/* Input n Output · IA/O Modular Analog v1 */
:root {
  --ink: #14110E;
  --paper: #ECE8DF;
  --card: #F5F2EB;
  --signal: #FF5722;
  --amber: #FFB000;
  --red: #E63946;
  --data: #2D3E50;
  --line: rgba(20, 17, 14, .16);
  --cn: "PingFang SC", "Hiragino Sans GB", "Noto Sans SC", "Microsoft YaHei", sans-serif;
  --f-heavy: "Archivo Black", "Space Grotesk", system-ui, var(--cn);
  --f-head: "Space Grotesk", system-ui, var(--cn);
  --f-body: "Inter", system-ui, -apple-system, var(--cn);
  --f-mono: "JetBrains Mono", ui-monospace, Menlo, monospace, var(--cn);
  --shadow: 4px 4px 0 var(--ink);
}

*, *::before, *::after { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; scroll-behavior: smooth; }
body {
  margin: 0;
  background: var(--paper);
  color: var(--ink);
  font: 400 16px/1.6 var(--f-body);
  -webkit-font-smoothing: antialiased;
}
body::before {
  content: "";
  position: fixed; inset: 0; z-index: 50; pointer-events: none;
  opacity: .07; mix-blend-mode: multiply;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='160' height='160'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='.9' numOctaves='2' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23n)'/%3E%3C/svg%3E");
}
img { display: block; max-width: 100%; height: auto; }
[hidden] { display: none !important; }
a { color: inherit; }
h1, h2, h3 { margin: 0; text-wrap: balance; }
p { margin: 0; }

/* language toggle */
.zh { display: none; }
html[data-lang="zh"] .zh { display: revert; }
html[data-lang="zh"] .en { display: none; }

.skip { position: absolute; left: -999px; top: 8px; background: var(--ink); color: var(--paper); padding: 8px 12px; z-index: 99; }
.skip:focus { left: 8px; }
:focus-visible { outline: 3px solid var(--data); outline-offset: 2px; }

.wrap { width: 100%; max-width: 1120px; margin: 0 auto; padding: 0 20px; }

.strip, .kicker, .card-strip, .tags, .price small, .stamp, .btn, .lang, .top-link, .unit figcaption, .board, .lbl, .chips, .form-note, .alt, .fine {
  font-family: var(--f-mono);
}
.strip { font-size: 11px; letter-spacing: 2px; text-transform: uppercase; font-weight: 500; }

/* header */
.top {
  position: sticky; top: 0; z-index: 20;
  display: flex; align-items: center; justify-content: space-between; gap: 12px;
  padding: 12px 20px;
  background: rgba(236, 232, 223, .92);
  backdrop-filter: blur(8px); -webkit-backdrop-filter: blur(8px);
  border-bottom: 2px solid var(--ink);
}
.brand { display: flex; align-items: center; gap: 10px; text-decoration: none; }
.brand-mark, .foot-mark {
  font-family: var(--f-heavy); font-size: 18px; letter-spacing: .5px; line-height: 1;
  background: var(--ink); color: var(--paper); padding: 6px 8px 5px;
}
.brand-mark i, .foot-mark i { font-style: normal; color: var(--signal); }
.brand-name { font-family: var(--f-head); font-weight: 700; font-size: 16px; white-space: nowrap; }
.top-nav { display: flex; align-items: center; gap: 8px; }
.top-link { font-size: 12px; letter-spacing: 1px; text-transform: uppercase; text-decoration: none; padding: 8px 6px; }
.top-link:hover { text-decoration: underline; }
.lang {
  font-size: 13px; font-weight: 700; min-width: 52px; min-height: 36px;
  background: var(--card); color: var(--ink);
  border: 2px solid var(--ink); box-shadow: 2px 2px 0 var(--ink); cursor: pointer;
}
.lang:active { transform: translate(2px, 2px); box-shadow: none; }

/* buttons */
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 10px;
  min-height: 52px; padding: 14px 22px;
  font-size: 14px; font-weight: 700; letter-spacing: 1.5px; text-transform: uppercase; text-decoration: none;
  border: 2px solid var(--ink); box-shadow: var(--shadow); cursor: pointer; white-space: nowrap;
  transition: transform .08s, box-shadow .08s;
}
.btn:active { transform: translate(4px, 4px); box-shadow: none; }
.btn-main { background: var(--signal); color: var(--ink); }
.btn-main:hover { box-shadow: 6px 6px 0 var(--ink); transform: translate(-1px, -1px); }
.btn[disabled] { opacity: .6; cursor: progress; }
.btn-link {
  display: inline-flex; flex-wrap: wrap; align-items: baseline; gap: 2px 8px;
  font-family: var(--f-head); font-weight: 700; font-size: 16px; text-decoration: none;
}
.btn-link > .en, .btn-link > .zh { text-decoration: underline; text-decoration-thickness: 2px; text-underline-offset: 4px; }
.btn-link small { display: inline-block; font-family: var(--f-mono); font-weight: 500; font-size: 12px; text-decoration: none; opacity: .65; }

/* hero */
.hero { display: grid; gap: 36px; padding-top: 32px; padding-bottom: 48px; }
.hero-tape { margin: 18px 0 20px; }
main section { scroll-margin-top: 68px; }
.tape {
  display: inline-block; transform: rotate(-2deg);
  background: var(--signal); color: var(--ink);
  font-family: var(--f-heavy); font-size: clamp(22px, 6vw, 30px); line-height: 1.1;
  padding: 8px 14px 7px;
  box-shadow: 3px 3px 0 rgba(20, 17, 14, .22);
}
.hero h1 {
  font-family: var(--f-head); font-weight: 700;
  font-size: clamp(36px, 10.4vw, 72px); line-height: 1.02; letter-spacing: -.02em;
}
html[data-lang="zh"] .hero h1 { line-height: 1.15; letter-spacing: 0; }
.lede { margin-top: 18px; font-size: 17px; max-width: 34em; color: #2a2520; }
.hero-cta { display: flex; flex-direction: column; align-items: flex-start; gap: 20px; margin-top: 28px; }

.unit { margin: 0; justify-self: center; width: min(100%, 440px); transform: rotate(1.5deg); }
.unit picture { display: block; border: 2px solid var(--ink); box-shadow: 8px 8px 0 var(--ink); background: #e9281e; }
.unit figcaption {
  display: flex; justify-content: space-between; gap: 12px;
  margin-top: 14px; font-size: 11px; letter-spacing: 2px; font-weight: 500;
}
.dot::before { content: ""; display: inline-block; width: 7px; height: 7px; border-radius: 50%; background: var(--amber); margin-right: 7px; vertical-align: 1px; box-shadow: 0 0 6px var(--amber); }

/* sections */
.block { padding-top: 56px; padding-bottom: 56px; border-top: 2px solid var(--ink); }
.kicker { font-size: 12px; letter-spacing: 2px; text-transform: uppercase; font-weight: 500; display: flex; align-items: center; gap: 10px; }
.kicker b { background: var(--ink); color: var(--paper); padding: 3px 7px; font-weight: 700; letter-spacing: 1px; }
.block h2 {
  margin-top: 14px; max-width: 18em;
  font-family: var(--f-head); font-weight: 700;
  font-size: clamp(28px, 7vw, 46px); line-height: 1.08; letter-spacing: -.015em;
}
html[data-lang="zh"] .block h2 { line-height: 1.25; letter-spacing: 0; }

/* service cards */
.cards { display: grid; gap: 20px; margin-top: 32px; }
.card { background: var(--card); border: 2px solid var(--ink); box-shadow: var(--shadow); padding: 0 20px 22px; }
.card-strip {
  display: flex; justify-content: space-between; gap: 12px;
  margin: 0 -20px 18px; padding: 8px 20px;
  border-bottom: 2px solid var(--ink);
  font-size: 10.5px; letter-spacing: 1.5px; text-transform: uppercase; font-weight: 500;
}
.card-strip span:first-child { font-weight: 700; white-space: nowrap; }
.card-strip span:last-child { text-align: right; opacity: .7; }
.card h3 { font-family: var(--f-heavy); font-size: 30px; line-height: 1.05; font-weight: 400; display: flex; flex-wrap: wrap; align-items: baseline; gap: 4px 12px; }
.card h3 .cn { font-family: var(--cn); font-weight: 700; font-size: 18px; opacity: .55; }
.card p { margin-top: 10px; color: #2a2520; }
.tags { list-style: none; padding: 0; margin: 16px 0 0; display: flex; flex-wrap: wrap; gap: 6px; font-size: 11px; letter-spacing: .5px; }
.tags li { border: 1.5px solid var(--ink); padding: 2px 8px; border-radius: 99px; }
.card-soon { background: transparent; border-style: dashed; box-shadow: none; }
.card-soon .card-strip { border-bottom-style: dashed; }
.soon { background: var(--ink); color: var(--paper); padding: 1px 6px; opacity: 1 !important; }

/* proof board */
.board {
  position: relative; overflow: hidden;
  background: var(--ink); color: var(--amber);
  padding: 26px 22px; box-shadow: 6px 6px 0 rgba(20, 17, 14, .25);
}
.board::after { content: ""; position: absolute; inset: 0; pointer-events: none; background: repeating-linear-gradient(0deg, transparent 0 2px, rgba(0, 0, 0, .28) 2px 3px); }
.board-head { font-size: 13px; letter-spacing: 2px; font-weight: 700; }
.blink { animation: blink 1s steps(2) infinite; }
@keyframes blink { 50% { opacity: 0; } }
.board-intro { margin-top: 16px; color: var(--paper); font-family: var(--f-head); font-weight: 700; font-size: clamp(22px, 5.6vw, 32px); line-height: 1.15; }
.board-list { list-style: none; padding: 0; margin: 20px 0 0; }
.board-list li { display: flex; align-items: center; gap: 12px; padding: 12px 0; border-top: 1px dashed rgba(255, 176, 0, .35); font-size: 15px; font-weight: 500; }
.board-list em { margin-left: auto; font-style: normal; font-size: 11px; letter-spacing: 2px; border: 1px solid var(--amber); padding: 1px 6px; }
.led { width: 9px; height: 9px; border-radius: 50%; background: var(--amber); box-shadow: 0 0 8px var(--amber); flex: none; }
.board-foot { margin-top: 14px; font-size: 11px; letter-spacing: 1px; opacity: .7; }

/* steps */
.steps { list-style: none; padding: 0; margin: 32px 0 0; display: grid; gap: 0; }
.steps li { display: grid; grid-template-columns: 64px 1fr; gap: 14px; padding: 18px 0; border-top: 1.5px solid var(--line); }
.steps li:first-child { border-top: 0; }
.steps b { font-family: var(--f-heavy); font-weight: 400; font-size: 40px; line-height: .9; }
.steps h3 { font-family: var(--f-head); font-weight: 700; font-size: 20px; line-height: 1.2; }
.steps p { margin-top: 4px; color: #2a2520; }

/* pricing receipt */
.receipt { position: relative; margin-top: 32px; background: var(--card); border: 2px solid var(--ink); box-shadow: var(--shadow); padding: 8px 20px 20px; }
.stamp {
  position: absolute; top: -14px; right: 14px; transform: rotate(6deg);
  font-size: 12px; font-weight: 700; letter-spacing: 3px; color: var(--red);
  border: 2px solid var(--red); padding: 4px 10px; background: var(--paper);
}
.row { display: grid; gap: 6px; padding: 18px 0; border-bottom: 1.5px dashed var(--line); }
.row h3 { font-family: var(--f-head); font-weight: 700; font-size: 19px; }
.row p { font-size: 14.5px; color: #3a342d; margin-top: 2px; }
.row .price { font-family: var(--f-heavy); font-size: clamp(26px, 7vw, 34px); line-height: 1.1; color: var(--ink); white-space: nowrap; margin-top: 6px; }
.row-soon .price { font-size: clamp(22px, 6vw, 28px); }
.price small { font-size: 12px; font-weight: 500; letter-spacing: 1px; text-transform: uppercase; margin-right: 2px; vertical-align: 4px; }
.price small:last-child { margin: 0 0 0 4px; }
.row-soon { opacity: .6; }
.fine { margin-top: 16px; font-size: 12px; letter-spacing: .3px; line-height: 1.6; }

/* form */
.form-wrap { margin-top: 28px; max-width: 640px; }
.form { background: var(--card); border: 2px solid var(--ink); box-shadow: 6px 6px 0 var(--ink); padding: 22px 20px; display: grid; gap: 18px; }
.field { display: grid; gap: 8px; border: 0; margin: 0; padding: 0; min-width: 0; }
.lbl { font-size: 12px; letter-spacing: 1.5px; text-transform: uppercase; font-weight: 700; padding: 0; }
input, select, textarea {
  width: 100%; font: 16px/1.4 var(--f-body); color: var(--ink);
  background: var(--paper); border: 2px solid var(--ink); border-radius: 0;
  padding: 12px; min-height: 48px; -webkit-appearance: none; appearance: none;
}
select { background-image: linear-gradient(45deg, transparent 50%, var(--ink) 50%), linear-gradient(135deg, var(--ink) 50%, transparent 50%); background-position: calc(100% - 18px) 21px, calc(100% - 13px) 21px; background-size: 5px 5px; background-repeat: no-repeat; padding-right: 36px; }
textarea { resize: vertical; margin-top: 6px; }
input::placeholder, textarea::placeholder { color: #8a8278; }
input:focus, select:focus, textarea:focus { outline: none; box-shadow: 3px 3px 0 var(--data); border-color: var(--data); }
.chips { display: flex; flex-wrap: wrap; gap: 8px; }
.chips label { position: relative; cursor: pointer; }
.chips input { position: absolute; opacity: 0; width: 1px; height: 1px; min-height: 0; }
.chips label > span { display: inline-block; font-size: 13px; padding: 9px 12px; border: 2px solid var(--ink); background: var(--paper); user-select: none; }
.chips input:checked + span { background: var(--ink); color: var(--paper); }
.chips input:focus-visible + span { outline: 3px solid var(--data); outline-offset: 2px; }
.hp { position: absolute; left: -9999px; width: 1px; height: 1px; overflow: hidden; }
.form .btn { width: 100%; }
.form-note { font-size: 11px; letter-spacing: .5px; opacity: .7; text-align: center; }
.form-msg { font-size: 14px; font-weight: 600; min-height: 0; }
.form-msg:empty { display: none; }
.form-msg.err { color: var(--red); }
.form-done { background: var(--card); border: 2px solid var(--ink); box-shadow: 6px 6px 0 var(--ink); padding: 22px 20px; text-align: center; }
.form-done:focus { outline: none; }
.form-done img { width: 160px; margin: 0 auto 12px; border: 2px solid var(--ink); }
.done-title { font-family: var(--f-heavy); font-size: 32px; }
.alt { margin-top: 22px; font-size: 13px; line-height: 1.7; }
.alt a { font-weight: 700; }

/* reel */
.reel {
  display: grid; grid-auto-flow: column; grid-auto-columns: 62%; gap: 14px;
  margin: 28px -20px 24px; padding: 0 20px 14px;
  overflow-x: auto; scroll-snap-type: x mandatory; scroll-padding-inline: 20px; -webkit-overflow-scrolling: touch;
}
.reel a { scroll-snap-align: start; border: 2px solid var(--ink); box-shadow: var(--shadow); background: #d9d2c4; }

/* footer */
.foot { border-top: 2px solid var(--ink); padding: 32px 0 calc(32px + env(safe-area-inset-bottom)); }
.foot-in { display: grid; gap: 12px; justify-items: start; font-size: 14px; }
.foot .strip a { text-decoration: underline; }

@media (min-width: 720px) {
  .wrap { padding: 0 32px; }
  .top { padding: 14px 32px; }
  .cards { grid-template-columns: 1fr 1fr; gap: 24px; }
  .steps { grid-template-columns: repeat(4, 1fr); gap: 24px; }
  .steps li { grid-template-columns: 1fr; border-top: 2px solid var(--ink); padding-top: 18px; }
  .steps li:first-child { border-top: 2px solid var(--ink); }
  .row { grid-template-columns: 1fr auto; align-items: center; gap: 24px; }
  .receipt { padding: 10px 32px 24px; }
  .form { padding: 30px 28px; grid-template-columns: 1fr 1fr; column-gap: 20px; }
  .form > fieldset, .form > .btn, .form-note, .form-msg { grid-column: 1 / -1; }
  .reel { grid-auto-columns: calc((100% - 42px) / 4); margin: 28px 0 24px; padding: 0 0 14px; overflow: visible; }
  .board { padding: 34px 36px; }
  .foot-in { grid-template-columns: auto 1fr auto; align-items: center; gap: 20px; }
}
@media (min-width: 1000px) {
  .hero { grid-template-columns: 1.15fr .85fr; align-items: center; gap: 56px; padding-top: 64px; padding-bottom: 80px; }
  .cards { grid-template-columns: repeat(3, 1fr); }
  .card-soon { grid-column: 1 / -1; display: grid; grid-template-columns: 1fr 2fr; column-gap: 32px; align-items: baseline; }
  .card-soon .card-strip { grid-column: 1 / -1; }
  #talk { display: grid; grid-template-columns: .9fr 1.1fr; column-gap: 56px; align-items: start; }
  #talk .kicker, #talk h2 { grid-column: 1; }
  #talk h2 { font-size: 44px; }
  #talk .form-wrap { grid-column: 2; grid-row: 1 / span 3; margin-top: 0; }
  .block { padding-top: 80px; padding-bottom: 80px; }
}
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  .blink { animation: none; }
  .btn, .lang { transition: none; }
}