/* Bright playful: cream paper, flat bright colours, thick ink outlines, hard offset shadows. */
:root{
  --bg:#fff6e0;--card:#ffffff;--ink:#16120e;--text:#16120e;--muted:#4f4639;--line:#16120e;
  --yellow:#ffd23f;--pink:#ff6b9d;--green:#2bd67b;--blue:#3b5bdb;--sky:#7ab8ff;--orange:#ff8a3d;--purple:#9b6bff;
  --yellow-soft:#fff0b8;--pink-soft:#ffe0ec;--green-soft:#d9f9e6;--blue-soft:#e3eaff;--orange-soft:#ffe6d3;--purple-soft:#eee5ff;
  --brand:#3b5bdb;--good:#0b7a43;--first:#2f47b8;--second:#b45309;--low:#4f4639;
  --b:2.5px solid var(--ink);--sh:5px 5px 0 var(--ink);--sh-lg:8px 8px 0 var(--ink);
  --radius:18px;--max:940px;
  --display:"Bricolage Grotesque",system-ui,-apple-system,"Segoe UI",Roboto,Arial,sans-serif;
  --body:"DM Sans",system-ui,-apple-system,"Segoe UI",Roboto,"Noto Sans",Arial,sans-serif;
  --lcd:"Share Tech Mono",ui-monospace,Menlo,Consolas,monospace;
  color-scheme:light;
}
*{box-sizing:border-box}
html{-webkit-text-size-adjust:100%;scroll-behavior:smooth}
body{margin:0;background:var(--bg);color:var(--text);font:16.5px/1.7 var(--body);
  background-image:radial-gradient(rgba(22,18,14,.07) 1.2px,transparent 1.3px);background-size:22px 22px}
a{color:var(--blue);font-weight:600;text-decoration-thickness:2px;text-underline-offset:3px}
a:hover{color:var(--ink);background:var(--yellow)}
img{max-width:100%}
.wrap{max-width:var(--max);margin:0 auto;padding-left:max(16px,env(safe-area-inset-left,0px));padding-right:max(16px,env(safe-area-inset-right,0px))}

/* header */
header.site{background:var(--card);border-bottom:var(--b);position:sticky;top:0;z-index:20}
header.site .wrap{display:flex;align-items:center;justify-content:space-between;gap:10px;min-height:62px;flex-wrap:wrap}
.logo{font:800 1.25rem var(--display);text-decoration:none;color:var(--ink);letter-spacing:-.01em;display:inline-flex;align-items:center;gap:5px}
.logo:hover{background:none;color:var(--ink)}
.logo span{background:var(--pink);color:var(--ink);border:var(--b);border-radius:10px;padding:0 7px;box-shadow:3px 3px 0 var(--ink);transform:rotate(-4deg);transition:transform .25s cubic-bezier(.3,1.8,.5,1)}
.logo:hover span{transform:rotate(4deg) scale(1.08)}
nav.top{display:flex;gap:6px;flex-wrap:nowrap;overflow-x:auto;font-size:.92rem;scrollbar-width:none;max-width:100%;padding:4px 4px 6px}
nav.top::-webkit-scrollbar{display:none}
nav.top a{text-decoration:none;color:var(--ink);padding:6px 13px;border-radius:999px;white-space:nowrap;font-weight:700;border:2px solid transparent;transition:transform .15s,background .15s}
nav.top a:hover{background:var(--yellow-soft);border-color:var(--ink);transform:translateY(-2px)}
nav.top a.on{background:var(--yellow);border-color:var(--ink);box-shadow:3px 3px 0 var(--ink)}

/* hero */
.hero{background:var(--yellow);border-bottom:var(--b);padding-block:6px 46px;position:relative;overflow:hidden}
.hero::before,.hero::after{content:"";position:absolute;pointer-events:none;border:var(--b)}
.hero::before{width:120px;height:120px;border-radius:50%;background:var(--pink);right:6%;top:-40px;animation:float 7s ease-in-out infinite}
.hero::after{width:70px;height:70px;border-radius:16px;background:var(--green);right:22%;top:28px;transform:rotate(14deg);animation:spin 18s linear infinite}
.hero .wrap{position:relative;z-index:1}
.hero h1,.hero .lead{animation:rise .6s cubic-bezier(.2,.9,.3,1.2) both}
.hero .lead{animation-delay:.1s;color:var(--ink);font-weight:500}
.crumbs{font-size:.86rem;margin:14px 0 0;font-weight:600}
.crumbs a{color:var(--ink)}
main{padding-bottom:50px}
h1{font:800 clamp(2rem,5.6vw,3rem)/1.08 var(--display);letter-spacing:-.03em;margin:18px 0 10px;text-wrap:balance;max-width:20ch}
h2{font:800 1.6rem/1.2 var(--display);letter-spacing:-.02em;margin:48px 0 14px;text-wrap:balance}
h2::after{content:"";display:block;width:64px;height:8px;margin-top:8px;border-radius:99px;background:var(--pink);border:2px solid var(--ink)}
main .wrap>h2:nth-of-type(3n+2)::after{background:var(--green)}
main .wrap>h2:nth-of-type(3n)::after{background:var(--sky)}
h3{font:700 1.15rem var(--display);margin:22px 0 8px}
p,li{max-width:68ch}
.lead{color:var(--muted);font-size:1.1rem;margin:0 0 6px;max-width:56ch}
.updated{font-size:.85rem;color:var(--muted)}

/* ===== calculator device ===== */
.tool{position:relative;margin:24px 0;padding:22px 20px 20px;border-radius:28px;background:var(--blue);border:var(--b);box-shadow:var(--sh-lg);color:#fff;z-index:2;
  animation:rise .55s cubic-bezier(.2,.9,.3,1.2) .08s both}
.hero+.wrap>.tool:first-child,.hero+.wrap>.answer:first-child{margin-top:-30px}
.tool::before{content:"CGPA-2026";position:absolute;top:8px;right:22px;font:700 .7rem var(--lcd);letter-spacing:.14em;color:rgba(255,255,255,.75)}
.tool label{color:#fff;font-weight:700}
.tool .small{color:#e3eaff}
.screen{position:relative;margin:10px 0 16px;padding:12px 16px 10px;border-radius:14px;min-height:98px;overflow:hidden;
  background:#c9f27b;border:var(--b);box-shadow:inset 4px 4px 0 rgba(0,0,0,.12);font-family:var(--lcd);color:#1d2a0c}
.scr-top{display:flex;justify-content:space-between;gap:8px;font-size:.82rem;letter-spacing:.06em;text-transform:uppercase;opacity:.7;white-space:nowrap;overflow:hidden}
.scr-top b{font-weight:400;overflow:hidden;text-overflow:ellipsis}
.scr-main{font-size:clamp(2.2rem,8vw,3rem);line-height:1.15;text-align:right;letter-spacing:.03em;white-space:nowrap;overflow:hidden;text-overflow:ellipsis;font-variant-numeric:tabular-nums}
.scr-main.blink::after{content:"_";animation:blink 1s steps(1) infinite}
.scr-main.flash{animation:lcd .45s ease}
.calc-body{display:grid;grid-template-columns:1fr;gap:16px}
@media (min-width:700px){.calc-body{grid-template-columns:1fr 250px;align-items:start}}
.calc-fields{min-width:0}
.calc-fields .row{grid-template-columns:repeat(auto-fit,minmax(220px,1fr))}
.row{display:grid;grid-template-columns:repeat(auto-fit,minmax(180px,1fr));gap:14px}
label{display:block;font-weight:700;font-size:.93rem;margin-bottom:6px}
input,select{width:100%;padding:12px 14px;border:var(--b);border-radius:14px;background:var(--card);color:var(--ink);font:500 1.05rem var(--body);transition:box-shadow .15s,transform .15s}
.tool input{font:700 1.25rem var(--lcd)}
.tool select:disabled{opacity:.6}
input::placeholder{color:#8a8070}
input:focus,select:focus{outline:none;box-shadow:4px 4px 0 var(--ink);transform:translate(-2px,-2px)}
.tool input.active{background:var(--yellow-soft);box-shadow:4px 4px 0 var(--ink);transform:translate(-2px,-2px)}

/* sliders */
.slide{margin-top:12px;display:flex;align-items:center;gap:8px;font:700 .78rem var(--lcd);color:#fff}
input[type=range]{-webkit-appearance:none;appearance:none;padding:0;height:14px;border:2px solid var(--ink);border-radius:99px;flex:1;cursor:pointer;font-size:0;box-shadow:none;transform:none;
  background:linear-gradient(90deg,var(--pink) var(--p,50%),#fff var(--p,50%))}
input[type=range]:focus{box-shadow:0 0 0 3px var(--yellow);transform:none}
input[type=range]::-webkit-slider-thumb{-webkit-appearance:none;width:28px;height:28px;border-radius:50%;background:var(--yellow);border:2.5px solid var(--ink);box-shadow:2px 2px 0 var(--ink);transition:transform .12s}
input[type=range]:active::-webkit-slider-thumb{transform:scale(1.2)}
input[type=range]::-moz-range-thumb{width:22px;height:22px;border-radius:50%;background:var(--yellow);border:2.5px solid var(--ink)}

/* keypad */
.pad{touch-action:manipulation;-webkit-user-select:none;user-select:none;-webkit-tap-highlight-color:transparent;display:grid;grid-template-columns:repeat(4,1fr);gap:10px;padding:12px;border-radius:20px;background:#2f47b8;border:var(--b)}
.pad button{padding:0;height:50px;border-radius:14px;font:700 1.3rem var(--lcd);color:var(--ink);background:#fff;border:var(--b);box-shadow:3px 4px 0 var(--ink);transition:transform .05s,box-shadow .05s}
.pad button:not([class]):hover{background:var(--yellow-soft)}
.pad button:active,.pad button.hit{transform:translate(3px,4px);box-shadow:0 0 0 var(--ink)}
.pad .k-del,.pad .k-clr{background:var(--orange)}
.pad .k-del{font:700 1.35rem var(--body)}
.pad .k-next{background:var(--green);font-size:1.05rem}
.pad .k-eq{grid-column:span 2;background:var(--pink);font-size:1.6rem}
.pad .k-del:hover,.pad .k-clr:hover,.pad .k-next:hover,.pad .k-eq:hover{filter:brightness(1.06)}

/* buttons */
.btns{display:flex;gap:12px;margin-top:18px;flex-wrap:wrap}
button{touch-action:manipulation;cursor:pointer;border:var(--b);border-radius:14px;padding:12px 22px;font:800 1.02rem var(--body);background:var(--yellow);color:var(--ink);
  box-shadow:4px 4px 0 var(--ink);transition:transform .08s,box-shadow .08s}
button:hover{transform:translate(-1px,-1px);box-shadow:5px 5px 0 var(--ink)}
button:active{transform:translate(4px,4px);box-shadow:0 0 0 var(--ink)}
.btns button[type=submit]{flex:1 1 200px;font-size:1.1rem}
button.ghost{background:#fff;color:var(--ink)}
button:focus-visible,a:focus-visible{outline:3px dashed var(--ink);outline-offset:3px}

.chips{display:flex;flex-wrap:wrap;gap:8px;margin-top:16px}
.chips span{font-size:.88rem;font-weight:700;color:#fff;align-self:center}
.chip{font:700 .92rem var(--lcd);padding:5px 14px;border-radius:999px;background:#fff;color:var(--ink);text-decoration:none;border:2px solid var(--ink);box-shadow:2px 2px 0 var(--ink);transition:transform .12s}
.chip:hover{background:var(--yellow);transform:translateY(-2px) rotate(-3deg)}

.sem{display:grid;grid-template-columns:1fr 1fr auto;gap:8px;align-items:end;margin-bottom:10px;animation:rise .3s ease both}
.sem button{padding:11px 14px;background:#fff}

/* result slip */
.result{position:relative;margin-top:20px;padding:20px 18px;border-radius:20px;background:#fff;color:var(--ink);border:var(--b);box-shadow:var(--sh);display:none;text-align:center;overflow:hidden}
.result.show{display:block}
.result.anim{animation:pop .5s cubic-bezier(.2,1.5,.4,1)}
.result.good{background:var(--green-soft)}.result.good .big{color:var(--good)}
.result.first{background:var(--blue-soft)}.result.first .big{color:var(--first)}
.result.second{background:var(--orange-soft)}.result.second .big{color:var(--second)}
.result.low{background:#fff}.result.low .big{color:var(--low)}
.result .emo{font-size:2.8rem;line-height:1;display:inline-block}
.result.anim .emo{animation:bounce .8s ease .15s}
.result .big{font:800 clamp(2.6rem,9vw,3.8rem)/1.05 var(--display);letter-spacing:-.03em;margin-top:6px;font-variant-numeric:tabular-nums}
.result .tag{display:inline-block;margin-top:8px;font-weight:800;padding:4px 14px;border-radius:999px;background:var(--yellow);border:2px solid var(--ink);transform:rotate(-2deg)}
.result .sub{color:var(--muted);font-size:.94rem;margin-top:10px}
.result .meter{height:16px;border-radius:99px;background:#fff;border:2px solid var(--ink);margin:14px auto 0;max-width:380px;overflow:hidden}
.result .meter i{display:block;height:100%;width:0;background:repeating-linear-gradient(-45deg,var(--pink) 0 10px,#ff8db5 10px 20px);border-right:2px solid var(--ink);transition:width .9s cubic-bezier(.2,.9,.3,1)}
.result .share{display:flex;gap:10px;justify-content:center;flex-wrap:wrap;margin-top:14px}
.result .share button,.result .share a{font:700 .88rem var(--body);padding:7px 14px;border-radius:999px;background:#fff;color:var(--ink);border:2px solid var(--ink);text-decoration:none;box-shadow:2px 2px 0 var(--ink)}
.result .share a:hover,.result .share button:hover{background:var(--yellow)}
.confetti{position:absolute;inset:0;pointer-events:none}
.confetti i{position:absolute;top:-12px;width:9px;height:14px;border-radius:2px;border:1.5px solid var(--ink);opacity:0;animation:fall 1.6s ease-in forwards}

@keyframes pop{0%{transform:scale(.8) rotate(-2deg);opacity:0}100%{transform:none;opacity:1}}
@keyframes bounce{0%,100%{transform:translateY(0)}30%{transform:translateY(-14px) rotate(-10deg)}60%{transform:translateY(0) rotate(8deg)}}
@keyframes rise{from{opacity:0;transform:translateY(20px)}to{opacity:1;transform:none}}
@keyframes float{0%,100%{transform:translateY(0)}50%{transform:translateY(16px)}}
@keyframes spin{to{transform:rotate(374deg)}}
@keyframes blink{50%{opacity:0}}
@keyframes lcd{0%{opacity:.25}35%{opacity:1}50%{opacity:.6}100%{opacity:1}}
@keyframes fall{0%{opacity:1;transform:translateY(0) rotate(0)}100%{opacity:0;transform:translateY(260px) rotate(540deg)}}
@keyframes shake{20%,60%{transform:translateX(-7px)}40%,80%{transform:translateX(7px)}}
.shake{animation:shake .4s ease}
.err{color:#c81e4a;font-weight:800}

/* content blocks */
.note{background:var(--pink-soft);border:var(--b);box-shadow:var(--sh);padding:14px 16px;border-radius:16px;margin:20px 0;font-size:.96rem}
.tip{background:var(--yellow-soft);border:var(--b);box-shadow:var(--sh);border-radius:16px;padding:14px 16px;margin:20px 0}
.formula{font:700 1.15rem var(--lcd);background:#c9f27b;color:#1d2a0c;border:var(--b);box-shadow:var(--sh);border-radius:14px;padding:14px 18px;overflow-x:auto}
.answer{background:#fff;border:var(--b);box-shadow:var(--sh-lg);border-radius:24px;padding:22px;margin:24px 0;position:relative;z-index:2;animation:rise .55s cubic-bezier(.2,.9,.3,1.2) .08s both}
.answer .big{font:800 clamp(2rem,7vw,3rem)/1.12 var(--display);letter-spacing:-.03em}
.answer .big b{background:var(--yellow);padding:0 8px;border-radius:10px;border:2px solid var(--ink);display:inline-block;transform:rotate(-1.5deg)}
.answer p{margin:8px 0 0;color:var(--muted)}
.tablewrap{overflow-x:auto;margin:16px 0;border:var(--b);border-radius:16px;background:#fff;box-shadow:var(--sh)}
table{border-collapse:collapse;width:100%;font-size:.96rem;font-variant-numeric:tabular-nums}
th,td{padding:11px 13px;border-bottom:2px solid var(--ink);text-align:left;white-space:nowrap}
th{background:var(--yellow);color:var(--ink);font-weight:800}
th a{color:var(--ink)}
tbody tr:nth-child(even) td{background:#fffaf0}
tbody tr:hover td{background:var(--blue-soft)}
tr:last-child td{border-bottom:0}
td.wrap,th.wrap{white-space:normal;min-width:180px}
.grid-links{display:grid;grid-template-columns:repeat(auto-fit,minmax(190px,1fr));gap:14px;margin:16px 0;padding:0;list-style:none}
.grid-links li{max-width:none}
.grid-links a{display:flex;align-items:center;justify-content:space-between;gap:8px;height:100%;padding:14px 16px;border:var(--b);border-radius:16px;text-decoration:none;color:var(--ink);font-weight:700;
  background:#fff;box-shadow:4px 4px 0 var(--ink);transition:transform .15s cubic-bezier(.3,1.6,.5,1),box-shadow .15s}
.grid-links li:nth-child(5n+1) a{background:var(--pink-soft)}
.grid-links li:nth-child(5n+2) a{background:var(--green-soft)}
.grid-links li:nth-child(5n+3) a{background:var(--blue-soft)}
.grid-links li:nth-child(5n+4) a{background:var(--yellow-soft)}
.grid-links li:nth-child(5n+5) a{background:var(--purple-soft)}
.grid-links a::after{content:"→";font-weight:800;transition:transform .15s}
.grid-links a:hover{transform:translate(-2px,-3px) rotate(-1deg);box-shadow:7px 7px 0 var(--ink)}
.grid-links a:hover::after{transform:translateX(4px)}
details{background:#fff;border:var(--b);border-radius:16px;padding:13px 18px;margin:12px 0;box-shadow:3px 3px 0 var(--ink);transition:box-shadow .15s}
details[open]{background:var(--yellow-soft);box-shadow:var(--sh)}
summary{cursor:pointer;font-weight:800;list-style:none;display:flex;justify-content:space-between;gap:12px}
summary::-webkit-details-marker{display:none}
summary::after{content:"+";flex:none;width:28px;height:28px;display:grid;place-items:center;border:2px solid var(--ink);border-radius:50%;background:var(--pink);font:800 1.1rem/1 var(--display);transition:transform .25s}
details[open] summary::after{transform:rotate(45deg)}
details[open] p{animation:rise .3s ease}
details p{margin:10px 0 0}
.toc{background:#fff;border:var(--b);border-radius:16px;padding:13px 18px;margin:20px 0;box-shadow:var(--sh)}
.toc b{display:block;margin-bottom:4px}
.toc ol{margin:0;padding-left:20px}
ul li::marker{color:var(--pink)}

/* scroll reveal (only when JS runs) */
.js .rv{opacity:0;transform:translateY(24px);transition:opacity .5s ease,transform .5s cubic-bezier(.2,.9,.3,1.2)}
.js .rv.in{opacity:1;transform:none}

footer.site{background:var(--ink);color:#e9dfc9;padding-block:32px;font-size:.92rem;border-top:var(--b)}
footer.site .cols{display:grid;grid-template-columns:repeat(auto-fit,minmax(160px,1fr));gap:16px}
footer.site h4{margin:0 0 8px;color:var(--yellow);font:800 1.02rem var(--display)}
footer.site ul{list-style:none;margin:0;padding:0}
footer.site li{margin:4px 0}
footer.site a{color:#e9dfc9;text-decoration:none;font-weight:500}
footer.site a:hover{color:var(--ink);background:var(--yellow)}
footer.site .small{color:#bfb39b}
.small{font-size:.88rem;color:var(--muted)}

@media (max-width:520px){
  .tool{padding:22px 14px 16px;border-radius:24px}
  .pad button{height:54px}
  .sem{grid-template-columns:1fr 1fr 46px}
  .hero::before{width:80px;height:80px;right:-20px}
}
@media (prefers-reduced-motion:reduce){
  *,*::before,*::after{animation:none!important;transition:none!important}
  .js .rv{opacity:1;transform:none}
}

.kbd-tip{grid-column:1/-1;margin:0;font-size:.85rem;color:#fff;opacity:.9}
.kbd-tip kbd{font:700 .78rem var(--lcd);background:#fff;color:var(--ink);border:1.5px solid var(--ink);border-radius:6px;padding:1px 6px;box-shadow:1px 2px 0 var(--ink)}
@media (hover:none),(max-width:699px){.kbd-tip{display:none}}