/* Core theme foundation: tokens, reset, and accessible defaults. */

:root {
  --page-gutter: clamp(1rem, 4vw, 2.75rem);
  --max-content-width: 1200px;
  --header-height: clamp(4.5rem, 9vw, 5.75rem);
  --filter-offset: calc(var(--header-height) + 0.5rem);

  --color-background: #04050f;
  --color-surface: rgba(15, 23, 42, 0.78);
  --color-surface-alt: rgba(17, 27, 47, 0.68);
  --color-elevated: rgba(30, 41, 59, 0.9);
  --color-border: rgba(148, 163, 184, 0.24);
  --color-divider: rgba(148, 163, 184, 0.12);
  --color-text-primary: #f8fafc;
  --color-text-secondary: #c7d2fe;
  --color-text-muted: #8b9cb7;
  --color-text-inverse: #020617;

  --color-primary: #ff4d67;
  --color-primary-hover: #ff6179;
  --color-secondary: #6366f1;
  --color-accent: #22d3ee;
  --color-success: #34d399;
  --color-warning: #fbbf24;
  --color-danger: #f87171;

  --shadow-xs: 0 4px 16px rgba(15, 23, 42, 0.18);
  --shadow-sm: 0 10px 30px rgba(15, 23, 42, 0.35);
  --shadow-md: 0 20px 48px rgba(15, 23, 42, 0.45);
  --shadow-lg: 0 30px 64px rgba(15, 23, 42, 0.55);

  --radius-xs: 0.5rem;
  --radius-sm: 0.75rem;
  --radius-md: 1rem;
  --radius-lg: 1.5rem;
  --radius-xl: 2rem;
  --radius-pill: 999px;

  --space-xxs: 0.25rem;
  --space-xs: 0.5rem;
  --space-sm: 0.75rem;
  --space-md: 1rem;
  --space-lg: 1.5rem;
  --space-xl: 2rem;
  --space-xxl: 3rem;

  --font-sans: "Inter", system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  --font-heading: "Poppins", "Inter", system-ui, sans-serif;

  --text-xs: 0.75rem;
  --text-sm: 0.875rem;
  --text-base: 1rem;
  --text-md: 1.0625rem;
  --text-lg: 1.25rem;
  --text-xl: 1.5rem;
  --text-2xl: clamp(1.9rem, 4vw, 2.7rem);
  --text-3xl: clamp(2.6rem, 6vw, 3.6rem);

  --transition-fast: 160ms cubic-bezier(.34, .9, .4, 1);
  --transition-medium: 280ms cubic-bezier(.28, .8, .48, 1);
  --transition-slow: 480ms cubic-bezier(.28, .8, .48, 1);

  --blur-soft: 12px;
  --blur-medium: 18px;
  --blur-strong: 26px;

  --card-aspect: 2 / 3;
  --grid-gap: clamp(1rem, 3vw, 1.75rem);

  color-scheme: dark;
}

body.theme-light,
body[data-theme="light"] {
  --color-background: #f5f7fb;
  --color-surface: rgba(255, 255, 255, 0.92);
  --color-surface-alt: rgba(255, 255, 255, 0.78);
  --color-elevated: rgba(255, 255, 255, 0.96);
  --color-border: rgba(15, 23, 42, 0.08);
  --color-divider: rgba(15, 23, 42, 0.08);
  --color-text-primary: #0f172a;
  --color-text-secondary: #1e293b;
  --color-text-muted: #475569;
  --color-primary: #ef476f;
  --color-primary-hover: #ff5d83;
  --color-secondary: #4338ca;
  --color-accent: #0891b2;
  --shadow-sm: 0 8px 28px rgba(15, 23, 42, 0.12);
  --shadow-md: 0 18px 42px rgba(15, 23, 42, 0.15);
  --shadow-lg: 0 26px 52px rgba(15, 23, 42, 0.18);
  color-scheme: light;
}

*,
*::before,
*::after {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
  background-color: var(--color-background);
}

body {
  margin: 0;
  min-height: 100%;
  font-family: var(--font-sans);
  font-size: var(--text-base);
  line-height: 1.6;
  color: var(--color-text-primary);
  background:
    radial-gradient(circle at 0% 0%, rgba(99, 102, 241, 0.18), transparent 40%),
    radial-gradient(circle at 100% 0%, rgba(236, 72, 153, 0.2), transparent 42%),
    radial-gradient(circle at 50% 100%, rgba(14, 165, 233, 0.14), transparent 46%),
    var(--color-background);
  background-attachment: fixed;
  -webkit-font-smoothing: antialiased;
}

body.theme-light,
body[data-theme="light"] {
  background:
    radial-gradient(circle at 0% 0%, rgba(67, 56, 202, 0.08), transparent 42%),
    radial-gradient(circle at 100% 0%, rgba(236, 72, 153, 0.1), transparent 55%),
    linear-gradient(180deg, #f9fbff 0%, #eff3fb 100%);
  color: var(--color-text-primary);
}

body.theme-transition,
body.theme-transition * {
  transition-property: background-color, color, border-color, box-shadow, transform, opacity, filter;
  transition-duration: var(--transition-medium);
  transition-timing-function: var(--transition-medium);
}

@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }

  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
    scroll-behavior: auto !important;
  }

  body.theme-transition,
  body.theme-transition * {
    transition: none !important;
  }
}

img,
picture,
video,
canvas {
  display: block;
  max-width: 100%;
}

button,
input,
select,
textarea {
  font: inherit;
  color: inherit;
  background: none;
  border: none;
}

button {
  cursor: pointer;
}

button:disabled {
  cursor: not-allowed;
  opacity: 0.6;
}

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

a:hover,
a:focus-visible {
  color: var(--color-accent);
}

ul,
ol {
  list-style: none;
  margin: 0;
  padding: 0;
}

p {
  margin: 0;
  color: var(--color-text-muted);
}

h1,
h2,
h3,
h4,
h5,
h6 {
  margin: 0;
  font-family: var(--font-heading);
  font-weight: 600;
  color: var(--color-text-primary);
}

::selection {
  background: rgba(99, 102, 241, 0.35);
  color: var(--color-text-primary);
}

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

.hidden {
  display: none !important;
}

:focus-visible {
  outline: 3px solid var(--color-accent);
  outline-offset: 3px;
  box-shadow: 0 0 0 6px rgba(34, 211, 238, 0.25);
  border-radius: var(--radius-sm);
}

[tabindex="-1"]:focus-visible {
  outline: none;
  box-shadow: none;
}

.glass {
  background: var(--color-surface);
  backdrop-filter: blur(var(--blur-medium)) saturate(140%);
  -webkit-backdrop-filter: blur(var(--blur-medium)) saturate(140%);
  border: 1px solid var(--color-border);
  box-shadow: var(--shadow-sm);
}

.glass-panel {
  background: var(--color-surface-alt);
  backdrop-filter: blur(var(--blur-medium)) saturate(160%);
  -webkit-backdrop-filter: blur(var(--blur-medium)) saturate(160%);
  border: 1px solid var(--color-border);
  box-shadow: var(--shadow-sm);
}

::-webkit-scrollbar {
  width: 10px;
}

::-webkit-scrollbar-track {
  background: rgba(15, 23, 42, 0.45);
  border-radius: 999px;
}

::-webkit-scrollbar-thumb {
  background: rgba(148, 163, 184, 0.45);
  border-radius: 999px;
  border: 2px solid transparent;
}

body.theme-light ::-webkit-scrollbar-track,
body[data-theme="light"] ::-webkit-scrollbar-track {
  background: rgba(148, 163, 184, 0.18);
}

body.theme-light ::-webkit-scrollbar-thumb,
body[data-theme="light"] ::-webkit-scrollbar-thumb {
  background: rgba(99, 102, 241, 0.45);
}