/* ============================================================
   Operational Excellence — IBM Carbon-geïnspireerde stylesheet
   Strak, zakelijk, scherpe hoeken. Zie /style/IBM-carbon-reference.md
   ============================================================ */

/* ── Design tokens (Carbon White theme) ── */
:root {
  --background:      #ffffff;
  --layer-01:        #f4f4f4;
  --layer-02:        #ffffff;
  --text-primary:    #161616;
  --text-secondary:  #525252;
  --text-helper:     #6f6f6f;
  --link:            #0f62fe;
  --link-hover:      #0353e9;
  --active:          #002d9c;
  --border-subtle:   #e0e0e0;
  --border-strong:   #8d8d8d;
  --gray-90:         #262626;
  --gray-100:        #161616;
  --interactive:     #0f62fe;
  --success:         #24a148;
  --text-on-color:   #ffffff;
  --maxw:            1312px;
}

/* ── Reset ── */
*, *::before, *::after { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; scroll-behavior: smooth; }
body {
  margin: 0;
  font-family: 'IBM Plex Sans', system-ui, -apple-system, Segoe UI, Roboto, sans-serif;
  color: var(--text-primary);
  background: var(--background);
  line-height: 1.5;
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
}
img { max-width: 100%; display: block; }
a { color: var(--link); text-decoration: underline; text-underline-offset: 2px; }
a:hover { color: var(--link-hover); }
h1, h2, h3, h4 { margin: 0 0 0.5em; font-weight: 400; line-height: 1.15; letter-spacing: 0; }
p { margin: 0 0 1rem; }
/* Carbon: scherpe hoeken overal */
button, input, textarea, select, .btn, .card, .tag { border-radius: 0; }

/* ── Layout helpers ── */
.container { max-width: var(--maxw); margin: 0 auto; padding: 0 1.5rem; }
.section { padding: 4.5rem 0; }
.section--sm { padding: 3rem 0; }
.section--layer { background: var(--layer-01); }
.section--dark { background: var(--gray-100); color: var(--text-on-color); }
.section--blue { background: var(--interactive); color: var(--text-on-color); }
.section--dark h1, .section--dark h2, .section--dark h3,
.section--blue h1, .section--blue h2, .section--blue h3 { color: var(--text-on-color); }

/* Simple 12-col grid */
.grid { display: grid; grid-template-columns: repeat(12, 1fr); gap: 2rem; }
.col-12 { grid-column: span 12; }
.col-8  { grid-column: span 8; }
.col-7  { grid-column: span 7; }
.col-6  { grid-column: span 6; }
.col-5  { grid-column: span 5; }
.col-4  { grid-column: span 4; }
.col-3  { grid-column: span 3; }
@media (max-width: 900px) {
  .grid { gap: 1.5rem; }
  .col-8, .col-7, .col-6, .col-5, .col-4, .col-3 { grid-column: span 12; }
}

.vcenter { align-items: center; }
.stretch { align-items: stretch; }

/* ── Typography utilities ── */
.eyebrow {
  font-size: 0.75rem; font-weight: 600; text-transform: uppercase;
  letter-spacing: 0.16em; color: var(--link); margin: 0 0 1rem;
}
.display { font-size: clamp(2.25rem, 5vw, 3.375rem); font-weight: 300; line-height: 1.1; letter-spacing: -0.01em; }
.h2 { font-size: clamp(1.75rem, 3.2vw, 2.625rem); font-weight: 300; }
.h3 { font-size: 1.5rem; font-weight: 400; }
.h4 { font-size: 1.25rem; font-weight: 600; }
.lead { font-size: 1.25rem; color: var(--text-secondary); font-weight: 300; }
.muted { color: var(--text-secondary); }
.small { font-size: 0.875rem; }
.mono { font-family: 'IBM Plex Mono', monospace; }
.mt-0 { margin-top: 0; } .mb-0 { margin-bottom: 0; }
.mt-1 { margin-top: 0.5rem; } .mt-2 { margin-top: 1rem; } .mt-3 { margin-top: 1.5rem; } .mt-4 { margin-top: 2rem; }
.mb-2 { margin-bottom: 1rem; } .mb-3 { margin-bottom: 1.5rem; } .mb-4 { margin-bottom: 2rem; }

/* ── Buttons (Carbon: rechthoekig, pijl rechts) ── */
.btn {
  display: inline-flex; align-items: center; justify-content: space-between; gap: 2.5rem;
  font-family: inherit; font-size: 1rem; font-weight: 400; line-height: 1.2;
  padding: 0.875rem 1rem; min-height: 48px;
  border: 1px solid transparent; cursor: pointer; text-decoration: none;
  transition: background 0.11s, border-color 0.11s, color 0.11s;
  max-width: 20rem;
}
.btn::after { content: "→"; font-size: 1.1rem; line-height: 1; }
.btn--noicon { gap: 0; }
.btn--noicon::after { content: ""; }
.btn--primary { background: var(--interactive); color: #fff; border-color: var(--interactive); }
.btn--primary:hover { background: var(--link-hover); color: #fff; }
.btn--primary:active { background: var(--active); }
.btn--secondary { background: var(--gray-90); color: #fff; border-color: var(--gray-90); }
.btn--secondary:hover { background: #4c4c4c; color: #fff; }
.btn--tertiary { background: transparent; color: var(--link); border-color: var(--link); }
.btn--tertiary:hover { background: var(--link); color: #fff; }
.btn--ghost { background: transparent; color: var(--link); border-color: transparent; padding-left: 0; }
.btn--ghost:hover { color: var(--link-hover); }
.btn--on-dark.btn--tertiary { color: #fff; border-color: #fff; }
.btn--on-dark.btn--tertiary:hover { background: #fff; color: var(--gray-100); }
.btn--block { display: flex; max-width: none; width: 100%; }

/* ── Header ── */
.site-header { position: sticky; top: 0; z-index: 100; background: #fff; border-bottom: 1px solid var(--border-subtle); }
.top-bar { background: var(--gray-100); color: rgba(255,255,255,0.85); font-size: 0.8125rem; }
.top-bar .container { display: flex; justify-content: space-between; align-items: center; gap: 1rem; height: 36px; flex-wrap: wrap; }
.top-bar a { color: rgba(255,255,255,0.85); text-decoration: none; }
.top-bar a:hover { color: #fff; }
.top-bar .usps { display: flex; gap: 1.5rem; }
@media (max-width: 820px) { .top-bar .usps { display: none; } }

.navbar { display: flex; align-items: center; justify-content: space-between; height: 64px; }
.navbar .brand { display: flex; align-items: center; gap: 0.6rem; text-decoration: none; color: var(--text-primary); font-weight: 600; font-size: 1.0625rem; letter-spacing: -0.01em; }
.navbar .brand .mark { width: 28px; height: 28px; background: var(--interactive); display: inline-block; }
.navbar .brand b { font-weight: 600; }
.navbar .brand span { font-weight: 300; color: var(--text-secondary); }
.nav-links { display: flex; align-items: center; gap: 0; list-style: none; margin: 0; padding: 0; height: 100%; }
.nav-links a { color: var(--text-primary); text-decoration: none; font-size: 0.9375rem; padding: 0 1rem; height: 64px; display: flex; align-items: center; border-bottom: 2px solid transparent; }
.nav-links a:hover { border-bottom-color: var(--interactive); }
.nav-links a.is-active { border-bottom-color: var(--interactive); font-weight: 600; }
.nav-cta { margin-left: 1rem; }
.nav-toggle { display: none; background: none; border: none; cursor: pointer; padding: 0.5rem; }
.nav-toggle span { display: block; width: 22px; height: 2px; background: var(--text-primary); margin: 4px 0; }
@media (max-width: 900px) {
  .nav-toggle { display: block; }
  .nav-links { position: absolute; top: 100px; left: 0; right: 0; flex-direction: column; background: #fff; border-bottom: 1px solid var(--border-subtle); height: auto; display: none; }
  .nav-links.is-open { display: flex; }
  .nav-links a { height: auto; padding: 0.9rem 1.5rem; width: 100%; border-bottom: 1px solid var(--border-subtle); }
  .nav-cta { margin: 1rem 1.5rem; }
}

/* ── Hero ── */
.hero { background: var(--layer-01); padding: 4.5rem 0 5rem; border-bottom: 1px solid var(--border-subtle); }
.hero .display { margin-bottom: 1.5rem; }
.hero .lead { max-width: 36rem; }
.hero-actions { display: flex; flex-wrap: wrap; gap: 1px; margin-top: 2rem; }
.hero-art { background: var(--gray-100); aspect-ratio: 4/3; display: flex; align-items: center; justify-content: center; overflow: hidden; }
.hero-art img { width: 100%; height: 100%; object-fit: cover; }

/* ── Cards / tiles ── */
.card { background: #fff; border: 1px solid var(--border-subtle); padding: 2rem; height: 100%; transition: border-color 0.12s; }
.card:hover { border-color: var(--interactive); }
.card .num { font-family: 'IBM Plex Mono', monospace; color: var(--link); font-size: 0.875rem; margin-bottom: 1rem; display: block; }
.card h3 { font-size: 1.25rem; font-weight: 600; margin-bottom: 0.5rem; }
.card p { color: var(--text-secondary); margin-bottom: 0; }
.card a.card-link { display: inline-block; margin-top: 1rem; }

/* tile on layer */
.tile { background: #fff; border: 1px solid var(--border-subtle); padding: 1.75rem; height: 100%; }
.tile h4 { font-size: 1.125rem; margin-bottom: 0.4rem; }
.tile p { color: var(--text-secondary); font-size: 0.9375rem; margin: 0; }

/* ── Feature row (image + text) ── */
.feature-img { width: 100%; border: 1px solid var(--border-subtle); }

/* ── Stat ── */
.stat { border-left: 4px solid var(--interactive); padding-left: 1.25rem; }
.stat .num { font-size: 3rem; font-weight: 300; line-height: 1; color: var(--text-primary); }
.stat .lbl { color: var(--text-secondary); font-size: 0.9375rem; }

/* ── Checklist ── */
.check-list { list-style: none; margin: 0; padding: 0; }
.check-list li { display: flex; align-items: flex-start; gap: 0.75rem; padding: 0.6rem 0; border-bottom: 1px solid var(--border-subtle); color: var(--text-secondary); }
.check-list li::before { content: "✓"; color: var(--success); font-weight: 700; flex-shrink: 0; }

/* ── Step list ── */
.steps { list-style: none; counter-reset: step; margin: 0; padding: 0; }
.steps li { counter-increment: step; padding: 1.25rem 0 1.25rem 3.25rem; position: relative; border-top: 1px solid var(--border-subtle); }
.steps li::before { content: counter(step, decimal-leading-zero); position: absolute; left: 0; top: 1.25rem; font-family: 'IBM Plex Mono', monospace; color: var(--link); font-size: 0.875rem; }
.steps li h4 { margin: 0 0 0.25rem; font-size: 1.0625rem; }
.steps li p { margin: 0; color: var(--text-secondary); }

/* ── Quote ── */
.quote { border-left: 4px solid var(--interactive); padding-left: 1.5rem; font-size: 1.5rem; font-weight: 300; line-height: 1.4; }
.section--dark .quote, .section--blue .quote { border-color: #fff; }

/* ── Partner logos ── */
.logos { display: flex; flex-wrap: wrap; gap: 3rem; align-items: center; }
.logos img { max-height: 30px; filter: grayscale(1); opacity: 0.55; transition: opacity 0.2s, filter 0.2s; }
.logos img:hover { filter: none; opacity: 1; }

/* ── Accordion ── */
.accordion { border-top: 1px solid var(--border-subtle); }
.acc-item { border-bottom: 1px solid var(--border-subtle); }
.acc-q { display: flex; justify-content: space-between; align-items: center; gap: 1rem; cursor: pointer; padding: 1.25rem 0; font-weight: 400; font-size: 1.0625rem; user-select: none; }
.acc-q::after { content: "+"; color: var(--link); font-size: 1.5rem; line-height: 1; flex-shrink: 0; }
.acc-item.is-open .acc-q::after { content: "–"; }
.acc-a { display: none; padding: 0 0 1.5rem; color: var(--text-secondary); max-width: 48rem; }
.acc-item.is-open .acc-a { display: block; }

/* ── Forms (Carbon style) ── */
.field { margin-bottom: 1.25rem; }
.label { display: block; font-size: 0.75rem; color: var(--text-secondary); margin-bottom: 0.4rem; }
.label .req { color: #da1e28; }
.input, .textarea, select.input {
  width: 100%; font-family: inherit; font-size: 1rem; color: var(--text-primary);
  background: var(--layer-01); border: none; border-bottom: 1px solid var(--border-strong);
  padding: 0.75rem 1rem; min-height: 48px;
}
.textarea { min-height: 120px; resize: vertical; }
.input:focus, .textarea:focus { outline: 2px solid var(--interactive); outline-offset: -2px; }
.input.is-error, .textarea.is-error { outline: 2px solid #da1e28; outline-offset: -2px; }
.help-error { color: #da1e28; font-size: 0.75rem; margin: 0.35rem 0 0; display: none; }
.form-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 0 1.5rem; }
@media (max-width: 640px) { .form-grid { grid-template-columns: 1fr; } }
.span-2 { grid-column: 1 / -1; }

/* ── Cookie banner ── */
#cookie-banner { position: fixed; bottom: 0; left: 0; right: 0; background: var(--gray-100); color: rgba(255,255,255,0.9); z-index: 999; }
#cookie-banner-inner { max-width: var(--maxw); margin: 0 auto; padding: 1rem 1.5rem; display: flex; align-items: center; justify-content: space-between; gap: 1.5rem; flex-wrap: wrap; }
#cookie-banner p { font-size: 0.875rem; margin: 0; max-width: 60ch; }
#cookie-banner a { color: #fff; }
#cookie-banner-buttons { display: flex; gap: 1px; flex-shrink: 0; }

/* ── Footer ── */
.site-footer { background: var(--gray-100); color: rgba(255,255,255,0.75); padding: 3.5rem 0 2rem; }
.site-footer a { color: rgba(255,255,255,0.75); text-decoration: none; }
.site-footer a:hover { color: #fff; }
.site-footer .f-heading { font-size: 0.75rem; text-transform: uppercase; letter-spacing: 0.12em; color: rgba(255,255,255,0.5); margin-bottom: 1rem; }
.site-footer ul { list-style: none; margin: 0; padding: 0; }
.site-footer ul li { margin-bottom: 0.5rem; font-size: 0.9375rem; }
.site-footer .brand { color: #fff; font-weight: 600; font-size: 1.0625rem; margin-bottom: 0.5rem; }
.f-divider { height: 1px; background: rgba(255,255,255,0.15); margin: 2.5rem 0 1.5rem; }
.f-copy { font-size: 0.8125rem; color: rgba(255,255,255,0.4); }

/* utility */
.flush-top { padding-top: 0; }
hr.rule { border: none; border-top: 1px solid var(--border-subtle); margin: 0; }