/* =============================================================================
   Flow Studio 2025 - Multi-Theme System
   8 design variations demonstrating 2025 web design trends
   ============================================================================= */

/* =============================================================================
   Theme-Aware CSS Variables (dynamically updated by theme switcher)
   ============================================================================= */
:root {
  /* Theme colors (updated dynamically) */
  --color-primary: #475569;
  --color-primary-light: #64748b;
  --color-primary-dark: #334155;
  --color-accent: #2563eb;
  --color-accent-light: #3b82f6;
  --color-background: #ffffff;
  --color-background-alt: #f8fafc;
  --color-text: #334155;
  --color-text-light: #64748b;
  --color-border: #cbd5e1;

  /* Theme typography (updated dynamically) */
  --font-heading: 'Inter', sans-serif;
  --font-body: 'Inter', sans-serif;
  --font-heading-weight: 600;
  --font-body-weight: 400;

  /* Theme spacing (updated dynamically) */
  --spacing-section: 96px;
  --spacing-card-gap: 24px;

  /* Theme motion (updated dynamically) */
  --motion-duration: 0.25s;
  --motion-easing: cubic-bezier(0.4, 0, 0.2, 1);

  /* Theme gradient (updated dynamically) */
  --gradient-hero: linear-gradient(135deg, #475569 0%, #2563eb 100%);

  /* Static spacing scale */
  --spacing-1: 4px;
  --spacing-2: 8px;
  --spacing-3: 12px;
  --spacing-4: 16px;
  --spacing-5: 20px;
  --spacing-6: 24px;
  --spacing-8: 32px;
  --spacing-10: 40px;
  --spacing-12: 48px;
  --spacing-16: 64px;
  --spacing-20: 80px;
  --spacing-24: 96px;

  /* Static typography scale */
  --font-size-xs: 12px;
  --font-size-sm: 14px;
  --font-size-base: 16px;
  --font-size-md: 18px;
  --font-size-lg: 20px;
  --font-size-xl: 24px;
  --font-size-2xl: 30px;
  --font-size-3xl: 36px;
  --font-size-4xl: 48px;
  --font-size-5xl: 60px;
  --font-size-6xl: 72px;
  --font-size-7xl: 96px;

  /* Static layout values */
  --content-max-width: 1280px;
  --content-narrow-width: 720px;
  --form-max-width: 480px;

  /* Static border radius */
  --radius-sm: 4px;
  --radius-md: 6px;
  --radius-lg: 8px;
  --radius-xl: 12px;
  --radius-2xl: 16px;
  --radius-full: 9999px;

  /* Shadows */
  --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
  --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
  --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
  --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 10px 10px -5px rgba(0, 0, 0, 0.04);
}

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

html {
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-body);
  font-size: var(--font-size-base);
  font-weight: var(--font-body-weight);
  line-height: 1.625;
  color: var(--color-text);
  background-color: var(--color-background);
  transition: background-color var(--motion-duration) var(--motion-easing),
              color var(--motion-duration) var(--motion-easing);
}

/* =============================================================================
   Typography
   ============================================================================= */
h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-heading);
  font-weight: var(--font-heading-weight);
  line-height: 1.25;
  letter-spacing: -0.025em;
  color: var(--color-text);
  transition: color var(--motion-duration) var(--motion-easing);
}

h1 { font-size: var(--font-size-4xl); }
h2 { font-size: var(--font-size-3xl); }
h3 { font-size: var(--font-size-xl); }

p { margin: 0; }

/* =============================================================================
   Theme Switcher
   ============================================================================= */
.theme-switcher {
  position: fixed;
  top: 20px;
  right: 20px;
  z-index: 1000;
  background: var(--color-background);
  border: 2px solid var(--color-border);
  border-radius: var(--radius-xl);
  padding: var(--spacing-4);
  box-shadow: var(--shadow-xl);
  max-width: 320px;
  transition: all var(--motion-duration) var(--motion-easing);
}

.theme-switcher__header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: var(--spacing-3);
  padding-bottom: var(--spacing-3);
  border-bottom: 1px solid var(--color-border);
}

.theme-switcher__title {
  font-size: var(--font-size-sm);
  font-weight: 600;
  color: var(--color-text);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.theme-switcher__close {
  background: none;
  border: none;
  color: var(--color-text-light);
  cursor: pointer;
  font-size: 20px;
  padding: 0;
  width: 24px;
  height: 24px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: var(--radius-sm);
  transition: all 0.2s;
}

.theme-switcher__close:hover {
  background: var(--color-background-alt);
  color: var(--color-text);
}

.theme-switcher__grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: var(--spacing-2);
}

.theme-option {
  padding: var(--spacing-3);
  border: 2px solid var(--color-border);
  border-radius: var(--radius-md);
  background: var(--color-background);
  cursor: pointer;
  transition: all 0.2s;
  text-align: left;
}

.theme-option:hover {
  border-color: var(--color-accent);
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
}

.theme-option.active {
  border-color: var(--color-accent);
  background: var(--color-accent);
  color: white;
}

.theme-option.active .theme-option__name,
.theme-option.active .theme-option__desc {
  color: white;
}

.theme-option__name {
  font-size: var(--font-size-sm);
  font-weight: 600;
  color: var(--color-text);
  margin-bottom: var(--spacing-1);
  display: block;
}

.theme-option__desc {
  font-size: 11px;
  color: var(--color-text-light);
  line-height: 1.4;
  display: block;
}

.theme-toggle-btn {
  position: fixed;
  bottom: 20px;
  right: 20px;
  z-index: 999;
  background: var(--gradient-hero);
  color: white;
  border: none;
  border-radius: var(--radius-full);
  width: 56px;
  height: 56px;
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  box-shadow: var(--shadow-xl);
  transition: all var(--motion-duration) var(--motion-easing);
  font-size: 24px;
}

.theme-toggle-btn:hover {
  transform: scale(1.1) rotate(90deg);
  box-shadow: 0 20px 40px rgba(0, 0, 0, 0.2);
}

/* Hide switcher when closed */
.theme-switcher.hidden {
  opacity: 0;
  pointer-events: none;
  transform: translateY(-10px);
}

/* =============================================================================
   Layout Containers
   ============================================================================= */
.container {
  max-width: var(--content-max-width);
  margin-left: auto;
  margin-right: auto;
  padding-left: var(--spacing-6);
  padding-right: var(--spacing-6);
  width: 100%;
}

.container--narrow {
  max-width: var(--content-narrow-width);
}

.container--form {
  max-width: var(--form-max-width);
}

/* =============================================================================
   Grid System
   ============================================================================= */
.grid {
  display: grid;
  gap: var(--spacing-card-gap);
}

.grid--3 {
  grid-template-columns: 1fr;
}

/* =============================================================================
   Sections
   ============================================================================= */
.section {
  padding-top: calc(var(--spacing-section) * 0.5);
  padding-bottom: calc(var(--spacing-section) * 0.5);
  transition: padding var(--motion-duration) var(--motion-easing);
}

.section--gray {
  background-color: var(--color-background-alt);
  transition: background-color var(--motion-duration) var(--motion-easing);
}

.section--cta {
  background: var(--gradient-hero);
  color: white;
}

.section__header {
  text-align: center;
  margin-bottom: var(--spacing-12);
}

.section__eyebrow {
  font-size: var(--font-size-sm);
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--color-accent);
  margin-bottom: var(--spacing-4);
  transition: color var(--motion-duration) var(--motion-easing);
}

.section__title {
  font-size: var(--font-size-3xl);
  font-weight: var(--font-heading-weight);
  color: var(--color-text);
  max-width: 900px;
  margin-left: auto;
  margin-right: auto;
}

.section--cta .section__title,
.section--cta .section__eyebrow {
  color: white;
}

/* =============================================================================
   Header
   ============================================================================= */
.header {
  padding: var(--spacing-6) 0;
  border-bottom: 1px solid var(--color-border);
  background: var(--color-background);
  transition: all var(--motion-duration) var(--motion-easing);
}

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

.logo {
  font-size: var(--font-size-lg);
  font-weight: 700;
  color: var(--color-text);
  text-decoration: none;
  transition: color var(--motion-duration) var(--motion-easing);
}

.header__nav {
  display: flex;
  gap: var(--spacing-6);
  align-items: center;
}

.nav-link {
  font-size: var(--font-size-base);
  font-weight: 500;
  color: var(--color-text-light);
  text-decoration: none;
  transition: color 0.2s;
}

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

/* =============================================================================
   Buttons
   ============================================================================= */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--spacing-2);
  min-height: 44px;
  padding: var(--spacing-3) var(--spacing-6);
  font-size: var(--font-size-base);
  font-weight: 600;
  font-family: var(--font-body);
  line-height: 1.5;
  text-decoration: none;
  text-align: center;
  border: none;
  border-radius: var(--radius-md);
  cursor: pointer;
  transition: all var(--motion-duration) var(--motion-easing);
  white-space: nowrap;
}

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

.btn--primary:hover {
  background-color: var(--color-accent-light);
  transform: translateY(-2px);
  box-shadow: var(--shadow-lg);
}

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

.btn--secondary:hover {
  background-color: var(--color-background-alt);
  border-color: var(--color-accent);
}

.btn--sm {
  min-height: 36px;
  padding: var(--spacing-2) var(--spacing-4);
  font-size: var(--font-size-sm);
}

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

/* =============================================================================
   Cards
   ============================================================================= */
.card {
  background-color: var(--color-background);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: var(--spacing-6);
  box-shadow: var(--shadow-sm);
  transition: all var(--motion-duration) var(--motion-easing);
}

.card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
  border-color: var(--color-accent-light);
}

.card__icon {
  width: 32px;
  height: 32px;
  color: var(--color-accent);
  margin-bottom: var(--spacing-4);
  transition: all var(--motion-duration) var(--motion-easing);
}

.card:hover .card__icon {
  transform: scale(1.1);
  color: var(--color-accent-light);
}

.card__title {
  font-size: var(--font-size-lg);
  font-weight: 600;
  color: var(--color-text);
  margin-bottom: var(--spacing-3);
}

.card__description {
  font-size: var(--font-size-base);
  line-height: 1.625;
  color: var(--color-text-light);
}

/* =============================================================================
   Hero Section
   ============================================================================= */
.hero {
  padding-top: var(--spacing-section);
  padding-bottom: var(--spacing-section);
  text-align: center;
  position: relative;
  overflow: hidden;
}

.hero__content {
  display: flex;
  flex-direction: column;
  gap: var(--spacing-6);
  align-items: center;
  position: relative;
  z-index: 1;
}

.hero__title {
  font-size: var(--font-size-4xl);
  font-weight: var(--font-heading-weight);
  line-height: 1.15;
  letter-spacing: -0.02em;
  color: var(--color-text);
  max-width: 720px;
  animation: fadeInUp 0.8s ease-out;
}

.hero__subtitle {
  font-size: var(--font-size-xl);
  line-height: 1.4;
  color: var(--color-text-light);
  max-width: 680px;
  animation: fadeInUp 0.8s ease-out 0.1s backwards;
}

.hero__description {
  font-size: var(--font-size-md);
  line-height: 1.625;
  color: var(--color-text-light);
  max-width: 720px;
  animation: fadeInUp 0.8s ease-out 0.2s backwards;
}

.hero__actions {
  display: flex;
  flex-direction: column;
  gap: var(--spacing-4);
  width: 100%;
  max-width: 400px;
  margin-top: var(--spacing-2);
  animation: fadeInUp 0.8s ease-out 0.3s backwards;
}

.hero__note {
  font-size: var(--font-size-sm);
  color: var(--color-text-light);
  font-weight: 500;
  animation: fadeInUp 0.8s ease-out 0.4s backwards;
}

/* =============================================================================
   Agents Section
   ============================================================================= */
.agents {
  display: flex;
  flex-direction: column;
  gap: var(--spacing-6);
}

.agent {
  background-color: var(--color-background);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: var(--spacing-6);
  transition: all var(--motion-duration) var(--motion-easing);
}

.agent:hover {
  transform: translateX(8px);
  border-color: var(--color-accent);
  box-shadow: var(--shadow-md);
}

.agent__name {
  font-size: var(--font-size-xl);
  font-weight: 700;
  color: var(--color-text);
  margin-bottom: var(--spacing-2);
}

.agent__role {
  font-size: var(--font-size-sm);
  font-weight: 600;
  color: var(--color-accent);
  margin-bottom: var(--spacing-3);
}

.agent__description {
  font-size: var(--font-size-base);
  line-height: 1.625;
  color: var(--color-text-light);
}

/* =============================================================================
   Process Section
   ============================================================================= */
.process {
  display: flex;
  flex-direction: column;
  gap: var(--spacing-10);
}

.process__step {
  display: flex;
  gap: var(--spacing-6);
  align-items: flex-start;
}

.process__number {
  flex-shrink: 0;
  width: 48px;
  height: 48px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: var(--font-size-xl);
  font-weight: 700;
  color: white;
  background: var(--color-accent);
  border-radius: var(--radius-full);
  transition: all var(--motion-duration) var(--motion-easing);
}

.process__step:hover .process__number {
  transform: scale(1.15) rotate(360deg);
  background: var(--color-accent-light);
}

.process__content {
  flex: 1;
}

.process__title {
  font-size: var(--font-size-lg);
  font-weight: 600;
  color: var(--color-text);
  margin-bottom: var(--spacing-3);
}

.process__description {
  font-size: var(--font-size-base);
  line-height: 1.625;
  color: var(--color-text-light);
}

/* =============================================================================
   CTA Section
   ============================================================================= */
.cta {
  text-align: center;
}

.cta__title {
  font-size: var(--font-size-3xl);
  font-weight: 700;
  color: white;
  margin-bottom: var(--spacing-4);
}

.cta__subtitle {
  font-size: var(--font-size-md);
  line-height: 1.625;
  color: rgba(255, 255, 255, 0.9);
  margin-bottom: var(--spacing-8);
}

.cta__privacy {
  font-size: var(--font-size-sm);
  color: rgba(255, 255, 255, 0.7);
  margin-top: var(--spacing-6);
}

/* =============================================================================
   Forms
   ============================================================================= */
.form {
  display: flex;
  flex-direction: column;
  gap: var(--spacing-6);
}

.form__group {
  display: flex;
  flex-direction: column;
  gap: var(--spacing-2);
  text-align: left;
}

.form__label {
  font-size: var(--font-size-sm);
  font-weight: 600;
  color: white;
}

.form__input,
.form__select {
  width: 100%;
  min-height: 44px;
  padding: var(--spacing-3) var(--spacing-4);
  font-size: var(--font-size-base);
  font-family: var(--font-body);
  line-height: 1.5;
  color: var(--color-text);
  background-color: white;
  border: 2px solid rgba(255, 255, 255, 0.3);
  border-radius: var(--radius-md);
  transition: all 0.2s;
}

.form__input:focus,
.form__select:focus {
  outline: none;
  border-color: white;
  box-shadow: 0 0 0 3px rgba(255, 255, 255, 0.2);
}

.form__note {
  font-size: var(--font-size-sm);
  color: rgba(255, 255, 255, 0.8);
  text-align: center;
  margin-top: var(--spacing-2);
}

/* =============================================================================
   Footer
   ============================================================================= */
.footer {
  padding: var(--spacing-12) 0;
  border-top: 1px solid var(--color-border);
  background: var(--color-background);
  transition: all var(--motion-duration) var(--motion-easing);
}

.footer__content {
  text-align: center;
}

.footer__text {
  font-size: var(--font-size-sm);
  color: var(--color-text-light);
}

/* =============================================================================
   Animations
   ============================================================================= */
@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(30px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@keyframes fadeIn {
  from { opacity: 0; }
  to { opacity: 1; }
}

/* Scroll reveal animation (applied via JS) */
.scroll-reveal {
  opacity: 0;
  transform: translateY(30px);
  transition: all 0.8s var(--motion-easing);
}

.scroll-reveal.revealed {
  opacity: 1;
  transform: translateY(0);
}

/* =============================================================================
   Theme-Specific Styles
   ============================================================================= */

/* Type Hero - Extra large typography */
.theme-type-hero .hero__title {
  font-size: var(--font-size-6xl);
  font-weight: 800;
  letter-spacing: -0.04em;
}

.theme-type-hero h2 {
  font-size: var(--font-size-5xl);
}

/* 3D Depth - Enhanced shadows and transforms */
.theme-3d-depth .card {
  box-shadow: 0 20px 40px rgba(0, 0, 0, 0.3);
}

.theme-3d-depth .card:hover {
  transform: translateY(-8px) perspective(1000px) rotateX(5deg);
}

/* Scroll Master - Gradient backgrounds */
.theme-scroll-master .hero {
  background: var(--gradient-hero);
}

.theme-scroll-master .hero__title,
.theme-scroll-master .hero__subtitle,
.theme-scroll-master .hero__description,
.theme-scroll-master .hero__note {
  color: white;
}

/* Grid Artist - Asymmetric layouts */
.theme-grid-artist .grid--3 {
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
}

.theme-grid-artist .agents {
  display: grid;
  grid-template-columns: 2fr 1fr;
  gap: var(--spacing-6);
}

.theme-grid-artist .agent:first-child {
  grid-column: 1 / 2;
  grid-row: 1 / 3;
}

/* Motion Flow - Spring animations */
.theme-motion-flow .btn:hover {
  animation: bounce 0.6s ease;
}

@keyframes bounce {
  0%, 100% { transform: translateY(0); }
  50% { transform: translateY(-10px); }
}

/* Dark Vivid - Glow effects */
.theme-dark-vivid .btn--primary {
  box-shadow: 0 0 20px var(--color-accent), var(--shadow-md);
}

.theme-dark-vivid .card {
  border-color: var(--color-accent);
  box-shadow: 0 0 15px rgba(0, 0, 0, 0.5);
}

/* =============================================================================
   Responsive Design
   ============================================================================= */
@media (min-width: 640px) {
  .section {
    padding-top: calc(var(--spacing-section) * 0.67);
    padding-bottom: calc(var(--spacing-section) * 0.67);
  }

  .hero {
    padding-top: var(--spacing-section);
    padding-bottom: var(--spacing-section);
  }

  .hero__actions {
    flex-direction: row;
    justify-content: center;
    width: auto;
  }

  .grid--3 {
    grid-template-columns: repeat(2, 1fr);
  }

  .theme-switcher {
    max-width: 380px;
  }

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

@media (min-width: 1024px) {
  .section {
    padding-top: var(--spacing-section);
    padding-bottom: var(--spacing-section);
  }

  .hero__title {
    font-size: var(--font-size-5xl);
  }

  .section__title {
    font-size: var(--font-size-4xl);
  }

  .grid--3 {
    grid-template-columns: repeat(3, 1fr);
  }

  .agents {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: var(--spacing-6);
  }

  .process {
    gap: var(--spacing-12);
  }

  .theme-type-hero .hero__title {
    font-size: var(--font-size-7xl);
  }
}

/* =============================================================================
   Accessibility
   ============================================================================= */
@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
    scroll-behavior: auto !important;
  }
}

*:focus-visible {
  outline: 3px solid var(--color-accent);
  outline-offset: 2px;
}

*:focus:not(:focus-visible) {
  outline: none;
}

/* =============================================================================
   Showcase Section
   ============================================================================= */
.showcase__intro {
  text-align: center;
  font-size: var(--font-size-md);
  line-height: 1.625;
  color: var(--color-text-light);
  max-width: 720px;
  margin: 0 auto var(--spacing-12);
}

.showcase__grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--spacing-card-gap);
}

.showcase__item {
  background: var(--color-background);
  border: 2px solid var(--color-border);
  border-radius: var(--radius-lg);
  overflow: hidden;
  transition: all var(--motion-duration) var(--motion-easing);
}

.showcase__item:hover {
  transform: translateY(-8px);
  box-shadow: var(--shadow-xl);
  border-color: var(--color-accent);
}

.showcase__item--placeholder {
  opacity: 0.7;
  border-style: dashed;
}

.showcase__item--placeholder:hover {
  opacity: 1;
}

.showcase__preview {
  padding: var(--spacing-8);
}

.showcase__badge {
  display: inline-block;
  padding: var(--spacing-2) var(--spacing-4);
  background: var(--gradient-hero);
  color: white;
  font-size: var(--font-size-sm);
  font-weight: 600;
  border-radius: var(--radius-md);
  margin-bottom: var(--spacing-4);
}

.showcase__title {
  font-size: var(--font-size-2xl);
  font-weight: 700;
  color: var(--color-text);
  margin-bottom: var(--spacing-3);
}

.showcase__description {
  font-size: var(--font-size-base);
  line-height: 1.625;
  color: var(--color-text-light);
  margin-bottom: var(--spacing-4);
}

.showcase__meta {
  display: flex;
  flex-wrap: wrap;
  gap: var(--spacing-2);
  margin-bottom: var(--spacing-4);
}

.showcase__tag {
  padding: var(--spacing-1) var(--spacing-3);
  background: var(--color-background-alt);
  color: var(--color-text-light);
  font-size: var(--font-size-sm);
  font-weight: 500;
  border-radius: var(--radius-sm);
  border: 1px solid var(--color-border);
}

.showcase__link {
  display: inline-flex;
  align-items: center;
  gap: var(--spacing-2);
  color: var(--color-accent);
  font-size: var(--font-size-base);
  font-weight: 600;
  text-decoration: none;
  transition: all 0.2s;
}

.showcase__link:hover {
  gap: var(--spacing-3);
  color: var(--color-accent-light);
}

/* Responsive showcase grid */
@media (min-width: 768px) {
  .showcase__grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (min-width: 1024px) {
  .showcase__grid {
    grid-template-columns: repeat(3, 1fr);
  }
}