/* ============================================================
   NIEUWEAUTOKOSTEN.NL — Gedeelde Stijlen
   Design: Minimalistisch, Apple-achtig
   ============================================================ */

/* ---------- CSS Custom Properties (Design Tokens) ---------- */
:root {
  --color-bg:           #f5f5f7;
  --color-surface:      #ffffff;
  --color-text:         #1d1d1f;
  --color-text-secondary: #6e6e73;
  --color-border:       #e5e5ea;
  --color-optie1:       #007aff;
  --color-optie1-light: #e8f2ff;
  --color-optie2:       #34c759;
  --color-optie2-light: #eafbef;
  --color-primary:      #007aff;
  --color-primary-hover:#0060d0;
  --color-error:        #ff3b30;
  --color-success:      #34c759;
  --radius:             12px;
  --radius-sm:          8px;
  --shadow:             0 2px 12px rgba(0, 0, 0, 0.06);
  --shadow-lg:          0 4px 24px rgba(0, 0, 0, 0.08);
  --transition:         0.2s ease;
  --font-sans: -apple-system, BlinkMacSystemFont, 'SF Pro Display',
               'Segoe UI', Roboto, Helvetica, Arial, sans-serif;
}

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

html {
  font-size: 16px;
  scroll-behavior: smooth;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

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

/* ---------- Layout ---------- */
.container { width: 100%; max-width: 960px; margin: 0 auto; padding: 0 20px; }

/* ---------- Header & Navigatie ---------- */
.header {
  background: var(--color-surface);
  border-bottom: 1px solid var(--color-border);
  padding: 28px 0 20px;
  text-align: center;
}
.header-content .logo { font-size: 1.75rem; font-weight: 700; letter-spacing: -0.02em; }
.header-content .subtitle { margin-top: 4px; font-size: 1rem; color: var(--color-text-secondary); font-weight: 400; }

.logo-link { text-decoration: none; color: inherit; }
.logo-link:hover { opacity: 0.8; }

.main-nav {
  display: flex; gap: 6px; margin-top: 16px;
  justify-content: center; flex-wrap: wrap;
}
.nav-link {
  padding: 8px 18px; border-radius: var(--radius-sm);
  font-size: 0.9rem; font-weight: 500; text-decoration: none;
  color: var(--color-text-secondary);
  transition: all var(--transition);
}
.nav-link:hover { color: var(--color-text); background: var(--color-bg); }
.nav-link.active { color: var(--color-primary); background: var(--color-optie1-light); font-weight: 600; }

/* ---------- Cards ---------- */
.card {
  background: var(--color-surface);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 32px;
  margin-top: 24px;
}
.card-header { display: flex; align-items: center; gap: 12px; margin-bottom: 8px; }
.card-header h2 { font-size: 1.25rem; font-weight: 600; letter-spacing: -0.01em; }
.card-description { color: var(--color-text-secondary); font-size: 0.9rem; margin-bottom: 24px; line-height: 1.5; }

.step-badge {
  display: inline-flex; align-items: center; justify-content: center;
  width: 32px; height: 32px; border-radius: 50%;
  background: var(--color-text); color: #fff;
  font-size: 0.85rem; font-weight: 600; flex-shrink: 0;
}
.result-badge { background: var(--color-success); }

/* ---------- Buttons ---------- */
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 8px;
  padding: 12px 24px; border: none; border-radius: var(--radius-sm);
  font-size: 0.95rem; font-weight: 600; cursor: pointer;
  transition: all var(--transition); font-family: var(--font-sans); white-space: nowrap;
}
.btn-primary { background: var(--color-primary); color: #fff; }
.btn-primary:hover { background: var(--color-primary-hover); transform: translateY(-1px); box-shadow: 0 4px 12px rgba(0, 122, 255, 0.3); }
.btn-primary:active { transform: translateY(0); }
.btn-primary:disabled { opacity: 0.6; cursor: not-allowed; transform: none; box-shadow: none; }
.btn-sm { padding: 8px 16px; font-size: 0.85rem; }

.btn-loader {
  display: inline-block; width: 14px; height: 14px;
  border: 2px solid rgba(255,255,255,0.3); border-top-color: #fff;
  border-radius: 50%; animation: spin 0.6s linear infinite;
}
@keyframes spin { to { transform: rotate(360deg); } }

/* ---------- Form Elements ---------- */
.form-grid { display: grid; gap: 20px; }
.form-grid.cols-2 { grid-template-columns: 1fr 1fr; }
.form-grid.cols-3 { grid-template-columns: repeat(3, 1fr); }

.form-group { display: flex; flex-direction: column; gap: 6px; }
.form-group label { font-size: 0.85rem; font-weight: 500; color: var(--color-text-secondary); }

.form-group input[type="number"],
.form-group select {
  padding: 10px 14px; border: 1.5px solid var(--color-border); border-radius: var(--radius-sm);
  font-size: 0.95rem; font-family: var(--font-sans); color: var(--color-text);
  background: var(--color-surface);
  transition: border-color var(--transition), box-shadow var(--transition);
  -moz-appearance: textfield;
}
.form-group input[type="number"]::-webkit-outer-spin-button,
.form-group input[type="number"]::-webkit-inner-spin-button { -webkit-appearance: none; margin: 0; }
.form-group input:focus,
.form-group select:focus { outline: none; border-color: var(--color-primary); box-shadow: 0 0 0 3px rgba(0, 122, 255, 0.12); }

.form-stack { display: flex; flex-direction: column; gap: 16px; }

/* Input met unit prefix/suffix */
.input-with-unit {
  display: flex; align-items: center;
  border: 1.5px solid var(--color-border); border-radius: var(--radius-sm);
  overflow: hidden; transition: border-color var(--transition), box-shadow var(--transition);
  background: var(--color-surface);
}
.input-with-unit:focus-within { border-color: var(--color-primary); box-shadow: 0 0 0 3px rgba(0, 122, 255, 0.12); }
.input-with-unit .unit-prefix { padding: 10px 0 10px 14px; font-size: 0.95rem; color: var(--color-text-secondary); font-weight: 500; }
.input-with-unit .unit-suffix { padding: 10px 14px 10px 4px; font-size: 0.8rem; color: var(--color-text-secondary); white-space: nowrap; }
.input-with-unit input {
  border: none; padding: 10px 8px; font-size: 0.95rem; font-family: var(--font-sans);
  color: var(--color-text); width: 100%; outline: none; background: transparent; -moz-appearance: textfield;
}
.input-with-unit input::-webkit-outer-spin-button,
.input-with-unit input::-webkit-inner-spin-button { -webkit-appearance: none; }

/* ---------- Slider ---------- */
.slider-group { display: flex; flex-direction: column; gap: 12px; }
.slider-header { display: flex; justify-content: space-between; align-items: center; flex-wrap: wrap; gap: 8px; }
.slider-header label { font-size: 0.95rem; font-weight: 500; color: var(--color-text); }
.slider-value-display { display: flex; align-items: center; gap: 6px; background: var(--color-bg); border-radius: var(--radius-sm); padding: 4px 12px; }
.slider-value-display input {
  border: none; background: transparent; font-size: 1rem; font-weight: 600;
  color: var(--color-text); width: 70px; text-align: right; outline: none;
  font-family: var(--font-sans); -moz-appearance: textfield;
}
.slider-value-display input::-webkit-outer-spin-button,
.slider-value-display input::-webkit-inner-spin-button { -webkit-appearance: none; }
.slider-value-display .unit { font-size: 0.8rem; color: var(--color-text-secondary); }

input[type="range"] { -webkit-appearance: none; appearance: none; width: 100%; height: 6px; border-radius: 3px; background: var(--color-border); outline: none; }
input[type="range"]::-webkit-slider-thumb { -webkit-appearance: none; width: 24px; height: 24px; border-radius: 50%; background: var(--color-primary); cursor: pointer; box-shadow: 0 2px 6px rgba(0, 122, 255, 0.3); transition: transform var(--transition); }
input[type="range"]::-webkit-slider-thumb:hover { transform: scale(1.15); }
input[type="range"]::-moz-range-thumb { width: 24px; height: 24px; border-radius: 50%; background: var(--color-primary); cursor: pointer; border: none; box-shadow: 0 2px 6px rgba(0, 122, 255, 0.3); }
.slider-labels { display: flex; justify-content: space-between; font-size: 0.75rem; color: var(--color-text-secondary); }

/* ---------- Formule / Info box ---------- */
.formula-box { margin-top: 24px; padding: 16px 20px; background: var(--color-bg); border-radius: var(--radius-sm); border-left: 3px solid var(--color-primary); }
.formula-label { display: block; font-size: 0.75rem; font-weight: 600; color: var(--color-text-secondary); text-transform: uppercase; letter-spacing: 0.05em; margin-bottom: 6px; }
.formula-box code { font-size: 0.85rem; color: var(--color-text); word-break: break-word; }

/* ---------- Result styling (gedeeld) ---------- */
.result-label { display: block; font-size: 0.85rem; font-weight: 500; color: var(--color-text-secondary); margin-bottom: 8px; }
.result-amount { display: block; font-size: 2rem; font-weight: 700; letter-spacing: -0.02em; }

/* ---------- Footer ---------- */
.footer { margin-top: 48px; padding: 24px 0; text-align: center; color: var(--color-text-secondary); font-size: 0.8rem; border-top: 1px solid var(--color-border); }
.footer a { color: var(--color-primary); text-decoration: none; }
.footer a:hover { text-decoration: underline; }

/* ---------- Utilities ---------- */
.hidden { display: none !important; }

/* ---------- Responsive (Tablet) ---------- */
@media (max-width: 768px) {
  .header { padding: 20px 0 16px; }
  .header-content .logo { font-size: 1.35rem; }
  .main-nav { gap: 4px; }
  .nav-link { padding: 6px 12px; font-size: 0.8rem; }
  .card { padding: 24px; }
  .form-grid.cols-2,
  .form-grid.cols-3 { grid-template-columns: 1fr; }
}

/* ---------- Gebruiksteller badge ---------- */
.usage-counter {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 6px;
  margin: 12px 0 4px;
  font-size: 0.82rem;
  color: var(--color-text-secondary);
}

.usage-counter-icon {
  font-size: 0.9rem;
  opacity: 0.7;
}

.usage-counter strong {
  color: var(--color-primary);
  font-weight: 600;
}

/* ---------- Responsive (Mobiel) ---------- */
@media (max-width: 480px) {
  .container { padding: 0 16px; }
  .card { padding: 20px; border-radius: var(--radius-sm); }
  .header-content .logo { font-size: 1.2rem; }
  .result-amount { font-size: 1.6rem; }
}