:root{color-scheme:light;--bg:#f4f8f6;--surface:#fff;--surface-soft:#eef6f2;--surface-raised:#fff;--text:#13231e;--text-soft:#5f706a;--text-faint:#81908b;--border:#dce7e2;--border-strong:#c9d9d2;--primary:#0f766e;--primary-dark:#0b5d57;--primary-soft:#dff3ee;--primary-faint:#f2fbf8;--accent:#d97706;--accent-soft:#fff4dc;--danger:#b42318;--danger-soft:#fef1ef;--success:#16803c;--shadow-sm:0 8px 24px rgba(17,53,43,.06);--shadow-md:0 20px 60px rgba(17,53,43,.1);--radius-sm:10px;--radius-md:18px;--radius-lg:28px;--container:1180px;--header-height:72px}html[data-theme=dark]{color-scheme:dark;--bg:#0b1512;--surface:#111e1a;--surface-soft:#142720;--surface-raised:#15231f;--text:#edf8f4;--text-soft:#a7bab3;--text-faint:#82978f;--border:#253c34;--border-strong:#345248;--primary:#58c7b5;--primary-dark:#83decf;--primary-soft:#173c35;--primary-faint:#102a25;--accent:#f4b85f;--accent-soft:#3e2d16;--danger:#ff8a80;--danger-soft:#3a1d1b;--success:#77d69a;--shadow-sm:0 8px 26px rgba(0,0,0,.18);--shadow-md:0 24px 70px rgba(0,0,0,.26)}*{box-sizing:border-box}html{scroll-behavior:smooth;scroll-padding-top:calc(var(--header-height) + 20px)}body{margin:0;min-width:320px;font-family:"Noto Sans SC","PingFang SC","Microsoft YaHei","Source Han Sans SC",system-ui,-apple-system,BlinkMacSystemFont,"Segoe UI",sans-serif;color:var(--text);background:radial-gradient(circle at 8% 2%,rgba(15,118,110,.08),transparent 28rem),var(--bg);line-height:1.7;-webkit-font-smoothing:antialiased;text-rendering:optimizeLegibility}body,button,input,select{font:inherit}button,a,input,select{-webkit-tap-highlight-color:transparent}button{color:inherit}a{color:inherit;text-decoration:none}img,svg,canvas{display:block;max-width:100%}[hidden]{display:none!important}::selection{color:#fff;background:var(--primary)}.container{width:min(calc(100% - 40px),var(--container));margin-inline:auto}.skip-link{position:fixed;top:12px;left:12px;z-index:999;padding:10px 16px;color:#fff;background:var(--primary-dark);border-radius:8px;transform:translateY(-150%);transition:transform 180ms ease}.skip-link:focus{transform:translateY(0)}
.site-header{position:sticky;top:0;z-index:50;min-height:var(--header-height);background:color-mix(in srgb,var(--surface) 90%,transparent);border-bottom:1px solid color-mix(in srgb,var(--border) 80%,transparent);backdrop-filter:blur(18px)}.header-inner{display:flex;align-items:center;justify-content:space-between;min-height:var(--header-height);gap:28px}.brand{display:inline-flex;align-items:center;gap:12px;flex:0 0 auto}.brand-mark{display:grid;width:44px;height:44px;place-items:center;color:#fff;font-size:1rem;font-weight:800;letter-spacing:-.04em;background:linear-gradient(145deg,#0f766e,#14a18d);border-radius:13px;box-shadow:0 8px 20px rgba(15,118,110,.24)}.brand-copy{display:flex;flex-direction:column;line-height:1.25}.brand-copy strong{font-size:.98rem;letter-spacing:.02em}.brand-copy small{margin-top:3px;color:var(--text-faint);font-size:.68rem;letter-spacing:.08em}.top-nav{display:flex;align-items:center;gap:30px;margin-left:auto}.top-nav a{position:relative;padding:23px 0;color:var(--text-soft);font-size:.92rem;font-weight:600;transition:color 160ms ease}.top-nav a::after{position:absolute;right:0;bottom:15px;left:0;height:2px;content:"";background:var(--primary);border-radius:999px;transform:scaleX(0);transition:transform 180ms ease}.top-nav a:hover,.top-nav a:focus-visible{color:var(--primary)}.top-nav a:hover::after,.top-nav a:focus-visible::after{transform:scaleX(1)}.header-actions{display:flex;align-items:center;gap:12px}.privacy-pill{display:inline-flex;align-items:center;gap:7px;padding:7px 11px;color:var(--primary-dark);font-size:.76rem;font-weight:700;background:var(--primary-soft);border:1px solid color-mix(in srgb,var(--primary) 18%,var(--border));border-radius:999px}.status-dot{width:7px;height:7px;background:var(--success);border-radius:50%;box-shadow:0 0 0 4px color-mix(in srgb,var(--success) 12%,transparent)}.icon-button{display:inline-grid;width:40px;height:40px;padding:0;place-items:center;color:var(--text-soft);background:var(--surface);border:1px solid var(--border);border-radius:11px;cursor:pointer;transition:color 160ms ease,border-color 160ms ease,transform 160ms ease,background 160ms ease}.icon-button:hover{color:var(--primary);border-color:color-mix(in srgb,var(--primary) 45%,var(--border));transform:translateY(-1px)}.icon-button svg{width:19px;height:19px;fill:none;stroke:currentColor;stroke-width:1.8;stroke-linecap:round;stroke-linejoin:round}.moon-icon,html[data-theme=dark] .sun-icon{display:none}html[data-theme=dark] .moon-icon{display:block}
.hero{position:relative;overflow:hidden;padding:54px 0 70px;background:linear-gradient(180deg,color-mix(in srgb,var(--surface) 72%,transparent),transparent 80%),linear-gradient(115deg,var(--primary-faint),transparent 60%);border-bottom:1px solid var(--border)}.hero-orb{position:absolute;pointer-events:none;border-radius:50%;filter:blur(1px)}.hero-orb--one{top:-180px;right:-150px;width:480px;height:480px;background:radial-gradient(circle,rgba(20,184,166,.18),transparent 68%)}.hero-orb--two{bottom:-220px;left:18%;width:430px;height:430px;background:radial-gradient(circle,rgba(217,119,6,.1),transparent 70%)}.breadcrumb{position:relative;display:flex;align-items:center;flex-wrap:wrap;gap:9px;margin-bottom:38px;color:var(--text-faint);font-size:.81rem}.breadcrumb a{transition:color 150ms ease}.breadcrumb a:hover{color:var(--primary)}.hero-grid{position:relative;display:grid;grid-template-columns:minmax(0,1.15fr) minmax(380px,.85fr);align-items:center;gap:74px}.eyebrow,.section-kicker,.mini-label{display:inline-flex;align-items:center;gap:8px;color:var(--primary);font-size:.76rem;font-weight:800;letter-spacing:.12em;text-transform:uppercase}.eyebrow::before,.section-kicker::before{width:24px;height:2px;content:"";background:currentColor;border-radius:999px}.hero h1{max-width:720px;margin:14px 0 18px;font-size:clamp(2.6rem,6vw,5rem);line-height:1.04;letter-spacing:-.055em}.hero-copy>p{max-width:680px;margin:0;color:var(--text-soft);font-size:clamp(1rem,1.8vw,1.16rem);line-height:1.9}.hero-actions{display:flex;flex-wrap:wrap;gap:12px;margin-top:30px}.button{display:inline-flex;min-height:48px;align-items:center;justify-content:center;gap:9px;padding:0 20px;font-weight:750;line-height:1;border:1px solid transparent;border-radius:12px;cursor:pointer;transition:transform 160ms ease,box-shadow 160ms ease,color 160ms ease,background 160ms ease,border-color 160ms ease}.button:hover{transform:translateY(-2px)}.button svg{width:18px;height:18px;fill:none;stroke:currentColor;stroke-width:2;stroke-linecap:round;stroke-linejoin:round}.button--primary{color:#fff;background:linear-gradient(135deg,var(--primary),color-mix(in srgb,var(--primary) 72%,#0ea5a5));box-shadow:0 12px 28px rgba(15,118,110,.22)}.button--primary:hover{box-shadow:0 16px 34px rgba(15,118,110,.28)}.button--ghost{color:var(--text);background:color-mix(in srgb,var(--surface) 75%,transparent);border-color:var(--border)}.button--ghost:hover{color:var(--primary);border-color:color-mix(in srgb,var(--primary) 40%,var(--border))}.button--secondary{color:var(--text-soft);background:var(--surface-soft);border-color:var(--border)}.hero-points{display:flex;flex-wrap:wrap;gap:22px;padding:0;margin:38px 0 0;color:var(--text-soft);font-size:.84rem;list-style:none}.hero-points li{display:inline-flex;align-items:center;gap:9px}.hero-points span{color:var(--primary);font-family:ui-monospace,SFMono-Regular,Menlo,Consolas,monospace;font-size:.72rem;font-weight:800}
.formula-stage{position:relative;padding:26px;overflow:hidden;background:color-mix(in srgb,var(--surface) 88%,transparent);border:1px solid color-mix(in srgb,var(--border-strong) 85%,transparent);border-radius:var(--radius-lg);box-shadow:var(--shadow-md);backdrop-filter:blur(12px)}.formula-stage::after{position:absolute;right:-60px;bottom:-90px;width:230px;height:230px;content:"";background:radial-gradient(circle,rgba(15,118,110,.16),transparent 70%);border-radius:50%}.formula-stage__top,.formula-card__head,.result-panel__head,.card-heading-row{display:flex;align-items:center;justify-content:space-between;gap:12px}.formula-stage__top{color:var(--text-soft);font-size:.78rem;font-weight:700;letter-spacing:.08em}.formula-tag{padding:5px 9px;color:var(--accent);background:var(--accent-soft);border-radius:999px;letter-spacing:.03em}.hero-equation{display:flex;align-items:center;justify-content:center;gap:20px;min-height:210px;color:var(--text);font-family:Georgia,"Times New Roman",serif;font-size:clamp(2.5rem,5vw,4rem)}.hero-equation b{color:var(--text-soft);font-weight:400}.fraction{display:inline-grid;align-items:center;line-height:1.08;text-align:center}.fraction i{padding:0 8px;font-style:normal}.fraction i:first-child{padding-bottom:10px;border-bottom:3px solid currentColor}.fraction i:last-child{padding-top:5px}.fraction sub,.live-formula sub,.equation-card sub,.inline-equation sub{font-size:.52em;vertical-align:-.3em}.formula-note{display:flex;align-items:center;gap:12px;padding:14px 16px;color:var(--text-soft);background:var(--surface-soft);border:1px solid var(--border);border-radius:14px}.formula-note>span{display:grid;width:30px;height:30px;flex:0 0 auto;place-items:center;color:var(--primary);font-weight:900;background:var(--primary-soft);border-radius:9px}.formula-note p{margin:0;font-size:.82rem}.formula-chip-row{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:10px;margin-top:14px}.formula-chip-row span{padding:12px;overflow:hidden;color:var(--primary-dark);font-family:Georgia,"Times New Roman",serif;font-size:.92rem;text-align:center;text-overflow:ellipsis;white-space:nowrap;background:var(--primary-faint);border:1px solid color-mix(in srgb,var(--primary) 20%,var(--border));border-radius:12px}
.calculator-section,.guide-section,.related-section{padding:88px 0}.calculator-section{background:var(--surface);border-bottom:1px solid var(--border)}.section-heading{display:flex;align-items:end;justify-content:space-between;gap:40px;margin-bottom:34px}.section-heading h2{margin:8px 0 0;font-size:clamp(1.65rem,3vw,2.4rem);line-height:1.25;letter-spacing:-.035em}.section-heading>p{max-width:490px;margin:0;color:var(--text-soft);font-size:.92rem;text-align:right}.section-heading--center{display:block;max-width:730px;margin-right:auto;margin-left:auto;text-align:center}.section-heading--center .section-kicker::before{display:none}.section-heading--center>p{margin:10px auto 0;text-align:center}.calculator-layout{display:grid;grid-template-columns:minmax(0,1.72fr) minmax(280px,.72fr);align-items:start;gap:24px}.card{background:var(--surface-raised);border:1px solid var(--border);border-radius:var(--radius-md);box-shadow:var(--shadow-sm)}.calculator-card{position:relative;padding:30px;overflow:hidden}.card-accent{position:absolute;top:0;right:0;left:0;height:4px;background:linear-gradient(90deg,var(--primary),#2bb7a1 55%,var(--accent))}.calculator-card__head{display:flex;align-items:center;justify-content:space-between;gap:20px;padding-bottom:24px;margin-bottom:24px;border-bottom:1px solid var(--border)}.calculator-card__head h3,.formula-card h3,.checklist-card h3,.note-card h3{margin:4px 0 0;font-size:1.12rem;letter-spacing:-.015em}.text-button{display:inline-flex;align-items:center;gap:7px;padding:8px 11px;color:var(--primary);font-size:.82rem;font-weight:700;background:var(--primary-faint);border:1px solid color-mix(in srgb,var(--primary) 22%,var(--border));border-radius:10px;cursor:pointer}.text-button svg{width:15px;height:15px;fill:none;stroke:currentColor;stroke-width:2;stroke-linecap:round}.field{margin-bottom:22px}.field-label{display:flex;align-items:center;justify-content:space-between;gap:12px;margin-bottom:8px;color:var(--text);font-size:.88rem;font-weight:750}.field-help{min-height:1.4em;margin:7px 0 0;color:var(--text-faint);font-size:.76rem;line-height:1.55}.input-unit-grid{display:grid;grid-template-columns:minmax(0,1.7fr) minmax(145px,.7fr);gap:10px}.number-wrap,.select-wrap{position:relative}.number-wrap--with-unit .control{padding-right:112px}.fixed-unit{position:absolute;top:50%;right:14px;color:var(--text-faint);font-size:.78rem;font-weight:700;pointer-events:none;transform:translateY(-50%)}.control{width:100%;height:50px;padding:0 14px;color:var(--text);font-size:.94rem;font-weight:650;background:var(--surface);border:1px solid var(--border-strong);border-radius:12px;outline:none;transition:border-color 160ms ease,box-shadow 160ms ease,background 160ms ease}.control::placeholder{color:var(--text-faint);font-weight:450}.control:hover{border-color:color-mix(in srgb,var(--primary) 35%,var(--border-strong))}.control:focus{border-color:var(--primary);box-shadow:0 0 0 4px color-mix(in srgb,var(--primary) 14%,transparent)}.control--select{padding-right:42px;appearance:none;cursor:pointer}html[data-theme=dark] .control{background:#0e1a16}.select-arrow{position:absolute;top:50%;right:14px;width:16px;height:16px;color:var(--text-faint);fill:none;stroke:currentColor;stroke-width:2;stroke-linecap:round;stroke-linejoin:round;pointer-events:none;transform:translateY(-50%)}.conditional-field{animation:revealField 180ms ease both}@keyframes revealField{from{opacity:0;transform:translateY(-5px)}to{opacity:1;transform:translateY(0)}}.form-actions{display:grid;grid-template-columns:minmax(0,1fr) auto;gap:10px;margin-top:8px}.button--calculate{min-height:52px}

.result-panel{margin-top:28px;padding:24px;background:radial-gradient(circle at 95% 0%,rgba(15,118,110,.11),transparent 15rem),var(--primary-faint);border:1px solid color-mix(in srgb,var(--primary) 28%,var(--border));border-radius:16px;animation:resultIn 240ms ease both}@keyframes resultIn{from{opacity:0;transform:translateY(8px)}to{opacity:1;transform:translateY(0)}}.result-panel.is-error{background:var(--danger-soft);border-color:color-mix(in srgb,var(--danger) 30%,var(--border))}.result-panel__head{align-items:start}.result-panel__head h3{margin:4px 0 0;font-size:1.2rem}.icon-button--small{width:35px;height:35px;background:color-mix(in srgb,var(--surface) 72%,transparent)}.icon-button--small svg{width:16px;height:16px}.result-main{display:flex;align-items:baseline;flex-wrap:wrap;gap:10px;margin:22px 0 18px;font-family:ui-monospace,SFMono-Regular,Menlo,Consolas,monospace}.result-symbol{color:var(--primary);font-size:1rem;font-weight:800}.result-main strong{font-size:clamp(2rem,5vw,3.4rem);line-height:1.05;letter-spacing:-.055em}.result-main>span:last-child{color:var(--text-soft);font-size:.88rem;font-weight:700}.result-detail{padding-top:17px;color:var(--text-soft);font-size:.84rem;border-top:1px solid color-mix(in srgb,var(--primary) 18%,var(--border))}.result-detail p{margin:0 0 8px}.result-detail p:last-child{margin-bottom:0}.result-detail strong{color:var(--text)}.result-detail .result-callout{padding:10px 12px;margin-top:12px;color:var(--primary-dark);font-weight:700;background:color-mix(in srgb,var(--primary-soft) 72%,transparent);border-radius:10px}.result-panel.is-error .result-detail .result-callout{color:var(--danger);background:color-mix(in srgb,var(--danger-soft) 75%,transparent)}.chart-block{padding-top:20px;margin-top:20px;border-top:1px solid color-mix(in srgb,var(--primary) 18%,var(--border))}.chart-head{display:flex;align-items:start;justify-content:space-between;gap:16px;margin-bottom:10px}.chart-head h4{margin:0;font-size:.92rem}.chart-head span{color:var(--text-faint);font-size:.72rem}.chart-wrap{position:relative;width:100%;min-height:230px;overflow:hidden;background:color-mix(in srgb,var(--surface) 88%,transparent);border:1px solid var(--border);border-radius:12px}#result-chart{width:100%;height:260px}.chart-summary{margin:8px 0 0;color:var(--text-faint);font-size:.72rem}.calculator-sidebar{display:grid;gap:18px}.formula-card,.checklist-card,.toc-card,.note-card{padding:22px}.live-dot{display:inline-flex;align-items:center;gap:6px;color:var(--text-faint);font-size:.68rem}.live-dot i{width:6px;height:6px;background:var(--success);border-radius:50%;box-shadow:0 0 0 3px color-mix(in srgb,var(--success) 12%,transparent)}.live-formula{padding:26px 10px;margin:17px 0 13px;color:var(--primary-dark);font-family:Georgia,"Times New Roman",serif;font-size:clamp(1.55rem,3vw,2rem);text-align:center;background:var(--primary-faint);border:1px dashed color-mix(in srgb,var(--primary) 30%,var(--border));border-radius:13px}.formula-card>p{margin:0 0 18px;color:var(--text-soft);font-size:.8rem}.formula-variables{display:grid;gap:10px}.formula-variables>div{display:grid;grid-template-columns:58px minmax(0,1fr);align-items:center;gap:10px;padding-top:10px;color:var(--text-soft);font-size:.76rem;border-top:1px solid var(--border)}.formula-variables code{color:var(--primary);font-family:Georgia,"Times New Roman",serif;font-size:.9rem;font-weight:700}.checklist-card ul{display:grid;gap:11px;padding:0;margin:16px 0 0;list-style:none}.checklist-card li{display:flex;align-items:center;gap:9px;color:var(--text-soft);font-size:.8rem}.checklist-card li span{display:grid;width:20px;height:20px;flex:0 0 auto;place-items:center;color:var(--primary);font-size:.7rem;font-weight:900;background:var(--primary-soft);border-radius:50%}
.guide-section{background:var(--bg);border-bottom:1px solid var(--border)}.guide-grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:20px}.guide-card{position:relative;padding:28px;overflow:hidden;background:var(--surface);border:1px solid var(--border);border-radius:var(--radius-md);transition:transform 180ms ease,border-color 180ms ease,box-shadow 180ms ease}.guide-card:hover{border-color:color-mix(in srgb,var(--primary) 34%,var(--border));box-shadow:var(--shadow-sm);transform:translateY(-4px)}.guide-number{position:absolute;top:18px;right:22px;color:color-mix(in srgb,var(--primary) 20%,var(--border));font-family:Georgia,"Times New Roman",serif;font-size:2.5rem;font-weight:700}.guide-icon{display:inline-grid;min-width:56px;height:42px;padding:0 11px;place-items:center;color:var(--primary);font-family:ui-monospace,SFMono-Regular,Menlo,Consolas,monospace;font-size:.82rem;font-weight:800;background:var(--primary-soft);border-radius:11px}.guide-card h3{margin:22px 0 9px;font-size:1.08rem}.guide-card p{margin:0;color:var(--text-soft);font-size:.85rem}
.knowledge-section{padding:96px 0;background:linear-gradient(180deg,color-mix(in srgb,var(--surface) 70%,transparent),transparent 22rem),var(--bg)}.knowledge-layout{display:grid;grid-template-columns:minmax(0,1fr) 280px;align-items:start;gap:56px}.article-content{min-width:0}.article-content>h2{margin:56px 0 14px;font-size:clamp(1.45rem,2.6vw,2rem);line-height:1.35;letter-spacing:-.03em;scroll-margin-top:90px}.article-content>h2:first-of-type{margin-top:14px}.article-content>p{margin:0 0 18px;color:var(--text-soft);font-size:.95rem}.article-content strong{color:var(--text)}.article-content blockquote{position:relative;padding:24px 26px 20px 130px;margin:28px 0;overflow:hidden;color:var(--text-soft);background:var(--surface);border:1px solid var(--border);border-left:4px solid var(--primary);border-radius:0 16px 16px 0}.article-content blockquote>span{position:absolute;top:25px;left:24px;width:82px;color:var(--text-faint);font-size:.7rem;font-weight:800}.article-content blockquote strong{display:block;color:var(--primary-dark);font-family:Georgia,"Times New Roman",serif;font-size:1.5rem}.article-content blockquote p{margin:8px 0 0;font-size:.82rem}.inline-equation{padding:19px 22px;margin:20px 0;color:var(--primary-dark);font-family:Georgia,"Times New Roman",serif;font-size:clamp(1.18rem,2.6vw,1.6rem);text-align:center;background:var(--primary-faint);border:1px solid color-mix(in srgb,var(--primary) 24%,var(--border));border-radius:13px}.equation-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:16px;margin:24px 0}.equation-card{padding:22px;background:var(--surface);border:1px solid var(--border);border-radius:15px}.equation-card--highlight{background:var(--primary-faint);border-color:color-mix(in srgb,var(--primary) 28%,var(--border))}.equation-card>span{color:var(--text-faint);font-size:.72rem;font-weight:800;letter-spacing:.08em}.equation-card strong{display:block;margin:14px 0 10px;color:var(--primary-dark);font-family:Georgia,"Times New Roman",serif;font-size:1.45rem}.equation-card p{margin:0;color:var(--text-soft);font-size:.8rem}.table-wrap{margin:24px 0;overflow-x:auto;background:var(--surface);border:1px solid var(--border);border-radius:14px}table{width:100%;min-width:620px;border-collapse:collapse;font-size:.84rem}th,td{padding:14px 16px;text-align:left;border-bottom:1px solid var(--border)}th{color:var(--text-faint);font-size:.72rem;letter-spacing:.04em;background:var(--surface-soft)}tbody tr:last-child td{border-bottom:0}td.positive{color:var(--success);font-weight:700}td.negative{color:var(--danger);font-weight:700}.example-box{padding:24px;margin:24px 0;background:linear-gradient(135deg,var(--primary-faint),var(--surface));border:1px solid color-mix(in srgb,var(--primary) 25%,var(--border));border-radius:16px}.example-box__head{display:flex;align-items:center;justify-content:space-between;gap:16px;padding-bottom:15px;border-bottom:1px solid color-mix(in srgb,var(--primary) 18%,var(--border))}.example-box__head span{color:var(--text-soft);font-size:.82rem}.example-box__head strong{color:var(--primary-dark);font-family:ui-monospace,SFMono-Regular,Menlo,Consolas,monospace}.example-box p{margin:15px 0 0;color:var(--text-soft);font-size:.84rem}.example-box .inline-equation{margin:15px 0 0}.content-list{display:grid;gap:12px;padding:0;margin:22px 0;list-style:none}.content-list li{position:relative;padding:13px 16px 13px 42px;color:var(--text-soft);font-size:.87rem;background:var(--surface);border:1px solid var(--border);border-radius:12px}.content-list li::before{position:absolute;top:16px;left:16px;width:9px;height:9px;content:"";background:var(--primary);border-radius:50%;box-shadow:0 0 0 4px var(--primary-soft)}.knowledge-aside{position:sticky;top:94px;display:grid;gap:16px}.toc-card nav{display:grid;margin-top:14px;border-top:1px solid var(--border)}.toc-card nav a{padding:11px 0;color:var(--text-soft);font-size:.8rem;border-bottom:1px solid var(--border);transition:color 150ms ease,padding-left 150ms ease}.toc-card nav a:hover{padding-left:5px;color:var(--primary)}.toc-card nav a:last-child{border-bottom:0}.note-card{position:relative;padding-left:62px;background:var(--accent-soft);border-color:color-mix(in srgb,var(--accent) 20%,var(--border))}.note-icon{position:absolute;top:23px;left:22px;display:grid;width:28px;height:28px;place-items:center;color:var(--accent);font-family:Georgia,"Times New Roman",serif;font-weight:900;background:var(--surface);border-radius:50%}.note-card h3{margin-top:0}.note-card p{margin:8px 0 0;color:var(--text-soft);font-size:.78rem}
.related-section{background:var(--surface);border-top:1px solid var(--border)}.related-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:16px}.related-card{display:grid;grid-template-columns:50px minmax(0,1fr) auto;align-items:center;gap:16px;padding:20px;background:var(--surface-raised);border:1px solid var(--border);border-radius:15px;transition:transform 170ms ease,border-color 170ms ease,box-shadow 170ms ease}.related-card:hover{border-color:color-mix(in srgb,var(--primary) 34%,var(--border));box-shadow:var(--shadow-sm);transform:translateY(-3px)}.related-card>span:last-child{color:var(--primary);font-size:1.2rem}.related-icon{display:grid;width:50px;height:50px;place-items:center;color:var(--primary);font-family:Georgia,"Times New Roman",serif;font-weight:800;background:var(--primary-soft);border-radius:13px}.related-card h3{margin:0 0 4px;font-size:.95rem}.related-card p{margin:0;color:var(--text-soft);font-size:.78rem}

.site-footer{padding:56px 0 24px;color:#c8ddd6;background:#0e2620}.footer-grid{display:grid;grid-template-columns:minmax(0,1.55fr) repeat(2,minmax(150px,.55fr));gap:60px;padding-bottom:42px}.brand--footer .brand-copy strong{color:#fff}.brand--footer .brand-copy small{color:#8fb5aa}.footer-grid>div:first-child p{max-width:520px;margin:18px 0 0;color:#91ada5;font-size:.82rem}.footer-grid h3{margin:0 0 16px;color:#fff;font-size:.84rem}.footer-grid>div:not(:first-child){display:flex;flex-direction:column;align-items:flex-start}.footer-grid>div:not(:first-child) a{margin-bottom:10px;color:#91ada5;font-size:.78rem;transition:color 150ms ease}.footer-grid>div:not(:first-child) a:hover{color:#fff}.footer-bottom{display:flex;align-items:center;justify-content:space-between;gap:20px;padding-top:22px;color:#78968d;font-size:.72rem;border-top:1px solid #24443a}.toast{position:fixed;right:24px;bottom:24px;z-index:100;max-width:min(360px,calc(100% - 48px));padding:12px 16px;color:#fff;font-size:.82rem;font-weight:700;background:#163a31;border:1px solid #2e5a4e;border-radius:11px;box-shadow:0 16px 40px rgba(0,0,0,.2);opacity:0;pointer-events:none;transform:translateY(12px);transition:opacity 180ms ease,transform 180ms ease}.toast.is-visible{opacity:1;transform:translateY(0)}:focus-visible{outline:3px solid color-mix(in srgb,var(--primary) 38%,transparent);outline-offset:2px}
@media(max-width:1020px){.top-nav{display:none}.hero-grid{grid-template-columns:1fr;gap:42px}.formula-stage{max-width:650px}.calculator-layout,.knowledge-layout{grid-template-columns:1fr}.calculator-sidebar{grid-template-columns:repeat(2,minmax(0,1fr))}.knowledge-aside{position:static;grid-template-columns:minmax(0,1fr) minmax(0,1fr)}.guide-grid{grid-template-columns:repeat(2,minmax(0,1fr))}.guide-card:last-child{grid-column:1/-1}}
@media(max-width:720px){:root{--header-height:64px}.container{width:min(calc(100% - 28px),var(--container))}.brand-mark{width:39px;height:39px;border-radius:11px;font-size:.9rem}.brand-copy small,.privacy-pill{display:none}.header-inner{gap:12px}.hero{padding:35px 0 50px}.breadcrumb{margin-bottom:26px}.hero h1{margin-top:12px;font-size:clamp(2.4rem,13vw,3.6rem)}.hero-copy>p{font-size:.95rem}.hero-points{display:grid;gap:10px;margin-top:28px}.formula-stage{padding:20px;border-radius:21px}.hero-equation{min-height:170px}.calculator-section,.guide-section,.related-section,.knowledge-section{padding:64px 0}.section-heading{display:block}.section-heading>p{margin-top:10px;text-align:left}.calculator-card{padding:20px}.calculator-card__head{align-items:flex-start;flex-direction:column}.input-unit-grid{grid-template-columns:1fr}.calculator-sidebar,.knowledge-aside,.guide-grid,.equation-grid,.related-grid{grid-template-columns:1fr}.guide-card:last-child{grid-column:auto}.article-content blockquote{padding:76px 20px 20px}.article-content blockquote>span{top:20px;left:20px}.example-box__head{align-items:flex-start;flex-direction:column;gap:5px}.footer-grid{grid-template-columns:1fr 1fr;gap:36px}.footer-grid>div:first-child{grid-column:1/-1}.footer-bottom{align-items:flex-start;flex-direction:column;gap:6px}}
@media(max-width:430px){.hero-actions .button{width:100%}.formula-chip-row{grid-template-columns:1fr}.calculator-card{padding:17px}.form-actions{grid-template-columns:1fr}.result-panel{padding:18px}.chart-head{flex-direction:column}.related-card{grid-template-columns:44px minmax(0,1fr) auto;padding:16px}.related-icon{width:44px;height:44px}.footer-grid{grid-template-columns:1fr}.footer-grid>div:first-child{grid-column:auto}}
@media print{.site-header,.hero-actions,.hero-points,.calculator-sidebar,.guide-section,.knowledge-section,.related-section,.site-footer,.text-button,.form-actions,.icon-button{display:none!important}body{background:#fff}.hero,.calculator-section{padding:20px 0;background:#fff}.hero-grid,.calculator-layout{display:block}.formula-stage{margin-top:20px;box-shadow:none}.calculator-card{padding:0;border:0;box-shadow:none}.result-panel{break-inside:avoid}}
@media(prefers-reduced-motion:reduce){*,*::before,*::after{scroll-behavior:auto!important;animation-duration:.01ms!important;animation-iteration-count:1!important;transition-duration:.01ms!important}}