/* ==========================================================================
   Ahsan Ahmed — Android Developer Portfolio
   Design system: Material 3 tonal surfaces, generous rounding, dual theme.
   Type: Bricolage Grotesque (display) / Inter Tight (body) / JetBrains Mono (data)
   ========================================================================== */

:root{
  --f-display:"Bricolage Grotesque","Inter Tight",system-ui,sans-serif;
  --f-body:"Inter Tight",system-ui,-apple-system,"Segoe UI",sans-serif;
  --f-mono:"JetBrains Mono",ui-monospace,"SF Mono",Menlo,monospace;

  --r-xs:10px; --r-s:16px; --r-m:22px; --r-l:30px; --r-xl:40px;

  --w:1180px;
  --pad:clamp(20px,5vw,40px);
  --gap-sec:clamp(72px,11vw,132px);

  --e1:0 1px 2px rgba(8,8,20,.10), 0 1px 3px 1px rgba(8,8,20,.06);
  --e2:0 2px 6px 2px rgba(8,8,20,.08), 0 1px 2px rgba(8,8,20,.10);
  --ease:cubic-bezier(.2,.7,.25,1);
}

/* ---------- dark (default) ---------- */
[data-theme="dark"]{
  --bg:#0D0E15;
  --surf:#14161F;
  --surf2:#1A1D28;
  --surf3:#232636;
  --text:#E9E8F3;
  --text2:#A6A4BD;
  --text3:#7C7A93;
  --line:#2E3145;
  --line2:#3C4058;
  --pri:#B4ABFF;
  --on-pri:#1A0C8E;
  --pri-cont:#2B21A6;
  --on-pri-cont:#E3DFFF;
  --acc:#FFD173;
  --acc-cont:#4A3400;
  --on-acc-cont:#FFE9B8;
  --grid-ink:rgba(180,171,255,.055);
}

/* ---------- light ---------- */
[data-theme="light"]{
  --bg:#F5F4FB;
  --surf:#FFFFFF;
  --surf2:#EDECF7;
  --surf3:#E3E1F1;
  --text:#141420;
  --text2:#54526B;
  --text3:#75738C;
  --line:#DBD9EA;
  --line2:#C7C4DB;
  --pri:#3B2ADF;
  --on-pri:#FFFFFF;
  --pri-cont:#E2DEFF;
  --on-pri-cont:#180B84;
  --acc:#8A5A00;
  --acc-cont:#FFE7B3;
  --on-acc-cont:#3F2C00;
  --grid-ink:rgba(59,42,223,.055);
}

/* ==========================  base  ========================== */
*,*::before,*::after{box-sizing:border-box}
html{scroll-behavior:smooth;-webkit-text-size-adjust:100%}
body{
  margin:0;
  background:var(--bg);
  color:var(--text);
  font-family:var(--f-body);
  font-size:clamp(15.5px,.42vw + 14.6px,17px);
  line-height:1.65;
  letter-spacing:-.005em;
  overflow-x:hidden;
  transition:background .35s var(--ease), color .35s var(--ease);
}
img{max-width:100%;display:block}
a{color:inherit}
h1,h2,h3{font-family:var(--f-display);font-weight:800;line-height:1.02;letter-spacing:-.035em;margin:0}
p{margin:0 0 1em}
ul,ol{margin:0;padding:0;list-style:none}
.sprite{position:absolute;width:0;height:0;overflow:hidden}
svg{fill:none;stroke:currentColor;stroke-width:1.7;stroke-linecap:round;stroke-linejoin:round}

.wrap{width:100%;max-width:var(--w);margin-inline:auto;padding-inline:var(--pad)}

.skip{position:absolute;left:-9999px;top:0;z-index:200;background:var(--pri);color:var(--on-pri);
  padding:12px 20px;border-radius:0 0 var(--r-s) 0;font-weight:600}
.skip:focus{left:0}

:focus-visible{outline:3px solid var(--pri);outline-offset:3px;border-radius:6px}

/* ==========================  app bar  ========================== */
.bar{position:sticky;top:0;z-index:100;transition:background .3s var(--ease),border-color .3s var(--ease);
  border-bottom:1px solid transparent}
.bar.stuck{background:color-mix(in srgb,var(--bg) 82%,transparent);backdrop-filter:blur(18px) saturate(1.5);
  -webkit-backdrop-filter:blur(18px) saturate(1.5);border-bottom-color:var(--line)}
.bar-in{display:flex;align-items:center;gap:20px;height:74px}

.mark{display:flex;align-items:center;gap:12px;text-decoration:none;flex:0 0 auto}
.mark-tile{display:grid;place-items:center;width:42px;height:42px;border-radius:14px;
  background:var(--pri);color:var(--on-pri);font-family:var(--f-mono);font-weight:700;font-size:14px;
  letter-spacing:.02em}
.mark-txt{display:flex;flex-direction:column;line-height:1.15}
.mark-txt b{font-family:var(--f-display);font-weight:700;font-size:16px;letter-spacing:-.02em}
.mark-txt i{font-style:normal;font-family:var(--f-mono);font-size:10.5px;color:var(--text3);
  letter-spacing:.06em;text-transform:uppercase}

.nav{margin-left:auto;display:flex;gap:4px}
.nav a{position:relative;text-decoration:none;font-size:14.5px;font-weight:500;color:var(--text2);
  padding:9px 14px;border-radius:99px;transition:color .2s,background .2s}
.nav a:hover{color:var(--text);background:var(--surf2)}
.nav a.on{color:var(--on-pri-cont);background:var(--pri-cont)}

.bar-act{display:flex;gap:8px;align-items:center}
.icon-btn{width:42px;height:42px;display:grid;place-items:center;border-radius:14px;cursor:pointer;
  background:var(--surf2);border:1px solid var(--line);color:var(--text);transition:background .2s,border-color .2s}
.icon-btn:hover{background:var(--surf3);border-color:var(--line2)}
.icon-btn svg{width:19px;height:19px}
[data-theme="dark"] .ico-sun,[data-theme="light"] .ico-moon{display:none}
.menu{display:none;flex-direction:column;align-items:center;justify-content:center;gap:5px}
.menu span{display:block;width:17px;height:2px;background:currentColor;border-radius:2px;transition:transform .25s var(--ease)}
.menu[aria-expanded="true"] span:first-child{transform:translateY(3.5px) rotate(45deg)}
.menu[aria-expanded="true"] span:last-child{transform:translateY(-3.5px) rotate(-45deg)}

/* ==========================  hero  ========================== */
.hero{position:relative;padding:clamp(52px,9vw,104px) 0 clamp(64px,10vw,116px);overflow:hidden}
/* 8dp baseline grid — the layout unit Android is measured in */
.grid8{position:absolute;inset:-10% -10% auto -10%;height:120%;pointer-events:none;
  background-image:linear-gradient(var(--grid-ink) 1px,transparent 1px),
                   linear-gradient(90deg,var(--grid-ink) 1px,transparent 1px);
  background-size:72px 72px;
  -webkit-mask-image:radial-gradient(78% 62% at 14% 4%,#000 0%,transparent 68%);
  mask-image:radial-gradient(78% 62% at 14% 4%,#000 0%,transparent 68%)}
.hero-in{position:relative;z-index:1}

.eyebrow{font-family:var(--f-mono);font-size:11.5px;letter-spacing:.13em;text-transform:uppercase;
  color:var(--text3);margin:0 0 22px}
.hero h1{font-size:clamp(2.5rem,6.8vw,5rem);max-width:20ch}
.hero h1 em{font-style:normal;color:var(--pri);
  text-decoration:underline;text-decoration-thickness:.07em;text-underline-offset:.14em;
  text-decoration-color:color-mix(in srgb,var(--pri) 38%,transparent)}
.lede{max-width:56ch;color:var(--text2);font-size:clamp(1rem,.5vw + .92rem,1.14rem);margin:24px 0 0}

/* signature: the install meter */
.meter{margin-top:clamp(38px,5vw,56px);padding:clamp(24px,3.4vw,36px);border-radius:var(--r-l);
  background:var(--surf);border:1px solid var(--line);box-shadow:var(--e1);max-width:820px}
.meter-num{font-family:var(--f-display);font-weight:800;letter-spacing:-.05em;line-height:.92;
  font-size:clamp(2.9rem,10vw,6.2rem);color:var(--text);font-variant-numeric:tabular-nums}
.odo{display:inline-block}
.meter-cap{font-size:14.5px;color:var(--text2);margin:14px 0 0}
.meter-sub{display:flex;flex-wrap:wrap;gap:12px;margin-top:24px;padding-top:22px;border-top:1px solid var(--line)}
.meter-sub li{display:flex;align-items:baseline;gap:8px;padding:8px 16px;border-radius:99px;background:var(--surf2)}
.meter-sub b{font-family:var(--f-mono);font-size:17px;font-weight:700;color:var(--pri)}
.meter-sub span{font-size:13px;color:var(--text2)}

.cta{display:flex;flex-wrap:wrap;gap:12px;margin-top:34px}
.btn{display:inline-flex;align-items:center;gap:9px;text-decoration:none;font-weight:600;font-size:15px;
  padding:15px 27px;border-radius:99px;transition:transform .18s var(--ease),background .2s,box-shadow .2s;
  font-family:inherit;background:none;border:none;cursor:pointer;-webkit-appearance:none;appearance:none}
.btn:active{transform:scale(.97)}
.btn-fill{background:var(--pri);color:var(--on-pri);box-shadow:var(--e1)}
.btn-fill:hover{box-shadow:var(--e2)}
.btn-line{border:1px solid var(--line2);color:var(--text)}
.btn-line:hover{background:var(--surf2)}
.tick{width:17px;height:17px;transition:transform .22s var(--ease)}
.btn-line:hover .tick{transform:translateX(4px)}

.stack{display:flex;flex-wrap:wrap;gap:8px;margin-top:32px}
.stack li{font-family:var(--f-mono);font-size:11.5px;letter-spacing:.04em;color:var(--text2);
  padding:7px 13px;border:1px dashed var(--line2);border-radius:99px}

/* ==========================  sections  ========================== */
.sec{padding-block:var(--gap-sec)}
.tag{font-family:var(--f-mono);font-size:11.5px;letter-spacing:.13em;text-transform:uppercase;
  color:var(--pri);margin:0 0 14px}
.tag.small{margin-bottom:18px;color:var(--text3)}
.sec h2{font-size:clamp(1.85rem,4.2vw,3.1rem)}
.head{margin-bottom:clamp(36px,5vw,56px);max-width:34ch}
.head-row{display:flex;align-items:flex-end;justify-content:space-between;gap:24px;max-width:none;flex-wrap:wrap}
.head-note{font-family:var(--f-mono);font-size:12.5px;color:var(--text3);margin:0}
.head-link{display:inline-flex;align-items:center;gap:8px;text-decoration:none;font-size:14.5px;font-weight:600;color:var(--pri)}
.head-link svg{width:16px;height:16px;transition:transform .22s var(--ease)}
.head-link:hover svg{transform:translateX(4px)}

/* about */
.two{display:grid;grid-template-columns:minmax(0,.85fr) minmax(0,1.4fr);gap:clamp(28px,5vw,72px);align-items:start}
.two-side{position:sticky;top:104px}
.two-main p{color:var(--text2)}
.big{font-family:var(--f-display);font-weight:600;font-size:clamp(1.2rem,1.5vw + .9rem,1.6rem);
  line-height:1.35;letter-spacing:-.025em;color:var(--text)!important;margin-bottom:1.1em}
.facts{display:grid;grid-template-columns:repeat(auto-fit,minmax(220px,1fr));gap:1px;margin:36px 0 0;
  background:var(--line);border:1px solid var(--line);border-radius:var(--r-m);overflow:hidden}
.facts>div{background:var(--surf);padding:18px 20px}
.facts dt{font-family:var(--f-mono);font-size:10.5px;letter-spacing:.1em;text-transform:uppercase;color:var(--text3)}
.facts dd{margin:6px 0 0;font-size:14.5px;font-weight:500}

/* skill cards */
.cards{display:grid;grid-template-columns:repeat(auto-fit,minmax(288px,1fr));gap:16px}
.card{background:var(--surf);border:1px solid var(--line);border-radius:var(--r-l);padding:28px;
  transition:transform .28s var(--ease),border-color .28s,box-shadow .28s}
.card:hover{transform:translateY(-4px);border-color:var(--line2);box-shadow:var(--e2)}
.ci{display:grid;place-items:center;width:50px;height:50px;border-radius:16px;
  background:var(--pri-cont);color:var(--on-pri-cont);margin-bottom:20px}
.ci svg{width:23px;height:23px}
.card h3{font-size:1.14rem;letter-spacing:-.025em;margin-bottom:9px}
.card p{margin:0;color:var(--text2);font-size:14.6px;line-height:1.6}

.chips-block{margin-top:clamp(44px,6vw,68px);padding-top:clamp(36px,5vw,52px);border-top:1px solid var(--line)}
.chips{display:flex;flex-wrap:wrap;gap:8px}
.chips li{font-family:var(--f-mono);font-size:12px;padding:8px 14px;border-radius:var(--r-xs);
  background:var(--surf2);color:var(--text2);border:1px solid transparent;transition:border-color .2s,color .2s}
.chips li:hover{color:var(--text);border-color:var(--line2)}

/* timeline */
.tl{display:grid;gap:0}
.tl-item{display:grid;grid-template-columns:220px minmax(0,1fr);gap:clamp(20px,4vw,48px);
  padding-block:clamp(30px,4vw,42px);border-top:1px solid var(--line)}
.tl-item:last-child{border-bottom:1px solid var(--line)}
.tl-when{display:flex;align-items:center;align-self:start;gap:11px;padding-top:9px}
.tl-when time{font-family:var(--f-mono);font-size:12.5px;color:var(--text2);letter-spacing:-.01em}
.dot{width:9px;height:9px;border-radius:50%;background:var(--pri);flex:0 0 auto;
  box-shadow:0 0 0 4px color-mix(in srgb,var(--pri) 18%,transparent)}
.tl-body h3{font-size:1.35rem;letter-spacing:-.03em}
.tl-org{font-family:var(--f-mono);font-size:13px;color:var(--pri);margin:7px 0 16px}
.tl-body ul{display:grid;gap:9px}
.tl-body li{position:relative;padding-left:20px;color:var(--text2);font-size:14.8px;line-height:1.6}
.tl-body li::before{content:"";position:absolute;left:0;top:.68em;width:7px;height:1.5px;background:var(--line2)}

/* apps */
.filters{display:flex;flex-wrap:wrap;gap:8px;margin-bottom:28px}
.chip-btn{font-family:var(--f-body);font-size:13.5px;font-weight:500;padding:9px 17px;border-radius:99px;
  cursor:pointer;background:transparent;border:1px solid var(--line2);color:var(--text2);
  transition:background .2s,color .2s,border-color .2s}
.chip-btn:hover{background:var(--surf2);color:var(--text)}
.chip-btn.is-on{background:var(--pri-cont);border-color:transparent;color:var(--on-pri-cont);font-weight:600}

.apps{display:grid;grid-template-columns:repeat(auto-fill,minmax(300px,1fr));gap:16px}
.app{display:flex;flex-direction:column;background:var(--surf);border:1px solid var(--line);
  border-radius:var(--r-l);padding:24px;transition:transform .28s var(--ease),border-color .28s,box-shadow .28s}
.app:hover{transform:translateY(-4px);border-color:var(--line2);box-shadow:var(--e2)}
.app[hidden]{display:none}
.app-ic{position:relative;display:grid;place-items:center;width:58px;height:58px;border-radius:18px;
  overflow:hidden;margin-bottom:18px;
  background:hsl(var(--h) 62% 90%);color:hsl(var(--h) 58% 32%)}
[data-theme="dark"] .app-ic{background:hsl(var(--h) 40% 18%);color:hsl(var(--h) 82% 76%)}
.app-ic img{position:absolute;inset:0;width:100%;height:100%;object-fit:cover;border-radius:inherit}
.app-ic svg{width:26px;height:26px}
.app-txt{flex:1}
.app h3{font-size:1.06rem;letter-spacing:-.025em;margin-bottom:8px}
.app-txt p{margin:0;color:var(--text2);font-size:14.2px;line-height:1.58}
.app-foot{display:flex;align-items:center;justify-content:space-between;gap:12px;flex-wrap:wrap;
  margin-top:22px;padding-top:18px;border-top:1px solid var(--line)}
.pill{font-family:var(--f-mono);font-size:11.5px;font-weight:500;padding:6px 12px;border-radius:99px;
  background:var(--acc-cont);color:var(--on-acc-cont);white-space:nowrap}
.app-link{display:inline-flex;align-items:center;gap:7px;text-decoration:none;font-size:13.5px;
  font-weight:600;color:var(--pri)}
.app-link svg{width:15px;height:15px;transition:transform .22s var(--ease)}
.app-link:hover svg{transform:translateX(4px)}
.empty{margin-top:28px;color:var(--text3);font-family:var(--f-mono);font-size:13px}
.apps-more{display:flex;justify-content:center;margin-top:28px}
.apps-more .btn[hidden]{display:none}

/* writing */
.posts{display:grid;grid-template-columns:repeat(auto-fit,minmax(292px,1fr));gap:16px}
.post{display:flex;flex-direction:column;text-decoration:none;background:var(--surf);
  border:1px solid var(--line);border-radius:var(--r-l);padding:28px;
  transition:transform .28s var(--ease),border-color .28s,box-shadow .28s}
.post:hover{transform:translateY(-4px);border-color:var(--line2);box-shadow:var(--e2)}
.post-meta{font-family:var(--f-mono);font-size:11px;letter-spacing:.08em;text-transform:uppercase;
  color:var(--text3);margin:0 0 16px}
.post h3{font-size:1.1rem;letter-spacing:-.025em;margin-bottom:10px}
.post-sum{flex:1;margin:0;color:var(--text2);font-size:14.2px;line-height:1.58}
.post-go{display:inline-flex;align-items:center;gap:7px;margin-top:22px;font-size:13.5px;
  font-weight:600;color:var(--pri)}
.post-go svg{width:15px;height:15px;transition:transform .22s var(--ease)}
.post:hover .post-go svg{transform:translateX(4px)}

/* contact */
.sec-contact{padding-bottom:clamp(56px,7vw,88px)}
.contact-card{background:var(--surf);border:1px solid var(--line);border-radius:var(--r-xl);
  padding:clamp(32px,5.5vw,72px);text-align:center}
.contact-card .tag{color:var(--pri)}
.contact-card .lede{margin:20px auto 0;max-width:50ch}
.mailto{display:inline-flex;align-items:center;gap:13px;margin-top:34px;text-decoration:none;
  background:var(--pri);color:var(--on-pri);padding:17px 30px;border-radius:99px;font-weight:600;
  font-size:clamp(15px,1.6vw,17.5px);box-shadow:var(--e1);
  transition:transform .18s var(--ease),box-shadow .2s;word-break:break-word}
.mailto:hover{box-shadow:var(--e2)}
.mailto:active{transform:scale(.97)}
.mailto svg{width:21px;height:21px;flex:0 0 auto}
.social{display:flex;flex-wrap:wrap;justify-content:center;gap:8px;margin-top:32px}
.social a{display:block;text-decoration:none;font-size:13.5px;font-weight:500;color:var(--text2);
  padding:9px 17px;border-radius:99px;border:1px solid var(--line);transition:color .2s,border-color .2s,background .2s}
.social a:hover{color:var(--text);background:var(--surf2);border-color:var(--line2)}

/* footer */
.foot{border-top:1px solid var(--line)}
.foot-in{display:flex;align-items:center;justify-content:space-between;gap:16px;flex-wrap:wrap;
  padding-block:30px;font-size:13.5px;color:var(--text3)}
.foot p{margin:0}
.foot a{text-decoration:none;font-weight:500}
.foot a:hover{color:var(--text)}

/* ==========================  motion  ========================== */
.reveal,.js .card,.js .app,.js .post,.js .tl-item,.js .facts{opacity:0;transform:translateY(22px)}
.js .in,.reveal.in{opacity:1;transform:none;transition:opacity .6s var(--ease),transform .6s var(--ease)}
html:not(.js) .reveal{opacity:1;transform:none}

/* ==========================  responsive  ========================== */
@media (max-width:900px){
  .two{grid-template-columns:1fr}
  .two-side{position:static}
  .tl-item{grid-template-columns:1fr;gap:14px}
  .tl-when{padding-top:0}
}
@media (max-width:760px){
  .menu{display:flex}
  .bar-act{margin-left:auto}
  .nav{position:fixed;inset:74px 0 auto;flex-direction:column;gap:2px;padding:14px var(--pad) 26px;
    background:var(--bg);border-bottom:1px solid var(--line);
    transform:translateY(-130%);transition:transform .34s var(--ease);margin:0}
  .nav.open{transform:none}
  .nav a{padding:14px 16px;font-size:16px;border-radius:var(--r-s)}
  .mark-txt i{display:none}
  .meter-sub li{flex:1 1 100%}
  .cta .btn{flex:1 1 100%;justify-content:center}
  .foot-in{justify-content:center;text-align:center}
  .social{justify-content:flex-start}
  .mailto{font-size:13px;padding:14px 18px;gap:9px;white-space:nowrap}
}
@media (max-width:420px){
  .mark-txt b{font-size:15px}
  .apps,.cards,.posts{grid-template-columns:1fr}
}

@media (prefers-reduced-motion:reduce){
  html{scroll-behavior:auto}
  *,*::before,*::after{animation-duration:.001ms!important;transition-duration:.001ms!important}
  .reveal,.js .card,.js .app,.js .post,.js .tl-item,.js .facts{opacity:1;transform:none}
}

@media print{
  .bar,.filters,.grid8,.foot a,.cta{display:none}
  body{background:#fff;color:#000}
  .card,.app,.post,.meter,.contact-card{border:1px solid #ccc;box-shadow:none;break-inside:avoid}
}