/* ==========================================================================
   BTB TECHNICS — Design System
   "Monochrome Atelier" — editorial, zwart-wit, Didone-serif + grotesk-sans.
   Bouw hier bovenop verder: elke sectie/component hergebruikt deze tokens.
   ========================================================================== */

/* --------------------------------------------------------------------
   1. Reset
   -------------------------------------------------------------------- */
*, *::before, *::after { box-sizing: border-box; }
* { margin: 0; padding: 0; }
html { -webkit-text-size-adjust: 100%; scroll-behavior: smooth; }
html, body { max-width: 100%; overflow-x: hidden; }
body { min-height: 100vh; line-height: 1.5; -webkit-font-smoothing: antialiased; -moz-osx-font-smoothing: grayscale; }
img, picture, video { display: block; max-width: 100%; height: auto; }
input, button, textarea, select { font: inherit; color: inherit; }
a { color: inherit; text-decoration: none; }
ul, ol { list-style: none; }
button { background: none; border: 0; cursor: pointer; }
table { border-collapse: collapse; width: 100%; }

/* --------------------------------------------------------------------
   2. Tokens — kleur, typografie, spacing, motion
   -------------------------------------------------------------------- */
:root {
    /* Kleur — strikt zwart/wit + grijstinten voor diepte (géén derde merkkleur) */
    --c-black:        #000000;
    --c-ink:           #0a0a0a;   /* near-black, gebruikt voor tekst/achtergronden i.p.v. puur zwart */
    --c-white:         #ffffff;
    --c-off-white:     #f4f3f1;   /* zeer licht gebroken wit, subtiele sectie-afwisseling */
    --c-gray-800:      #1c1c1c;
    --c-gray-600:      #4a4a4a;
    --c-gray-400:      #8a8a8a;
    --c-gray-200:      #d9d7d3;   /* hairline op licht */
    --c-gray-900-line: #2b2b2b;   /* hairline op donker */

    /* Typografie */
    --font-display: 'Bodoni Moda', 'Times New Roman', Georgia, serif;
    --font-body: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;

    --fs-display-xl: clamp(3.25rem, 3rem + 5vw, 8.5rem);
    --fs-display-lg: clamp(2.5rem, 2.1rem + 4vw, 5.75rem);
    --fs-display-md: clamp(1.9rem, 1.6rem + 2vw, 3.25rem);
    --fs-display-sm: clamp(1.5rem, 1.3rem + 1vw, 2.15rem);
    --fs-lead:       clamp(1.15rem, 1.05rem + 0.4vw, 1.5rem);
    --fs-body-lg:    1.125rem;
    --fs-body:       1rem;
    --fs-small:      0.875rem;
    --fs-micro:      0.75rem;

    --lh-tight: 1.05;
    --lh-snug:  1.2;
    --lh-normal: 1.6;

    --ls-wide:  0.14em;
    --ls-wider: 0.24em;

    /* Spacing-schaal */
    --sp-3xs: 0.25rem;
    --sp-2xs: 0.5rem;
    --sp-xs:  0.75rem;
    --sp-sm:  1rem;
    --sp-md:  1.5rem;
    --sp-lg:  2.5rem;
    --sp-xl:  4rem;
    --sp-2xl: 6rem;
    --sp-3xl: 9rem;

    /* Layout */
    --container-max: 1440px;
    --container-pad: clamp(1.25rem, 4vw, 4rem);
    --header-h: 92px;
    --header-h-mobile: 72px;

    /* Motion */
    --ease-atelier: cubic-bezier(0.16, 1, 0.3, 1);
    --dur-fast: 220ms;
    --dur-base: 420ms;
    --dur-slow: 700ms;
}

/* --------------------------------------------------------------------
   3. Basistypografie
   -------------------------------------------------------------------- */
body {
    background: var(--c-white);
    color: var(--c-ink);
    font-family: var(--font-body);
    font-size: var(--fs-body);
    font-weight: 400;
}

h1, h2, h3, h4,
.h1, .h2, .h3, .h4 {
    font-family: var(--font-display);
    font-weight: 500;
    line-height: var(--lh-tight);
    letter-spacing: -0.01em;
    text-wrap: balance;
    overflow-wrap: break-word;
    hyphens: auto;
}

h1, .h1 { font-size: var(--fs-display-xl); }
h2, .h2 { font-size: var(--fs-display-lg); }
h3, .h3 { font-size: var(--fs-display-md); }
h4, .h4 { font-size: var(--fs-display-sm); font-weight: 600; }

p { max-width: 62ch; }
p.lead, .lead { font-size: var(--fs-lead); line-height: var(--lh-snug); font-weight: 400; }

.eyebrow {
    display: inline-block;
    font-family: var(--font-body);
    font-size: var(--fs-micro);
    font-weight: 600;
    letter-spacing: var(--ls-wider);
    text-transform: uppercase;
    color: var(--c-gray-600);
}

.serif-quote {
    font-family: var(--font-display);
    font-style: italic;
    font-weight: 400;
    font-size: var(--fs-display-md);
    line-height: var(--lh-snug);
}

/* Skip-link (a11y) */
.skip-link {
    position: absolute;
    left: -999px;
    top: 0;
    background: var(--c-black);
    color: var(--c-white);
    padding: var(--sp-xs) var(--sp-sm);
    z-index: 999;
}
.skip-link:focus { left: var(--sp-sm); top: var(--sp-sm); }

/* --------------------------------------------------------------------
   4. Layout-hulpmiddelen
   -------------------------------------------------------------------- */
.container {
    max-width: var(--container-max);
    margin-inline: auto;
    padding-inline: var(--container-pad);
}

.section { padding-block: var(--sp-2xl); }
.section--tight { padding-block: var(--sp-xl); }
.section--black { background: var(--c-ink); color: var(--c-white); }
.section--off { background: var(--c-off-white); }

.hairline {
    border: 0;
    border-top: 1px solid var(--c-gray-200);
}
.section--black .hairline,
.on-dark .hairline { border-top-color: var(--c-gray-900-line); }

/* Asymmetrische editorial-grid: twee kolommen, bewust ongelijk verdeeld */
.split {
    display: grid;
    gap: var(--sp-xl);
    align-items: center;
}
@media (min-width: 900px) {
    .split { grid-template-columns: 1fr 1fr; }
    .split--60-40 { grid-template-columns: 3fr 2fr; }
    .split--40-60 { grid-template-columns: 2fr 3fr; }
    .split--reverse { direction: rtl; }
    .split--reverse > * { direction: ltr; }
}

.grid-auto {
    display: grid;
    gap: var(--sp-md);
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
}

/* --------------------------------------------------------------------
   5. Knoppen / CTA — scherpe hoeken, geen schaduw, geen gradient
   -------------------------------------------------------------------- */
.btn {
    display: inline-flex;
    align-items: center;
    gap: var(--sp-2xs);
    font-family: var(--font-body);
    font-size: var(--fs-small);
    font-weight: 600;
    letter-spacing: var(--ls-wide);
    text-transform: uppercase;
    padding: 1rem 1.75rem;
    border: 1px solid var(--c-ink);
    border-radius: 1px;
    transition: background var(--dur-fast) var(--ease-atelier),
                color var(--dur-fast) var(--ease-atelier),
                border-color var(--dur-fast) var(--ease-atelier);
    white-space: nowrap;
}

.btn--black { background: var(--c-ink); color: var(--c-white); }
.btn--black:hover { background: var(--c-white); color: var(--c-ink); }

.btn--white { background: var(--c-white); color: var(--c-ink); border-color: var(--c-ink); }
.btn--white:hover { background: var(--c-ink); color: var(--c-white); }

.btn--outline { background: transparent; color: currentColor; border-color: currentColor; }
.btn--outline:hover { background: currentColor; }
.btn--outline:hover { color: var(--c-ink); }
.on-dark .btn--outline:hover { color: var(--c-ink); }

.btn--ghost {
    border-color: transparent;
    padding-inline: 0;
    text-transform: none;
    letter-spacing: 0;
    font-weight: 500;
    font-size: var(--fs-body);
    position: relative;
}
.btn--ghost::after {
    content: '';
    position: absolute;
    left: 0; right: 100%; bottom: -2px;
    height: 1px;
    background: currentColor;
    transition: right var(--dur-base) var(--ease-atelier);
}
.btn--ghost:hover::after { right: 0; }

/* --------------------------------------------------------------------
   6. Afbeeldingen — hover-zoom utility
   -------------------------------------------------------------------- */
.img-zoom {
    overflow: hidden;
    display: block;
    position: relative;
    background: var(--c-gray-800);
}
.img-zoom img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform var(--dur-slow) var(--ease-atelier);
    transform: scale(1);
}
.img-zoom:hover img { transform: scale(1.06); }

.img-frame--tall { aspect-ratio: 3 / 4; }
.img-frame--wide { aspect-ratio: 16 / 10; }
.img-frame--square { aspect-ratio: 1 / 1; }

/* --------------------------------------------------------------------
   7. Logo-lockup (twee varianten: licht glyph / donker glyph)
   -------------------------------------------------------------------- */
.logo-mark {
    height: 34px;
    width: auto;
    display: block;
}
.logo-mark--dark { display: none; }
.logo-mark--light { display: block; }

/* --------------------------------------------------------------------
   8. Site-header (fixed) + toggle-knop
   -------------------------------------------------------------------- */
.site-header {
    position: fixed;
    inset-inline: 0;
    top: 0;
    z-index: 100;
    height: var(--header-h-mobile);
    display: flex;
    align-items: center;
    transition: background var(--dur-base) var(--ease-atelier),
                border-color var(--dur-base) var(--ease-atelier);
    border-bottom: 1px solid transparent;
}
@media (min-width: 900px) { .site-header { height: var(--header-h); } }

.site-header__inner {
    width: 100%;
    max-width: var(--container-max);
    margin-inline: auto;
    padding-inline: var(--container-pad);
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: var(--sp-md);
}

/* Solide variant: witte achtergrond vanaf het begin (binnenpagina's) */
.site-header--solid {
    background: var(--c-white);
    border-bottom-color: var(--c-gray-200);
    color: var(--c-ink);
}
.site-header--solid .logo-mark--dark { display: block; }
.site-header--solid .logo-mark--light { display: none; }

/* Transparante variant: start doorzichtig met wit glyph over donkere hero */
.site-header--transparent {
    background: transparent;
    color: var(--c-white);
}
.site-header--transparent .logo-mark--light { display: block; }
.site-header--transparent .logo-mark--dark { display: none; }

.site-header--transparent.is-scrolled {
    background: var(--c-white);
    color: var(--c-ink);
    border-bottom-color: var(--c-gray-200);
}
.site-header--transparent.is-scrolled .logo-mark--light { display: none; }
.site-header--transparent.is-scrolled .logo-mark--dark { display: block; }

.site-header__phone {
    display: none;
    font-family: var(--font-body);
    font-size: var(--fs-small);
    letter-spacing: 0.02em;
}
@media (min-width: 700px) { .site-header__phone { display: block; } }

/* Content onder een vaste, solide header moet niet onder de header schuiven;
   transparante-header-pagina's laten hun hero net wél onder de header starten. */
body:not(.header-is-transparent) main { padding-top: var(--header-h-mobile); }
@media (min-width: 900px) {
    body:not(.header-is-transparent) main { padding-top: var(--header-h); }
}

/* Menu-toggle knop: twee streepjes, geen hamburger-emoji, puur CSS/typografie */
.nav-toggle {
    display: flex;
    align-items: center;
    gap: var(--sp-xs);
    font-family: var(--font-body);
    font-size: var(--fs-small);
    font-weight: 600;
    letter-spacing: var(--ls-wide);
    text-transform: uppercase;
    color: inherit;
}
.nav-toggle__icon {
    display: inline-flex;
    flex-direction: column;
    gap: 5px;
    width: 26px;
}
.nav-toggle__icon span {
    display: block;
    height: 1px;
    width: 100%;
    background: currentColor;
    transition: transform var(--dur-base) var(--ease-atelier), opacity var(--dur-base) var(--ease-atelier);
}
.nav-toggle[aria-expanded="true"] .nav-toggle__icon span:first-child {
    transform: translateY(3px) rotate(45deg);
}
.nav-toggle[aria-expanded="true"] .nav-toggle__icon span:last-child {
    transform: translateY(-3px) rotate(-45deg);
}

/* --------------------------------------------------------------------
   9. Fullscreen overlay-navigatie — "het gordijn"
   -------------------------------------------------------------------- */
.nav-overlay {
    position: fixed;
    inset: 0;
    z-index: 200;
    background: var(--c-ink);
    color: var(--c-white);
    display: flex;
    flex-direction: column;
    padding: var(--sp-md) 0 var(--sp-lg);
    opacity: 0;
    visibility: hidden;
    transform: translateY(-2%);
    transition: opacity var(--dur-slow) var(--ease-atelier),
                visibility 0s linear var(--dur-slow),
                transform var(--dur-slow) var(--ease-atelier);
    overflow-y: auto;
}
.nav-overlay.is-open {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
    transition: opacity var(--dur-slow) var(--ease-atelier),
                visibility 0s linear 0s,
                transform var(--dur-slow) var(--ease-atelier);
}

.nav-overlay__top {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding-inline: var(--container-pad);
    padding-block: var(--sp-sm);
}
.nav-overlay__brand {
    font-family: var(--font-display);
    font-size: var(--fs-body-lg);
    letter-spacing: 0.03em;
}
.nav-overlay__close {
    font-size: 2rem;
    line-height: 1;
    color: var(--c-white);
    padding: var(--sp-2xs);
    transition: transform var(--dur-fast) var(--ease-atelier);
}
.nav-overlay__close:hover { transform: rotate(90deg); }

.nav-overlay__body {
    flex: 1;
    display: flex;
    flex-direction: column;
    justify-content: space-between;
    gap: var(--sp-xl);
    padding-inline: var(--container-pad);
    padding-block: var(--sp-lg) var(--sp-sm);
}

.nav-overlay__list {
    display: flex;
    flex-direction: column;
    gap: 0.15em;
}
.nav-overlay__link {
    font-family: var(--font-display);
    font-size: clamp(2.5rem, 5vw + 1rem, 5.5rem);
    line-height: 1.15;
    font-weight: 500;
    color: var(--c-white);
    display: inline-block;
    position: relative;
    transition: opacity var(--dur-fast) var(--ease-atelier), padding-left var(--dur-base) var(--ease-atelier);
    opacity: 0.55;
}
.nav-overlay__link:hover,
.nav-overlay__link:focus-visible,
.nav-overlay__link.is-current {
    opacity: 1;
    padding-left: 0.3em;
}

.nav-overlay__meta {
    display: grid;
    gap: var(--sp-md);
    font-size: var(--fs-small);
    color: var(--c-gray-400);
}
@media (min-width: 700px) {
    .nav-overlay__meta { grid-template-columns: repeat(3, minmax(0, 220px)); }
}
.nav-overlay__meta-block { display: flex; flex-direction: column; gap: 0.35rem; }
.nav-overlay__meta-block a:hover { color: var(--c-white); }
.nav-overlay__meta-label {
    font-family: var(--font-body);
    font-size: var(--fs-micro);
    letter-spacing: var(--ls-wider);
    text-transform: uppercase;
    color: var(--c-gray-600);
}

/* Voorkom scroll van de pagina eronder terwijl het menu open staat */
body.nav-open { overflow: hidden; }

/* --------------------------------------------------------------------
   10. Scroll-reveal (samenspel met script.js / IntersectionObserver)
   -------------------------------------------------------------------- */
.reveal {
    opacity: 0;
    transform: translateY(28px);
    transition: opacity var(--dur-slow) var(--ease-atelier),
                transform var(--dur-slow) var(--ease-atelier);
}
.reveal.is-visible {
    opacity: 1;
    transform: translateY(0);
}
@media (prefers-reduced-motion: reduce) {
    .reveal { opacity: 1; transform: none; transition: none; }
    .img-zoom img { transition: none; }
}

/* --------------------------------------------------------------------
   11. Site-footer
   -------------------------------------------------------------------- */
.site-footer {
    background: var(--c-ink);
    color: var(--c-white);
    padding-top: var(--sp-2xl);
}
.site-footer__top {
    max-width: var(--container-max);
    margin-inline: auto;
    padding-inline: var(--container-pad);
    display: grid;
    gap: var(--sp-xl);
    padding-bottom: var(--sp-xl);
}
@media (min-width: 900px) {
    .site-footer__top { grid-template-columns: 1.3fr 1fr 1fr; }
}
.site-footer__brand .logo-mark { height: 30px; margin-bottom: var(--sp-sm); }
.site-footer__tagline { color: var(--c-gray-400); font-size: var(--fs-small); max-width: 32ch; }

.site-footer__nav ul { display: flex; flex-direction: column; gap: 0.6rem; }
.site-footer__nav a { font-size: var(--fs-body); color: var(--c-gray-400); transition: color var(--dur-fast) var(--ease-atelier); }
.site-footer__nav a:hover { color: var(--c-white); }

.site-footer__contact address { font-style: normal; color: var(--c-gray-400); line-height: 1.9; }
.site-footer__contact a:hover { color: var(--c-white); }
.site-footer__meta-label {
    display: block;
    font-size: var(--fs-micro);
    letter-spacing: var(--ls-wider);
    text-transform: uppercase;
    color: var(--c-gray-600);
    margin-bottom: 0.6rem;
}

.site-footer__hairline {
    max-width: var(--container-max);
    margin-inline: auto;
    border-top: 1px solid var(--c-gray-900-line);
}

.site-footer__bottom {
    max-width: var(--container-max);
    margin-inline: auto;
    padding-inline: var(--container-pad);
    padding-block: var(--sp-md);
    display: flex;
    flex-wrap: wrap;
    gap: var(--sp-sm);
    justify-content: space-between;
    font-size: var(--fs-micro);
    color: var(--c-gray-600);
    letter-spacing: 0.02em;
}
.site-footer__credit a {
    color: var(--c-gray-600);
    text-decoration: underline;
    text-underline-offset: 3px;
    transition: color var(--dur-fast) var(--ease-atelier);
}
.site-footer__credit a:hover { color: var(--c-white); }