/**
 * BASE.CSS - Design System Foundation
 * 
 * Questo file contiene SOLO le fondamenta del design system:
 * - Reset professionale
 * - Design tokens (CSS variables)
 * - Stili globali base
 * - Accessibilità
 * 
 * ⚠️ NON contiene layout, componenti o responsive
 * ⚠️ Questo è il primo file caricato, serve come base per tutti gli altri
 */

/* ============================================
   RESET PROFESSIONALE
   ============================================ */

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

html {
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  text-rendering: optimizeLegibility;
}

body {
  margin: 0;
  padding: 0;
  min-height: 100vh;
}

/* Immagini responsive */
img,
picture,
video,
canvas,
svg {
  display: block;
  max-width: 100%;
  height: auto;
}

/* Liste senza stile di default */
ul,
ol {
  list-style: none;
}

/* Link senza stile di default */
a {
  text-decoration: none;
  color: inherit;
}

/* Button base senza stile */
button {
  background: none;
  border: none;
  padding: 0;
  font: inherit;
  cursor: pointer;
  color: inherit;
}

/* Input base senza stile */
input,
textarea,
select {
  font: inherit;
  color: inherit;
}

/* ============================================
   DESIGN TOKENS - CSS VARIABLES
   ============================================ */

:root {
  /* ============================================
     🎨 COLORI - PALETTE PROFESSIONALE
     ============================================ */

  /* Colori primari */
  --color-primary: #2263c5;
  --color-primary-hover: #1d4ed8;
  --color-primary-light: #dce7fc;
  --color-primary-dark: #164ea3;

  /* Colori secondari */
  --color-secondary: #111827;
  --color-secondary-hover: #1f2937;

  /* Colori semantici */
  --color-success: #28a745;
  --color-success-light: #d4edda;
  --color-success-dark: #218838;

  --color-warning: #f59e0b;
  --color-warning-light: #fef3c7;
  --color-warning-dark: #d97706;

  --color-danger: #dc3545;
  --color-danger-light: #f8d7da;
  --color-danger-dark: #c82333;

  --color-info: #2563eb;
  --color-info-light: #dbeafe;
  --color-info-dark: #1d4ed8;

  /* Background */
  --color-bg: #f3f4f6;
  --color-bg-soft: #e5e7eb;
  --color-bg-card: #ffffff;
  --color-surface: #ffffff;

  /* Border */
  --color-border: #d1d5db;
  --color-border-subtle: #e5e7eb;
  --color-border-strong: #d1d5db;

  /* Testo */
  --color-text: #0f172a;
  --color-text-muted: #6b7280;
  --color-text-soft: #9ca3af;

  /* Compatibilità con variabili esistenti */
  --bg: var(--color-bg);
  --bg-soft: var(--color-bg-soft);
  --bg-card: var(--color-bg-card);
  --border-subtle: var(--color-border-subtle);
  --border-strong: var(--color-border-strong);
  --text-main: var(--color-text);
  --text-muted: var(--color-text-muted);
  --text-soft: var(--color-text-soft);
  --accent: var(--color-primary);
  --accent-strong: var(--color-primary-hover);
  --accent-soft: var(--color-primary-light);

  /* Sidebar (compatibilità) */
  --sidebar-bg: #020617;
  --sidebar-border: #111827;
  --sidebar-text: #e5e7eb;
  --sidebar-text-muted: #9ca3af;
  --sidebar-active-bg: #111827;

  /* ============================================
     🔤 TIPOGRAFIA
     ============================================ */

  --font-family-base: system-ui, -apple-system, BlinkMacSystemFont,
    "SF Pro Text", "Segoe UI", "Inter", "Roboto", "Helvetica Neue", Arial,
    sans-serif;
  --font-family-mono: "SF Mono", "Monaco", "Inconsolata", "Fira Code",
    "Fira Mono", "Droid Sans Mono", "Source Code Pro", monospace;

  --font-size-xs: 0.75rem; /* 12px */
  --font-size-sm: 0.875rem; /* 14px */
  --font-size-base: 1rem; /* 16px */
  --font-size-lg: 1.125rem; /* 18px */
  --font-size-xl: 1.25rem; /* 20px */
  --font-size-2xl: 1.5rem; /* 24px */
  --font-size-3xl: 1.875rem; /* 30px */
  --font-size-4xl: 2.25rem; /* 36px */

  --font-weight-normal: 400;
  --font-weight-medium: 500;
  --font-weight-semibold: 600;
  --font-weight-bold: 700;

  --line-height-tight: 1.25;
  --line-height-normal: 1.5;
  --line-height-relaxed: 1.75;

  /* ============================================
     📐 SPACING SCALE
     ============================================ */

  --space-1: 0.25rem; /* 4px */
  --space-2: 0.5rem; /* 8px */
  --space-3: 0.75rem; /* 12px */
  --space-4: 1rem; /* 16px */
  --space-5: 1.25rem; /* 20px */
  --space-6: 1.5rem; /* 24px */
  --space-8: 2rem; /* 32px */
  --space-10: 2.5rem; /* 40px */
  --space-12: 3rem; /* 48px */
  --space-16: 4rem; /* 64px */
  --space-20: 5rem; /* 80px */

  /* ============================================
     🔲 BORDER & RADIUS
     ============================================ */

  --radius-sm: 0.375rem; /* 6px */
  --radius-md: 0.625rem; /* 10px */
  --radius-lg: 0.75rem; /* 12px */
  --radius-xl: 1rem; /* 16px */
  --radius-2xl: 1.25rem; /* 20px */
  --radius-full: 9999px;

  --radius-card: 1rem; /* 16px */
  --radius-input: 0.75rem; /* 12px */
  --radius-btn: 0.75rem; /* 12px */

  --border-width: 1px;
  --border-width-thick: 2px;

  /* Compatibilità con variabili esistenti */
  --radius-md: var(--radius-md);
  --radius-lg: var(--radius-lg);
  --radius-xl: var(--radius-xl);

  /* ============================================
     🌫 SHADOWS
     ============================================ */

  --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
  --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);

  /* Compatibilità con variabili esistenti */
  --shadow-soft: 0 10px 30px rgba(15, 23, 42, 0.1);
  --shadow-medium: 0 18px 45px rgba(15, 23, 42, 0.16);

  /* ============================================
     🧭 Z-INDEX SYSTEM
     ============================================ */

  --z-base: 0;
  --z-dropdown: 1000;
  --z-sticky: 1020;
  --z-fixed: 1030;
  --z-overlay: 1040;
  --z-modal: 1050;
  --z-popover: 1060;
  --z-tooltip: 1070;

  /* ============================================
     ⚡ TRANSITIONS
     ============================================ */

  --transition-fast: 0.15s ease;
  --transition-base: 0.2s ease;
  --transition-medium: 0.25s ease;
  --transition-slow: 0.3s ease;

  /* Compatibilità con variabili esistenti */
  --transition-fast: var(--transition-fast);
  --transition-medium: var(--transition-medium);
}

/* ============================================
   STILI GLOBALI BASE
   ============================================ */

/* Body */
body {
  font-family: var(--font-family-base);
  font-size: var(--font-size-base);
  line-height: var(--line-height-normal);
  color: var(--color-text);
  background: var(--color-bg, #f8fafc);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

/* Headings */
h1,
h2,
h3,
h4,
h5,
h6 {
  font-weight: var(--font-weight-semibold);
  line-height: var(--line-height-tight);
  color: var(--color-text);
  margin: 0;
}

h1 {
  font-size: var(--font-size-4xl);
  font-weight: var(--font-weight-bold);
}

h2 {
  font-size: var(--font-size-3xl);
}

h3 {
  font-size: var(--font-size-2xl);
}

h4 {
  font-size: var(--font-size-xl);
}

h5 {
  font-size: var(--font-size-lg);
}

h6 {
  font-size: var(--font-size-base);
  font-weight: var(--font-weight-medium);
}

/* Paragrafi */
p {
  margin: 0;
  line-height: var(--line-height-relaxed);
  color: var(--color-text);
}

/* Link */
a {
  color: var(--color-primary);
  text-decoration: none;
  transition: color var(--transition-fast);
}

a:hover {
  color: var(--color-primary-hover);
  text-decoration: underline;
}

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

/* Liste */
ul,
ol {
  margin: 0;
  padding: 0;
}

li {
  margin: 0;
}

/* Code */
code,
kbd,
samp,
pre {
  font-family: var(--font-family-mono);
  font-size: 0.9em;
}

code {
  background: var(--color-bg-soft);
  padding: 0.125rem 0.25rem;
  border-radius: var(--radius-sm);
  color: var(--color-danger);
}

pre {
  background: var(--color-bg-soft);
  padding: var(--space-4);
  border-radius: var(--radius-md);
  overflow-x: auto;
  line-height: var(--line-height-relaxed);
}

/* Blockquote */
blockquote {
  margin: 0;
  padding-left: var(--space-4);
  border-left: var(--border-width-thick) solid var(--color-border);
  color: var(--color-text-muted);
  font-style: italic;
}

/* Horizontal rule */
hr {
  border: none;
  border-top: var(--border-width) solid var(--color-border-subtle);
  margin: var(--space-6) 0;
}

/* ============================================
   FORM ELEMENTS BASE
   ============================================ */

/* Input, textarea, select base */
input,
textarea,
select {
  font-family: var(--font-family-base);
  font-size: var(--font-size-base);
  line-height: var(--line-height-normal);
  color: var(--color-text);
  background: var(--color-bg-card);
  border: var(--border-width) solid var(--color-border);
  border-radius: var(--radius-md);
  padding: var(--space-2) var(--space-3);
  transition: border-color var(--transition-fast),
    box-shadow var(--transition-fast);
}

input:focus,
textarea:focus,
select:focus {
  outline: none;
  border-color: var(--color-primary);
  box-shadow: 0 0 0 3px var(--color-primary-light);
}

input:disabled,
textarea:disabled,
select:disabled {
  background: var(--color-bg-soft);
  color: var(--color-text-muted);
  cursor: not-allowed;
  opacity: 0.6;
}

/* Button base */
button {
  font-family: var(--font-family-base);
  font-size: var(--font-size-base);
  line-height: var(--line-height-normal);
  cursor: pointer;
  transition: all var(--transition-fast);
}

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

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

/* ============================================
   ACCESSIBILITÀ
   ============================================ */

/* Focus visible (solo quando navigazione da tastiera) */
*:focus-visible {
  outline: 2px solid var(--color-primary);
  outline-offset: 2px;
  border-radius: var(--radius-sm);
}

/* Skip link per screen reader */
.skip-link {
  position: absolute;
  top: -40px;
  left: 0;
  background: var(--color-primary);
  color: white;
  padding: var(--space-2) var(--space-4);
  text-decoration: none;
  z-index: var(--z-tooltip);
  border-radius: 0 0 var(--radius-md) 0;
}

.skip-link:focus {
  top: 0;
}

/* Reduced motion */
@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
}

/* High contrast mode support */
@media (prefers-contrast: high) {
  :root {
    --color-border: #000000;
    --color-border-subtle: #333333;
    --color-text-muted: #000000;
  }
}

/* ============================================
   SCROLLBAR STYLING
   ============================================ */

/* Firefox */
body,
.sidebar {
  scrollbar-width: thin;
  scrollbar-color: var(--color-text-soft) var(--color-bg-soft);
}

/* Webkit (Chrome, Safari, Edge) */
body::-webkit-scrollbar,
.sidebar::-webkit-scrollbar {
  width: 8px;
  height: 8px;
}

body::-webkit-scrollbar-track,
.sidebar::-webkit-scrollbar-track {
  background: transparent;
}

body::-webkit-scrollbar-thumb,
.sidebar::-webkit-scrollbar-thumb {
  background-color: var(--color-text-soft);
  border-radius: var(--radius-full);
}

body::-webkit-scrollbar-thumb:hover,
.sidebar::-webkit-scrollbar-thumb:hover {
  background-color: var(--color-text-muted);
}

/* ============================================
   UTILITY CLASSES BASE
   ============================================ */

/* Screen reader only */
.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;
}

/* Clearfix */
.clearfix::after {
  content: "";
  display: table;
  clear: both;
}