/* 00  Core — resets and behaviour hooks only. Every visual decision for this
       site lives in the sections below, starting with the design tokens.    */

*, *::before, *::after { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body { margin: 0; }
img, svg, iframe, video { display: block; max-width: 100%; }
img { height: auto; }
iframe { border: 0; }
figure { margin: 0; }
[hidden] { display: none !important; }
:where(a, button, input, select, textarea, summary, [tabindex]):focus-visible { outline: 3px solid var(--focus); outline-offset: 3px; }
.skip-link { position: absolute; left: 0.5rem; top: 0.5rem; z-index: 999; transform: translateY(-160%); padding: 0.8rem 1.2rem; background: #000; color: #fff; font-weight: 700; text-decoration: none; }
.skip-link:focus { transform: none; }
.visually-hidden { position: absolute !important; width: 1px; height: 1px; margin: -1px; padding: 0; overflow: hidden; clip: rect(0 0 0 0); white-space: nowrap; border: 0; }
.nav-toggle .icon-close, .nav-toggle[aria-expanded="true"] .icon-open { display: none; }
.nav-toggle[aria-expanded="true"] .icon-close { display: block; }
summary { cursor: pointer; }
summary::-webkit-details-marker { display: none; }
.hp-field { position: absolute; left: -9999px; width: 1px; height: 1px; overflow: hidden; }
.field { display: flex; flex-direction: column; gap: 0.3rem; min-width: 0; }
.field__error { margin: 0; min-height: 1rem; font-size: 0.82rem; font-weight: 700; color: var(--err); }
.field.is-invalid :where(input, select, textarea) { border-color: var(--err); }
.form-status { min-height: 1.2rem; font-weight: 700; }
.form-status.is-error { color: var(--err); }
.form-status.is-ok { color: var(--ok); }
.img-placeholder { display: flex; flex-direction: column; align-items: center; justify-content: center; gap: 0.25rem; width: 100%; padding: 1rem; text-align: center; font-size: 0.72rem; letter-spacing: 0.08em; text-transform: uppercase; line-height: 1.5; }
.img-placeholder b { display: block; font-size: 0.92rem; letter-spacing: 0; text-transform: none; word-break: break-all; }
:target { scroll-margin-top: 120px; }
@media (prefers-reduced-motion: no-preference) { html { scroll-behavior: smooth; } }
@media (prefers-reduced-motion: reduce) { *, *::before, *::after { animation-duration: 0.001ms !important; transition-duration: 0.001ms !important; scroll-behavior: auto !important; } }

/* ==========================================================================
   ForgeLine HVAC Solutions — hvacforgeline.xyz
   THE DEVICE: the billet. Every block carries an asymmetric border — 8px on
   the top and left, 2px on the bottom and right — so it reads as struck steel
   rather than drawn. A solid accent square sits over the top-left corner.
   01 Tokens · 02 Base · 03 Header · 04 Phone billet · 05 Buttons
   06 Hero · 07 Page heads · 08 Billets (the device) · 09 Blocks
   10 Commissioning (signature) · 11 FAQ · 12 Form & contact · 13 Footer · 14 Images
   ========================================================================== */

/* 01 Tokens */
:root {
  --paper: #e9e9e6; --band: #d8d8d4; --white: #ffffff;
  --ink: #22252a; --ink-2: #3a3e45; --ink-l: #8b8f96;
  --fo: #ff5a1f; --fo-d: #b03c0e; --fo-l: #fdeae1;
  --text: #4a4d52; --muted: #7a7d82; --line: #c2c2be;
  --focus: #b03c0e; --err: #b03c0e;
  --disp: "Chonburi", Georgia, "Times New Roman", serif;
  --sans: system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  --f-sm: 0.93rem; --f-xs: 0.78rem; --f0: clamp(1rem, 0.96rem + 0.2vw, 1.07rem);
  --f1: clamp(1.02rem, 0.96rem + 0.3vw, 1.14rem);
  --f2: clamp(1.18rem, 1.04rem + 0.7vw, 1.55rem); --f3: clamp(1.5rem, 1.22rem + 1.45vw, 2.2rem);
  --r: 0px; --wrap: 1120px; --col: 62ch; --hd: 58px;
  --pad-y: clamp(2.5rem, 2.1rem + 2.5vw, 3.9rem);
}
@media (min-width: 900px) { :root { --hd: 66px; } }

/* 02 Base */
body { background: var(--paper); color: var(--text); font-family: var(--sans); font-size: var(--f0); line-height: 1.78; }
h1, h2, h3 { margin: 0 0 0.5em; font-family: var(--disp); color: var(--ink); font-weight: 400; line-height: 1.34; text-wrap: balance; letter-spacing: -0.01em; }
h1 { font-size: var(--f3); }
h2 { font-size: var(--f2); }
h3 { font-size: var(--f1); }
p { margin: 0 0 0.95em; }
p:last-child { margin-bottom: 0; }
a { color: var(--fo-d); text-underline-offset: 3px; }
a:hover { color: var(--ink); }
strong, b { color: var(--ink); font-weight: 700; }
ul, ol { margin: 0 0 1em; padding-left: 1.2em; }
li { margin-bottom: 0.38rem; }
.wrap { width: min(100% - 1.8rem, var(--wrap)); margin-inline: auto; }
.col { max-width: none; }
.col > * { max-width: var(--col); }
.colc { max-width: var(--col); margin-inline: auto; }
.mark { display: block; margin-bottom: 0.4rem; font-family: var(--sans); font-size: 0.68rem; font-weight: 700; letter-spacing: 0.22em; text-transform: uppercase; color: var(--fo-d); }

/* 03 Header */
.hd { position: sticky; top: 0; z-index: 40; background: var(--ink); border-bottom: 5px solid var(--fo); }
.hd__bar .wrap { display: flex; align-items: center; gap: 0.6rem; min-height: var(--hd); }
.fl-logo { display: inline-flex; align-items: center; gap: 0.55rem; margin-right: auto; color: #fff; text-decoration: none; }
.fl-logo svg { width: 28px; height: 28px; flex: none; }
.fl-logo b { display: block; color: #fff; font-family: var(--disp); font-size: 0.98rem; font-weight: 400; line-height: 1.16; }
.fl-logo small { display: block; font-size: 0.5rem; font-weight: 700; letter-spacing: 0.18em; text-transform: uppercase; color: #ffb896; }
.nav-toggle { display: inline-flex; align-items: center; justify-content: center; flex: none; width: 38px; height: 38px; padding: 0; border: 0; border-top: 4px solid var(--fo); border-left: 4px solid var(--fo); border-radius: var(--r); background: #3a3e45; color: #fff; cursor: pointer; }
.nav-toggle svg { width: 18px; height: 18px; }
.hd :focus-visible { outline-color: #ffb896; }
.flnav { display: none; }
@media (max-width: 899px) {
  .hd__bar .btn { display: none; }
  .flnav { position: absolute; top: 100%; left: 0; right: 0; flex-direction: column; padding: 0.3rem 0.9rem 1rem; background: var(--ink); border-bottom: 5px solid var(--fo); }
  .flnav.is-open { display: flex; }
  .flnav a { padding: 0.78rem 0.2rem; border-bottom: 1px solid #3a3e45; color: #fff; font-family: var(--disp); font-size: 0.98rem; text-decoration: none; }
  .flnav a[aria-current="page"] { color: #ffb896; }
}
@media (max-width: 400px) { .fl-logo small { display: none; } }
@media (min-width: 900px) {
  .nav-toggle { display: none; }
  .flnav { display: flex; gap: 1.3rem; }
  .flnav a { position: relative; padding: 0.3rem 0 0.35rem; color: #c3c6ca; font-family: var(--disp); font-size: 0.9rem; text-decoration: none; white-space: nowrap; }
  .flnav a:hover { color: #fff; }
  .flnav a[aria-current="page"] { color: #fff; }
  .flnav a[aria-current="page"]::before { content: ""; position: absolute; left: -9px; top: 0.45rem; width: 5px; height: 5px; background: var(--fo); }
}

/* 04 Phone billet */
.flph { display: grid; grid-template-columns: 1fr 1fr; background: var(--ink); gap: 4px; padding: 0 0 4px; }
.flph a { display: block; padding: 0.4rem 0.9rem 0.5rem; background: var(--white); border-top: 5px solid var(--fo); border-left: 5px solid var(--fo); color: var(--ink); font-family: var(--disp); font-size: 0.98rem; text-decoration: none; white-space: nowrap; }
.flph a + a { background: var(--fo); border-top-color: var(--ink); border-left-color: var(--ink); color: #2a1004; }
.flph .k { display: block; font-family: var(--sans); font-size: 0.55rem; font-weight: 700; letter-spacing: 0.2em; text-transform: uppercase; color: var(--muted); }
.flph a + a .k { color: #6e2e0c; }
@media (min-width: 900px) { .flph { display: none; } }

/* 05 Buttons */
.btn { display: inline-flex; align-items: center; justify-content: center; gap: 0.5rem; padding: 0.54rem 1.2rem 0.6rem; border: 0; border-top: 4px solid var(--ink); border-left: 4px solid var(--ink); border-radius: var(--r); background: var(--fo); color: #2a1004; font-family: var(--disp); font-size: 0.92rem; line-height: 1.44; text-decoration: none; white-space: nowrap; cursor: pointer; transition: background-color 0.18s, color 0.18s; }
.btn:hover { background: #e04a13; color: #2a1004; }
.btn svg { width: 1em; height: 1em; flex: none; }
.btn--ink { background: var(--ink); border-top-color: var(--fo); border-left-color: var(--fo); color: #fff; }
.btn--ink:hover { background: var(--ink-2); color: #fff; }
.btn--line { background: transparent; border-top-color: var(--ink); border-left-color: var(--ink); color: var(--ink); box-shadow: inset 0 0 0 2px var(--ink); }
.btn--line:hover { background: var(--ink); color: #fff; }
.btn--paper, .sec--ink a.btn--paper, .phead a.btn--paper, .bi--ink a.btn--paper { background: var(--paper); border-top-color: var(--fo); border-left-color: var(--fo); color: var(--ink); }
.btn--paper:hover, .sec--ink a.btn--paper:hover, .phead a.btn--paper:hover, .bi--ink a.btn--paper:hover { background: #fff; color: var(--ink); }
@media (max-width: 460px) { .btn { white-space: normal; text-align: center; } }
.btns { display: flex; flex-wrap: wrap; gap: 0.75rem; margin-top: 1.5rem; }

/* 08 The billet */
.bi { position: relative; padding: 1.35rem 1.15rem 1.3rem; background: var(--white); border: 2px solid var(--ink); border-top-width: 8px; border-left-width: 8px; }
.bi__n { position: absolute; top: -8px; left: -8px; display: inline-block; min-width: 1.9rem; padding: 0.1rem 0.45rem 0.16rem; background: var(--fo); color: #2a1004; font-family: var(--disp); font-size: 0.68rem; text-align: center; }
.bi > h2, .bi > h3, .bi > .mark { padding-left: 2.2rem; }
.bi > .mark + h2, .bi > .mark + h3 { padding-left: 0; }
.bi--fo { background: var(--fo-l); }
.bi--fo .bi__n { background: var(--ink); color: #fff; }
.bi--ink { background: var(--ink); border-color: var(--fo); color: #c3c6ca; }
.bi--ink h2, .bi--ink h3, .bi--ink b { color: #fff; }
.bi--ink .mark { color: #ffb896; }
.bi--ink a:not(.btn) { color: #fff; }
.bi--ink :focus-visible { outline-color: #ffb896; }
.bi > *:last-child { margin-bottom: 0; }
.bis { display: grid; gap: 1.3rem; }
@media (min-width: 640px) { .bis--2 { grid-template-columns: repeat(2, 1fr); } }
@media (min-width: 940px) { .bis--3 { grid-template-columns: repeat(3, 1fr); } .bis--2b { grid-template-columns: repeat(2, 1fr); gap: 1.7rem; } }
.bis > * { min-width: 0; }
.sec--ink .bi:not(.bi--ink) { color: var(--text); }
.sec--ink .bi:not(.bi--ink) a:not(.btn), .sec--ink .bi:not(.bi--ink) .mark { color: var(--fo-d); }

/* 06 Hero */
.hero { padding-block: clamp(2.4rem, 2rem + 2.5vw, 3.9rem); background: var(--band); }
.hero .lede { font-size: 1.08rem; line-height: 1.7; }
.hero__grid { display: grid; gap: 1.8rem; align-items: center; }
@media (min-width: 940px) { .hero__grid { grid-template-columns: 1.06fr 0.94fr; gap: 2.8rem; } }
.hero__grid > * { min-width: 0; }

/* 07 Page heads */
.phead { padding-block: clamp(1.9rem, 1.6rem + 1.9vw, 2.9rem); background: var(--ink); color: #c3c6ca; border-bottom: 5px solid var(--fo); }
.phead h1 { color: #fff; }
.phead .mark { color: #ffb896; }
.phead a:not(.btn) { color: #fff; }
.phead :focus-visible { outline-color: #ffb896; }
.crumbs { display: flex; flex-wrap: wrap; gap: 0.45rem; margin: 0 0 0.7rem; padding: 0; list-style: none; font-size: 0.75rem; font-weight: 700; letter-spacing: 0.05em; }
.crumbs li + li::before { content: "/"; margin-right: 0.45rem; color: var(--muted); }
.phead .crumbs li + li::before { color: #8b8f96; }

/* 09 Blocks */
.sec { padding-block: var(--pad-y); }
.sec--paper { background: var(--paper); }
.sec--white { background: var(--white); }
.sec--band { background: var(--band); }
.sec--ink { background: var(--ink); color: #c3c6ca; }
.sec--ink h2, .sec--ink h3, .sec--ink b { color: #fff; }
.sec--ink .mark { color: #ffb896; }
.sec--ink a:not(.btn) { color: #fff; }
.sec--ink :focus-visible { outline-color: #ffb896; }
.head { max-width: var(--col); margin-bottom: 1.8rem; }
.tbl { width: 100%; border-collapse: collapse; font-size: var(--f-sm); text-align: left; }
.tbl th, .tbl td { padding: 0.62rem 0.7rem; vertical-align: top; border-bottom: 1px solid var(--line); }
.tbl th { font-size: 0.71rem; font-weight: 700; letter-spacing: 0.11em; text-transform: uppercase; color: var(--muted); }
.tbl td:first-child { font-weight: 700; color: var(--ink); }
.sec--ink .tbl th, .sec--ink .tbl td { border-bottom-color: #3a3e45; }
.sec--ink .tbl td:first-child { color: #fff; }
.scroll { overflow-x: auto; }
.figwide img, .figwide .img-placeholder { width: 100%; aspect-ratio: 16 / 9; object-fit: cover; }
.figbox img, .figbox .img-placeholder { width: 100%; aspect-ratio: 4 / 3; object-fit: cover; }
.fig-bi { border: 2px solid var(--ink); border-top-width: 8px; border-left-width: 8px; }
.fig-bi img, .fig-bi .img-placeholder { display: block; }
.map { display: block; width: 100%; height: clamp(300px, 34vw, 380px); background: var(--band); }
.where { display: grid; gap: 2rem; align-items: center; }
@media (min-width: 880px) { .where { grid-template-columns: 1fr 1fr; gap: 2.8rem; } }
.where > * { min-width: 0; }

/* 10 Commissioning (signature) */
.cm2 { display: grid; gap: 1.4rem; }
@media (min-width: 1000px) { .cm2 { grid-template-columns: 0.84fr 1.16fr; gap: 2rem; align-items: start; } .cm2__set { position: sticky; top: calc(var(--hd) + 1rem); } }
.cm2__set fieldset { margin: 0 0 1.2rem; padding: 0; border: 0; }
.cm2__set fieldset:last-of-type { margin-bottom: 0; }
.cm2__set legend { display: block; margin-bottom: 0.5rem; padding: 0; font-family: var(--disp); font-size: 0.98rem; color: var(--ink); }
.opts { display: grid; gap: 0.3rem; }
.opts label { position: relative; display: block; }
.opts input { position: absolute; opacity: 0; }
.opts span { display: block; padding: 0.5rem 0.75rem; border: 1px solid var(--line); border-radius: var(--r); background: var(--paper); font-size: var(--f-sm); cursor: pointer; }
.opts input:checked + span { background: var(--ink); border-color: var(--ink); color: #fff; }
.opts input:focus-visible + span { outline: 3px solid var(--focus); outline-offset: 2px; }
.cm2__out { min-width: 0; display: grid; gap: 1.3rem; align-content: start; }
.cm2__flag { position: relative; padding: 1.35rem 1.15rem 1.3rem; background: var(--fo); color: #2a1004; border: 2px solid var(--ink); border-top-width: 8px; border-left-width: 8px; }
.cm2__flag .bi__n { background: var(--ink); color: #fff; }
.cm2__flag b { display: block; margin-bottom: 0.2rem; padding-left: 2.2rem; color: #2a1004; }
.cm2__flag p { font-size: var(--f-sm); }
.cm2__out h2 { font-size: var(--f1); }
.cm2__out .bi p, .cm2__out .bi ul { font-size: var(--f-sm); }

/* 11 FAQ */
.faq { display: grid; gap: 0.7rem; max-width: 860px; margin-top: 1.4rem; }
.flq { background: var(--white); border: 2px solid var(--ink); border-top-width: 6px; border-left-width: 6px; }
.flq summary { display: flex; justify-content: space-between; gap: 1rem; padding: 0.82rem 1.1rem 0.88rem; font-family: var(--disp); font-size: 0.96rem; line-height: 1.5; color: var(--ink); list-style: none; cursor: pointer; }
.flq summary::after { content: "+"; flex: none; font-family: var(--sans); color: var(--fo-d); }
.flq[open] { border-top-color: var(--fo); border-left-color: var(--fo); }
.flq[open] summary::after { content: "\2013"; }
.flq[open] summary { color: var(--fo-d); }
.flq > div { padding: 0 1.1rem 1.15rem; }

/* 12 Form & contact */
.form { display: grid; gap: 1rem 1.3rem; margin-top: 1.2rem; }
@media (min-width: 640px) { .form--2col { grid-template-columns: 1fr 1fr; } }
.field--full, .form__end { grid-column: 1 / -1; }
.field label, .picks legend { font-weight: 700; color: var(--ink); font-size: 0.93rem; }
.req { color: var(--err); }
.opt { font-weight: 400; color: var(--muted); }
input[type="text"], input[type="tel"], input[type="email"], input[type="number"], select, textarea { width: 100%; padding: 0.72rem 0.9rem; font: inherit; color: var(--ink); background: var(--white); border: 1px solid #a9a9a5; border-radius: var(--r); }
select { appearance: none; background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24' fill='none' stroke='%2322252a' stroke-width='2.6'%3E%3Cpath d='m6 9 6 6 6-6'/%3E%3C/svg%3E"); background-repeat: no-repeat; background-position: right 0.85rem center; background-size: 15px; padding-right: 2.3rem; }
textarea { min-height: 140px; resize: vertical; }
input:focus, select:focus, textarea:focus { border-color: var(--ink); }
.picks { margin: 0; padding: 0; border: 0; display: flex; flex-direction: row; flex-wrap: wrap; gap: 0.4rem; }
.picks legend { margin-bottom: 0.45rem; padding: 0; }
.pick { position: relative; }
.pick input { position: absolute; opacity: 0; }
.pick span { display: inline-block; padding: 0.42rem 0.9rem; border: 1px solid #a9a9a5; border-radius: var(--r); background: var(--white); font-size: var(--f-sm); cursor: pointer; }
.pick input:checked + span { background: var(--ink); border-color: var(--ink); color: #fff; }
.pick input:focus-visible + span { outline: 3px solid var(--focus); outline-offset: 2px; }
.form-note { margin: 0.5rem 0 0; font-size: 0.84rem; color: var(--muted); }
.contact { display: grid; gap: 1.8rem; align-items: start; }
@media (min-width: 920px) { .contact { grid-template-columns: 1.1fr 0.9fr; gap: 2.4rem; } }
.contact > * { min-width: 0; }
.side { display: grid; gap: 1.3rem; }

/* 13 Footer */
.ft { background: var(--ink); color: #9a9da2; font-size: var(--f-sm); border-top: 5px solid var(--fo); }
.ft a { color: #fff; }
.ft :focus-visible { outline-color: #ffb896; }
.ft__row { display: grid; gap: 1.5rem; padding-block: 2.6rem 1.6rem; }
@media (min-width: 820px) { .ft__row { grid-template-columns: 1.5fr 1fr 1fr; } }
.ft__name { margin: 0 0 0.45rem; font-family: var(--disp); font-size: 0.98rem; color: #fff; }
.ft h2 { margin: 0 0 0.55rem; font-family: var(--sans); font-size: 0.7rem; letter-spacing: 0.19em; text-transform: uppercase; color: #ffb896; }
.ft ul { margin: 0; padding: 0; list-style: none; display: grid; gap: 0.32rem; }
.ft__base { padding-block: 0.9rem; border-top: 1px solid #3a3e45; font-size: 0.8rem; }

/* 14 Images */
.img-placeholder { background: var(--band); border: 0; color: var(--muted); }
.img-placeholder b { color: var(--ink); overflow-wrap: anywhere; }