/* ================================================
   iBioKaare Design System — Global Tokens & Reset
   ================================================ */

@import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700;800&family=Outfit:wght@400;500;600;700;800;900&display=swap');

:root {
  /* ── Color Palette ── */
  --clr-bg-primary:    #0a1628;
  --clr-bg-secondary:  #0f1f3d;
  --clr-bg-surface:    #162040;
  --clr-bg-elevated:   #1a2a4a;
  --clr-bg-glass:      rgba(22, 32, 64, 0.65);

  --clr-accent:        #3b82f6;
  --clr-accent-hover:  #2563eb;
  --clr-accent-glow:   rgba(59, 130, 246, 0.35);
  --clr-accent-soft:   rgba(59, 130, 246, 0.12);

  --clr-text-primary:  #f1f5f9;
  --clr-text-secondary:#94a3b8;
  --clr-text-muted:    #64748b;

  --clr-border:        rgba(255, 255, 255, 0.06);
  --clr-border-hover:  rgba(255, 255, 255, 0.12);
  --clr-divider:       rgba(255, 255, 255, 0.04);

  --clr-success:       #10b981;
  --clr-warning:       #f59e0b;
  --clr-danger:        #ef4444;

  /* ── Gradient Presets ── */
  --grad-hero:         linear-gradient(135deg, #0a1628 0%, #1a1a4e 40%, #0f2847 70%, #0a1628 100%);
  --grad-accent:       linear-gradient(135deg, #3b82f6, #8b5cf6);
  --grad-card-glow:    linear-gradient(135deg, rgba(59,130,246,0.15), rgba(139,92,246,0.08));

  /* ── Typography ── */
  --font-heading: 'Outfit', sans-serif;
  --font-body:    'Inter', sans-serif;

  --fs-xs:   0.75rem;
  --fs-sm:   0.875rem;
  --fs-base: 1rem;
  --fs-md:   1.125rem;
  --fs-lg:   1.25rem;
  --fs-xl:   1.5rem;
  --fs-2xl:  2rem;
  --fs-3xl:  2.5rem;
  --fs-4xl:  3.25rem;
  --fs-5xl:  4rem;

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

  /* ── Radii ── */
  --radius-sm: 8px;
  --radius-md: 12px;
  --radius-lg: 16px;
  --radius-xl: 24px;
  --radius-full: 9999px;

  /* ── Shadows ── */
  --shadow-sm:  0 1px 3px rgba(0,0,0,0.3);
  --shadow-md:  0 4px 12px rgba(0,0,0,0.4);
  --shadow-lg:  0 8px 32px rgba(0,0,0,0.5);
  --shadow-xl:  0 16px 48px rgba(0,0,0,0.6);
  --shadow-glow: 0 0 30px var(--clr-accent-glow);

  /* ── Transitions ── */
  --ease-out:   cubic-bezier(0.22, 1, 0.36, 1);
  --ease-spring: cubic-bezier(0.34, 1.56, 0.64, 1);
  --duration-fast: 0.15s;
  --duration-normal: 0.3s;
  --duration-slow: 0.5s;

  /* ── Z-Index Stack ── */
  --z-base:    1;
  --z-sidebar: 100;
  --z-header:  200;
  --z-overlay: 300;
  --z-modal:   400;
  --z-toast:   500;

  /* ── Layout ── */
  --sidebar-width:  280px;
  --sidebar-collapsed: 0px;
  --header-height: 64px;
  --max-content:   1280px;
}

/* ── Light Mode Theme ── */
[data-theme="light"] {
  --clr-bg-primary:    #f3f4f6;
  --clr-bg-secondary:  #ffffff;
  --clr-bg-surface:    #ffffff;
  --clr-bg-elevated:   #e5e7eb;
  --clr-bg-glass:      rgba(255, 255, 255, 0.9);

  --clr-accent:        #2563eb;
  --clr-accent-hover:  #1d4ed8;
  --clr-accent-glow:   rgba(37, 99, 235, 0.25);
  --clr-accent-soft:   rgba(37, 99, 235, 0.12);

  --clr-text-primary:  #111827;
  --clr-text-secondary:#4b5563;
  --clr-text-muted:    #6b7280;

  --clr-border:        rgba(0, 0, 0, 0.15);
  --clr-border-hover:  rgba(0, 0, 0, 0.3);
  --clr-divider:       rgba(0, 0, 0, 0.08);

  --clr-success:       #059669;
  --clr-warning:       #d97706;
  --clr-danger:        #dc2626;

  --grad-hero:         linear-gradient(135deg, #f3f4f6 0%, #e0e7ff 40%, #dbeafe 70%, #f3f4f6 100%);
  --grad-accent:       linear-gradient(135deg, #2563eb, #4f46e5);
  --grad-card-glow:    linear-gradient(135deg, rgba(37,99,235,0.1), rgba(79,70,229,0.05));

  --shadow-sm:  0 1px 3px rgba(0,0,0,0.1);
  --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);
  --shadow-glow: 0 0 25px rgba(37,99,235,0.3);
}


/* ── Theme Toggle Button ── */
.theme-toggle {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 36px;
  height: 36px;
  border-radius: var(--radius-sm);
  background: var(--clr-bg-surface);
  border: 1px solid var(--clr-border);
  color: var(--clr-text-secondary);
  cursor: pointer;
  transition: all var(--duration-fast) var(--ease-out);
  flex-shrink: 0;
  position: relative;
  overflow: hidden;
}

.theme-toggle:hover {
  color: var(--clr-accent);
  border-color: var(--clr-accent);
  background: var(--clr-accent-soft);
  transform: scale(1.05);
}

.theme-toggle svg {
  width: 18px;
  height: 18px;
  transition: transform 0.4s var(--ease-spring), opacity 0.2s;
}

.theme-toggle__sun,
.theme-toggle__moon {
  position: absolute;
  display: flex;
  align-items: center;
  justify-content: center;
}

/* Dark mode (default): show sun icon */
.theme-toggle__sun {
  opacity: 1;
  transform: rotate(0deg) scale(1);
}
.theme-toggle__moon {
  opacity: 0;
  transform: rotate(-90deg) scale(0.5);
}

/* Light mode: show moon icon */
[data-theme="light"] .theme-toggle__sun {
  opacity: 0;
  transform: rotate(90deg) scale(0.5);
}
[data-theme="light"] .theme-toggle__moon {
  opacity: 1;
  transform: rotate(0deg) scale(1);
}

/* ── Theme Transition ── */
html[data-theme] body,
html[data-theme] .navbar,
html[data-theme] .topbar,
html[data-theme] .sidebar,
html[data-theme] .class-card,
html[data-theme] .feature-card,
html[data-theme] .chapter-card,
html[data-theme] .generate-card,
html[data-theme] .welcome-quick-card {
  transition: background-color 0.35s var(--ease-out),
              color 0.35s var(--ease-out),
              border-color 0.35s var(--ease-out),
              box-shadow 0.35s var(--ease-out);
}

/* ── 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: var(--fs-base);
  line-height: 1.6;
  color: var(--clr-text-primary);
  background-color: var(--clr-bg-primary);
  overflow-x: hidden;
}

h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-heading);
  font-weight: 700;
  line-height: 1.2;
  color: var(--clr-text-primary);
}

a {
  color: var(--clr-accent);
  text-decoration: none;
  transition: color var(--duration-fast) var(--ease-out);
}
a:hover { color: var(--clr-accent-hover); }

img { max-width: 100%; display: block; }

button {
  font-family: var(--font-body);
  cursor: pointer;
  border: none;
  outline: none;
  background: none;
  color: inherit;
}

ul, ol { list-style: none; }

/* ── Utility Classes ── */

.container {
  width: 100%;
  max-width: var(--max-content);
  margin: 0 auto;
  padding: 0 var(--sp-6);
}

.text-gradient {
  background: var(--grad-accent);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.glass {
  background: var(--clr-bg-glass);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border: 1px solid var(--clr-border);
}

.glass-hover:hover {
  background: rgba(22, 32, 64, 0.8);
  border-color: var(--clr-border-hover);
}

/* ── Badge ── */
.badge {
  display: inline-flex;
  align-items: center;
  gap: var(--sp-1);
  padding: var(--sp-1) var(--sp-3);
  font-size: var(--fs-xs);
  font-weight: 600;
  border-radius: var(--radius-full);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}
.badge--live {
  background: rgba(16, 185, 129, 0.15);
  color: var(--clr-success);
  border: 1px solid rgba(16, 185, 129, 0.3);
}
.badge--live::before {
  content: '';
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--clr-success);
  animation: pulse-dot 1.5s ease-in-out infinite;
}
.badge--soon {
  background: rgba(245, 158, 11, 0.12);
  color: var(--clr-warning);
  border: 1px solid rgba(245, 158, 11, 0.25);
}

/* ── Button Styles ── */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--sp-2);
  padding: var(--sp-3) var(--sp-6);
  font-size: var(--fs-sm);
  font-weight: 600;
  border-radius: var(--radius-md);
  transition: all var(--duration-normal) var(--ease-out);
  white-space: nowrap;
}

.btn--primary {
  background: var(--grad-accent);
  color: white;
  box-shadow: 0 4px 15px var(--clr-accent-glow);
}
.btn--primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 25px var(--clr-accent-glow);
}

.btn--outline {
  background: transparent;
  color: var(--clr-accent);
  border: 1.5px solid var(--clr-accent);
}
.btn--outline:hover {
  background: var(--clr-accent-soft);
}

.btn--lg {
  padding: var(--sp-4) var(--sp-8);
  font-size: var(--fs-base);
  border-radius: var(--radius-lg);
}

.btn--sm {
  padding: var(--sp-2) var(--sp-4);
  font-size: var(--fs-xs);
  border-radius: var(--radius-sm);
}

/* ── Section Titles ── */
.section-label {
  font-size: var(--fs-sm);
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.12em;
  color: var(--clr-accent);
  margin-bottom: var(--sp-3);
}

.section-title {
  font-size: var(--fs-3xl);
  font-weight: 800;
  margin-bottom: var(--sp-4);
}

.section-desc {
  font-size: var(--fs-md);
  color: var(--clr-text-secondary);
  max-width: 600px;
}

/* ── Animations ── */
@keyframes pulse-dot {
  0%, 100% { opacity: 1; transform: scale(1); }
  50%      { opacity: 0.5; transform: scale(1.5); }
}

@keyframes fade-up {
  from { opacity: 0; transform: translateY(30px); }
  to   { opacity: 1; transform: translateY(0); }
}

@keyframes fade-in {
  from { opacity: 0; }
  to   { opacity: 1; }
}

@keyframes slide-in-left {
  from { opacity: 0; transform: translateX(-30px); }
  to   { opacity: 1; transform: translateX(0); }
}

@keyframes float {
  0%, 100% { transform: translateY(0px); }
  50%      { transform: translateY(-20px); }
}

@keyframes gradient-shift {
  0%   { background-position: 0% 50%; }
  50%  { background-position: 100% 50%; }
  100% { background-position: 0% 50%; }
}

@keyframes shimmer {
  0%   { background-position: -200% 0; }
  100% { background-position: 200% 0; }
}

.animate-fade-up {
  animation: fade-up var(--duration-slow) var(--ease-out) forwards;
  opacity: 0;
}

.animate-stagger > * {
  opacity: 0;
  animation: fade-up var(--duration-slow) var(--ease-out) forwards;
}

/* ── Scrollbar ── */
::-webkit-scrollbar { width: 6px; height: 6px; }
::-webkit-scrollbar-track { background: var(--clr-bg-primary); }
::-webkit-scrollbar-thumb {
  background: var(--clr-bg-elevated);
  border-radius: var(--radius-full);
}
::-webkit-scrollbar-thumb:hover { background: var(--clr-text-muted); }

/* ── Responsive ── */
@media (max-width: 1024px) {
  :root {
    --fs-4xl: 2.5rem;
    --fs-5xl: 3rem;
    --fs-3xl: 2rem;
  }
}

@media (max-width: 768px) {
  :root {
    --fs-4xl: 2rem;
    --fs-5xl: 2.5rem;
    --fs-3xl: 1.75rem;
    --fs-2xl: 1.5rem;
  }
  .container { padding: 0 var(--sp-4); }
}

@media (max-width: 480px) {
  :root {
    --fs-4xl: 1.75rem;
    --fs-5xl: 2rem;
    --fs-3xl: 1.5rem;
  }
}