*,::after,::before{box-sizing:border-box;margin:0;padding:0}
:root{--mint:#e8f8f2;--green:#2bb87b;--green2:#1a9b63;--teal:#3ecfb2;--navy:#1c2b3a;--ink:#2d3d4e;--muted:#7a8fa0;--border:#d8eae2;--white:#ffffff;--bg:#f4fbf8;--card:#ffffff;--radius:16px;--shadow:0 4px 24px rgba(43,184,123,.10);--font-head:'Lora',Georgia,serif;--font-body:'Plus Jakarta Sans',sans-serif;--primary:#2bb87b;--secondary:#3ecfb2}
html{scroll-behavior:smooth}
body{font-family:var(--font-body);background:var(--bg);color:var(--ink);font-size:16px;line-height:1.65}
header{background:var(--white);border-bottom:1px solid var(--border);position:sticky;top:0;z-index:100}
.header-inner{max-width:1160px;margin:0 auto;padding:0 24px;display:flex;align-items:center;justify-content:space-between;height:60px}
.logo{font-family:var(--font-head);font-size:1.5rem;font-weight:600;color:var(--navy);text-decoration:none;white-space:nowrap;display:flex;align-items:center;gap:8px}
.logo span{color:var(--green)}
.logo-icon{width:32px;height:32px;object-fit:contain;border-radius:6px;transition:transform .35s ease;flex-shrink:0}
.logo:hover .logo-icon{transform:rotateY(180deg)}
nav{display:flex;gap:22px;align-items:center}
nav a{font-size:.88rem;font-weight:500;color:var(--muted);text-decoration:none;transition:color .2s}
nav a:hover{color:var(--green)}
.btn-nav{background:var(--green);color:#fff!important;padding:7px 18px;border-radius:50px;font-size:.82rem!important;transition:background .2s!important}
.btn-nav:hover{background:var(--green2)!important}
.hero-band{background:linear-gradient(135deg,#e0f7ef 0,#f0fdf8 60%,#e6f4ff 100%);padding:34px 24px 26px;text-align:center}
.hero-band h1{font-family:var(--font-head);font-size:clamp(1.7rem,4vw,2.3rem);color:var(--navy);line-height:1.25;max-width:560px;margin:0 auto 9px}
.hero-band p{font-size:.96rem;color:var(--muted);max-width:540px;margin:0 auto}
.badge-row{margin-top:13px;display:flex;justify-content:center;gap:7px;flex-wrap:wrap}
.badge{background:var(--white);border:1px solid var(--border);border-radius:50px;padding:3px 12px;font-size:.75rem;color:var(--green2);font-weight:600}
.container{max-width:1100px;margin:auto;padding:40px 20px}
.section-title{text-align:center;font-size:1.35rem;margin-bottom:20px;font-weight:700;color:var(--navy);font-family:var(--font-head)}
.section-title::after{content:'';display:block;width:34px;height:3px;background:var(--green);border-radius:2px;margin:6px auto 0}
.converter-wrapper{position:relative}
.calc-icon-btn{position:absolute;top:-18px;right:0;background:var(--green);color:#fff;border:none;width:40px;height:40px;border-radius:50%;cursor:pointer;font-size:18px;display:flex;align-items:center;justify-content:center;box-shadow:0 4px 12px rgba(0,0,0,.15);transition:.3s;z-index:10}
.calc-icon-btn:hover{background:var(--teal);transform:scale(1.1)}
.converter-box{background:var(--card);padding:30px;border-radius:var(--radius);box-shadow:var(--shadow);border:1.5px solid var(--border)}
.converter-grid{display:grid;grid-template-columns:1fr 1fr;gap:20px;position:relative}
.field-label{font-weight:700;font-size:12px;color:var(--green2);margin-bottom:6px;text-transform:uppercase;letter-spacing:.6px}
.converter-box input[type=number],.converter-box input[type=text]{width:100%;padding:12px;border-radius:10px;border:1.5px solid var(--border);margin-bottom:10px;font-size:15px;font-family:var(--font-body);color:var(--ink);background:var(--white);transition:border-color .2s}
.converter-box input:focus{outline:0;border-color:var(--teal);box-shadow:0 0 0 3px rgba(62,207,178,.12)}
.converter-box select{width:100%;border-radius:10px;border:1.5px solid var(--border);padding:10px;font-family:var(--font-body);color:var(--ink);background:var(--white);font-size:14px}
.convert-btn{margin-top:15px;padding:12px;background:var(--green);color:#fff;border:none;border-radius:50px;width:100%;cursor:pointer;font-size:15px;font-weight:700;font-family:var(--font-body);transition:.2s;box-shadow:0 4px 16px rgba(43,184,123,.3)}
.convert-btn:hover{background:var(--green2)}
.result-display{margin-top:12px;padding:14px;background:var(--mint);border-radius:10px;border-left:4px solid var(--green);font-size:15px;color:var(--ink);min-height:48px;display:none}
.swap-units-btn{position:absolute;left:50%;top:50%;transform:translate(-50%,-50%);z-index:10;width:42px;height:42px;border-radius:50%;border:2px solid var(--green);background:#fff;color:var(--green);cursor:pointer;display:flex;align-items:center;justify-content:center;padding:0;box-shadow:0 2px 10px rgba(43,184,123,.2);transition:all .25s ease}
.swap-units-btn:hover{background:var(--green);color:#fff;transform:translate(-50%,-50%) scale(1.12) rotate(180deg)}
.swap-units-btn svg{width:20px;height:20px}
.container h2{font-family:var(--font-head);font-size:1.25rem;font-weight:600;color:var(--navy);padding:1.2rem 0 .3rem;border-bottom:2px solid var(--border);margin-bottom:.6rem}
.container p{color:var(--ink);margin-bottom:.9rem;line-height:1.75}
.container ol{padding-left:1.4rem;margin-bottom:.9rem;color:var(--ink);line-height:1.8}
.container ol li{margin-bottom:4px}
.howto-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(260px,1fr));gap:12px;margin-bottom:30px;max-height:380px;overflow:hidden;position:relative}
.howto-grid::after{content:"";position:absolute;bottom:0;left:0;width:100%;height:70px;background:linear-gradient(to bottom,rgba(244,251,248,0),var(--bg));pointer-events:none}
.howto-grid a{background:var(--white);border:1.5px solid var(--border);padding:13px 15px;border-radius:12px;text-decoration:none;color:var(--ink);font-size:.88rem;font-weight:500;transition:all .2s;display:block}
.howto-grid a:hover{background:var(--green);color:#fff;border-color:var(--green);transform:translateY(-2px);box-shadow:var(--shadow)}
.calc-overlay{display:none;position:fixed;inset:0;background:rgba(0,0,0,.55);z-index:1000;align-items:center;justify-content:center;padding:16px}
.calc-overlay.open{display:flex}
.calc-modal{background:#1e1e2e;border-radius:20px;width:100%;max-width:380px;box-shadow:0 20px 60px rgba(0,0,0,.5);overflow:hidden}
.calc-header{display:flex;align-items:center;justify-content:space-between;padding:14px 18px;background:#16162a}
.calc-header span{color:#a0a8c0;font-size:14px;font-weight:600;letter-spacing:.5px}
.calc-close{background:0 0;border:none;color:#a0a8c0;font-size:20px;cursor:pointer;width:30px;height:30px;border-radius:50%;display:flex;align-items:center;justify-content:center;transition:.2s}
.calc-close:hover{background:rgba(255,255,255,.1);color:#fff}
.calc-screen{padding:10px 18px 14px;background:#16162a;border-bottom:1px solid rgba(255,255,255,.05)}
.calc-expr{font-size:12px;color:#6c7a9a;min-height:18px;text-align:right;word-break:break-all;margin-bottom:4px}
.calc-display{font-size:36px;font-weight:300;color:#fff;text-align:right;overflow:hidden;text-overflow:ellipsis;white-space:nowrap;line-height:1.2}
.calc-buttons{display:grid;grid-template-columns:repeat(5,1fr);gap:1px;background:#0e0e1a;padding:1px}
.cb{background:#2a2a40;border:none;color:#fff;padding:0;height:56px;font-size:15px;font-weight:500;cursor:pointer;transition:background .15s;user-select:none}
.cb:active{background:#3a3a55}
.cb.op{background:#1f3050;color:#5dade2}
.cb.op:active{background:#2a4070}
.cb.fn{background:#1a2a1a;color:#4caf50;font-size:13px}
.cb.fn:active{background:#254025}
.cb.eq{background:linear-gradient(135deg,#3ecfb2,#2bb87b);color:#fff;font-size:18px}
.cb.eq:active{opacity:.85}
.cb.clr{background:#3a1a1a;color:#e74c3c}
.cb.clr:active{background:#4a2a2a}
.cb.zero{grid-column:span 2}
footer{background:var(--navy);color:rgba(255,255,255,.55);padding:30px 24px;text-align:center;font-size:.83rem}
footer a{color:rgba(255,255,255,.7);text-decoration:none;margin:0 7px}
footer a:hover{color:var(--teal)}
.footer-logo{font-family:var(--font-head);font-size:1.1rem;color:#fff;margin-bottom:9px;display:block}
.lang-switcher{margin-top:18px;display:flex;flex-direction:column;align-items:center;gap:10px}
.lang-label{font-size:.78rem;color:rgba(255,255,255,.45);font-weight:600;letter-spacing:.04em;text-transform:uppercase}
.lang-list{display:flex;flex-wrap:wrap;justify-content:center;gap:8px}
.lang-item{display:flex;align-items:center;gap:5px;padding:5px 13px;border-radius:50px;border:1.5px solid rgba(255,255,255,.15);background:0 0;color:rgba(255,255,255,.6);font-size:.8rem;font-weight:500;text-decoration:none;transition:all .18s;white-space:nowrap}
.lang-item:hover{border-color:var(--teal);color:var(--teal)}
.lang-item.active{border-color:var(--green);background:var(--green);color:#fff}
.lang-flag{font-size:1rem;line-height:1}
@media(max-width:768px){.converter-grid{grid-template-columns:1fr}
.swap-units-btn{position:static;transform:none;margin:8px auto;display:flex}
nav{gap:14px}
}
@media(max-width:600px){nav .nav-hide{display:none}
.calc-modal{max-width:100%}
.calc-display{font-size:28px}
.cb{height:50px;font-size:14px}
.hero-band{padding:24px 16px 20px}
}