/* =========================================================
   Circular Sulfate Solutions — re-sulfat.de
   Design system: strict, premium B2B business-card aesthetic
   Mobile First. Montserrat. Navy / white / slate.
   ========================================================= */

:root {
    --navy:        #0b1a30;
    --navy-deep:   #07111f;
    --white:       #ffffff;
    --grey-50:     #f8fafc;
    --grey-100:    #f1f5f9;
    --grey-200:    #e2e8f0;
    --grey-300:    #cbd5e1;
    --slate:       #64748b;
    --slate-soft:  rgba(255, 255, 255, 0.72);

    --maxw:        1160px;
    --gutter:      clamp(1.25rem, 5vw, 2.5rem);

    --radius:      4px;
    --line:        1px solid var(--grey-200);
    --shadow-sm:   0 1px 2px rgba(11, 26, 48, 0.04);
    --shadow-md:   0 12px 30px rgba(11, 26, 48, 0.08);
    --shadow-lg:   0 22px 48px rgba(11, 26, 48, 0.14);

    --ease:        cubic-bezier(0.2, 0.6, 0.2, 1);
}

/* ---------- Reset ---------- */
*,
*::before,
*::after { box-sizing: border-box; }

html { -webkit-text-size-adjust: 100%; scroll-behavior: smooth; }

body {
    margin: 0;
    font-family: 'Montserrat', system-ui, -apple-system, 'Segoe UI', Arial, sans-serif;
    font-weight: 400;
    color: var(--navy);
    background-color: var(--white);
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
    text-rendering: optimizeLegibility;
}

h1, h2, h3, p, ul, dl, dd { margin: 0; }
ul { list-style: none; padding: 0; }
a { color: inherit; text-decoration: none; }
img, svg { display: block; max-width: 100%; }
button { font-family: inherit; cursor: pointer; }

:focus-visible {
    outline: 2px solid var(--navy);
    outline-offset: 3px;
    border-radius: 2px;
}

/* ---------- Layout helpers ---------- */
.container {
    width: 100%;
    max-width: var(--maxw);
    margin-inline: auto;
    padding-inline: var(--gutter);
}

.section { padding-block: clamp(3.5rem, 9vw, 6.5rem); }

.section__head { margin-bottom: clamp(2rem, 5vw, 3.25rem); }

.section__label {
    font-size: 0.72rem;
    font-weight: 700;
    letter-spacing: 0.18em;
    text-transform: uppercase;
    color: var(--slate);
    margin-bottom: 0.85rem;
    display: flex;
    align-items: center;
    gap: 0.75rem;
}
.section__label::before {
    content: "";
    width: 1.75rem;
    height: 2px;
    background: var(--navy);
    display: inline-block;
}
.section__label--light { color: var(--slate-soft); }
.section__label--light::before { background: var(--white); }

.section__title {
    font-size: clamp(1.5rem, 4.5vw, 2.25rem);
    font-weight: 700;
    letter-spacing: -0.02em;
    line-height: 1.2;
    max-width: 22ch;
}

/* ---------- Skip link ---------- */
.skip-link {
    position: absolute;
    left: -999px;
    top: 0;
    background: var(--navy);
    color: var(--white);
    padding: 0.75rem 1.25rem;
    z-index: 100;
    font-weight: 600;
}
.skip-link:focus { left: 1rem; top: 1rem; }

/* ---------- Wordmark ---------- */
.wordmark {
    font-weight: 800;
    letter-spacing: -0.01em;
    font-size: 1.15rem;
    line-height: 1;
    color: var(--navy);
}
.wordmark__name { color: var(--navy); }
.wordmark__tld { color: var(--slate); }
.wordmark--lg { font-size: clamp(1.6rem, 5vw, 2.25rem); }

/* ---------- Header ---------- */
.site-header {
    position: sticky;
    top: 0;
    z-index: 50;
    background: rgba(255, 255, 255, 0.86);
    backdrop-filter: saturate(160%) blur(10px);
    border-bottom: var(--line);
}
.header__inner {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 1rem;
    min-height: 64px;
}
.nav { display: none; gap: clamp(1.25rem, 3vw, 2.25rem); }
.nav__link {
    font-size: 0.82rem;
    font-weight: 600;
    letter-spacing: 0.06em;
    text-transform: uppercase;
    color: var(--slate);
    transition: color 0.2s var(--ease);
}
.nav__link:hover { color: var(--navy); }

.lang {
    display: inline-flex;
    align-items: center;
    gap: 0.4rem;
    font-size: 0.78rem;
    font-weight: 700;
    letter-spacing: 0.04em;
}
.lang__btn {
    background: none;
    border: none;
    padding: 0.25rem 0.15rem;
    color: var(--slate);
    font-weight: 700;
    transition: color 0.2s var(--ease);
}
.lang__btn.is-active { color: var(--navy); }
.lang__btn:not(.is-active):hover { color: var(--navy); }
.lang__sep { color: var(--grey-300); }

/* ---------- Hero ---------- */
.hero {
    padding-block: clamp(3.5rem, 11vw, 8rem);
    background:
        radial-gradient(120% 80% at 85% -10%, var(--grey-100) 0%, transparent 55%),
        var(--white);
}
.hero__panel {
    max-width: 46rem;
    border-left: 4px solid var(--navy);
    padding-left: clamp(1.25rem, 4vw, 2.5rem);
}
.eyebrow {
    font-size: 0.74rem;
    font-weight: 700;
    letter-spacing: 0.16em;
    text-transform: uppercase;
    color: var(--slate);
    margin-bottom: 1.5rem;
}
.hero__title {
    font-size: clamp(2.2rem, 8vw, 4.25rem);
    font-weight: 800;
    letter-spacing: -0.03em;
    line-height: 1.04;
    color: var(--navy);
    margin-bottom: 1.5rem;
}
.hero__lead {
    font-size: clamp(1.1rem, 3vw, 1.5rem);
    font-weight: 500;
    line-height: 1.4;
    color: var(--navy);
    max-width: 36ch;
    margin-bottom: 1.25rem;
}
.hero__note {
    font-size: clamp(0.95rem, 2.2vw, 1.08rem);
    color: var(--slate);
    max-width: 50ch;
    margin-bottom: 2.5rem;
}
.hero__actions { display: flex; flex-wrap: wrap; gap: 0.85rem; }

/* ---------- Buttons ---------- */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 0.9rem 1.6rem;
    font-size: 0.84rem;
    font-weight: 600;
    letter-spacing: 0.05em;
    text-transform: uppercase;
    border-radius: var(--radius);
    border: 1px solid transparent;
    transition: transform 0.2s var(--ease), background-color 0.2s var(--ease),
                color 0.2s var(--ease), box-shadow 0.2s var(--ease);
}
.btn--primary {
    background: var(--navy);
    color: var(--white);
    box-shadow: var(--shadow-sm);
}
.btn--primary:hover {
    background: var(--navy-deep);
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}
.btn--ghost {
    background: transparent;
    color: var(--navy);
    border-color: var(--grey-300);
}
.btn--ghost:hover { border-color: var(--navy); transform: translateY(-2px); }

/* ---------- Grids ---------- */
.grid { display: grid; gap: clamp(1rem, 2.5vw, 1.75rem); }
.grid--3 { grid-template-columns: 1fr; }
.grid--2 { grid-template-columns: 1fr; }

/* ---------- Area cards ---------- */
.areas { background: var(--grey-100); }
.area-card {
    background: var(--white);
    border: var(--line);
    border-top: 3px solid var(--navy);
    border-radius: var(--radius);
    padding: clamp(1.5rem, 4vw, 2.25rem);
    box-shadow: var(--shadow-sm);
    transition: transform 0.25s var(--ease), box-shadow 0.25s var(--ease);
}
.area-card:hover { transform: translateY(-4px); box-shadow: var(--shadow-md); }
.area-card__no {
    font-size: 0.8rem;
    font-weight: 800;
    letter-spacing: 0.1em;
    color: var(--grey-300);
    display: block;
    margin-bottom: 1.5rem;
}
.area-card__title {
    font-size: 1.18rem;
    font-weight: 700;
    letter-spacing: -0.01em;
    line-height: 1.3;
    margin-bottom: 0.75rem;
}
.area-card__text { color: var(--slate); font-size: 0.96rem; }

/* ---------- Circular economy band ---------- */
.band {
    background:
        radial-gradient(circle at 1px 1px, rgba(255, 255, 255, 0.07) 1px, transparent 0) 0 0 / 26px 26px,
        linear-gradient(160deg, var(--navy) 0%, var(--navy-deep) 100%);
    color: var(--white);
}
.band__grid { display: grid; gap: clamp(2.25rem, 6vw, 4rem); }
.band__title {
    font-size: clamp(1.6rem, 4.5vw, 2.4rem);
    font-weight: 700;
    letter-spacing: -0.02em;
    line-height: 1.18;
    margin-bottom: 1.25rem;
}
.band__text { color: var(--slate-soft); max-width: 58ch; font-size: 1.02rem; }

.principles { display: grid; gap: 1.5rem; }
.principle {
    display: grid;
    gap: 0.35rem;
    padding-left: 1.25rem;
    border-left: 2px solid rgba(255, 255, 255, 0.22);
}
.principle__title {
    font-weight: 700;
    font-size: 1.02rem;
    letter-spacing: -0.01em;
}
.principle__text { color: var(--slate-soft); font-size: 0.92rem; }

/* ---------- Contact cards ---------- */
.contact-card {
    background: var(--white);
    border: var(--line);
    border-left: 4px solid var(--navy);
    border-radius: var(--radius);
    padding: clamp(1.75rem, 4vw, 2.5rem);
    box-shadow: var(--shadow-sm);
    transition: transform 0.25s var(--ease), box-shadow 0.25s var(--ease);
}
.contact-card:hover { transform: translateY(-4px); box-shadow: var(--shadow-md); }
.contact-card__name {
    font-size: 1.3rem;
    font-weight: 700;
    letter-spacing: -0.01em;
    text-transform: uppercase;
}
.contact-card__role {
    font-size: 0.74rem;
    font-weight: 600;
    letter-spacing: 0.14em;
    text-transform: uppercase;
    color: var(--slate);
    margin-top: 0.35rem;
    margin-bottom: 1.5rem;
}
.contact-card__list { display: grid; gap: 0.65rem; }
.contact-card__row {
    display: grid;
    grid-template-columns: 1.5rem 1fr;
    align-items: baseline;
    gap: 0.5rem;
}
.contact-card__row dt {
    font-weight: 800;
    font-size: 0.78rem;
    color: var(--navy);
}
.contact-card__row dd { margin: 0; }
.contact-card__row a {
    font-weight: 500;
    color: var(--navy);
    border-bottom: 1px solid transparent;
    transition: border-color 0.2s var(--ease);
    word-break: break-word;
}
.contact-card__row a:hover { border-color: var(--navy); }

/* General enquiries line */
.contact-general {
    margin-top: 1.1rem;
    font-size: 0.98rem;
    color: var(--slate);
}
.contact-general a {
    font-weight: 600;
    color: var(--navy);
    border-bottom: 1px solid var(--grey-300);
    transition: border-color 0.2s var(--ease);
}
.contact-general a:hover { border-color: var(--navy); }

/* ---------- Footer ---------- */
.footer {
    background: var(--grey-50);
    border-top: var(--line);
    padding-top: clamp(3rem, 7vw, 4.5rem);
    padding-bottom: 2rem;
}
.footer__inner {
    display: grid;
    gap: 2.5rem;
    padding-bottom: 2.5rem;
    border-bottom: var(--line);
}
.footer__tagline {
    color: var(--slate);
    max-width: 42ch;
    margin-top: 1rem;
    font-size: 0.96rem;
}
.footer__legal-label {
    font-size: 0.7rem;
    font-weight: 700;
    letter-spacing: 0.14em;
    text-transform: uppercase;
    color: var(--slate);
    margin-bottom: 0.65rem;
}
.footer__legal-text { color: var(--navy); font-size: 0.92rem; line-height: 1.8; }
.footer__legal-text a { border-bottom: 1px solid var(--grey-300); }
.footer__legal-text a:hover { border-color: var(--navy); }

.footer__bottom {
    display: flex;
    flex-wrap: wrap;
    gap: 0.75rem 1.5rem;
    justify-content: space-between;
    align-items: center;
    padding-top: 1.75rem;
}
.footer__copy,
.footer__region {
    font-size: 0.78rem;
    font-weight: 600;
    letter-spacing: 0.06em;
    color: var(--slate);
    text-transform: uppercase;
}

/* =========================================================
   Responsive — Mobile First breakpoints
   ========================================================= */
@media (min-width: 640px) {
    .grid--2 { grid-template-columns: repeat(2, 1fr); }
}

@media (min-width: 860px) {
    .nav { display: inline-flex; }
    .grid--3 { grid-template-columns: repeat(3, 1fr); }
    .band__grid { grid-template-columns: 1.35fr 1fr; align-items: start; }
    .principles { gap: 1.75rem; }
    .footer__inner { grid-template-columns: 1.5fr 1fr; align-items: start; }
}

/* ---------- Reduced motion ---------- */
@media (prefers-reduced-motion: reduce) {
    html { scroll-behavior: auto; }
    *, *::before, *::after {
        animation-duration: 0.001ms !important;
        transition-duration: 0.001ms !important;
    }
}