/* ==========================================================================
   BULK SMS BD — DESIGN SYSTEM
   Tokens: color, type, spacing, radius, shadow, motion
   ========================================================================== */

:root {
  /* ---- Brand Color Ramp ---- */
  --color-purple-900: #4A0E1C;
  --color-purple-700: #F62440;
  --color-purple-500: #FF4D68;
  --color-indigo-700: #AD1530;
  --color-indigo-500: #D8425A;
  --color-teal-500: #96602A;
  --color-teal-400: #C9832A;
  --color-mint-300: #E0A94F;
  --color-mint-200: #F4CE93;
  --color-tan-200: #FFE5BF;
  --color-red-600: #D81B37;

  /* ---- Neutral Ramp ---- */
  --color-ink-950: #1B120D;
  --color-ink-900: #241811;
  --color-ink-800: #2E1F16;
  --color-ink-600: #6B5647;
  --color-ink-400: #9C8873;
  --color-mist-100: #FFFAF3;
  --color-mist-200: #FFF2DB;
  --color-white: #FFFFFF;

  /* ---- Semantic — Light Mode (default) ---- */
  --bg-base: var(--color-mist-100);
  --bg-surface: var(--color-white);
  --bg-surface-alt: var(--color-mist-200);
  --bg-inverse: var(--color-ink-950);
  --text-primary: var(--color-ink-950);
  --text-secondary: #6B5647;
  --text-inverse: var(--color-mist-100);
  --text-on-accent: var(--color-white);
  --border-subtle: rgba(27, 18, 13, 0.12);
  --border-strong: rgba(27, 18, 13, 0.28);
  --accent-primary: var(--color-purple-700);
  --accent-secondary: var(--color-indigo-700);
  --accent-teal: var(--color-teal-500);
  --accent-mint: var(--color-mint-300);
  --focus-ring: var(--color-purple-700);

  --glass-bg: rgba(255, 250, 243, 0.7);
  --glass-border: rgba(255, 250, 243, 0.5);
  --glow-teal: 0 0 32px rgba(246, 36, 64, 0.35);
  --shadow-sm: 0 1px 2px rgba(27, 18, 13, 0.07), 0 1px 1px rgba(27, 18, 13, 0.04);
  --shadow-md: 0 4px 12px rgba(27, 18, 13, 0.11), 0 2px 4px rgba(27, 18, 13, 0.06);
  --shadow-lg: 0 12px 32px rgba(27, 18, 13, 0.15), 0 4px 10px rgba(27, 18, 13, 0.08);
  --shadow-glass: 0 8px 32px rgba(27, 18, 13, 0.13), inset 0 1px 0 rgba(255,255,255,0.55);

  /* ---- Typography ---- */
  --font-bn: 'Noto Sans Bengali', sans-serif;
  --font-en: 'Manrope', sans-serif;

  --fs-xs: clamp(0.75rem, 0.72rem + 0.15vw, 0.8125rem);
  --fs-sm: clamp(0.875rem, 0.84rem + 0.18vw, 0.9375rem);
  --fs-base: clamp(1rem, 0.96rem + 0.2vw, 1.0625rem);
  --fs-md: clamp(1.125rem, 1.06rem + 0.32vw, 1.25rem);
  --fs-lg: clamp(1.375rem, 1.27rem + 0.5vw, 1.625rem);
  --fs-xl: clamp(1.75rem, 1.55rem + 1vw, 2.25rem);
  --fs-2xl: clamp(2.25rem, 1.9rem + 1.75vw, 3.25rem);
  --fs-3xl: clamp(2.75rem, 2.2rem + 2.75vw, 4.5rem);

  --lh-tight: 1.15;
  --lh-snug: 1.35;
  --lh-normal: 1.6;
  --lh-relaxed: 1.75;

  /* ---- Spacing scale (8px grid, 4px half-step) ---- */
  --space-1: 4px;
  --space-2: 8px;
  --space-3: 16px;
  --space-4: 24px;
  --space-5: 32px;
  --space-6: 48px;
  --space-7: 64px;
  --space-8: 96px;
  --space-9: 128px;

  /* ---- Radius ---- */
  --radius-sm: 4px;
  --radius-md: 8px;
  --radius-lg: 16px;
  --radius-xl: 24px;
  --radius-full: 9999px;

  /* ---- Motion ---- */
  --ease-out: cubic-bezier(0.16, 1, 0.3, 1);
  --ease-in-out: cubic-bezier(0.65, 0, 0.35, 1);
  --dur-fast: 150ms;
  --dur-base: 250ms;
  --dur-slow: 450ms;

  /* ---- Layout ---- */
  --container-max: 1800px;
  --container-pad: clamp(20px, 3.2vw, 72px);
  --nav-height: 76px;
}

[data-theme="dark"] {
  --bg-base: var(--color-ink-950);
  --bg-surface: var(--color-ink-900);
  --bg-surface-alt: var(--color-ink-800);
  --bg-inverse: var(--color-mist-100);
  --text-primary: var(--color-mist-100);
  --text-secondary: #C9AD87;
  --text-inverse: var(--color-ink-950);
  --border-subtle: rgba(255, 250, 243, 0.10);
  --border-strong: rgba(255, 250, 243, 0.20);
  --accent-primary: var(--color-purple-500);
  --accent-secondary: var(--color-red-600);
  --accent-teal: var(--color-mint-300);
  --accent-mint: var(--color-mint-200);
  --focus-ring: var(--color-purple-500);
  --glass-bg: rgba(27, 18, 13, 0.6);
  --glass-border: rgba(255, 250, 243, 0.10);
  --shadow-glass: 0 8px 32px rgba(0,0,0,0.45), inset 0 1px 0 rgba(255,255,255,0.05);
}

/* ---- Reset ---- */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; -webkit-text-size-adjust: 100%; }
@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 {
  font-family: var(--font-en);
  background: var(--bg-base);
  color: var(--text-primary);
  line-height: var(--lh-normal);
  font-size: var(--fs-base);
  -webkit-font-smoothing: antialiased;
  transition: background-color var(--dur-base) var(--ease-out), color var(--dur-base) var(--ease-out);
}

:lang(bn) { font-family: var(--font-bn); }

h1, h2, h3, h4 { line-height: var(--lh-tight); font-weight: 800; letter-spacing: -0.01em; }
h1 { font-size: var(--fs-3xl); }
h2 { font-size: var(--fs-2xl); }
h3 { font-size: var(--fs-xl); }
h4 { font-size: var(--fs-md); }
p { color: var(--text-secondary); }
a { color: inherit; text-decoration: none; }
img, svg { max-width: 100%; display: block; }
button { font-family: inherit; cursor: pointer; border: none; background: none; color: inherit; }

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

.container {
  max-width: var(--container-max);
  margin-inline: auto;
  padding-inline: var(--container-pad);
}

.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;
}

.skip-link {
  position: absolute; top: -100px; left: var(--space-3);
  background: var(--accent-primary); color: var(--text-on-accent);
  padding: var(--space-2) var(--space-4); border-radius: var(--radius-md);
  z-index: 1000; transition: top var(--dur-fast) var(--ease-out);
}
.skip-link:focus { top: var(--space-3); }