:root{color-scheme:light dark;--bg:#f6f3ec;--ink:#273b35;--muted:#64716a;--line:#dedfd4;--surface:#fffcf7;--accent:#a34c2d;--selected:#273f36;--selected-text:#fffdf7;--receipt:#e5ebdd;--error:#a02c27;--focus:#bd643e}*{box-sizing:border-box}body{margin:0;background:var(--bg);color:var(--ink);font-family:Inter,ui-sans-serif,system-ui,-apple-system,BlinkMacSystemFont,"Segoe UI",sans-serif;min-height:100svh;display:grid;place-items:center;padding:72px 24px}button,input{font:inherit;color:inherit}button{cursor:pointer}button:focus-visible,input:focus-visible{outline:3px solid var(--focus);outline-offset:4px}[hidden]{display:none!important}#auth-area{position:absolute;top:16px;right:20px}main{width:min(100%,800px)}.heading{display:flex;align-items:center;justify-content:space-between;margin-bottom:32px}.brand{font-size:11px;letter-spacing:3px;font-weight:800;color:var(--accent)}h1{font-family:Georgia,'Times New Roman',serif;font-size:52px;font-weight:400;letter-spacing:-2px;margin:10px 0 0}.reset{border:0;background:transparent;color:var(--muted);font-size:14px;padding:12px}.reset span{margin-left:10px;font-size:23px}.calculator{display:grid;grid-template-columns:1fr 1fr;border:1px solid var(--line);border-radius:22px;background:var(--surface);box-shadow:0 12px 45px #263b3510;overflow:hidden}form{padding:36px;min-width:0}label,legend{font-size:14px;font-weight:650}fieldset{border:0;padding:0;margin:28px 0}legend{padding:0;margin-bottom:14px}.money-input{display:flex;align-items:center;gap:12px;border:1px solid var(--line);background:var(--bg);border-radius:10px;padding:15px 18px;margin-top:12px}.money-input span{font-size:23px;color:var(--muted)}input{min-width:0;width:100%;background:transparent;border:0;outline-offset:6px;font-variant-numeric:tabular-nums}.money-input input{font-size:30px;font-weight:550}input::placeholder{color:var(--muted);opacity:1}.presets{display:grid;grid-template-columns:repeat(4,1fr);gap:8px}.presets button{background:var(--bg);border:1px solid var(--line);border-radius:8px;padding:12px 0;font-size:15px;font-weight:650}.presets button[aria-pressed=true]{background:var(--selected);color:var(--selected-text);border-color:var(--selected)}.presets button:hover,.stepper button:hover{box-shadow:inset 0 0 0 2px var(--focus)}.custom-tip{display:flex;align-items:center;justify-content:space-between;margin-top:14px}.custom-tip label{font-size:13px;font-weight:400;color:var(--muted)}.small-input{width:93px;display:flex;gap:4px;border:1px solid var(--line);border-radius:7px;padding:8px 10px;background:var(--surface)}.small-input input{text-align:right}.small-input span{color:var(--muted)}.split{display:flex;justify-content:space-between;align-items:center;border-top:1px solid var(--line);padding-top:24px;gap:10px}.split label span{display:block;font-weight:400;color:var(--muted);font-size:12px;margin-top:5px}.stepper{display:flex;align-items:center;width:125px;border:1px solid var(--line);border-radius:9px;overflow:hidden}.stepper button{border:0;background:var(--bg);height:40px;min-width:35px;font-size:22px}.stepper button:disabled{opacity:.45;cursor:default}.stepper input{text-align:center;font-weight:650;width:53px}.error{font-size:12px;color:var(--error);line-height:1.5;margin:14px 0 0}.error:empty{display:none}.receipt{background:var(--receipt);padding:45px 34px 26px;display:flex;flex-direction:column;min-width:0}.receipt-label{font-size:10px;font-weight:750;letter-spacing:2px;color:var(--muted)}.amount{display:block;font-family:Georgia,'Times New Roman',serif;letter-spacing:-2px;font-size:clamp(28px,5vw,55px);margin-top:14px;overflow-wrap:anywhere;line-height:1.2}.split-note{font-size:12px;line-height:1.5;color:var(--muted);margin:10px 0 0}.receipt-rule{border-top:1px dashed var(--muted);opacity:.45;margin:28px 0 22px}dl{margin:0;font-size:14px}dl div{display:flex;justify-content:space-between;gap:12px;margin-bottom:16px}dt{color:var(--muted)}dd{margin:0;font-variant-numeric:tabular-nums;overflow-wrap:anywhere;text-align:right}.total{border-top:1px solid var(--line);padding-top:18px;margin-top:20px;font-weight:650}.total dt{color:var(--ink)}.receipt-footer{border-top:1px solid var(--line);padding-top:18px;margin-top:auto;font-size:12px;color:var(--muted);display:flex;align-items:center;gap:8px}.receipt-footer>span:first-child{font-size:11px;border:1px solid var(--muted);border-radius:50%;width:17px;height:17px;display:grid;place-items:center}.login{text-align:center}.login h1{margin-bottom:26px}@media(max-width:650px){body{padding:82px 18px 32px;align-items:start}.heading{margin-bottom:24px}h1{font-size:43px}.calculator{grid-template-columns:1fr}form{padding:26px}.receipt{padding:28px 26px}.amount{font-size:48px}.receipt-footer{margin-top:14px}.receipt-rule{margin:20px 0}.total{margin-bottom:0}}@media(prefers-color-scheme:dark){:root{--bg:#171e1b;--ink:#ecede4;--muted:#b4beb3;--line:#3f4d41;--surface:#202b24;--accent:#f0aa86;--selected:#c9d9b6;--selected-text:#172319;--receipt:#2c3a2e;--error:#ffb3a9;--focus:#e4a47b}}@media(prefers-reduced-motion:no-preference){button{transition:background .15s,box-shadow .15s}}