:root{color-scheme:dark;--bg:#0d1522;--panel:#142135;--panel2:#192940;--field:#111d2f;--line:#2c4057;--text:#f1f5fb;--muted:#a0b0c4;--teal:#73e3ce;--yellow:#ffd18b;--danger:#ff9d99;--good:#7fe2ba}*{box-sizing:border-box}html{scroll-behavior:smooth}body{margin:0;background:var(--bg);font-family:-apple-system,BlinkMacSystemFont,"Malgun Gothic","Apple SD Gothic Neo","Segoe UI",sans-serif;color:var(--text);line-height:1.6;font-size:15px}.ambient{position:fixed;pointer-events:none;z-index:-1;border-radius:50%;filter:blur(92px);opacity:.14}.ambient-one{width:420px;height:420px;top:-220px;left:-140px;background:#3ddbbb}.ambient-two{width:300px;height:500px;right:-190px;top:90px;background:#366bf3}.app-shell{max-width:1020px;margin:0 auto;padding:0 24px 50px}.topbar{padding:29px 0 24px;display:flex;align-items:center;justify-content:space-between;gap:15px;border-bottom:1px solid #24364a}.brand{display:flex;gap:11px;align-items:center;text-decoration:none;color:var(--text)}.brand strong{display:block;font-size:12px;letter-spacing:.14em}.brand small{display:block;font-size:9px;color:#9fb9ca;letter-spacing:.23em}.brand-mark{width:40px;height:40px;display:flex;align-items:center;justify-content:space-around;gap:3px;border-radius:12px;background:linear-gradient(145deg,#265b64,#1d303f);padding:8px}.brand-mark span{background:var(--teal);width:3px;border-radius:3px}.brand-mark span:nth-child(1),.brand-mark span:nth-child(5){height:11px}.brand-mark span:nth-child(2),.brand-mark span:nth-child(4){height:19px}.brand-mark span:nth-child(3){height:25px}.offline-dot{font-size:12px;color:var(--muted);white-space:nowrap}.offline-dot span{display:inline-block;width:6px;height:6px;background:var(--good);border-radius:50%;margin-right:4px;vertical-align:middle}.hero{padding:44px 0 36px}.eyebrow{font-size:11px;letter-spacing:.2em;color:var(--teal);font-weight:700}.eyebrow span{color:#9caec0;font-size:10px;margin-left:6px}.hero h1{font-size:clamp(27px,4.6vw,44px);line-height:1.32;letter-spacing:-.047em;margin:16px 0 14px;word-break:keep-all}.hero h1 em{font-style:normal;color:var(--teal)}.hero p{color:var(--muted);font-size:14px;line-height:1.8;margin:0}.mobile-break{display:none}.tabs{display:grid;grid-template-columns:repeat(3,1fr);gap:8px;background:#0c1420;padding:7px;border:1px solid var(--line);border-radius:15px}.tab{background:transparent;color:#a9bbcd;border:0;padding:14px 6px;font-size:14px;font-weight:700;cursor:pointer;border-radius:11px;font-family:inherit}.tab.active{background:var(--panel2);color:var(--teal);box-shadow:0 2px 10px #0002}.advanced{font-size:9px;font-weight:600;border:1px solid #577184;color:#98b4c2;border-radius:5px;padding:1px 4px;vertical-align:middle;margin-left:2px}.panel-view{padding-top:29px}.section-heading{margin:0 0 19px}.section-heading h2{font-size:22px;letter-spacing:-.04em;margin:0}.section-heading p{color:var(--muted);font-size:13px;margin:3px 0}.choice{display:grid;grid-template-columns:1fr 1fr;gap:9px;margin-bottom:14px}.choice-btn{min-height:50px;border:1px solid var(--line);background:var(--panel);color:#b7c8da;border-radius:12px;cursor:pointer;font:700 14px inherit;font-family:inherit;font-weight:700}.choice-btn.active{border-color:#62bfb8;background:linear-gradient(135deg,#22433f,#1b3441);color:#adf3e5}.sheet{background:linear-gradient(160deg,#142237,#101d30);border:1px solid var(--line);border-radius:18px;padding:25px}.info-line{display:flex;gap:14px;align-items:flex-start;padding:2px 0 22px;border-bottom:1px solid var(--line);margin-bottom:24px}.info-line b{font-size:15px}.info-line p{font-size:12px;color:var(--muted);margin:4px 0 0}.step{background:#1b4b4c;color:var(--teal);min-width:36px;height:36px;border-radius:11px;display:grid;place-items:center;font-size:11px;font-weight:800}.field-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:18px}.field{display:flex;flex-direction:column;font-size:13px;font-weight:700;color:#e3ecf3;min-width:0}.field span{display:inline;font-size:11px;color:var(--teal);font-weight:600}.field>input,.field>select{margin-top:8px;width:100%;padding:14px 13px;min-height:49px;border:1px solid #3d536a;border-radius:10px;background:var(--field);color:var(--text);font-size:17px;font-weight:650;outline:none;font-family:inherit}.field>select{font-size:14px}.field>input:focus,.field>select:focus{border-color:var(--teal);box-shadow:0 0 0 3px #63ded221}.field>input::placeholder{color:#61748a;font-size:13px;font-weight:400}.field>small{color:#94a7ba;font-size:11px;margin-top:7px;line-height:1.55;font-weight:400}.result-card{border:1px solid #408c85;background:linear-gradient(130deg,#123a3d,#153040);border-radius:16px;padding:24px;margin-top:23px;text-align:center}.result-card>small{font-size:12px;color:#b7dcd7;font-weight:600}.result-value{font-size:clamp(26px,4vw,38px);line-height:1.35;font-weight:800;letter-spacing:-.04em;color:#90f4dc;overflow-wrap:anywhere;margin:7px 0}.result-card p{font-size:12px;color:#bbd1da;margin:7px 0 0}.warning{font-size:12px;color:#cad1db;background:#33314070;border:1px solid #685b60;border-radius:11px;padding:12px 14px;line-height:1.75;margin:18px 0 0}.warning strong{color:#ffd7a8}.warning.danger{border-color:#935351;background:#4c2e3570}.warning.danger strong{color:#ffb4b4}.slim{margin-top:16px}.tag{font-size:10px;color:var(--teal);border:1px solid #418d85;border-radius:5px;padding:3px 6px;vertical-align:middle;margin-left:7px}.subheading{display:flex;align-items:baseline;justify-content:space-between;gap:10px;font-weight:800;font-size:15px;margin:0 0 18px}.subheading small{font-size:11px;font-weight:400;color:var(--muted)}.mini{margin-top:22px}.mini .choice-btn{min-height:42px;font-size:12px}.stage-title{margin-top:27px;padding-top:23px;border-top:1px solid var(--line)}.button-outline{border:1px solid #488679;color:var(--teal);background:#19403855;border-radius:9px;font-family:inherit;font-weight:700;font-size:12px;padding:10px 13px;cursor:pointer}.empty-state{text-align:center;padding:30px 12px;border:1px dashed #40546d;border-radius:12px;font-size:12px;line-height:1.9;color:#93a8bc}.stage-card{padding:18px 18px 20px;background:var(--panel2);border:1px solid var(--line);border-radius:12px;margin-bottom:13px}.stage-top{display:flex;align-items:center;justify-content:space-between;gap:10px;margin-bottom:14px}.stage-top strong{font-size:13px}.remove-stage{font:inherit;border:0;background:none;color:#ffb4b4;font-size:12px;cursor:pointer}.stage-fields{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:12px}.stage-fields .field>input{font-size:14px;padding:10px;min-height:41px}.stage-fields .field{font-size:12px}.trace{margin-top:18px}.trace-item{display:flex;align-items:start;justify-content:space-between;gap:10px;border-bottom:1px solid var(--line);padding:13px 4px}.trace-item:last-child{border:0}.trace-item .name{font-size:13px;font-weight:700}.trace-item .figs{text-align:right;font-weight:800;font-size:15px}.trace-item small{display:block;color:#9aafbf;font-size:11px;font-weight:400}.safe{color:var(--good)}.bad{color:var(--danger)}.unknown{color:#e9c58d}.converter-sheet h3{margin:0;font-size:16px}.section-caption{font-size:12px;color:var(--muted);margin:3px 0 18px}.convert-result{margin-top:18px;border:1px solid #315c61;color:#8beddb;background:#1a3a4255;border-radius:11px;text-align:center;padding:14px;font-size:21px;font-weight:800;overflow-wrap:anywhere}.converter-sheet hr{border:0;border-top:1px solid var(--line);margin:30px 0}.footer{margin-top:34px;padding-top:24px;border-top:1px solid var(--line);display:flex;justify-content:space-between;align-items:center;flex-wrap:wrap;gap:9px}.footer strong{font-size:12px;letter-spacing:.1em;display:block}.footer span{display:block;color:#8fa6b9;font-size:11px}.footer a{font-weight:700;font-size:12px;color:var(--teal);text-decoration:none}.footer small{flex-basis:100%;font-size:10px;color:#788ca0;margin-top:9px}.hidden{display:none!important}@media(max-width:650px){.app-shell{padding:0 16px 45px}.topbar{padding:18px 0}.brand strong{font-size:10px}.brand small{font-size:8px}.brand-mark{width:35px;height:35px}.offline-dot{font-size:10px}.hero{padding:30px 0 25px}.hero p{font-size:12px}.mobile-break{display:block}.tabs{gap:3px;padding:5px}.tab{font-size:12px;padding:13px 3px}.advanced{display:none}.panel-view{padding-top:24px}.section-heading h2{font-size:20px}.sheet{padding:17px 16px}.choice-btn{font-size:12px;line-height:1.35}.field-grid{grid-template-columns:1fr;gap:16px}.result-card{padding:20px 14px}.stage-fields{grid-template-columns:1fr 1fr}.stage-title{align-items:center}.subheading small{font-size:10px}.footer{align-items:flex-start}}
/* v0.2: chain-first UI */
.tabs{grid-template-columns:repeat(2,1fr)}
.notice{border:1px solid #375368;border-radius:14px;background:#15283a;padding:16px 20px;margin:0 0 25px;font-size:13px;color:#dbeaf2}
.notice strong{color:#95f0de}.notice p{margin:5px 0 0;line-height:1.8}.notice p.dim{color:#9db0c1;font-size:11px}
.chain-builder{display:flex;flex-direction:column;align-items:stretch}
.equipment-card{background:linear-gradient(160deg,#16283d,#101d30);border:1px solid var(--line);border-radius:17px;padding:23px}
.equipment-head{display:flex;align-items:center;gap:13px;margin-bottom:19px}.unit-icon{background:#214a4c;color:#a0f3e5;border-radius:10px;width:36px;height:36px;display:grid;place-items:center;flex-shrink:0;font-weight:800;font-size:12px}
.equipment-head h3{font-size:17px;line-height:1.4;margin:0}.equipment-head p{font-size:12px;margin:1px 0;color:var(--muted)}.equipment-kind{margin-left:auto;background:#23374c;padding:4px 9px;color:#9dbbc8;font-size:10px;font-weight:700;border-radius:99px;white-space:nowrap}
.field>input + select{margin-top:7px}.field>small{max-width:420px}
.flow-arrow,.insert-connector{display:flex;flex-direction:column;align-items:center;gap:0}.flow-arrow{height:55px;justify-content:center}.flow-arrow span{height:11px;width:2px;background:#437c79}.flow-arrow b,.flowline{font-size:22px;line-height:1.2;color:var(--teal)}
.insert-connector{padding:10px 0 12px;gap:5px}.add-between{cursor:pointer;background:#163735;border:1px dashed #65bfb1;color:#abf4e2;padding:10px 18px;border-radius:999px;font:700 12px inherit;font-family:inherit;font-weight:700;min-height:42px}.add-between:hover,.add-between:focus-visible{border-style:solid;background:#22534a;outline:none}.flowline{font-size:17px}
.stage-status{margin-top:17px;padding-top:12px;border-top:1px solid #2c4057;font-size:12px;color:#a7c3cb}.stage-status.good{color:#8be7c4}.stage-status.bad{color:#ffaeae}.stage-status.unknown{color:#e7c58c}
.outboard-card{border-color:#48667b;background:linear-gradient(160deg,#1c2e44,#172337)}
.outboard-card .equipment-head{margin-bottom:15px}.outboard-card .unit-icon{background:#34465d;color:#d7e9f2}
.outboard-card .stage-fields{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:14px}
.remove-stage{border:1px solid #81585c;background:#3d252844;color:#ffb8b8;font-size:11px;border-radius:8px;padding:6px 9px;white-space:nowrap}
.summary-text{font-size:12px;color:#bed4dc;margin:20px 0 0;text-align:center}.trace{margin-top:20px}.trace-item .figs{font-size:13px}.trace-item .name{font-size:13px}
@media(max-width:650px){.equipment-card{padding:17px 15px}.equipment-head h3{font-size:15px}.equipment-head p{font-size:11px}.equipment-kind{font-size:9px;padding:4px 6px}.outboard-card .stage-fields{grid-template-columns:1fr}.notice{padding:15px}}

/* v0.3: clear, non-technical wording and two-scenario compressor readouts */
.inline-tip{margin:12px 0 0;padding:9px 12px;color:#b6d5d7;background:#1b3b4233;border:1px solid #3c686b;border-radius:9px;font-size:12px;line-height:1.65}
.outboard-card .stage-fields .field>select{font-size:13px;padding:10px;min-height:41px}
.trace-item .alternative{color:#a4e5d4;margin-top:3px}
.trace-item>div:first-child{min-width:0;flex:1}
.trace-item .figs{max-width:48%}
@media(max-width:650px){.trace-item{flex-direction:column;gap:6px}.trace-item .figs{text-align:left;max-width:100%}}

/* v0.4 — supplied identity and contextual stage tips */
.brand-logo{display:block;width:92px;height:auto;max-height:58px;object-fit:contain;flex-shrink:0}
.brand-wording{display:flex;flex-direction:column;justify-content:center}
.brand-wording strong{letter-spacing:.025em;font-size:13px;white-space:nowrap}
.brand-wording small{font-size:9px;letter-spacing:.10em}
.topbar{min-height:88px}
.outboard-card .stage-fields>.equipment-tip{grid-column:1/-1;margin:0 0 3px;border-color:#395c6b;background:rgba(32,70,79,.34);color:#c6e7e5;font-size:12px}
.equipment-tip strong{color:#91e9d7}
.equipment-tip.is-compressor{border-color:#467c70;background:rgba(21,76,73,.36)}
.calculation-caution{margin-top:18px;border:1px solid #526273;border-radius:12px;padding:15px 17px;background:rgba(31,43,61,.60);color:#dce6eb;font-size:12px;line-height:1.85}
.calculation-caution>strong{display:block;color:#aeeadf;font-size:13px;margin-bottom:5px}
.calculation-caution p{margin:0;color:#c5d3dc}.calculation-caution b{color:#f0f7fb}
.method-details{margin-top:12px;padding-top:9px;border-top:1px solid #385065}
.method-details summary{color:#99c6ca;cursor:pointer;user-select:none;list-style:disclosure-closed;font-weight:600}
.method-details[open] summary{margin-bottom:7px}.method-details p{font-size:11px;color:#a7bccb}
@media(max-width:650px){.topbar{min-height:75px}.brand-logo{width:69px;max-height:47px}.brand{gap:7px}.brand-wording strong{font-size:11px;letter-spacing:0}.brand-wording small{font-size:8px;letter-spacing:.045em}.offline-dot{font-size:9px}.calculation-caution{padding:13px}}

/* v0.5 — wording cleanup and centered footer */
.footer{justify-content:center;align-items:center;flex-direction:column;text-align:center;gap:8px}.footer strong{display:block}.footer a{display:block}.footer small{margin-top:4px}

/* v0.6: non-technical wording and unobtrusive signal reference */
.result-basis{font-size:11px!important;color:#9dbfbf!important;letter-spacing:.005em;margin-top:10px!important}