:root{--bg:#eef6ff;--surface:rgba(255,255,255,.7);--surface-strong:rgba(255,255,255,.9);--border:rgba(255,255,255,.8);--text:#16243a;--muted:#64748b;--primary:#1779d4;--primary-dark:#0b5fae;--shadow:0 24px 65px rgba(41,72,112,.14);--radius:26px;--radius-small:16px;--focus:0 0 0 4px rgba(23,121,212,.2)}
[data-theme="dark"]{--bg:#0a1220;--surface:rgba(17,29,48,.72);--surface-strong:rgba(15,26,44,.94);--border:rgba(148,163,184,.18);--text:#eef6ff;--muted:#a8b7cc;--primary:#66b7ff;--primary-dark:#96ceff;--shadow:0 25px 70px rgba(0,0,0,.32);--focus:0 0 0 4px rgba(102,183,255,.22)}
*{box-sizing:border-box}html{scroll-behavior:smooth}body{min-height:100vh;margin:0;color:var(--text);font-family:Inter,ui-sans-serif,system-ui,-apple-system,"Segoe UI",sans-serif;background:linear-gradient(-45deg,#e8f4ff,#f0ecff,#e8fff7,#fff1e8);background-size:400% 400%;animation:gradientShift 18s ease infinite;overflow-x:hidden}body::before{content:"";position:fixed;inset:0;z-index:-2;background:var(--bg);opacity:.18;transition:background .3s ease}[data-theme="dark"] body{background:linear-gradient(-45deg,#07101f,#14102c,#07251e,#23130d);background-size:400% 400%}@keyframes gradientShift{0%{background-position:0 50%}50%{background-position:100% 50%}100%{background-position:0 50%}}button,input,select,textarea{font:inherit}button{color:inherit}a{color:inherit}.shell{width:min(1180px,calc(100% - 40px));margin-inline:auto}.background-orb{position:fixed;z-index:-1;border-radius:50%;filter:blur(4px);opacity:.35;animation:floatOrb 15s ease-in-out infinite alternate}.background-orb--one{width:420px;height:420px;top:-160px;left:-130px;background:radial-gradient(circle,#5fbdff,transparent 68%)}.background-orb--two{width:520px;height:520px;right:-210px;top:24%;background:radial-gradient(circle,#8e79ff,transparent 68%);animation-delay:-5s}.background-orb--three{width:400px;height:400px;left:26%;bottom:-240px;background:radial-gradient(circle,#56e6ba,transparent 68%);animation-delay:-9s}@keyframes floatOrb{to{transform:translate3d(32px,-24px,0) scale(1.08)}}.glass-card{background:var(--surface);border:1px solid var(--border);box-shadow:var(--shadow);backdrop-filter:blur(22px);-webkit-backdrop-filter:blur(22px)}.site-header{display:flex;align-items:center;justify-content:space-between;gap:20px;padding-block:24px}.brand{display:flex;align-items:center;gap:14px;text-decoration:none}.brand__logo{width:58px;height:58px;object-fit:contain;filter:drop-shadow(0 8px 18px rgba(22,36,58,.18))}.brand span{display:grid;gap:2px}.brand strong{font-size:1.08rem}.brand small{color:var(--muted)}.header-actions{display:flex;align-items:center;gap:10px}.button,.icon-button,.mode-button{border:0;cursor:pointer;transition:transform .2s ease,background .2s ease,border-color .2s ease,box-shadow .2s ease}.button:focus-visible,.icon-button:focus-visible,.mode-button:focus-visible,.tool-card:focus-visible,.calculator-display:focus-visible,input:focus,select:focus,textarea:focus{outline:none;box-shadow:var(--focus)}.button{display:inline-flex;align-items:center;justify-content:center;gap:8px;min-height:44px;padding:10px 16px;border-radius:13px;font-weight:700}.button:hover,.icon-button:hover{transform:translateY(-2px)}.button--primary{background:linear-gradient(135deg,var(--primary),var(--primary-dark));color:#fff}.button--ghost,.button--subtle{background:var(--surface);border:1px solid var(--border)}.button--subtle{min-height:38px;padding:7px 12px;font-size:.85rem}.icon-button{width:44px;height:44px;border:1px solid var(--border);border-radius:14px;background:var(--surface);font-size:1.2rem}.page-content{padding-block:28px 30px}.hero{max-width:840px;margin:36px auto 48px;text-align:center}.eyebrow,.section-kicker{margin:0 0 8px;color:var(--primary-dark);font-size:.78rem;font-weight:800;letter-spacing:.13em;text-transform:uppercase}.hero h1{margin:0;font-size:clamp(2.15rem,5vw,4.4rem);line-height:1.04;letter-spacing:-.045em}.hero__text{max-width:760px;margin:22px auto 0;color:var(--muted);font-size:clamp(1rem,2vw,1.15rem);line-height:1.75}.calculator-card{padding:clamp(20px,4vw,40px);border-radius:var(--radius)}.section-heading{display:flex;align-items:flex-start;justify-content:space-between;gap:20px}.section-heading h2{margin:0;font-size:clamp(1.55rem,3vw,2.2rem);letter-spacing:-.025em}.section-heading p:not(.section-kicker){margin:8px 0 0;color:var(--muted)}.section-heading--outside{margin-bottom:22px}.mode-switcher{display:flex;gap:9px;margin:28px 0 22px;padding:6px;border:1px solid var(--border);border-radius:16px;background:rgba(127,146,170,.08);width:max-content;max-width:100%;overflow:auto}.mode-button{padding:10px 16px;border-radius:11px;background:transparent;color:var(--muted);font-weight:750;white-space:nowrap}.mode-button.is-active{background:var(--surface-strong);color:var(--primary-dark);box-shadow:0 8px 18px rgba(30,64,100,.1)}.calculator-layout{display:grid;grid-template-columns:minmax(0,1.45fr) minmax(240px,.55fr);gap:24px}.calculator-main,.history-panel{min-width:0}.calculator-display{display:flex;flex-direction:column;align-items:flex-end;justify-content:center;width:100%;min-height:108px;padding:18px 22px;border:1px solid var(--border);border-radius:20px;background:var(--surface-strong);text-align:right;overflow:hidden;cursor:copy}.calculator-display__expression{width:100%;min-height:22px;color:var(--muted);font-size:.86rem;overflow:hidden;text-overflow:ellipsis;white-space:nowrap}.calculator-display #display-value{max-width:100%;font-size:clamp(1.8rem,5vw,3rem);font-weight:800;letter-spacing:-.035em;overflow:hidden;text-overflow:ellipsis;white-space:nowrap}.calculator-buttons{display:grid;grid-template-columns:repeat(4,1fr);gap:10px;margin-top:14px}.calc-key{min-height:58px;border:1px solid var(--border);border-radius:16px;background:var(--surface-strong);font-size:1.05rem;font-weight:750;cursor:pointer;transition:transform .16s ease,box-shadow .16s ease,background .16s ease}.calc-key:hover{transform:translateY(-2px);box-shadow:0 9px 18px rgba(35,65,100,.1)}.calc-key--operator{color:var(--primary-dark);background:rgba(80,166,245,.13)}.calc-key--action{color:#b23d4a;background:rgba(255,104,118,.11)}.calc-key--equals{color:#fff;background:linear-gradient(135deg,var(--primary),var(--primary-dark));grid-column:span 2}.keyboard-hint{margin:13px 3px 0;color:var(--muted);font-size:.78rem;line-height:1.5}.history-panel{padding:20px;border:1px solid var(--border);border-radius:20px;background:rgba(127,146,170,.07)}.history-panel__heading{display:flex;align-items:baseline;justify-content:space-between;gap:10px;margin-bottom:13px}.history-panel h3{margin:0;font-size:1rem}.history-panel__heading span{color:var(--muted);font-size:.7rem}.history-list{display:grid;gap:8px;max-height:440px;overflow:auto}.history-item{width:100%;padding:11px;border:1px solid transparent;border-radius:12px;background:var(--surface);text-align:left;cursor:pointer}.history-item:hover{border-color:var(--border)}.history-item small{display:block;color:var(--muted);overflow:hidden;text-overflow:ellipsis;white-space:nowrap}.history-item strong{display:block;margin-top:4px;overflow:hidden;text-overflow:ellipsis;white-space:nowrap}.empty-state{margin:auto;color:var(--muted);font-size:.9rem;text-align:center}.tools-section{padding-block:68px 22px}.tools-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:18px}.tool-card{display:grid;grid-template-columns:auto 1fr auto;align-items:center;gap:18px;width:100%;padding:22px;border-radius:22px;color:var(--text);text-align:left;cursor:pointer}.tool-card:hover{transform:translateY(-4px);box-shadow:0 28px 70px rgba(41,72,112,.2)}.tool-card__icon{display:grid;place-items:center;width:58px;height:58px;border-radius:18px;background:var(--surface-strong)}.tool-card__icon img{width:32px;height:32px}.tool-card__content{display:grid;gap:5px}.tool-card__content strong{font-size:1.05rem}.tool-card__content small{color:var(--muted);line-height:1.55}.tool-card__arrow{font-size:1.45rem;color:var(--primary-dark)}.site-footer{padding-block:24px 36px}.footer-box{padding:18px 22px;border-radius:20px;text-align:center}.footer-message{display:inline-block;text-decoration:none;font-weight:650}.footer-message:hover,.footer-meta a:hover{text-decoration:underline}.footer-meta{display:flex;justify-content:center;flex-wrap:wrap;gap:8px;margin-top:10px;color:var(--muted);font-size:.84rem}.modal{position:fixed;inset:0;z-index:100;display:grid;place-items:center;padding:20px}.modal[hidden]{display:none}.modal__backdrop{position:absolute;inset:0;background:rgba(5,12,23,.58);backdrop-filter:blur(9px)}.modal__panel{position:relative;z-index:1;width:min(620px,100%);max-height:min(88vh,900px);overflow:auto;padding:clamp(22px,4vw,34px);border:1px solid var(--border);border-radius:26px;background:var(--surface-strong);box-shadow:0 30px 90px rgba(0,0,0,.32);animation:modalIn .22s ease}.modal__panel--wide{width:min(820px,100%)}@keyframes modalIn{from{opacity:0;transform:translateY(18px) scale(.98)}to{opacity:1;transform:none}}.modal__close{position:absolute;top:14px;right:14px;width:42px;height:42px;border:0;border-radius:13px;background:rgba(127,146,170,.12);font-size:1.6rem;cursor:pointer}.modal__header{padding-right:42px;margin-bottom:22px}.modal__header h2{margin:0;font-size:1.75rem}.modal__header p:not(.section-kicker){margin:8px 0 0;color:var(--muted);line-height:1.6}.form-grid{display:grid;gap:15px}.form-grid--two{grid-template-columns:repeat(2,minmax(0,1fr))}.field{display:grid;gap:7px;font-size:.87rem;font-weight:700}.field input,.field select,.field textarea{width:100%;border:1px solid var(--border);border-radius:13px;background:var(--surface);color:var(--text);padding:12px 13px;resize:vertical}.choice-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:10px;margin-top:15px}.choice-grid label{display:flex;align-items:center;gap:9px;padding:11px;border:1px solid var(--border);border-radius:13px;background:var(--surface);font-size:.9rem}.tool-actions{display:flex;flex-wrap:wrap;gap:10px;margin-top:20px}.result-box{display:block;width:100%;min-height:64px;margin-top:16px;padding:16px;border:1px solid var(--border);border-radius:15px;background:rgba(127,146,170,.09);font-size:1.1rem;font-weight:750}.result-box--break{overflow-wrap:anywhere}.qr-output{display:grid;place-items:center;min-height:260px;margin-top:18px;padding:15px;border:1px solid var(--border);border-radius:18px;background:#fff}.qr-output img{display:block;max-width:100%;height:auto}.privacy-note{color:var(--muted);font-size:.76rem;text-align:center}.help-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:14px}.help-grid section{padding:17px;border:1px solid var(--border);border-radius:16px;background:var(--surface)}.help-grid h3{margin:0 0 7px;font-size:1rem}.help-grid p{margin:0;color:var(--muted);font-size:.88rem;line-height:1.6}.help-grid code{padding:2px 5px;border-radius:5px;background:rgba(127,146,170,.14)}.toast{position:fixed;z-index:200;left:50%;bottom:24px;transform:translate(-50%,20px);padding:11px 16px;border-radius:13px;background:#122138;color:#fff;box-shadow:0 15px 40px rgba(0,0,0,.25);opacity:0;pointer-events:none;transition:.22s ease}.toast.is-visible{opacity:1;transform:translate(-50%,0)}body.modal-open{overflow:hidden}
@media(max-width:820px){.calculator-layout{grid-template-columns:1fr}.history-list{max-height:220px}.tools-grid{grid-template-columns:1fr}.hero{margin-top:20px}.site-header{align-items:flex-start}.brand small{display:none}}
@media(max-width:560px){.shell{width:min(100% - 24px,1180px)}.site-header{padding-block:15px}.brand__logo{width:48px;height:48px}.brand strong{font-size:.98rem}.button--ghost span{display:none}.header-actions .button{padding-inline:12px}.page-content{padding-top:12px}.hero{margin-bottom:34px}.calculator-card{padding:16px;border-radius:21px}.section-heading{align-items:flex-start;flex-direction:column}.mode-switcher{width:100%}.calculator-buttons{gap:7px}.calc-key{min-height:52px;border-radius:13px}.form-grid--two,.choice-grid,.help-grid{grid-template-columns:1fr}.tool-card{padding:17px;gap:13px}.tool-card__icon{width:50px;height:50px}.tool-card__arrow{display:none}.modal{padding:10px}.modal__panel{border-radius:21px}.footer-meta span[aria-hidden="true"]{display:none}}
@media(prefers-reduced-motion:reduce){*,*::before,*::after{scroll-behavior:auto!important;animation-duration:.01ms!important;animation-iteration-count:1!important;transition-duration:.01ms!important}}

/* Extended calculators */
.calculator-panel[hidden]{display:none}.calculator-panel.is-active{animation:panelIn .22s ease}@keyframes panelIn{from{opacity:0;transform:translateY(8px)}to{opacity:1;transform:none}}
.special-calculator{padding:24px;border:1px solid var(--border);border-radius:20px;background:rgba(127,146,170,.06)}.special-calculator__heading{margin-bottom:20px}.special-calculator__heading h3{margin:0;font-size:1.25rem}.special-calculator__heading p{margin:7px 0 0;color:var(--muted)}
.subtabs{display:flex;gap:8px;flex-wrap:wrap;margin-bottom:18px}.subtab{border:1px solid var(--border);border-radius:11px;background:var(--surface);color:var(--muted);padding:9px 13px;font-weight:750;cursor:pointer}.subtab.is-active{background:rgba(80,166,245,.14);color:var(--primary-dark);border-color:rgba(80,166,245,.3)}
.equation-grid{display:grid;grid-template-columns:minmax(90px,1fr) auto minmax(90px,1fr) auto minmax(90px,1fr) auto minmax(32px,.4fr);align-items:end;gap:10px}.equation-grid>span,.equation-grid>strong{padding-bottom:13px;text-align:center;font-size:1.15rem}.field--compact{max-width:280px;margin-top:16px}.health-warning{margin:14px 0 0;padding:12px 14px;border-radius:13px;background:rgba(255,174,66,.12);color:var(--muted);font-size:.82rem;line-height:1.55}
.timer-display{margin:18px 0;padding:20px;border:1px solid var(--border);border-radius:18px;background:rgba(127,146,170,.08);font-variant-numeric:tabular-nums;text-align:center;font-size:clamp(2.2rem,8vw,4.4rem);font-weight:800;letter-spacing:.03em}.laps-list{display:grid;gap:6px;max-height:180px;overflow:auto;margin:16px 0 0;padding-left:28px;color:var(--muted);font-variant-numeric:tabular-nums}
@media(max-width:700px){.equation-grid{grid-template-columns:1fr auto 1fr}.equation-grid label:nth-of-type(3){grid-column:1}.equation-grid>span:nth-of-type(3){grid-column:2}.equation-grid>strong{grid-column:3}.special-calculator{padding:16px}}