/* RF-FIELDWORK v3 — bench-instrument design system
   chassis (light panel) + glass (dark display) + VNA trace colours */

@font-face{font-family:"Archivo";font-style:normal;font-display:swap;font-weight:100 900;font-stretch:62% 125%;src:url(fonts/archivo-latin-standard-normal.woff2) format("woff2-variations");unicode-range:U+0000-00FF,U+0131,U+0152-0153,U+02BB-02BC,U+02C6,U+02DA,U+02DC,U+0304,U+0308,U+0329,U+2000-206F,U+20AC,U+2122,U+2191,U+2193,U+2212,U+2215,U+FEFF,U+FFFD}
@font-face{font-family:"Archivo";font-style:normal;font-display:swap;font-weight:100 900;font-stretch:62% 125%;src:url(fonts/archivo-latin-ext-standard-normal.woff2) format("woff2-variations");unicode-range:U+0100-02BA,U+02BD-02C5,U+02C7-02CC,U+02CE-02D7,U+02DD-02FF,U+0304,U+0308,U+0329,U+1D00-1DBF,U+1E00-1E9F,U+1EF2-1EFF,U+2020,U+20A0-20AB,U+20AD-20C0,U+2113,U+2C60-2C7F,U+A720-A7FF}

:root{
  --chassis:#C9CBC4; --chassis-hi:#DADBD5; --chassis-lo:#B6B8B0; --groove:#A3A59D; --lip:#E6E7E1;
  --ink:#15171A; --ink-2:#43463F; --ink-3:#62655D;
  --bezel:#232523; --glass:#090B0A; --glass-2:#111412; --grid:rgba(160,185,170,.13); --glass-ink:#D5DDD7; --glass-dim:#7F8A83;
  --tr1:#F2C230; --tr2:#33D1DE; --tr3:#EC5AA5; --tr4:#93D65E; --tr5:#FF7A3D; /* --tr5 = key colour of channel "Tr4" Crescendo; --tr4 green stays the status colour */
  --tr:var(--tr1);
  --sans:"Archivo","Noto SC","PingFang SC","Microsoft YaHei","Noto Sans CJK SC",system-ui,sans-serif;
  --r-panel:14px; --r-glass:10px; --r-key:7px; --r-tag:3px;
  --wrap:1240px; --gut:clamp(18px,4vw,48px);
  color-scheme:light;
}
*{box-sizing:border-box}
html{-webkit-text-size-adjust:100%;scroll-behavior:smooth}
@media (prefers-reduced-motion:reduce){html{scroll-behavior:auto}*,*::before,*::after{animation-duration:.01ms!important;animation-iteration-count:1!important;transition-duration:.01ms!important}}
body{margin:0;background:var(--chassis);color:var(--ink);font:400 16px/1.7 var(--sans);font-feature-settings:"tnum" 1;text-rendering:optimizeLegibility;-webkit-font-smoothing:antialiased}
img,video,canvas{display:block;max-width:100%}
[hidden]{display:none!important}
a{color:inherit}
button{font:inherit;color:inherit}
:focus-visible{outline:2px solid var(--ink);outline-offset:3px;border-radius:4px}
.glass :focus-visible,.on-glass :focus-visible{outline-color:var(--tr)}
::selection{background:var(--tr);color:var(--ink)}

/* ---------- language ---------- */
html[data-lang="zh"] [lang="en"]:not(html),html[data-lang="en"] [lang="zh-CN"]:not(html){display:none!important}
html[data-lang="en"] body{line-height:1.6}

/* ---------- layout ---------- */
.wrap{width:min(100% - 2*var(--gut),var(--wrap));margin-inline:auto}
.skip{position:absolute;left:-9999px;top:8px;z-index:99;background:var(--ink);color:var(--chassis);padding:8px 14px;border-radius:var(--r-key)}
.skip:focus{left:12px}
section{scroll-margin-top:80px}
.seam{height:0;border-top:1px solid var(--groove);border-bottom:1px solid var(--lip);margin:0}

/* ---------- silkscreen type ---------- */
.silk{font:600 13px/1.3 var(--sans);font-stretch:78%;letter-spacing:.01em;color:var(--ink-2)}
.silk b{color:var(--ink);font-weight:750}
h1,h2,h3{margin:0;color:var(--ink);font-weight:820;letter-spacing:-.01em}
h1{font-size:clamp(40px,6.6vw,96px);line-height:1.04;font-stretch:118%}
h2{font-size:clamp(30px,4.2vw,58px);line-height:1.1;font-stretch:112%}
h3{font-size:clamp(20px,2vw,26px);line-height:1.25;font-stretch:105%;font-weight:760}
html[data-lang="en"] h1{letter-spacing:-.025em}
html[data-lang="en"] h2{letter-spacing:-.02em}
.lead{font-size:clamp(17px,1.5vw,20px);line-height:1.75;color:var(--ink-2);max-width:40em;margin:0}
p{margin:0 0 1em}
.muted{color:var(--ink-3)}
.num{font-stretch:92%;font-weight:700;font-variant-numeric:tabular-nums}

/* ---------- top bar ---------- */
.bar{position:sticky;top:0;z-index:40;background:color-mix(in srgb,var(--chassis) 88%,transparent);backdrop-filter:blur(10px);-webkit-backdrop-filter:blur(10px);border-bottom:1px solid var(--groove);box-shadow:0 1px 0 var(--lip)}
.bar .wrap{display:flex;align-items:center;gap:28px;min-height:64px}
.brand{display:flex;align-items:center;gap:12px;text-decoration:none;white-space:nowrap}
.brand-mark{width:30px;height:30px;flex:none}
.brand-name{font:850 17px/1 var(--sans);font-stretch:125%;letter-spacing:.02em}
.brand-sub{font:600 12px/1 var(--sans);font-stretch:80%;color:var(--ink-3);margin-top:4px}
.bar nav{display:flex;gap:4px;margin-left:auto}
.bar nav a{text-decoration:none;font:600 14px/1 var(--sans);font-stretch:88%;padding:10px 12px;border-radius:var(--r-key);color:var(--ink-2)}
.bar nav a:hover{background:var(--chassis-hi);color:var(--ink)}
.crumb{display:flex;align-items:center;gap:10px;text-decoration:none;font:650 13px/1 var(--sans);font-stretch:82%;color:var(--ink-2)}
.crumb:hover{color:var(--ink)}
.crumb .brand-mark{width:22px;height:22px}
.crumb-sep{width:1px;height:22px;background:var(--groove)}
.prod-name{display:flex;align-items:center;gap:10px;font:850 16px/1 var(--sans);font-stretch:118%;text-decoration:none}
.prod-name i{width:10px;height:10px;border-radius:50%;background:var(--tr);box-shadow:0 0 0 2px var(--ink),0 0 10px var(--tr)}

/* language switch: a two-position slide switch */
.lang{display:inline-grid;grid-template-columns:1fr 1fr;background:var(--chassis-lo);border-radius:999px;padding:3px;box-shadow:inset 0 1px 2px rgba(0,0,0,.25),0 1px 0 var(--lip);flex:none}
.lang button{border:0;background:transparent;font:700 12px/1 var(--sans);font-stretch:85%;padding:7px 11px;border-radius:999px;cursor:pointer;color:var(--ink-3)}
.lang button[aria-pressed="true"]{background:var(--chassis-hi);color:var(--ink);box-shadow:0 1px 0 #fff8 inset,0 1px 3px rgba(0,0,0,.25)}
.menu-btn{display:none}

/* ---------- physical controls ---------- */
.btn{display:inline-flex;align-items:center;gap:10px;min-height:48px;padding:0 22px;border-radius:var(--r-key);font:700 15px/1 var(--sans);font-stretch:92%;text-decoration:none;cursor:pointer;border:0;transition:transform .08s,box-shadow .08s}
.btn-ink{background:var(--ink);color:var(--chassis-hi);box-shadow:0 3px 0 #000,0 6px 14px rgba(0,0,0,.22)}
.btn-ink:hover{background:#25282c}
.btn-ink:active{transform:translateY(2px);box-shadow:0 1px 0 #000,0 2px 6px rgba(0,0,0,.2)}
.btn-key{background:var(--chassis-hi);color:var(--ink);box-shadow:0 3px 0 var(--groove),0 5px 10px rgba(0,0,0,.12),inset 0 1px 0 #fff9}
.btn-key:hover{background:#e3e4de}
.btn-key:active{transform:translateY(2px);box-shadow:0 1px 0 var(--groove),inset 0 1px 0 #fff9}
.btn .led{width:8px;height:8px;border-radius:50%;background:var(--tr);box-shadow:0 0 8px var(--tr)}
.btn-row{display:flex;flex-wrap:wrap;gap:14px;align-items:center}
.link{font-weight:700;text-decoration:none;border-bottom:2px solid var(--tr);padding-bottom:2px}
.link:hover{background:color-mix(in srgb,var(--tr) 30%,transparent)}

.tag{display:inline-flex;align-items:center;gap:6px;padding:4px 8px 4px 7px;border-radius:var(--r-tag);background:var(--tr);color:var(--ink);font:800 12px/1 var(--sans);font-stretch:80%;letter-spacing:.02em;white-space:nowrap}
.tag.out{background:transparent;color:var(--tr);box-shadow:inset 0 0 0 1.5px var(--tr)}

/* ---------- glass display ---------- */
.glass{position:relative;background:var(--bezel);border-radius:calc(var(--r-glass) + 8px);padding:10px;box-shadow:0 1px 0 var(--lip),0 -1px 0 var(--groove),0 24px 50px -24px rgba(0,0,0,.55),inset 0 1px 0 #ffffff14}
.glass-in{position:relative;background:var(--glass);border-radius:var(--r-glass);overflow:hidden;box-shadow:inset 0 0 0 1px #000,inset 0 0 40px rgba(0,0,0,.8);color:var(--glass-ink)}
.glass-in::after{content:"";position:absolute;inset:0;pointer-events:none;background:linear-gradient(160deg,#ffffff0d 0%,transparent 35%);border-radius:inherit}
.gridded{background-image:linear-gradient(var(--grid) 1px,transparent 1px),linear-gradient(90deg,var(--grid) 1px,transparent 1px);background-size:10% 12.5%;background-position:-1px -1px}
.glass-head,.glass-foot{position:absolute;left:0;right:0;display:flex;align-items:center;gap:10px;padding:12px 14px;z-index:2;font:600 12px/1.2 var(--sans);font-stretch:82%;color:var(--glass-dim);pointer-events:none}
.glass-head{top:0}.glass-foot{bottom:0}
.glass-head .sp,.glass-foot .sp{margin-left:auto}
.readout{color:var(--glass-ink);font:700 13px/1.25 var(--sans);font-stretch:90%;text-align:right}
.readout small{display:block;color:var(--glass-dim);font-weight:600;font-size:11px}
.glass img.shot{width:100%;height:100%;object-fit:contain}

/* ---------- datasheet ---------- */
.spec{display:grid;grid-template-columns:minmax(90px,auto) 1fr;margin:0;border-top:1px solid var(--groove)}
.spec dt,.spec dd{margin:0;padding:11px 0;border-bottom:1px solid var(--groove);font-size:15px;line-height:1.5}
.spec dt{font:650 13px/1.5 var(--sans);font-stretch:80%;color:var(--ink-3);padding-right:18px;padding-top:12px}
.spec dd{color:var(--ink)}

/* readout tiles — real numbers only */
.meters{display:grid;grid-template-columns:repeat(auto-fit,minmax(170px,1fr));gap:2px;background:var(--groove);border:1px solid var(--groove);border-radius:var(--r-key);overflow:hidden}
.meter{background:var(--chassis-hi);padding:16px 18px 14px}
.meter .v{font:800 clamp(26px,2.6vw,36px)/1 var(--sans);font-stretch:96%;font-variant-numeric:tabular-nums;letter-spacing:-.01em}
.meter .v small{font-size:.5em;font-weight:700;margin-left:3px;color:var(--ink-2)}
.meter .k{margin-top:8px;font:600 13px/1.4 var(--sans);font-stretch:85%;color:var(--ink-2)}

/* ---------- panels ---------- */
.panel{background:var(--chassis-hi);border-radius:var(--r-panel);box-shadow:0 1px 0 #fff8 inset,0 0 0 1px var(--chassis-lo),0 2px 0 var(--groove)}
.recess{background:var(--chassis-lo);border-radius:var(--r-panel);box-shadow:inset 0 2px 5px rgba(0,0,0,.18),0 1px 0 var(--lip)}

/* boundaries / measurement notes */
.notes{display:grid;grid-template-columns:auto 1fr;gap:14px 18px;padding:20px 22px;border-radius:var(--r-key);background:transparent;border:1.5px dashed var(--groove);font-size:14px;line-height:1.65;color:var(--ink-2)}
.notes .silk{padding-top:2px}
.notes ul{margin:0;padding-left:1.1em}
.notes li{margin:.2em 0}

/* ---------- film ---------- */
.film{display:grid;grid-template-columns:minmax(0,1fr) 300px;gap:22px;align-items:start}
.film video{width:100%;aspect-ratio:16/9;background:#000;border-radius:var(--r-glass)}
.chapters{display:grid;gap:8px;margin:0;padding:0;list-style:none}
.chapters button{width:100%;display:grid;grid-template-columns:52px 1fr;gap:10px;align-items:center;text-align:left;border:0;cursor:pointer;padding:11px 12px;border-radius:var(--r-key);background:var(--chassis-hi);box-shadow:0 2px 0 var(--groove);font:600 14px/1.35 var(--sans)}
.chapters button:hover{background:#e3e4de}
.chapters button .t{font:700 12px/1 var(--sans);font-stretch:85%;color:var(--ink-3);font-variant-numeric:tabular-nums}
.chapters button[aria-current="true"]{background:var(--ink);color:var(--chassis-hi);box-shadow:0 2px 0 #000}
.chapters button[aria-current="true"] .t{color:var(--tr)}

/* ---------- gallery + lightbox ---------- */
.shots{display:grid;grid-template-columns:repeat(auto-fill,minmax(250px,1fr));gap:18px}
.shot-btn{display:block;width:100%;padding:0;border:0;background:none;cursor:zoom-in;text-align:left}
.shot-btn .glass{padding:6px;border-radius:12px}
.shot-btn .glass-in{border-radius:7px;aspect-ratio:16/10}
.shot-btn img{width:100%;height:100%;object-fit:cover;object-position:top left;transition:transform .35s}
.shot-btn:hover img{transform:scale(1.03)}
.shot-btn .cap{display:block;margin-top:10px;font:650 14px/1.4 var(--sans);font-stretch:92%}
.lightbox{position:fixed;inset:0;z-index:90;background:rgba(9,11,10,.94);display:none;grid-template-rows:auto 1fr auto;padding:18px;color:var(--glass-ink)}
.lightbox.open{display:grid}
.lightbox figure{margin:0;display:grid;place-items:center;min-height:0}
.lightbox img{max-height:calc(100vh - 140px);width:auto;object-fit:contain;border-radius:6px}
.lightbox .lb-top,.lightbox .lb-bot{display:flex;align-items:center;gap:12px;font:600 14px/1.4 var(--sans)}
.lightbox .lb-top .sp{margin-left:auto}
.lightbox button{background:#2a2d2b;border:0;color:var(--glass-ink);border-radius:var(--r-key);padding:10px 14px;cursor:pointer;font:700 13px/1 var(--sans)}
.lightbox button:hover{background:#3a3e3b}

/* ---------- section scaffolding ---------- */
.sec{padding:clamp(64px,9vw,120px) 0}
.sec-head{display:grid;grid-template-columns:minmax(0,1fr) minmax(0,.8fr);gap:20px 56px;align-items:end;margin-bottom:clamp(32px,4vw,56px)}
.sec-head .silk{grid-column:1/-1;margin-bottom:-6px}
.sec-head .lead{justify-self:start}
.cols-2{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:clamp(24px,4vw,56px);align-items:start}
.stack>*+*{margin-top:18px}

/* footer */
.foot{padding:48px 0 56px;border-top:1px solid var(--groove);box-shadow:inset 0 1px 0 var(--lip)}
.foot .wrap{display:grid;grid-template-columns:1.3fr 1fr 1fr;gap:28px;align-items:start}
.foot h4{margin:0 0 10px;font:700 13px/1.2 var(--sans);font-stretch:80%;color:var(--ink-3)}
.foot ul{list-style:none;margin:0;padding:0}
.foot li{margin:6px 0}
.foot a{text-decoration:none;font-weight:600}
.foot a:hover{text-decoration:underline;text-decoration-color:var(--tr);text-decoration-thickness:2px;text-underline-offset:3px}
.foot .tr-dot{display:inline-block;width:8px;height:8px;border-radius:50%;margin-right:8px;vertical-align:1px}

/* reveal: one orchestrated power-on, nothing else auto-animates */
@keyframes poweron{0%{opacity:0;filter:brightness(2.2) saturate(0)}30%{opacity:1}100%{opacity:1;filter:none}}
.glass-in.on{animation:poweron .9s ease-out both}

/* ---------- responsive ---------- */
@media (max-width:980px){
  .sec-head{grid-template-columns:1fr}
  .film{grid-template-columns:1fr}
  .chapters{grid-template-columns:repeat(auto-fill,minmax(200px,1fr))}
  .foot .wrap{grid-template-columns:1fr 1fr}
}
@media (max-width:760px){
  .bar nav{display:none;position:absolute;top:100%;left:0;right:0;flex-direction:column;background:var(--chassis-hi);padding:10px var(--gut) 16px;border-bottom:1px solid var(--groove)}
  .bar nav.open{display:flex}
  .menu-btn{display:inline-grid;place-items:center;margin-left:auto;width:42px;height:38px;border:0;border-radius:var(--r-key);background:var(--chassis-hi);box-shadow:0 2px 0 var(--groove);cursor:pointer}
  .bar .lang{margin-left:4px}
  .cols-2{grid-template-columns:1fr}
  .foot .wrap{grid-template-columns:1fr}
  .notes{grid-template-columns:1fr}
  .spec{grid-template-columns:1fr}
  .spec dt{border-bottom:0;padding-bottom:0}
}

/* ---------- rotary knob ---------- */
.knob-wrap{display:grid;justify-items:center;gap:10px}
.knob{position:relative;width:118px;height:118px;border-radius:50%;cursor:grab;touch-action:none;outline-offset:8px;border-radius:50%;
  background:radial-gradient(circle at 50% 38%,#eef0ea,#b7b9b1 72%);box-shadow:0 0 0 7px var(--chassis-lo),0 0 0 8px var(--groove),0 9px 18px rgba(0,0,0,.32),inset 0 -3px 6px rgba(0,0,0,.18)}
.knob.turning{cursor:grabbing}
.knob:focus-visible{outline:2px solid var(--ink);border-radius:50%}
.knob-ticks{position:absolute;inset:-22px;pointer-events:none;overflow:visible}
.knob-ticks line{stroke:var(--ink-2);stroke-width:1.6;stroke-linecap:round}
.knob-ticks line.on{stroke:var(--ink);stroke-width:2.6}
.knob-cap{position:absolute;inset:11px;border-radius:50%;background:repeating-conic-gradient(#272a28 0 4deg,#3b3f3c 4deg 8deg);box-shadow:inset 0 1px 2px #ffffff2a,0 4px 8px rgba(0,0,0,.45);transition:transform .12s cubic-bezier(.3,1.4,.5,1)}
.knob.turning .knob-cap{transition:none}
.knob-cap::before{content:"";position:absolute;inset:11px;border-radius:50%;background:radial-gradient(circle at 42% 32%,#555a56,#1c1e1d 70%);box-shadow:inset 0 1px 0 #ffffff24}
.knob-cap::after{content:"";position:absolute;top:6px;left:50%;width:4px;height:24px;margin-left:-2px;border-radius:2px;background:var(--tr);box-shadow:0 0 8px var(--tr)}
.knob-val{font:750 15px/1.2 var(--sans);font-stretch:90%;text-align:center;min-height:2.4em}
.knob-val small{display:block;font-weight:600;font-size:12px;color:var(--ink-3)}

/* channel keys */
.ch-keys{display:grid;gap:10px}
.ch-key{--tr:var(--k);display:grid;grid-template-columns:auto 1fr;gap:4px 12px;align-items:center;text-align:left;width:100%;cursor:pointer;border:0;padding:12px 14px;border-radius:var(--r-key);background:var(--chassis-hi);box-shadow:0 3px 0 var(--groove),0 5px 10px rgba(0,0,0,.1),inset 0 1px 0 #fff9;transition:transform .08s,box-shadow .08s}
.ch-key:hover{background:#e3e4de}
.ch-key:active{transform:translateY(2px);box-shadow:0 1px 0 var(--groove)}
.ch-key .led{grid-row:span 2;width:10px;height:10px;border-radius:50%;background:#8b8e86;box-shadow:inset 0 1px 1px rgba(0,0,0,.4)}
.ch-key[aria-pressed="true"]{background:var(--ink);color:var(--chassis-hi);box-shadow:0 1px 0 #000,inset 0 2px 4px rgba(0,0,0,.6);transform:translateY(2px)}
.ch-key[aria-pressed="true"] .led{background:var(--k);box-shadow:0 0 0 2px #000,0 0 12px var(--k)}
.ch-key b{font:800 15px/1.15 var(--sans);font-stretch:100%}
.ch-key b em{font-style:normal;font-stretch:80%;font-weight:800;font-size:12px;color:var(--k);margin-right:8px;padding:2px 5px;border-radius:3px;background:#0002}
.ch-key[aria-pressed="false"] b em{color:var(--ink);background:var(--k)}
.ch-key span{font:500 12.5px/1.35 var(--sans);color:inherit;opacity:.75}

@media (max-width:420px){.brand-name{font-size:15px;font-stretch:110%}.bar .wrap{gap:12px}}

/* terminal */
.term{padding:22px 24px;min-height:260px}
.term pre{margin:0;white-space:pre-wrap;word-break:break-all;font:500 14px/1.75 ui-monospace,"SFMono-Regular",Menlo,Consolas,monospace;color:#E7EEE9}
.term .c{color:#7d8a82}
.term .p{color:var(--tr4);font-weight:700}
.cur{display:inline-block;width:.6em;height:1.1em;vertical-align:-.18em;background:var(--tr4);margin-left:4px;animation:blink 1.1s steps(1) infinite}
@keyframes blink{50%{opacity:0}}
@media (max-width:560px){.crumb>span{display:none}.crumb-sep{display:none}.prod-name{white-space:nowrap;font-size:15px}}