/* Xyncema Volt — technical, diagram-led. Cool light ground, deep navy type, a sun orange used for
   buttons, bars and diagram flow (always with dark text on it), and working shown in monospace-like tables. */

[data-theme="solar"] body { background: var(--bg); color: var(--text); font-family: var(--font-body); }
.vt-wrap { width: min(100% - 2.5rem, 76rem); margin-inline: auto; }
.vt-muted { color: var(--muted); }
.vt-h1, .vt-h2, .vt-h3, .vt-h4 { font-family: var(--font-heading); font-weight: 700; line-height: 1.1; margin: 0; letter-spacing: -0.02em; }
.vt-h1 { font-size: clamp(2.1rem, 1.3rem + 3.2vw, 3.6rem); line-height: 1.02; font-weight: 800; }
.vt-h2 { font-size: clamp(1.5rem, 1.15rem + 1.4vw, 2.2rem); }
.vt-h3 { font-size: clamp(1.08rem, 1rem + 0.4vw, 1.25rem); }
.vt-h4 { font-size: 0.95rem; }
.vt-eyebrow { display: inline-flex; align-items: center; gap: 0.5rem; font: 700 0.75rem/1.3 var(--font-heading); letter-spacing: 0.1em; text-transform: uppercase; color: var(--primary-ink); margin: 0 0 0.9rem; }
.vt-eyebrow::before { content: ""; width: 0.6rem; height: 0.6rem; background: var(--primary); border-radius: 50%; }
.vt-lead { font-size: clamp(1.02rem, 0.98rem + 0.3vw, 1.18rem); line-height: 1.65; color: var(--muted); }
.vt-num { font-variant-numeric: tabular-nums; }

/* ---------- Header ---------- */
.vt-notice { background: var(--surface-2); color: var(--on-surface-2); font-size: 0.8125rem; line-height: 1.45; padding: 0.55rem 0; }
.vt-notice p { margin: 0; }
.vt-header { position: sticky; top: 0; z-index: 30; background: rgba(247, 249, 250, 0.94); backdrop-filter: blur(8px); border-bottom: 1px solid var(--border); }
.vt-header__row { display: flex; align-items: center; gap: 1.25rem; min-height: 4.25rem; }
.vt-logo { display: flex; align-items: center; gap: 0.55rem; text-decoration: none; color: var(--text); font-family: var(--font-heading); font-weight: 800; font-size: 1.2rem; margin-right: auto; letter-spacing: -0.03em; }
.vt-logo i { width: 1.5rem; height: 1.5rem; border-radius: 50%; background: var(--primary); box-shadow: 0 0 0 3px var(--bg), 0 0 0 4.5px var(--primary); flex: none; }
.vt-logo small { font-family: var(--font-body); font-weight: 500; font-size: 0.75rem; color: var(--muted); letter-spacing: 0; }
.vt-nav { display: flex; gap: 1.35rem; }
.vt-nav a { color: var(--text); text-decoration: none; font-size: 0.9375rem; font-weight: 500; padding: 0.35rem 0; border-bottom: 2px solid transparent; }
.vt-nav a:hover { border-bottom-color: var(--primary); }
.vt-nav a[aria-current="page"] { border-bottom-color: var(--primary); }
.vt-toggle { display: none; background: none; border: 1px solid var(--border); border-radius: var(--radius); width: 2.75rem; height: 2.75rem; padding: 0.6rem; color: var(--text); cursor: pointer; }
.vt-toggle svg { width: 100%; height: 100%; }
.vt-mobile { display: none; flex-direction: column; padding-bottom: 1rem; }
.vt-mobile a { padding: 0.8rem 0; border-top: 1px solid var(--border); color: var(--text); text-decoration: none; }
.vt-mobile[data-open] { display: flex; }
@media (max-width: 920px) { .vt-nav, .vt-header .vt-btn { display: none; } .vt-toggle { display: block; } }

/* ---------- Buttons ---------- */
.vt-btn { display: inline-flex; align-items: center; justify-content: center; gap: 0.5rem; min-height: 2.9rem; padding: 0 1.3rem; border-radius: var(--radius-btn); border: 1px solid var(--primary); background: var(--primary); color: var(--on-primary); font: 700 0.9375rem/1 var(--font-heading); text-decoration: none; cursor: pointer; }
.vt-btn:hover { background: #E07A14; border-color: #E07A14; }
.vt-btn--line { background: transparent; color: var(--text); border-color: var(--text); }
.vt-btn--line:hover { background: var(--text); color: var(--bg); border-color: var(--text); }
.vt-btn svg { width: 1.05rem; height: 1.05rem; }
.vt-link { color: var(--primary-ink); font-weight: 600; text-decoration: underline; text-underline-offset: 3px; }

/* ---------- Sections ---------- */
.vt-section { padding-block: clamp(3rem, 2rem + 4vw, 5.5rem); }
.vt-section + .vt-section { border-top: 1px solid var(--border); }
.vt-section--white { background: var(--surface); }
.vt-section--dark { background: var(--surface-2); color: var(--on-surface-2); }
.vt-section--dark .vt-lead, .vt-section--dark .vt-muted { color: var(--on-surface-2); opacity: 0.8; }
.vt-section--dark .vt-eyebrow { color: var(--primary-on-dark); }
.vt-head { display: grid; gap: 0.85rem; margin-bottom: 2.25rem; max-width: 46rem; }

/* ---------- Hero ---------- */
.vt-hero { position: relative; background: var(--surface-2); color: var(--on-surface-2); overflow: hidden; }
.vt-hero__media img { width: 100%; height: min(64vh, 600px); object-fit: cover; display: block; }
.vt-hero__media::after { content: ""; position: absolute; inset: 0; background: linear-gradient(90deg, rgba(16,33,46,.92) 0%, rgba(16,33,46,.7) 45%, rgba(16,33,46,.1) 85%); }
.vt-hero__inner { position: absolute; inset: 0; z-index: 1; display: grid; align-content: center; }
.vt-hero .vt-eyebrow { color: var(--primary-on-dark); }
.vt-hero h1 { max-width: 15ch; }
.vt-hero__copy { max-width: 44ch; line-height: 1.7; margin: 1.1rem 0 1.75rem; opacity: 0.9; }
.vt-hero__actions { display: flex; flex-wrap: wrap; gap: 0.7rem; }
.vt-hero .vt-btn--line { color: var(--on-surface-2); border-color: rgba(247,249,250,.5); }
.vt-hero .vt-btn--line:hover { background: var(--on-surface-2); color: var(--text); }
@media (max-width: 760px) { .vt-hero__media img { height: min(78vh, 640px); } .vt-hero__media::after { background: linear-gradient(180deg, rgba(16,33,46,.55) 0%, rgba(16,33,46,.92) 60%); } }

/* ---------- Sizing tool ---------- */
.vt-tool { display: grid; grid-template-columns: minmax(0, 1fr) minmax(0, 27rem); gap: clamp(1.25rem, 3vw, 2rem); align-items: start; }
.vt-panel { background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius); padding: clamp(1.15rem, 2.5vw, 1.6rem); }
.vt-form { display: grid; gap: 1.6rem; }
.vt-set { border: 0; margin: 0; padding: 0; }
.vt-set > legend { font: 700 0.75rem/1 var(--font-heading); letter-spacing: 0.1em; text-transform: uppercase; padding: 0; margin-bottom: 0.8rem; }
.vt-opts { display: grid; gap: 0.5rem; grid-template-columns: repeat(3, minmax(0, 1fr)); }
.vt-opts--2 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
.vt-opts label { display: grid; gap: 0.15rem; padding: 0.75rem 0.85rem; border: 1px solid var(--border); border-radius: var(--radius); cursor: pointer; background: var(--bg); }
.vt-opts label:hover { border-color: var(--muted); }
.vt-opts input { position: absolute; opacity: 0; width: 0; height: 0; }
.vt-opts b { font-weight: 700; font-size: 0.9375rem; }
.vt-opts span { font-size: 0.8125rem; color: var(--muted); line-height: 1.45; }
.vt-opts label:has(input:checked) { border-color: var(--text); box-shadow: inset 0 0 0 1px var(--text); background: #FFF5EA; }
.vt-opts label:has(input:focus-visible) { outline: 2px solid var(--focus); outline-offset: 2px; }
.vt-fields { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 1rem; }
.vt-unit { position: relative; }
.vt-unit .xy-input { padding-right: 3.5rem; }
.vt-unit span { position: absolute; right: 0.85rem; top: 50%; transform: translateY(-50%); color: var(--muted); font-size: 0.875rem; pointer-events: none; }
.vt-derived { font-size: 0.875rem; color: var(--muted); margin: 0.5rem 0 0; }
.vt-derived b { color: var(--text); }
@media (max-width: 980px) { .vt-tool { grid-template-columns: minmax(0, 1fr); } }
@media (max-width: 640px) { .vt-opts, .vt-opts--2, .vt-fields { grid-template-columns: minmax(0, 1fr); } }

/* ---------- Result ---------- */
.vt-result { position: sticky; top: 5.5rem; display: grid; gap: 1.1rem; }
.vt-big { display: grid; gap: 0.3rem; }
.vt-big b { font-family: var(--font-heading); font-size: clamp(2rem, 1.5rem + 1.6vw, 2.6rem); font-weight: 800; line-height: 1; letter-spacing: -0.03em; }
.vt-big span { color: var(--muted); font-size: 0.9375rem; }
.vt-limit { display: inline-flex; align-items: center; gap: 0.45rem; font: 700 0.8125rem/1 var(--font-heading); padding: 0.45rem 0.65rem; border-radius: 999px; background: #FFF1E0; color: var(--primary-ink); justify-self: start; }
.vt-bars { display: grid; gap: 0.7rem; }
.vt-bar { display: grid; gap: 0.3rem; font-size: 0.8125rem; }
.vt-bar__top { display: flex; justify-content: space-between; gap: 1rem; }
.vt-bar__top b { font-variant-numeric: tabular-nums; }
.vt-bar__track { height: 0.7rem; background: var(--bg); border: 1px solid var(--border); border-radius: 999px; overflow: hidden; }
.vt-bar__fill { height: 100%; background: var(--primary); border-radius: 999px; }
.vt-bar__fill--roof { background: var(--text); }
.vt-working { border-top: 1px solid var(--border); padding-top: 0.9rem; }
.vt-working summary { cursor: pointer; font: 700 0.875rem/1.4 var(--font-heading); }
.vt-lines { list-style: none; margin: 0.8rem 0 0; padding: 0; display: grid; }
.vt-lines li { display: grid; grid-template-columns: minmax(0, 1fr) auto; gap: 1rem; padding: 0.45rem 0; border-bottom: 1px dashed var(--border); font-size: 0.8375rem; line-height: 1.45; }
.vt-lines li small { display: block; color: var(--muted); }
.vt-lines li span:last-child { font-variant-numeric: tabular-nums; font-weight: 600; text-align: right; white-space: nowrap; }
.vt-note { font-size: 0.875rem; line-height: 1.55; padding: 0.7rem 0.85rem; border-radius: var(--radius); background: var(--bg); border-left: 3px solid var(--primary); margin: 0; }
.vt-note--warn { border-left-color: var(--danger); }
@media (max-width: 980px) { .vt-result { position: static; } }

/* ---------- Refusals ---------- */
.vt-refuse { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 1rem; }
.vt-refuse > div { border-top: 3px solid var(--primary); padding-top: 1rem; display: grid; gap: 0.45rem; }
.vt-refuse p { margin: 0; line-height: 1.65; font-size: 0.9375rem; }
.vt-refuse h3 { color: var(--on-surface-2); }
@media (max-width: 980px) { .vt-refuse { grid-template-columns: repeat(2, minmax(0, 1fr)); } }
@media (max-width: 560px) { .vt-refuse { grid-template-columns: minmax(0, 1fr); } }

/* ---------- Diagrams ---------- */
.vt-diagram { margin: 0; background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius); padding: 1rem; }
.vt-diagram svg { width: 100%; height: auto; display: block; }
.vt-diagram figcaption { font-size: 0.875rem; color: var(--muted); line-height: 1.55; margin-top: 0.6rem; }

/* ---------- Systems ---------- */
.vt-systems { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 1rem; }
.vt-sys { background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius); overflow: hidden; display: grid; grid-template-rows: auto 1fr; }
.vt-sys img { width: 100%; aspect-ratio: 16 / 8; object-fit: cover; }
.vt-sys__body { padding: 1.2rem; display: grid; gap: 0.65rem; align-content: start; }
.vt-sys h3 a { color: inherit; text-decoration: none; }
.vt-sys h3 a:hover { color: var(--primary-ink); }
.vt-sys p { margin: 0; color: var(--muted); line-height: 1.6; font-size: 0.9375rem; }
@media (max-width: 760px) { .vt-systems { grid-template-columns: minmax(0, 1fr); } }

/* ---------- Survey ---------- */
.vt-survey { display: grid; grid-template-columns: minmax(0, 1fr) minmax(0, 1fr); gap: clamp(2rem, 4vw, 3.5rem); align-items: start; }
.vt-steps { list-style: none; margin: 1.5rem 0 0; padding: 0; counter-reset: s; display: grid; }
.vt-steps li { counter-increment: s; display: grid; grid-template-columns: 2.4rem 1fr; gap: 0.9rem; padding: 1rem 0; border-top: 1px solid var(--border); }
.vt-steps li::before { content: counter(s); width: 1.9rem; height: 1.9rem; border-radius: 50%; background: var(--primary); color: var(--on-primary); display: grid; place-items: center; font: 800 0.875rem/1 var(--font-heading); }
.vt-steps p { margin: 0.25rem 0 0; color: var(--muted); line-height: 1.6; font-size: 0.9375rem; }
.vt-attach { display: grid; grid-template-columns: auto 1fr; gap: 0.6rem; align-items: start; padding: 0.85rem; border: 1px dashed var(--border); border-radius: var(--radius); font-size: 0.9125rem; line-height: 1.55; cursor: pointer; }
.vt-attach input { margin-top: 0.25rem; }
.vt-ok { display: grid; grid-template-columns: auto 1fr; gap: 0.6rem; align-items: start; font: 700 1.05rem/1.35 var(--font-heading); margin: 0 0 1rem; }
.vt-ok svg { width: 1.3rem; height: 1.3rem; color: var(--primary-ink); }
.vt-receipt { list-style: none; margin: 0 0 1.25rem; padding: 0; display: grid; }
.vt-receipt li { display: grid; grid-template-columns: minmax(0, 9rem) minmax(0, 1fr); gap: 1rem; padding: 0.6rem 0; border-top: 1px solid var(--border); font-size: 0.9375rem; }
.vt-receipt li:last-child { border-bottom: 1px solid var(--border); }
.vt-receipt span:first-child { color: var(--muted); font-size: 0.875rem; }
@media (max-width: 860px) { .vt-survey { grid-template-columns: minmax(0, 1fr); } }
@media (max-width: 520px) { .vt-receipt li { grid-template-columns: minmax(0, 1fr); gap: 0.15rem; } }

/* ---------- Collection / detail ---------- */
.vt-pagehead { padding-block: clamp(2.5rem, 2rem + 3vw, 4rem); border-bottom: 1px solid var(--border); }
.vt-dhead { padding-block: clamp(2rem, 1.5rem + 2.5vw, 3.25rem); }
.vt-crumb { font-size: 0.875rem; color: var(--muted); margin: 0 0 1rem; }
.vt-crumb a { color: var(--muted); }
.vt-dgrid { display: grid; grid-template-columns: minmax(0, 1.2fr) minmax(0, 1fr); gap: clamp(1.5rem, 3vw, 2.5rem); align-items: start; margin-top: 1.75rem; }
.vt-dgrid img { width: 100%; aspect-ratio: 4 / 3; object-fit: cover; border-radius: var(--radius); }
.vt-cols { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 1rem 2rem; }
.vt-list { list-style: none; margin: 0.9rem 0 0; padding: 0; display: grid; }
.vt-list li { display: grid; grid-template-columns: auto 1fr; gap: 0.6rem; padding: 0.7rem 0; border-top: 1px solid var(--border); line-height: 1.6; }
.vt-list--yes li::before { content: "+"; font-weight: 800; color: var(--primary-ink); }
.vt-list--no li::before { content: "−"; font-weight: 800; color: var(--muted); }
.vt-list--dot li::before { content: "○"; color: var(--primary-ink); }
.vt-thumbs { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 0.75rem; margin-top: 1.1rem; }
.vt-thumb { padding: 0; border: 1px solid var(--border); border-radius: var(--radius); overflow: hidden; background: none; cursor: pointer; }
.vt-thumb img { width: 100%; aspect-ratio: 4 / 3; object-fit: cover; display: block; }
.vt-thumb:hover { border-color: var(--text); }
@media (max-width: 860px) { .vt-dgrid, .vt-cols { grid-template-columns: minmax(0, 1fr); } }
@media (max-width: 560px) { .vt-thumbs { grid-template-columns: repeat(2, minmax(0, 1fr)); } }

/* ---------- FAQ + footer ---------- */
.vt-faq details { border-top: 1px solid var(--border); }
.vt-faq details:last-of-type { border-bottom: 1px solid var(--border); }
.vt-faq summary { cursor: pointer; padding: 1.05rem 0; font: 700 1rem/1.4 var(--font-heading); list-style: none; display: grid; grid-template-columns: 1fr auto; gap: 1rem; }
.vt-faq summary::-webkit-details-marker { display: none; }
.vt-faq summary::after { content: "+"; color: var(--primary-ink); font-size: 1.25rem; line-height: 1; }
.vt-faq details[open] summary::after { content: "–"; }
.vt-faq p { margin: 0 0 1.15rem; color: var(--muted); line-height: 1.7; max-width: 46rem; }
.vt-footer { background: var(--surface-2); color: var(--on-surface-2); padding-block: clamp(2.5rem, 2rem + 3vw, 3.75rem) 2rem; }
.vt-footer__grid { display: grid; grid-template-columns: minmax(0, 1.5fr) repeat(3, minmax(0, 1fr)); gap: 2rem; }
.vt-footer .vt-logo { color: var(--on-surface-2); }
.vt-footer .vt-logo i { box-shadow: 0 0 0 3px var(--surface-2), 0 0 0 4.5px var(--primary); }
.vt-footer .vt-logo small { color: var(--primary-on-dark); }
.vt-footer p { color: var(--on-surface-2); opacity: 0.8; line-height: 1.7; font-size: 0.9rem; margin: 0.8rem 0 0; }
.vt-footer h3 { font: 700 0.75rem/1 var(--font-heading); letter-spacing: 0.12em; text-transform: uppercase; color: var(--primary-on-dark); margin: 0 0 0.9rem; }
.vt-footer ul { list-style: none; margin: 0; padding: 0; display: grid; gap: 0.55rem; }
.vt-footer a { color: var(--on-surface-2); text-decoration: none; font-size: 0.9rem; }
.vt-footer a:hover { text-decoration: underline; }
.vt-footer__note { margin-top: 2.25rem; padding-top: 1.4rem; border-top: 1px solid rgba(247,249,250,.18); font-size: 0.8125rem; line-height: 1.7; opacity: 0.75; }
.vt-footer .xy-attribution { opacity: 0.75; }
.vt-footer .xy-attribution a { text-decoration: underline; }
@media (max-width: 820px) { .vt-footer__grid { grid-template-columns: repeat(2, minmax(0, 1fr)); } }
@media (max-width: 520px) { .vt-footer__grid { grid-template-columns: minmax(0, 1fr); } }