px;
  height: 32px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--color-text-muted);
  transition: color var(--transition-fast);
}

.footer__social-link:hover {
  color: var(--color-primary);
}

.footer__social-link svg {
  width: 20px;
  height: 20px;
}

/* ================================
   Modal
   ================================ */
.modal {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  z-index: var(--z-modal);
  display: flex;
  align-items: center;
  justify-content: center;
}

.modal__overlay {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background-color: rgba(0, 0, 0, 0.8);
  z-index: var(--z-modal-backdrop);
}

.modal__content {
  position: relative;
  z-index: var(--z-modal);
  background-color: var(--color-charcoal);
  border-radius: var(--radius-lg);
  padding: var(--space-2xl);
  max-width: 480px;
  width: calc(100% - var(--space-xl) * 2);
  max-height: calc(100vh - var(--space-xl) * 2);
  overflow-y: auto;
}

.modal__close {
  position: absolute;
  top: var(--space-md);
  right: var(--space-md);
  width: 32px;
  height: 32px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: none;
  border: none;
  color: var(--color-text-muted);
  cursor: pointer;
  transition: color var(--transition-fast);
}

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

.modal__close svg {
  width: 20px;
  height: 20px;
}

.modal__title {
  font-size: var(--font-size-2xl);
  margin-bottom: var(--space-xl);
}

/* ================================
   Auth Forms
   ================================ */
.auth-tabs {
  display: flex;
  gap: var(--space-sm);
  margin-bottom: var(--space-xl);
  border-bottom: 2px solid var(--color-charcoal-light);
}

.auth-tab {
  flex: 1;
  padding: var(--space-md);
  font-size: var(--font-size-base);
  font-weight: var(--font-weight-medium);
  color: var(--color-text-muted);
  background: none;
  border: none;
  border-bottom: 2px solid transparent;
  cursor: pointer;
  transition: all var(--transition-fast);
  margin-bottom: -2px;
}

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

.auth-tab--active {
  color: var(--color-primary);
  border-bottom-color: var(--color-primary);
}

.auth-form {
  display: flex;
  flex-direction: column;
  gap: var(--space-lg);
}

.form-group {
  display: flex;
  flex-direction: column;
  gap: var(--space-sm);
}

.form-label {
  font-size: var(--font-size-sm);
  font-weight: var(--font-weight-medium);
  color: var(--color-text);
}

.form-input,
.form-textarea {
  padding: var(--space-md);
  font-size: var(--font-size-base);
  font-family: var(--font-sans);
  color: var(--color-text);
  background-color: var(--color-charcoal-light);
  border: 2px solid transparent;
  border-radius: var(--radius-md);
  transition: border-color var(--transition-fast);
}

.form-input:focus,
.form-textarea:focus {
  outline: none;
  border-color: var(--color-primary);
}

.form-textarea {
  resize: vertical;
  min-height: 100px;
}

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

.auth-form__message {
  padding: var(--space-md);
  border-radius: var(--radius-md);
  font-size: var(--font-size-sm);
}

.auth-form__message--error {
  background-color: rgba(255, 68, 68, 0.1);
  color: var(--color-error);
  border: 1px solid var(--color-error);
}

.auth-form__message--success {
  background-color: rgba(68, 255, 68, 0.1);
  color: var(--color-success);
  border: 1px solid var(--color-success);
}

/* ================================
   Utility Classes
   ================================ */
.spinner {
  width: 40px;
  height: 40px;
  border: 3px solid var(--color-charcoal-light);
  border-top-color: var(--color-primary);
  border-radius: 50%;
  animation: spin 0.8s linear infinite;
}

@keyframes spin {
  to {
    transform: rotate(360deg);
  }
}

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

/* Hide elements with [hidden] attribute */
[hidden] {
  display: none !important;
}