.tool-hero{display: flex;flex-wrap:wrap;gap:32px;align-items:flex-start;margin-bottom:1rem;}
.hero-text{flex:1;min-width:260px;}
.hero-text h1{font-size:40px;font-weight:700;line-height:1.2;margin-bottom:0;}
.hero-subtitle{font-size:18px;color:var(--text-muted);max-width:760px;margin-bottom:1rem;margin-top:0;}
@media (max-width:767px){.hero-text h1{font-size:clamp(1.75rem,5vw,2.5rem);}.hero-subtitle{font-size:clamp(1rem,3vw,1.125rem);}}
.circ-section{margin-bottom:2rem;}
.circ-card{background:var(--circ-bg,#fff);border:1px solid var(--circ-border,#e5e7eb);border-radius:20px;box-shadow:0 8px 32px rgba(0,0,0,0.06);overflow:hidden;padding:1.5rem;}
.circ-mode{display:flex;gap:0;background:var(--circ-toggle-bg,#f1f5f9);border-radius:12px;padding:4px;margin-bottom:1.25rem;}
.circ-mode-btn{flex:1;padding:0.75rem 1rem;font-size:0.9375rem;font-weight:600;color:var(--circ-muted,#64748b);background:transparent;border:none;border-radius:10px;cursor:pointer;transition:color 0.2s,background 0.2s;-webkit-tap-highlight-color:transparent;}
.circ-mode-btn:hover{color:var(--circ-text,#0f172a);}
.circ-mode-btn.is-active{background:var(--circ-active-bg,#fff);color:var(--circ-active,#0f172a);box-shadow:0 2px 8px rgba(0,0,0,0.06);}
.circ-input-wrap{display:flex;flex-direction:column;gap:0.5rem;margin-bottom:1.5rem;}
.circ-label{font-size:0.875rem;font-weight:600;color:var(--circ-muted,#64748b);}
.circ-input{width:100%;max-width:100%;padding:1rem 1.25rem;font-size:1.25rem;font-variant-numeric:tabular-nums;border:2px solid var(--circ-border,#e5e7eb);border-radius:12px;background:var(--circ-input-bg,#fff);transition:border-color 0.2s,box-shadow 0.2s;-webkit-appearance:none;appearance:none;}
.circ-input:focus{outline:none;border-color:var(--circ-focus,#3b82f6);box-shadow:0 0 0 4px rgba(59,130,246,0.15);}
.circ-input::placeholder{color:var(--circ-placeholder,#94a3b8);}
.circ-results{display:grid;grid-template-columns:1fr 1fr;gap:0.75rem;}
.circ-result{display:flex;flex-direction:column;gap:0.25rem;padding:1rem;background:var(--circ-result-bg,#f8fafc);border-radius:12px;border:1px solid var(--circ-border,#e5e7eb);min-height:4rem;justify-content:center;}
.circ-result-name{font-size:0.75rem;font-weight:600;color:var(--circ-muted,#64748b);text-transform:uppercase;letter-spacing:0.05em;}
.circ-result-num{font-size:1.25rem;font-weight:700;color:var(--circ-value,#0f172a);font-variant-numeric:tabular-nums;}
.circ-formulas{margin:1rem 0 0;padding-top:1rem;font-size:0.8125rem;color:var(--circ-muted,#64748b);line-height:1.5;border-top:1px solid var(--circ-border,#e5e7eb);}
@media (min-width:480px){.circ-results{grid-template-columns:repeat(4,1fr);}.circ-result-num{font-size:1.375rem;}}
@media (min-width:768px){.circ-card{padding:2rem;}.circ-mode{margin-bottom:1.5rem;}.circ-input-wrap{margin-bottom:1.75rem;}.circ-input{font-size:1.5rem;padding:1.25rem 1.5rem;}.circ-result-num{font-size:1.5rem;}.circ-result{padding:1.25rem;}}