:root{color:#1f2328;-webkit-font-smoothing:antialiased;-moz-osx-font-smoothing:grayscale;text-rendering:optimizelegibility;background-color:#f6f8fa;font-family:system-ui,-apple-system,Segoe UI,Roboto,sans-serif;font-size:16px;line-height:1.5}*{box-sizing:border-box}body{min-height:100vh;margin:0}#app{justify-content:center;align-items:flex-start;min-height:100vh;padding:24px;display:flex}.app-shell{flex-direction:column;gap:16px;width:100%;max-width:760px;display:flex}.calculator{background:#fff;border:1px solid #d0d7de;border-radius:12px;width:100%;max-width:360px;padding:20px;box-shadow:0 4px 16px #1f23280f}@media (width>=720px){.app-shell{flex-direction:row;align-items:flex-start}.calculator{flex:0 0 360px}}.calculator__title{color:#57606a;text-align:center;letter-spacing:.02em;margin:0 0 12px;font-size:18px;font-weight:600}.calculator__hint{color:#6e7781;text-align:center;margin:12px 0 0;font-size:12px}.display{background:#1f2328;border-radius:8px;flex-direction:column;justify-content:center;gap:4px;min-height:96px;margin-bottom:16px;padding:16px 18px;display:flex}.display__expression{color:#f6f8fa;text-align:right;white-space:nowrap;letter-spacing:.02em;width:100%;font-family:ui-monospace,SFMono-Regular,Consolas,monospace;font-size:28px;font-weight:500;overflow-x:auto}.display__result{color:#c9d1d9;text-align:right;white-space:nowrap;width:100%;font-family:ui-monospace,SFMono-Regular,Consolas,monospace;font-size:18px;font-weight:500;overflow-x:auto}.display__loading{color:#9ca3af;text-align:right;font-size:14px;font-style:italic}.display__error{color:#ff8182;text-align:right;word-break:break-word;font-size:14px}.keypad{grid-template-columns:repeat(4,1fr);gap:8px;display:grid}.keypad__button{appearance:none;color:#1f2328;font:inherit;cursor:pointer;touch-action:manipulation;-webkit-user-select:none;user-select:none;background:#f6f8fa;border:1px solid #d0d7de;border-radius:8px;height:56px;font-size:20px;font-weight:500;transition:background-color .12s,border-color .12s,box-shadow .12s,opacity .12s}.keypad__button:hover:not(:disabled){background:#eaeef2}.keypad__button:active:not(:disabled){background:#d8dee4}.keypad__button:focus-visible{outline-offset:2px;outline:2px solid #0969da}.keypad__button:disabled{opacity:.55;cursor:not-allowed}.keypad__button--operator{color:#0969da;background:#ddf4ff;border-color:#b6e3ff;font-weight:600}.keypad__button--operator:hover:not(:disabled){background:#b6e3ff}.keypad__button--equals{color:#fff;background:#2da44e;border-color:#2c974b;font-weight:700}.keypad__button--equals:hover:not(:disabled){background:#2c974b}.keypad__button--utility{color:#57410a;background:#fff8c5;border-color:#d4a72c;font-weight:600}.keypad__button--utility:hover:not(:disabled){background:#fae17d}.keypad__button--paren{color:#57606a;background:#f6f8fa}.history{background:#fff;border:1px solid #d0d7de;border-radius:12px;flex-direction:column;flex:auto;width:100%;min-width:0;max-height:540px;padding:20px;display:flex;box-shadow:0 4px 16px #1f23280f}.history__title{color:#57606a;letter-spacing:.02em;margin:0 0 12px;font-size:16px;font-weight:600}.history__status{color:#57606a;margin:8px 0;font-size:14px;font-style:italic}.history__status--error{color:#cf222e;font-style:normal}.history__status--inline{margin-top:12px}.history__list{flex:auto;min-height:0;margin:0;padding:0;list-style:none;overflow-y:auto}.history__item{border-bottom:1px solid #eaeef2;justify-content:space-between;align-items:flex-start;gap:12px;padding:10px 12px;display:flex}.history__item:last-child{border-bottom:none}.history__item--deleting{opacity:.65}.history__item-body{flex:auto;min-width:0}.history__expression{color:#1f2328;word-break:break-all;font-family:ui-monospace,SFMono-Regular,Consolas,monospace;font-size:15px}.history__result{color:#2da44e;word-break:break-all;margin-top:2px;font-family:ui-monospace,SFMono-Regular,Consolas,monospace;font-size:14px}.history__time{color:#6e7781;margin-top:4px;font-size:12px}.history__delete{appearance:none;color:#cf222e;font:inherit;cursor:pointer;white-space:nowrap;background:#fff;border:1px solid #d0d7de;border-radius:6px;flex:none;align-self:center;padding:6px 10px;font-size:12px;font-weight:600;transition:background-color .12s,border-color .12s,opacity .12s}.history__delete:hover:not(:disabled){background:#fff5f5;border-color:#cf222e}.history__delete:focus-visible{outline-offset:2px;outline:2px solid #0969da}.history__delete:disabled{opacity:.55;cursor:not-allowed}@media (width<=480px){.calculator{padding:16px}.display{min-height:88px;padding:14px}.display__expression{font-size:24px}.display__result{font-size:16px}.keypad__button{height:52px;font-size:18px}.history{max-height:none;padding:16px}}@media (width<=360px){.keypad__button{height:48px;font-size:16px}}