/* ============================================================
   design-system.css — Calculadora de Nómina España
   Sistema de diseño profesional global. Carga ANTES del CSS
   existente. Las variables se exponen en :root y la tipografía
   se aplica con prioridad alta.
   ============================================================ */

/* ===== Tipografía Google Fonts ===== */
@import url('https://fonts.googleapis.com/css2?family=Plus+Jakarta+Sans:wght@600;700&family=DM+Sans:wght@400;500&display=swap');

/* ===== Variables globales ===== */
:root {
  /* Colores principales */
  --color-primary: #1E40AF;
  --color-primary-dark: #1E3A8A;
  --color-primary-light: #EFF6FF;
  --color-accent: #0EA5E9;

  /* Texto */
  --color-text-primary: #0F172A;
  --color-text-secondary: #475569;
  --color-text-muted: #94A3B8;

  /* Fondos */
  --color-bg: #FFFFFF;
  --color-bg-secondary: #F8FAFC;
  --color-bg-tertiary: #F1F5F9;

  /* Bordes */
  --color-border: #E2E8F0;
  --color-border-strong: #CBD5E1;

  /* Estados */
  --color-success: #059669;
  --color-success-light: #ECFDF5;
  --color-warning: #D97706;
  --color-warning-light: #FFFBEB;
  --color-danger: #DC2626;
  --color-danger-light: #FEF2F2;

  /* Sombras */
  --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.08);
  --shadow-md: 0 4px 16px rgba(0, 0, 0, 0.08);
  --shadow-lg: 0 8px 32px rgba(0, 0, 0, 0.10);

  /* Radios */
  --radius-sm: 6px;
  --radius-md: 10px;
  --radius-lg: 16px;
  --radius-xl: 24px;

  /* Espacios */
  --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-12: 3rem;

  /* Tipografía */
  --font-display: 'Plus Jakarta Sans', system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  --font-body: 'DM Sans', system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
}

/* ===== Reset y base tipográfica (con prioridad para sobrescribir inline styles) ===== */
html {
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}

body {
  font-family: var(--font-body) !important;
  font-size: 1rem;
  line-height: 1.6;
  color: var(--color-text-primary);
  background: var(--color-bg);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

h1, h2, h3 {
  font-family: var(--font-display) !important;
  font-weight: 700;
  line-height: 1.2;
  color: var(--color-text-primary);
  letter-spacing: -0.02em;
}

h4, h5, h6 {
  font-family: var(--font-display) !important;
  font-weight: 600;
  line-height: 1.3;
  color: var(--color-text-primary);
}

h1 { font-size: 2.25rem; }
h2 { font-size: 1.75rem; }
h3 { font-size: 1.375rem; }
h4 { font-size: 1.125rem; }
h5 { font-size: 1rem; }
h6 { font-size: 0.875rem; }

p, li, td, th, label, input, select, textarea, button {
  font-family: var(--font-body) !important;
}

p, li, td {
  font-size: 1rem;
  line-height: 1.6;
}

small, .small {
  font-size: 0.875rem;
}

a {
  color: var(--color-primary);
  text-decoration: none;
  transition: color 0.2s ease;
}

a:hover {
  color: var(--color-primary-dark);
}

/* ===== Utilidades de layout ===== */
.ds-container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 var(--space-6);
}

.ds-container-narrow {
  max-width: 720px;
  margin: 0 auto;
  padding: 0 var(--space-6);
}

/* ===== Botones ===== */
.btn,
.btn-primary,
.btn-secondary {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-2);
  padding: 0.625rem 1.25rem;
  font-family: var(--font-body);
  font-size: 0.9375rem;
  font-weight: 500;
  line-height: 1.4;
  border-radius: var(--radius-md);
  border: 1.5px solid transparent;
  cursor: pointer;
  text-decoration: none;
  transition: all 0.2s ease;
  white-space: nowrap;
}

.btn-primary {
  background: var(--color-primary);
  color: #ffffff;
  border-color: var(--color-primary);
}

.btn-primary:hover {
  background: var(--color-primary-dark);
  border-color: var(--color-primary-dark);
  color: #ffffff;
  transform: translateY(-1px);
  box-shadow: var(--shadow-md);
}

.btn-secondary {
  background: transparent;
  color: var(--color-text-primary);
  border-color: var(--color-border-strong);
}

.btn-secondary:hover {
  background: var(--color-bg-secondary);
  border-color: var(--color-primary);
  color: var(--color-primary);
}

/* ===== Cards de blog ===== */
.ds-card,
.ds-blog-card {
  display: block;
  background: var(--color-bg);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: var(--space-6);
  text-decoration: none;
  color: inherit;
  transition: transform 0.2s ease, box-shadow 0.2s ease, border-color 0.2s ease;
}

.ds-card:hover,
.ds-blog-card:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
  border-color: var(--color-border-strong);
}

.ds-tag {
  display: inline-block;
  background: var(--color-primary-light);
  color: var(--color-primary);
  font-family: var(--font-body);
  font-size: 0.75rem;
  font-weight: 500;
  border-radius: var(--radius-sm);
  padding: 0.25rem 0.625rem;
  margin-bottom: var(--space-3);
}

.ds-card-title {
  font-family: var(--font-display);
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--color-text-primary);
  margin: 0 0 var(--space-3);
  line-height: 1.3;
}

.ds-card-desc {
  font-family: var(--font-body);
  color: var(--color-text-secondary);
  font-size: 0.9375rem;
  line-height: 1.6;
  margin: 0 0 var(--space-4);
}

.ds-read-more {
  color: var(--color-primary);
  font-weight: 500;
  font-size: 0.9375rem;
  text-decoration: none;
}

.ds-read-more::after {
  content: ' →';
  transition: transform 0.2s ease;
}

.ds-card:hover .ds-read-more::after {
  transform: translateX(2px);
}

/* ===== Calculadora — inputs ===== */
.ds-input,
.ds-select,
.ds-textarea {
  width: 100%;
  padding: 0.75rem 1rem;
  border: 1.5px solid var(--color-border);
  border-radius: var(--radius-md);
  font-family: var(--font-body);
  font-size: 1rem;
  color: var(--color-text-primary);
  background: var(--color-bg);
  transition: border-color 0.2s ease, box-shadow 0.2s ease;
  outline: none;
}

.ds-input:focus,
.ds-select:focus,
.ds-textarea:focus {
  border-color: var(--color-primary);
  box-shadow: 0 0 0 3px rgba(30, 64, 175, 0.1);
}

.ds-label {
  display: block;
  font-family: var(--font-body);
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--color-text-secondary);
  margin-bottom: 0.375rem;
}

.ds-result-highlight {
  background: var(--color-primary-light);
  border-left: 4px solid var(--color-primary);
  padding: 1.25rem 1.5rem;
  border-radius: var(--radius-md);
  margin: var(--space-4) 0;
}

/* ===== Tablas ===== */
.ds-table-wrap {
  overflow-x: auto;
  margin: var(--space-6) 0;
}

.ds-table {
  width: 100%;
  border-collapse: collapse;
  background: var(--color-bg);
  border-radius: var(--radius-md);
  overflow: hidden;
  border: 1px solid var(--color-border);
}

.ds-table th {
  background: var(--color-bg-secondary);
  font-family: var(--font-body);
  font-weight: 600;
  font-size: 0.8125rem;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  color: var(--color-text-secondary);
  padding: 0.875rem 1rem;
  text-align: left;
  border-bottom: 1px solid var(--color-border);
}

.ds-table td {
  padding: 0.875rem 1rem;
  border-bottom: 1px solid var(--color-border);
  color: var(--color-text-primary);
  font-size: 0.9375rem;
}

.ds-table tr:nth-child(even) td {
  background: var(--color-bg-secondary);
}

.ds-table tr:last-child td {
  border-bottom: none;
}

.ds-value-positive { color: var(--color-primary); font-weight: 500; }
.ds-value-negative { color: var(--color-danger); font-weight: 500; }
.ds-value-total {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 1.25rem;
  color: var(--color-primary);
}

/* ===== Artículos de blog (single) ===== */
.ds-article-content {
  max-width: 720px;
  margin: 0 auto;
}

.ds-article-content p {
  line-height: 1.75;
  color: var(--color-text-secondary);
  margin-bottom: var(--space-4);
}

.ds-article-content h2 {
  border-bottom: 1px solid var(--color-border);
  padding-bottom: var(--space-2);
  margin-top: var(--space-8);
  margin-bottom: var(--space-4);
}

.ds-article-content blockquote {
  border-left: 4px solid var(--color-primary);
  padding-left: var(--space-4);
  margin: var(--space-6) 0;
  color: var(--color-text-secondary);
  font-style: italic;
}

/* ===== Header / Navbar mejorado (utilidad) ===== */
.ds-navbar {
  background: var(--color-bg);
  border-bottom: 1px solid var(--color-border);
  box-shadow: var(--shadow-sm);
  padding: 0.875rem 0;
  position: sticky;
  top: 0;
  z-index: 100;
}

.ds-navbar-inner {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 var(--space-6);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-6);
}

.ds-navbar a.ds-logo {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 1.125rem;
  color: var(--color-primary);
  text-decoration: none;
}

.ds-nav-links {
  display: flex;
  gap: var(--space-6);
  align-items: center;
  list-style: none;
  margin: 0;
  padding: 0;
}

.ds-nav-links a {
  font-family: var(--font-body);
  font-weight: 500;
  font-size: 0.9375rem;
  color: var(--color-text-secondary);
  text-decoration: none;
  transition: color 0.2s ease;
}

.ds-nav-links a:hover,
.ds-nav-links a[aria-current="page"] {
  color: var(--color-primary);
}

/* ===== Footer mejorado (utilidad) ===== */
.ds-footer {
  background: var(--color-bg-secondary);
  border-top: 1px solid var(--color-border);
  padding: var(--space-12) var(--space-6);
  color: var(--color-text-muted);
  font-family: var(--font-body);
}

.ds-footer a {
  color: var(--color-text-secondary);
  font-size: 0.9375rem;
}

.ds-footer a:hover {
  color: var(--color-primary);
}

.ds-footer-copyright {
  color: var(--color-text-muted);
  font-size: 0.875rem;
}

/* ===== Hero (utilidad para index.html) ===== */
.ds-hero {
  background: linear-gradient(180deg, #EFF6FF 0%, #FFFFFF 100%);
  padding: var(--space-12) var(--space-6);
  text-align: center;
}

.ds-hero h1 {
  font-size: 3rem;
  margin-bottom: var(--space-4);
  letter-spacing: -0.03em;
}

.ds-hero p.ds-subtitle {
  font-size: 1.125rem;
  color: var(--color-text-secondary);
  max-width: 640px;
  margin: 0 auto var(--space-6);
}

/* ===== Responsive ===== */
@media (max-width: 768px) {
  h1 { font-size: 1.875rem; }
  h2 { font-size: 1.5rem; }
  h3 { font-size: 1.25rem; }

  .ds-hero h1 { font-size: 2.25rem; }
  .ds-hero p.ds-subtitle { font-size: 1rem; }

  .ds-nav-links {
    display: none;
  }

  .ds-card,
  .ds-blog-card {
    padding: var(--space-5);
  }
}

@media (min-width: 1280px) {
  .ds-container { padding: 0 var(--space-8); }
}

/* ===== Print ===== */
@media print {
  .ds-navbar, .ds-footer { display: none; }
}