/* ============================================================
   BASE.CSS — Design Tokens & Reset for UseUChat
   ============================================================ */

/* --- Fonts: Cabinet Grotesk (display) + Satoshi (body) from Fontshare --- */
@import url('https://api.fontshare.com/v2/css?f[]=cabinet-grotesk@400,500,700,800&f[]=satoshi@400,500,700&display=swap');

:root {
  /* Typography */
  --font-display: 'Cabinet Grotesk', 'Helvetica Neue', sans-serif;
  --font-body: 'Satoshi', 'Helvetica Neue', sans-serif;

  /* Fluid Type Scale */
  --text-xs:   clamp(0.75rem,  0.7rem  + 0.25vw, 0.875rem);
  --text-sm:   clamp(0.875rem, 0.8rem  + 0.35vw, 1rem);
  --text-base: clamp(1rem,     0.95rem + 0.25vw, 1.125rem);
  --text-lg:   clamp(1.125rem, 1rem    + 0.75vw, 1.5rem);
  --text-xl:   clamp(1.5rem,   1.2rem  + 1.25vw, 2.25rem);
  --text-2xl:  clamp(2rem,     1.2rem  + 2.5vw,  3.5rem);
  --text-3xl:  clamp(2.5rem,   1rem    + 4vw,    5rem);

  /* 4px Spacing System */
  --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;

  /* Brand Colors */
  --color-primary: #007BFF;
  --color-primary-dark: #0056CC;
  --color-primary-light: #4DA3FF;
  --color-accent: #FF6B35;
  --color-accent-hover: #E55A26;

  /* Surfaces */
  --color-bg: #FFFFFF;
  --color-surface: #F8FAFD;
  --color-surface-alt: #F1F5F9;

  /* Dark surfaces */
  --color-dark: #0F172A;
  --color-dark-lighter: #1E293B;

  /* Text */
  --color-text: #1E293B;
  --color-text-muted: #64748B;
  --color-text-faint: #94A3B8;
  --color-text-inverse: #FFFFFF;

  /* Semantic */
  --color-success: #22C55E;
  --color-error: #EF4444;
  --color-warning: #F59E0B;

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

  /* Transitions */
  --transition-interactive: 180ms cubic-bezier(0.16, 1, 0.3, 1);
  --ease-out: cubic-bezier(0.16, 1, 0.3, 1);

  /* Shadows */
  --shadow-sm: 0 1px 2px rgba(15, 23, 42, 0.06);
  --shadow-md: 0 4px 12px rgba(15, 23, 42, 0.08);
  --shadow-lg: 0 12px 32px rgba(15, 23, 42, 0.12);
  --shadow-xl: 0 20px 48px rgba(15, 23, 42, 0.16);

  /* Content widths */
  --content-narrow: 640px;
  --content-default: 960px;
  --content-wide: 1200px;
}

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

html {
  -moz-text-size-adjust: none;
  -webkit-text-size-adjust: none;
  text-size-adjust: none;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  text-rendering: optimizeLegibility;
  scroll-behavior: smooth;
  scroll-padding-top: 80px;
}

body {
  min-height: 100dvh;
  line-height: 1.6;
  font-family: var(--font-body);
  font-size: var(--text-base);
  color: var(--color-text);
  background-color: var(--color-bg);
}

img, picture, video, canvas, svg { display: block; max-width: 100%; height: auto; }
ul[role="list"], ol[role="list"] { list-style: none; }
input, button, textarea, select { font: inherit; color: inherit; }

h1, h2, h3, h4, h5, h6 {
  text-wrap: balance;
  line-height: 1.15;
  font-family: var(--font-display);
}

p, li, figcaption { text-wrap: pretty; max-width: 72ch; }

::selection {
  background: rgba(0, 123, 255, 0.2);
  color: var(--color-text);
}

:focus-visible {
  outline: 2px solid var(--color-primary);
  outline-offset: 3px;
  border-radius: var(--radius-sm);
}

@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;
  }
}

button { cursor: pointer; background: none; border: none; }
a { text-decoration: none; color: inherit; }
table { border-collapse: collapse; width: 100%; }

a, button, [role="button"], input, textarea, select {
  transition: color var(--transition-interactive),
              background var(--transition-interactive),
              border-color var(--transition-interactive),
              box-shadow var(--transition-interactive),
              transform var(--transition-interactive);
}

.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;
}