/* ============================================================
   AEOGAE Design System — 2025
   Shared CSS variables, base styles, components
   ============================================================ */

/* ---------- CSS Custom Properties ---------- */
:root {
  /* Colors — Light Mode */
  --color-bg:             #F8FAFC;
  --color-bg-alt:         #F1F5F9;
  --color-surface:        #FFFFFF;
  --color-surface-glass:  rgba(255, 255, 255, 0.55);
  --color-border:         rgba(0, 0, 0, 0.06);
  --color-text:           #0F172A;
  --color-text-secondary: #475569;
  --color-text-tertiary:  #94A3B8;
  --color-primary:        #4F46E5;
  --color-primary-hover:  #4338CA;
  --color-accent:         #7C3AED;
  --color-accent-light:   rgba(124, 58, 237, 0.10);
  --color-gradient-start: #4F46E5;
  --color-gradient-end:   #7C3AED;
  --color-success:        #10B981;
  --color-warning:        #F59E0B;
  --color-error:          #EF4444;

  /* Glass */
  --glass-bg:             rgba(255, 255, 255, 0.60);
  --glass-border:         rgba(255, 255, 255, 0.25);
  --glass-blur:           20px;

  /* Shadows */
  --shadow-sm:   0 1px 2px rgba(0, 0, 0, 0.05);
  --shadow-md:   0 4px 12px rgba(0, 0, 0, 0.07);
  --shadow-lg:   0 12px 40px rgba(0, 0, 0, 0.10);
  --shadow-xl:   0 24px 60px rgba(0, 0, 0, 0.12);

  /* Typography */
  --font-sans:   'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
  --font-mono:   'SF Mono', 'Fira Code', 'Fira Mono', 'Roboto Mono', monospace;

  --text-xs:     0.75rem;    /* 12px */
  --text-sm:     0.875rem;   /* 14px */
  --text-base:   1rem;       /* 16px */
  --text-lg:     1.125rem;   /* 18px */
  --text-xl:     1.25rem;    /* 20px */
  --text-2xl:    1.5rem;     /* 24px */
  --text-3xl:    1.875rem;   /* 30px */
  --text-4xl:    2.25rem;    /* 36px */
  --text-5xl:    3rem;       /* 48px */
  --text-6xl:    3.75rem;    /* 60px */
  --text-7xl:    4.5rem;     /* 72px */

  --leading-tight:   1.15;
  --leading-normal:  1.5;
  --leading-relaxed: 1.7;

  --tracking-tight:  -0.025em;
  --tracking-normal: 0;
  --tracking-wide:   0.05em;

  /* Spacing */
  --space-1:  0.25rem;
  --space-2:  0.5rem;
  --space-3:  0.75rem;
  --space-4:  1rem;
  --space-5:  1.25rem;
  --space-6:  1.5rem;
  --space-8:  2rem;
  --space-10: 2.5rem;
  --space-12: 3rem;
  --space-16: 4rem;
  --space-20: 5rem;
  --space-24: 6rem;
  --space-32: 8rem;

  /* Border Radius */
  --radius-sm:   0.375rem;
  --radius-md:   0.5rem;
  --radius-lg:   0.75rem;
  --radius-xl:   1rem;
  --radius-2xl:  1.5rem;
  --radius-full: 9999px;

  /* Transitions */
  --ease-out:      cubic-bezier(0.16, 1, 0.3, 1);
  --ease-spring:   cubic-bezier(0.34, 1.56, 0.64, 1);
  --ease-smooth:   cubic-bezier(0.4, 0, 0.2, 1);
  --duration-fast:   150ms;
  --duration-normal: 300ms;
  --duration-slow:   500ms;

  /* Layout */
  --container-max:   1200px;
  --container-narrow: 800px;
  --header-height:   72px;
}

/* ---------- Dark Mode ---------- */
@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --color-bg:             #0F172A;
    --color-bg-alt:         #1E293B;
    --color-surface:        #1E293B;
    --color-surface-glass:  rgba(30, 41, 59, 0.60);
    --color-border:         rgba(255, 255, 255, 0.08);
    --color-text:           #F1F5F9;
    --color-text-secondary: #94A3B8;
    --color-text-tertiary:  #64748B;
    --color-primary:        #818CF8;
    --color-primary-hover:  #A5B4FC;
    --color-accent:         #A78BFA;
    --color-accent-light:   rgba(167, 139, 250, 0.12);

    --glass-bg:             rgba(30, 41, 59, 0.65);
    --glass-border:         rgba(255, 255, 255, 0.08);

    --shadow-sm:   0 1px 2px rgba(0, 0, 0, 0.3);
    --shadow-md:   0 4px 12px rgba(0, 0, 0, 0.4);
    --shadow-lg:   0 12px 40px rgba(0, 0, 0, 0.5);
    --shadow-xl:   0 24px 60px rgba(0, 0, 0, 0.6);
  }
}

[data-theme="dark"] {
  --color-bg:             #0F172A;
  --color-bg-alt:         #1E293B;
  --color-surface:        #1E293B;
  --color-surface-glass:  rgba(30, 41, 59, 0.60);
  --color-border:         rgba(255, 255, 255, 0.08);
  --color-text:           #F1F5F9;
  --color-text-secondary: #94A3B8;
  --color-text-tertiary:  #64748B;
  --color-primary:        #818CF8;
  --color-primary-hover:  #A5B4FC;
  --color-accent:         #A78BFA;
  --color-accent-light:   rgba(167, 139, 250, 0.12);

  --glass-bg:             rgba(30, 41, 59, 0.65);
  --glass-border:         rgba(255, 255, 255, 0.08);

  --shadow-sm:   0 1px 2px rgba(0, 0, 0, 0.3);
  --shadow-md:   0 4px 12px rgba(0, 0, 0, 0.4);
  --shadow-lg:   0 12px 40px rgba(0, 0, 0, 0.5);
  --shadow-xl:   0 24px 60px rgba(0, 0, 0, 0.6);
}

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

html {
  font-size: 16px;
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}

body {
  font-family: var(--font-sans);
  font-size: var(--text-base);
  line-height: var(--leading-normal);
  color: var(--color-text);
  background-color: var(--color-bg);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  overflow-x: hidden;
}

img, video, svg {
  display: block;
  max-width: 100%;
  height: auto;
}

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

h1, h2, h3, h4, h5, h6 {
  line-height: var(--leading-tight);
  letter-spacing: var(--tracking-tight);
  color: var(--color-text);
  font-weight: 700;
}

p {
  color: var(--color-text-secondary);
  line-height: var(--leading-relaxed);
}

ul, ol {
  list-style: none;
}

button {
  cursor: pointer;
  border: none;
  background: transparent;
  font-family: inherit;
  font-size: inherit;
}

input, textarea, select {
  font-family: inherit;
  font-size: inherit;
}

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

/* ---------- Layout ---------- */
.container {
  width: 100%;
  max-width: var(--container-max);
  margin: 0 auto;
  padding: 0 var(--space-6);
}

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

.section {
  padding: var(--space-24) 0;
}

.section--alt {
  background: var(--color-bg-alt);
}

/* ---------- Typography Utilities ---------- */
.text-gradient {
  background: linear-gradient(135deg, var(--color-gradient-start), var(--color-gradient-end));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.text-center { text-align: center; }
.text-left   { text-align: left; }

.section-label {
  display: inline-block;
  font-size: var(--text-sm);
  font-weight: 600;
  letter-spacing: var(--tracking-wide);
  text-transform: uppercase;
  color: var(--color-primary);
  margin-bottom: var(--space-4);
}

.section-title {
  font-size: var(--text-4xl);
  font-weight: 800;
  margin-bottom: var(--space-6);
}

.section-desc {
  font-size: var(--text-lg);
  color: var(--color-text-secondary);
  max-width: 640px;
  margin: 0 auto var(--space-12);
}

@media (min-width: 768px) {
  .section-title {
    font-size: var(--text-5xl);
  }
  .section-desc {
    font-size: var(--text-xl);
  }
}

/* ---------- Glass Card ---------- */
.glass-card {
  background: var(--glass-bg);
  backdrop-filter: blur(var(--glass-blur));
  -webkit-backdrop-filter: blur(var(--glass-blur));
  border: 1px solid var(--glass-border);
  border-radius: var(--radius-xl);
  padding: var(--space-8);
  box-shadow: var(--shadow-md);
  transition: transform var(--duration-normal) var(--ease-out),
              box-shadow var(--duration-normal) var(--ease-out);
}

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

/* ---------- Buttons ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-2);
  font-weight: 600;
  font-size: var(--text-base);
  padding: var(--space-3) var(--space-6);
  border-radius: var(--radius-lg);
  transition: all var(--duration-normal) var(--ease-spring);
  white-space: nowrap;
  user-select: none;
  -webkit-user-select: none;
}

.btn:active {
  transform: scale(0.96);
}

.btn--primary {
  background: linear-gradient(135deg, var(--color-gradient-start), var(--color-gradient-end));
  color: #fff;
  box-shadow: 0 4px 14px rgba(79, 70, 229, 0.4);
}

.btn--primary:hover {
  box-shadow: 0 6px 20px rgba(79, 70, 229, 0.5);
  transform: translateY(-2px);
  color: #fff;
}

.btn--secondary {
  background: var(--color-surface);
  color: var(--color-text);
  border: 1px solid var(--color-border);
  box-shadow: var(--shadow-sm);
}

.btn--secondary:hover {
  background: var(--color-bg-alt);
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
  color: var(--color-text);
}

.btn--ghost {
  color: var(--color-primary);
  padding: var(--space-2) var(--space-4);
}

.btn--ghost:hover {
  background: var(--color-accent-light);
}

.btn--lg {
  font-size: var(--text-lg);
  padding: var(--space-4) var(--space-8);
  border-radius: var(--radius-xl);
}

/* ---------- Sticky Header ---------- */
.site-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  height: var(--header-height);
  display: flex;
  align-items: center;
  transition: background var(--duration-normal) var(--ease-smooth),
              box-shadow var(--duration-normal) var(--ease-smooth),
              backdrop-filter var(--duration-normal) var(--ease-smooth);
}

.site-header.scrolled {
  background: var(--glass-bg);
  backdrop-filter: blur(var(--glass-blur));
  -webkit-backdrop-filter: blur(var(--glass-blur));
  box-shadow: var(--shadow-sm);
  border-bottom: 1px solid var(--glass-border);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  width: 100%;
  max-width: var(--container-max);
  margin: 0 auto;
  padding: 0 var(--space-6);
}

.header-logo {
  font-size: var(--text-xl);
  font-weight: 800;
  letter-spacing: var(--tracking-tight);
  color: var(--color-text);
  text-decoration: none;
}

.header-nav {
  display: flex;
  align-items: center;
  gap: var(--space-1);
}

.header-nav a {
  font-size: var(--text-sm);
  font-weight: 500;
  color: var(--color-text-secondary);
  padding: var(--space-2) var(--space-3);
  border-radius: var(--radius-md);
  transition: all var(--duration-fast) var(--ease-smooth);
}

.header-nav a:hover {
  color: var(--color-text);
  background: var(--color-accent-light);
}

/* Mobile menu button */
.menu-toggle {
  display: none;
  width: 44px;
  height: 44px;
  align-items: center;
  justify-content: center;
  border-radius: var(--radius-md);
}

.menu-toggle span {
  display: block;
  width: 20px;
  height: 2px;
  background: var(--color-text);
  transition: all var(--duration-normal) var(--ease-out);
  position: relative;
}
.menu-toggle span::before,
.menu-toggle span::after {
  content: '';
  display: block;
  width: 20px;
  height: 2px;
  background: var(--color-text);
  position: absolute;
  transition: all var(--duration-normal) var(--ease-out);
}
.menu-toggle span::before { top: -6px; }
.menu-toggle span::after  { top: 6px;  }

.menu-toggle.active span { background: transparent; }
.menu-toggle.active span::before { top: 0; transform: rotate(45deg); }
.menu-toggle.active span::after  { top: 0; transform: rotate(-45deg); }

@media (max-width: 768px) {
  .menu-toggle {
    display: flex;
  }
  .header-nav {
    position: fixed;
    top: var(--header-height);
    left: 0;
    right: 0;
    background: var(--glass-bg);
    backdrop-filter: blur(var(--glass-blur));
    -webkit-backdrop-filter: blur(var(--glass-blur));
    flex-direction: column;
    padding: var(--space-6);
    gap: var(--space-2);
    transform: translateY(-110%);
    opacity: 0;
    transition: all var(--duration-normal) var(--ease-out);
    border-bottom: 1px solid var(--glass-border);
  }
  .header-nav.open {
    transform: translateY(0);
    opacity: 1;
  }
  .header-nav a {
    font-size: var(--text-base);
    padding: var(--space-3) var(--space-4);
    width: 100%;
    text-align: center;
  }
}

/* ---------- Grid Utilities ---------- */
.grid {
  display: grid;
  gap: var(--space-8);
}
.grid-2 { grid-template-columns: repeat(2, 1fr); }
.grid-3 { grid-template-columns: repeat(3, 1fr); }
.grid-4 { grid-template-columns: repeat(4, 1fr); }

@media (max-width: 1024px) {
  .grid-4 { grid-template-columns: repeat(2, 1fr); }
  .grid-3 { grid-template-columns: repeat(2, 1fr); }
}
@media (max-width: 640px) {
  .grid-2, .grid-3, .grid-4 { grid-template-columns: 1fr; }
}

/* ---------- Scroll-based Animations ---------- */
.fade-up {
  opacity: 0;
  transform: translateY(40px);
  transition: opacity var(--duration-slow) var(--ease-out),
              transform var(--duration-slow) var(--ease-out);
}
.fade-up.visible {
  opacity: 1;
  transform: translateY(0);
}

.fade-in {
  opacity: 0;
  transition: opacity var(--duration-slow) var(--ease-out);
}
.fade-in.visible {
  opacity: 1;
}

.slide-left {
  opacity: 0;
  transform: translateX(-40px);
  transition: opacity var(--duration-slow) var(--ease-out),
              transform var(--duration-slow) var(--ease-out);
}
.slide-left.visible {
  opacity: 1;
  transform: translateX(0);
}

.slide-right {
  opacity: 0;
  transform: translateX(40px);
  transition: opacity var(--duration-slow) var(--ease-out),
              transform var(--duration-slow) var(--ease-out);
}
.slide-right.visible {
  opacity: 1;
  transform: translateX(0);
}

/* Stagger children */
.stagger > * { transition-delay: calc(var(--i, 0) * 80ms); }

/* ---------- Form Elements ---------- */
.input {
  width: 100%;
  padding: var(--space-3) var(--space-4);
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  color: var(--color-text);
  font-size: var(--text-base);
  transition: border-color var(--duration-fast) var(--ease-smooth),
              box-shadow var(--duration-fast) var(--ease-smooth);
  outline: none;
}

.input:focus {
  border-color: var(--color-primary);
  box-shadow: 0 0 0 3px var(--color-accent-light);
}

.input::placeholder {
  color: var(--color-text-tertiary);
}

textarea.input {
  resize: vertical;
  min-height: 120px;
}

.form-label {
  display: block;
  font-size: var(--text-sm);
  font-weight: 600;
  color: var(--color-text);
  margin-bottom: var(--space-2);
}

/* ---------- Badge / Chip ---------- */
.badge {
  display: inline-flex;
  align-items: center;
  gap: var(--space-1);
  padding: var(--space-1) var(--space-3);
  font-size: var(--text-xs);
  font-weight: 600;
  border-radius: var(--radius-full);
  background: var(--color-accent-light);
  color: var(--color-primary);
}

/* ---------- Divider ---------- */
.divider {
  height: 1px;
  background: var(--color-border);
  border: none;
  margin: var(--space-16) 0;
}

/* ---------- Footer ---------- */
.site-footer {
  background: var(--color-bg-alt);
  border-top: 1px solid var(--color-border);
  padding: var(--space-16) 0 var(--space-8);
}

.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: var(--space-12);
  margin-bottom: var(--space-12);
}

.footer-brand p {
  margin-top: var(--space-4);
  font-size: var(--text-sm);
  line-height: var(--leading-relaxed);
}

.footer-col h4 {
  font-size: var(--text-sm);
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: var(--tracking-wide);
  margin-bottom: var(--space-4);
  color: var(--color-text);
}

.footer-col a {
  display: block;
  font-size: var(--text-sm);
  color: var(--color-text-secondary);
  padding: var(--space-1) 0;
}
.footer-col a:hover {
  color: var(--color-primary);
}

.footer-bottom {
  border-top: 1px solid var(--color-border);
  padding-top: var(--space-8);
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: var(--space-4);
}

.footer-bottom p {
  font-size: var(--text-sm);
  color: var(--color-text-tertiary);
}

@media (max-width: 768px) {
  .footer-grid {
    grid-template-columns: 1fr 1fr;
    gap: var(--space-8);
  }
  .footer-bottom {
    flex-direction: column;
    text-align: center;
  }
}
@media (max-width: 480px) {
  .footer-grid {
    grid-template-columns: 1fr;
  }
}

/* ---------- Back to Top ---------- */
.back-to-top {
  position: fixed;
  bottom: var(--space-8);
  right: var(--space-8);
  width: 48px;
  height: 48px;
  border-radius: var(--radius-full);
  background: var(--color-primary);
  color: #fff;
  display: flex;
  align-items: center;
  justify-content: center;
  opacity: 0;
  transform: translateY(20px);
  transition: all var(--duration-normal) var(--ease-spring);
  z-index: 900;
  box-shadow: var(--shadow-md);
}

.back-to-top.show {
  opacity: 1;
  transform: translateY(0);
}

.back-to-top:hover {
  background: var(--color-primary-hover);
  transform: translateY(-4px);
  color: #fff;
}

/* ---------- Legal Page Layout ---------- */
.legal-page {
  padding-top: calc(var(--header-height) + var(--space-12));
  padding-bottom: var(--space-16);
  min-height: 100vh;
}

.legal-page h1 {
  font-size: var(--text-4xl);
  margin-bottom: var(--space-2);
}

.legal-page .legal-date {
  font-size: var(--text-sm);
  color: var(--color-text-tertiary);
  margin-bottom: var(--space-10);
}

.legal-content {
  font-size: var(--text-base);
  line-height: var(--leading-relaxed);
  color: var(--color-text-secondary);
}

.legal-content h2 {
  font-size: var(--text-xl);
  font-weight: 700;
  color: var(--color-text);
  margin-top: var(--space-10);
  margin-bottom: var(--space-4);
  padding-bottom: var(--space-3);
  border-bottom: 1px solid var(--color-border);
}

.legal-content h3 {
  font-size: var(--text-lg);
  font-weight: 600;
  color: var(--color-text);
  margin-top: var(--space-6);
  margin-bottom: var(--space-3);
}

.legal-content p {
  margin-bottom: var(--space-4);
}

.legal-content ul, .legal-content ol {
  margin-bottom: var(--space-4);
  padding-left: var(--space-6);
}

.legal-content li {
  list-style: disc;
  margin-bottom: var(--space-2);
  color: var(--color-text-secondary);
}

.legal-content ol li {
  list-style: decimal;
}

/* ---------- Tool Page Layout ---------- */
.tool-page {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  align-items: center;
  padding-top: calc(var(--header-height) + var(--space-12));
  padding-bottom: var(--space-16);
  background: linear-gradient(160deg, var(--color-bg) 0%, var(--color-bg-alt) 100%);
}

.tool-card {
  background: var(--glass-bg);
  backdrop-filter: blur(var(--glass-blur));
  -webkit-backdrop-filter: blur(var(--glass-blur));
  border: 1px solid var(--glass-border);
  border-radius: var(--radius-2xl);
  padding: var(--space-10);
  width: 90%;
  max-width: 540px;
  box-shadow: var(--shadow-lg);
  text-align: center;
}

.tool-card h1 {
  font-size: var(--text-3xl);
  margin-bottom: var(--space-6);
}

.tool-card .input {
  margin-bottom: var(--space-4);
}

/* ---------- 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;
  }
  .fade-up, .fade-in, .slide-left, .slide-right {
    opacity: 1;
    transform: none;
  }
}

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

/* Skip link */
.skip-link {
  position: absolute;
  top: -100%;
  left: var(--space-4);
  padding: var(--space-3) var(--space-6);
  background: var(--color-primary);
  color: #fff;
  border-radius: var(--radius-md);
  font-weight: 600;
  z-index: 10000;
  transition: top var(--duration-fast);
}
.skip-link:focus {
  top: var(--space-4);
  color: #fff;
}

/* Screen reader only */
.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;
}