/**
 * HK Smart Tools Design System — Variables & Design Tokens
 * Domain: hksmarttools.com
 * Premium SaaS / Modern Tools Visual Identity
 */

:root {
  /* Brand Primary Palette (Refined Tech Indigo / Royal Blue) */
  --primary-50: #eff6ff;
  --primary-100: #dbeafe;
  --primary-200: #bfdbfe;
  --primary-300: #93c5fd;
  --primary-400: #60a5fa;
  --primary-500: #3b82f6;
  --primary-600: #2563eb;
  --primary-700: #1d4ed8;
  --primary-800: #1e40af;
  --primary-900: #1e3a8a;
  --primary-950: #172554;

  /* Accent & Complementary */
  --accent-400: #38bdf8;
  --accent-500: #0ea5e9;
  --accent-600: #0284c7;
  --violet-500: #6366f1;
  --teal-500: #14b8a6;
  --emerald-500: #10b981;

  /* Premium Gradients */
  --gradient-primary: linear-gradient(135deg, #2563eb 0%, #0ea5e9 100%);
  --gradient-primary-hover: linear-gradient(135deg, #1d4ed8 0%, #0284c7 100%);
  --gradient-subtle-blue: linear-gradient(135deg, rgba(37, 99, 235, 0.08) 0%, rgba(14, 165, 233, 0.08) 100%);
  --gradient-card-glow: radial-gradient(circle at 50% 0%, rgba(37, 99, 235, 0.04) 0%, transparent 75%);
  --gradient-hero-light: radial-gradient(circle at 50% 15%, rgba(37, 99, 235, 0.08) 0%, rgba(14, 165, 233, 0.04) 40%, transparent 75%);

  /* Semantic Feedback */
  --success: #16a34a;
  --success-bg: #f0fdf4;
  --success-border: #bbf7d0;
  --warning: #d97706;
  --warning-bg: #fffbeb;
  --warning-border: #fde68a;
  --danger: #dc2626;
  --danger-bg: #fef2f2;
  --danger-border: #fecaca;
  --info: #0284c7;
  --info-bg: #f0f9ff;
  --info-border: #bae6fd;

  /* LIGHT MODE (Default) — Sophisticated, Layered, High-Contrast */
  --bg-body: #f6f8fc;
  --bg-surface: #ffffff;
  --bg-surface-elevated: #ffffff;
  --bg-surface-subtle: #edf2f9;
  --bg-surface-tinted: #f0f5ff;
  --bg-input: #ffffff;
  --bg-input-focus: #ffffff;

  /* Borders */
  --border-subtle: #e2e8f2;
  --border-medium: #cbd5e4;
  --border-strong: #94a3b8;
  --border-focus: #2563eb;
  --border-card-hover: #93c5fd;

  /* Text & Iconography */
  --text-primary: #0a1329;       /* Deep Navy text for crystal clarity */
  --text-secondary: #3e4d69;     /* Balanced slate blue-gray */
  --text-muted: #64748b;         /* Muted neutral */
  --text-inverse: #ffffff;

  /* Executive Dark Footer Colors (consistent & rich across both modes) */
  --bg-footer: #090e1a;
  --bg-footer-subtle: #0f172a;
  --border-footer: rgba(255, 255, 255, 0.09);
  --text-footer-primary: #f8fafc;
  --text-footer-secondary: #94a3b8;
  --text-footer-muted: #64748b;

  /* Typography */
  --font-sans: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Oxygen, Ubuntu, Cantarell, "Helvetica Neue", Arial, sans-serif;
  --font-mono: ui-monospace, "SF Mono", "Cascadia Code", "Roboto Mono", Consolas, "Courier New", monospace;

  /* Typography Scale */
  --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 */

  /* 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;

  /* Radius */
  --radius-sm: 0.375rem;
  --radius-md: 0.5rem;
  --radius-lg: 0.75rem;
  --radius-xl: 1rem;
  --radius-2xl: 1.25rem;
  --radius-full: 9999px;

  /* Layered Modern Elevation Shadows */
  --shadow-xs: 0 1px 2px 0 rgba(15, 23, 42, 0.04);
  --shadow-sm: 0 2px 4px -1px rgba(15, 23, 42, 0.05), 0 1px 2px -1px rgba(15, 23, 42, 0.03);
  --shadow-md: 0 4px 12px -2px rgba(15, 23, 42, 0.06), 0 2px 4px -1px rgba(15, 23, 42, 0.04);
  --shadow-lg: 0 10px 24px -4px rgba(15, 23, 42, 0.08), 0 4px 8px -2px rgba(15, 23, 42, 0.04);
  --shadow-xl: 0 20px 32px -8px rgba(15, 23, 42, 0.12), 0 8px 16px -4px rgba(15, 23, 42, 0.06);
  --shadow-focus: 0 0 0 4px rgba(37, 99, 235, 0.15);

  /* Transitions */
  --transition-fast: 150ms cubic-bezier(0.4, 0, 0.2, 1);
  --transition-base: 220ms cubic-bezier(0.4, 0, 0.2, 1);
  --transition-slow: 320ms cubic-bezier(0.4, 0, 0.2, 1);

  /* Maximum Layout Widths */
  --container-max: 1240px;
  --container-narrow: 840px;
}

/* DARK MODE TOKENS — Executive Deep Navy / Slate */
[data-theme="dark"] {
  --bg-body: #080d1a;
  --bg-surface: #0f172a;
  --bg-surface-elevated: #162036;
  --bg-surface-subtle: #131c31;
  --bg-surface-tinted: #14213d;
  --bg-input: #0c1322;
  --bg-input-focus: #111a2e;

  --border-subtle: #1e293b;
  --border-medium: #334155;
  --border-strong: #475569;
  --border-focus: #3b82f6;
  --border-card-hover: #3b82f6;

  --text-primary: #f8fafc;
  --text-secondary: #cbd5e1;
  --text-muted: #94a3b8;
  --text-inverse: #0a1329;

  --primary-50: #172554;
  --primary-100: #1e3a8a;
  --primary-600: #3b82f6;
  --primary-700: #60a5fa;

  --gradient-subtle-blue: linear-gradient(135deg, rgba(59, 130, 246, 0.12) 0%, rgba(14, 165, 233, 0.12) 100%);
  --gradient-card-glow: radial-gradient(circle at 50% 0%, rgba(59, 130, 246, 0.08) 0%, transparent 75%);
  --gradient-hero-light: radial-gradient(circle at 50% 15%, rgba(37, 99, 235, 0.16) 0%, rgba(14, 165, 233, 0.08) 45%, transparent 75%);

  --success-bg: #064e3b;
  --success-border: #047857;
  --warning-bg: #451a03;
  --warning-border: #78350f;
  --danger-bg: #450a0a;
  --danger-border: #7f1d1d;
  --info-bg: #082f49;
  --info-border: #0369a1;

  --bg-footer: #060911;
  --bg-footer-subtle: #0a0f1d;
  --border-footer: rgba(255, 255, 255, 0.06);

  --shadow-xs: 0 1px 2px 0 rgba(0, 0, 0, 0.3);
  --shadow-sm: 0 2px 4px -1px rgba(0, 0, 0, 0.4);
  --shadow-md: 0 6px 16px -2px rgba(0, 0, 0, 0.5);
  --shadow-lg: 0 12px 28px -4px rgba(0, 0, 0, 0.6);
  --shadow-xl: 0 24px 36px -8px rgba(0, 0, 0, 0.7);
  --shadow-focus: 0 0 0 4px rgba(59, 130, 246, 0.25);
}