/* ============================================================
   Bandaru Badri Nadh Sai — Personal Portfolio (FINAL)
   Editorial ink + brass. Serif display, restrained motion,
   fail-open reveals. Related to BNS in polish, not in design.
   ============================================================ */
*,*::before,*::after{box-sizing:border-box;margin:0;padding:0}
html{scroll-behavior:smooth;scroll-padding-top:84px;overflow-x:hidden;-webkit-text-size-adjust:100%}
body{font-family:"Inter",system-ui,-apple-system,"Segoe UI",sans-serif;background:var(--bg);color:var(--text);line-height:1.7;font-size:16px;-webkit-font-smoothing:antialiased;overflow-x:hidden;transition:background-color .35s ease,color .35s ease}
img,svg{max-width:100%;display:block}
a{color:inherit}
ul,ol{list-style:none}
button{font-family:inherit;cursor:pointer;background:none;border:none;color:inherit}
::selection{background:var(--accent);color:var(--accent-ink)}
:focus-visible{outline:2px solid var(--accent);outline-offset:3px;border-radius:2px}

/* ---------- TOKENS ---------- */
:root{
  --font-d:"Fraunces",Georgia,serif;
  --font-b:"Inter",system-ui,sans-serif;
  --font-m:ui-monospace,"SF Mono","Cascadia Code",Menlo,Consolas,monospace;
  --maxw:1140px;
  --nav:72px;
  --ease:cubic-bezier(.22,1,.36,1);
}
:root,[data-theme="dark"]{
  color-scheme:dark;
  --bg:#141318;
  --bg2:#1C1B22;
  --bg3:#232230;
  --text:#F2EFE6;
  --text2:#D8D3C8;
  --muted:#A39D92;
  --faint:#6E695F;
  --line:rgba(242,239,230,.12);
  --line2:rgba(242,239,230,.24);
  --accent:#C99B4A;
  --accent-ink:#141318;
  --teal:#3E9B8F;
  --card:#191820;
  --input:#101016;
  --navbg:rgba(20,19,24,.85);
  --shadow:0 24px 60px -28px rgba(0,0,0,.7);
}
[data-theme="light"]{
  color-scheme:light;
  --bg:#F5F1E8;
  --bg2:#FFFFFF;
  --bg3:#EFE9DB;
  --text:#191822;
  --text2:#2C2B36;
  --muted:#5F5B54;
  --faint:#98918A;
  --line:rgba(25,24,34,.13);
  --line2:rgba(25,24,34,.26);
  --accent:#96702A;
  --accent-ink:#FFFFFF;
  --teal:#1F7A6E;
  --card:#FFFFFF;
  --input:#FFFFFF;
  --navbg:rgba(245,241,232,.88);
  --shadow:0 24px 60px -30px rgba(25,24,34,.35);
}

/* ---------- LAYOUT / TYPE ---------- */
.container{width:100%;max-width:var(--maxw);margin:0 auto;padding:0 32px}
.section{padding:104px 0;position:relative}
.display{font-family:var(--font-d);font-weight:600;letter-spacing:-.01em;text-wrap:balance}
.eyebrow{display:inline-flex;align-items:center;gap:10px;font-family:var(--font-m);font-size:11px;letter-spacing:.24em;text-transform:uppercase;color:var(--muted)}
.eyebrow i{width:7px;height:7px;background:var(--accent);border-radius:50%;flex-shrink:0}
.shead{display:flex;gap:22px;align-items:flex-start;margin-bottom:52px}
.shead__no{font-family:var(--font-d);font-size:.95rem;color:var(--accent);border:1px solid var(--line2);border-radius:50%;width:46px;height:46px;display:flex;align-items:center;justify-content:center;flex-shrink:0}
.shead__label{font-family:var(--font-m);font-size:11px;letter-spacing:.24em;text-transform:uppercase;color:var(--faint);margin-bottom:8px}
.shead__title{font-size:clamp(1.9rem,4vw,3rem);line-height:1.05}

/* fail-open reveals: visible unless html.js + not yet observed */
.reveal{transition:opacity .8s var(--ease),transform .8s var(--ease);transition-delay:var(--d,0s)}
html.js .reveal{opacity:0;transform:translateY(26px)}
html.js .reveal.in{opacity:1;transform:none}

/* ---------- NAV ---------- */
.nav-wrap{position:fixed;top:0;left:0;right:0;z-index:200;transition:background .3s,border-color .3s}
.nav-wrap.scrolled{background:var(--navbg);backdrop-filter:blur(12px);-webkit-backdrop-filter:blur(12px);border-bottom:1px solid var(--line)}
.nav{max-width:var(--maxw);margin:0 auto;padding:0 32px;height:var(--nav);display:flex;align-items:center;justify-content:space-between;gap:20px}
.nav__brand{display:flex;align-items:center;gap:11px;font-family:var(--font-d);font-weight:600;font-size:1.02rem;text-decoration:none}
.nav__logo{width:34px;height:34px;border-radius:9px;background:var(--accent);color:var(--accent-ink);display:flex;align-items:center;justify-content:center;font-weight:700;font-size:1.05rem;flex-shrink:0}
.nav__menu{display:flex;align-items:center;gap:26px}
.nav__menu a{text-decoration:none;font-size:.86rem;color:var(--muted);transition:color .2s}
.nav__menu a:hover{color:var(--text)}
.nav__cta{border:1px solid var(--line2);border-radius:99px;padding:8px 18px!important;color:var(--text)!important;transition:border-color .25s,background .25s!important}
.nav__cta:hover{border-color:var(--accent);background:rgba(201,155,74,.12)}
.theme-toggle{width:36px;height:36px;border:1px solid var(--line2);border-radius:50%;display:inline-flex;align-items:center;justify-content:center;color:var(--muted);font-size:1rem;transition:border-color .25s,color .25s}
.theme-toggle:hover{border-color:var(--accent);color:var(--accent)}
.theme-toggle .sun{display:none}
[data-theme="light"] .theme-toggle .sun{display:inline}
[data-theme="light"] .theme-toggle .moon{display:none}
.nav__toggle{display:none;flex-direction:column;gap:6px;padding:10px}
.nav__toggle span{display:block;width:24px;height:2px;background:var(--text);transition:transform .3s,opacity .3s}
.nav__toggle.x span:nth-child(1){transform:translateY(8px) rotate(45deg)}
.nav__toggle.x span:nth-child(2){opacity:0}
.nav__toggle.x span:nth-child(3){transform:translateY(-8px) rotate(-45deg)}
.skip{position:absolute;left:-999px;top:0;background:var(--accent);color:var(--accent-ink);padding:10px 16px;z-index:999;font-weight:600}
.skip:focus{left:8px;top:8px}

/* ---------- HERO ---------- */
.hero{position:relative;overflow:hidden;padding:calc(var(--nav) + 64px) 0 0}
.hero__inner{display:grid;grid-template-columns:1.15fr .85fr;gap:64px;align-items:center;position:relative;z-index:2}
.hero__name{font-size:clamp(3rem,7.6vw,5.9rem);line-height:1.0;margin:20px 0 6px}
.hero__name .line{display:block;overflow:hidden}
.hero__name .line > span{display:block}
html.js .hero__name .line > span{transform:translateY(104%);transition:transform 1s var(--ease)}
html.js .hero__name.in .line > span{transform:none}
.hero__name .line--accent{font-style:italic;color:var(--accent)}
.hero__role{font-family:var(--font-d);font-size:clamp(1.05rem,2vw,1.35rem);color:var(--text2);margin-top:14px}
.hero__role b{font-weight:600}
.hero__lede{color:var(--muted);max-width:46ch;margin-top:16px}
.hero__lede em{font-style:normal;color:var(--text);border-bottom:1px solid var(--accent)}
.hero__founder{margin-top:18px;font-size:.92rem;color:var(--muted)}
.hero__founder a{color:var(--text);font-weight:600;text-underline-offset:4px}
.hero__actions{display:flex;gap:12px;flex-wrap:wrap;margin-top:30px}
.hero__social{display:flex;gap:22px;margin-top:22px;font-family:var(--font-m);font-size:.8rem;letter-spacing:.08em}
.hero__social a{color:var(--muted);text-decoration:none;border-bottom:1px solid var(--line2);padding-bottom:2px;transition:color .2s,border-color .2s}
.hero__social a:hover{color:var(--accent);border-color:var(--accent)}
.btn{display:inline-flex;align-items:center;gap:10px;padding:15px 28px;border-radius:99px;font-weight:600;font-size:.88rem;text-decoration:none;transition:transform .25s,background .25s,color .25s,border-color .25s;white-space:nowrap}
.btn:active{transform:scale(.98)}
.btn--primary{background:var(--accent);color:var(--accent-ink)}
.btn--primary:hover{transform:translateY(-2px)}
.btn--ghost{border:1px solid var(--line2);color:var(--text)}
.btn--ghost:hover{border-color:var(--accent);transform:translateY(-2px)}
.btn--sm{padding:10px 20px;font-size:.78rem}
.btn--text{padding:15px 6px;color:var(--muted)}
.btn--text:hover{color:var(--accent)}

/* portrait: fixed 4/5 frame, face-anchored crop, swap-safe */
.portrait{position:relative}
.portrait__frame{aspect-ratio:4/5;border-radius:14px;overflow:hidden;border:1px solid var(--line2);box-shadow:var(--shadow);background:var(--bg2);max-width:380px;margin-left:auto}
.portrait__frame img{width:100%;height:100%;object-fit:cover;object-position:50% 18%}
.portrait__badge{position:absolute;left:-14px;bottom:34px;background:var(--card);border:1px solid var(--line2);border-radius:10px;padding:12px 16px;box-shadow:var(--shadow);font-family:var(--font-m);font-size:.7rem;letter-spacing:.14em;text-transform:uppercase;color:var(--muted)}
.portrait__badge b{display:block;color:var(--accent);font-size:.8rem;margin-top:2px}
.portrait__caption{font-family:var(--font-m);font-size:.72rem;letter-spacing:.18em;text-transform:uppercase;color:var(--faint);margin-top:14px;text-align:right}

/* signature visual: knowledge chain */
.sig{position:relative;z-index:1;margin-top:56px;border-top:1px solid var(--line);border-bottom:1px solid var(--line);background:var(--bg2)}
.sig svg{width:100%;height:auto;display:block}
.sig__cap{display:flex;justify-content:space-between;gap:12px;padding:12px 0 16px;font-family:var(--font-m);font-size:.68rem;letter-spacing:.2em;color:var(--faint);text-transform:uppercase;flex-wrap:wrap}
.flowline{stroke-dasharray:7 7;animation:flowmove 1.8s linear infinite}
@keyframes flowmove{to{stroke-dashoffset:-28}}
.pulse{animation:pulse 2.6s ease-in-out infinite}
@keyframes pulse{0%,100%{opacity:1}50%{opacity:.3}}

/* ---------- ABOUT ---------- */
.about{display:grid;grid-template-columns:1fr 1fr;gap:56px;align-items:start}
.about__lead{font-family:var(--font-d);font-size:clamp(1.4rem,2.6vw,2rem);line-height:1.3}
.about__lead b{color:var(--accent);font-weight:600}
.about__body p{color:var(--muted);margin-bottom:16px;max-width:56ch}
.about__body p strong{color:var(--text);font-weight:600}
.about__body a{color:var(--text);font-weight:600;text-underline-offset:4px}
.facts{margin-top:8px;border-top:1px solid var(--line)}
.facts div{display:flex;justify-content:space-between;gap:18px;padding:15px 0;border-bottom:1px solid var(--line);font-size:.9rem}
.facts dt{font-family:var(--font-m);font-size:.68rem;letter-spacing:.2em;text-transform:uppercase;color:var(--faint);padding-top:4px}
.facts dd{color:var(--text2);text-align:right}

/* ---------- SKILLS ---------- */
.skills{display:grid;grid-template-columns:.9fr 1.1fr;gap:56px;align-items:start}
.skills__big{font-family:var(--font-d);font-size:clamp(1.7rem,3.4vw,2.6rem);line-height:1.25;font-weight:500}
.skills__big li{border-bottom:1px solid var(--line);padding:10px 0}
.skills__big li::after{content:'·';color:var(--accent);margin-left:12px}
.skgroups{display:grid;gap:0;border-top:1px solid var(--line)}
.skgrp{display:grid;grid-template-columns:180px 1fr;gap:18px;padding:16px 0;border-bottom:1px solid var(--line);font-size:.9rem}
.skgrp h3{font-family:var(--font-m);font-size:.7rem;letter-spacing:.2em;text-transform:uppercase;color:var(--faint);padding-top:4px;font-weight:500}
.skgrp p{color:var(--text2)}

/* ---------- PROJECTS ---------- */
.proj-filters{display:flex;gap:10px;flex-wrap:wrap;margin-bottom:36px}
.filter{font-family:var(--font-m);font-size:.72rem;letter-spacing:.14em;text-transform:uppercase;border:1px solid var(--line2);border-radius:99px;padding:9px 18px;color:var(--muted);transition:all .25s}
.filter:hover{border-color:var(--accent);color:var(--text)}
.filter.is-active{background:var(--accent);border-color:var(--accent);color:var(--accent-ink)}
.projects{display:grid;grid-template-columns:1fr 1fr;gap:28px}
.project{border:1px solid var(--line2);border-radius:14px;background:var(--card);overflow:hidden;transition:border-color .3s,transform .3s;display:flex;flex-direction:column}
.project:hover{border-color:var(--accent)}
.project.is-hidden{display:none}
.project__vis{border-bottom:1px solid var(--line);background:var(--bg2)}
.project__vis svg{width:100%;height:auto}
.project__body{padding:30px 28px;display:flex;flex-direction:column;gap:12px;flex:1}
.project__meta{display:flex;justify-content:space-between;align-items:center;font-family:var(--font-m);font-size:.68rem;letter-spacing:.18em;text-transform:uppercase;color:var(--faint)}
.project__kind{color:var(--accent)}
.project h3{font-family:var(--font-d);font-size:1.45rem;line-height:1.15;font-weight:600}
.project__lede{color:var(--muted);font-size:.92rem}
.project__more{overflow:hidden;max-height:0;transition:max-height .5s var(--ease)}
.project.open .project__more{max-height:420px}
.project__more p{font-size:.88rem;color:var(--muted);margin:10px 0}
.project__more p span{font-family:var(--font-m);font-size:.66rem;letter-spacing:.16em;text-transform:uppercase;color:var(--accent);display:block;margin-bottom:2px}
.project__tech{display:flex;gap:8px;flex-wrap:wrap;margin-top:4px}
.project__tech li{font-family:var(--font-m);font-size:.68rem;letter-spacing:.08em;border:1px solid var(--line2);border-radius:99px;padding:5px 12px;color:var(--muted)}
.project__foot{display:flex;gap:10px;align-items:center;margin-top:auto;padding-top:16px;flex-wrap:wrap}
.expand{margin-left:auto;font-family:var(--font-m);font-size:.72rem;letter-spacing:.12em;text-transform:uppercase;color:var(--muted);border-bottom:1px solid var(--line2);padding-bottom:2px}
.expand:hover{color:var(--accent);border-color:var(--accent)}

/* ---------- TIMELINE (education / training) ---------- */
.tline{border-top:1px solid var(--line)}
.trow{display:grid;grid-template-columns:130px 1fr auto;gap:26px;align-items:start;padding:28px 0;border-bottom:1px solid var(--line)}
.trow__year{font-family:var(--font-m);font-size:.78rem;color:var(--accent);padding-top:5px;white-space:nowrap}
.trow h3{font-family:var(--font-d);font-size:1.3rem;font-weight:600}
.trow__sub{color:var(--muted);font-size:.92rem;margin-top:4px;max-width:60ch}
.trow__meta{font-family:var(--font-m);font-size:.7rem;letter-spacing:.14em;text-transform:uppercase;color:var(--faint);padding-top:6px;text-align:right}
.tag{display:inline-block;font-family:var(--font-m);font-size:.64rem;letter-spacing:.16em;text-transform:uppercase;border:1px solid var(--line2);border-radius:99px;padding:4px 12px;color:var(--muted);margin-top:10px;margin-right:8px}

/* ---------- CERTS ---------- */
.certs{display:grid;grid-template-columns:1fr 1fr;gap:20px}
.cert{border:1px solid var(--line2);border-radius:12px;padding:26px;background:var(--card);display:flex;gap:18px;transition:border-color .3s}
.cert:hover{border-color:var(--accent)}
.cert__no{font-family:var(--font-d);color:var(--accent);font-size:1rem;flex-shrink:0}
.cert__org{font-family:var(--font-m);font-size:.68rem;letter-spacing:.2em;text-transform:uppercase;color:var(--faint);margin-bottom:6px}
.cert h3{font-size:1.02rem;font-weight:600;line-height:1.4}

/* ---------- BNS IDENTITY ---------- */
.bnsband{border-top:1px solid var(--line);border-bottom:1px solid var(--line);background:var(--bg2)}
.bns{display:grid;grid-template-columns:1fr auto;gap:40px;align-items:center;padding:72px 0}
.bns h2{font-family:var(--font-d);font-size:clamp(1.7rem,3.4vw,2.6rem);line-height:1.1;margin:14px 0 12px}
.bns h2 em{font-style:italic;color:var(--accent)}
.bns p{color:var(--muted);max-width:58ch}
.bns__mark{width:120px;height:120px;border:1px solid var(--line2);border-radius:24px;background:var(--card);display:flex;flex-direction:column;align-items:center;justify-content:center;gap:4px;flex-shrink:0}
.bns__mark b{font-family:var(--font-d);font-size:1.6rem;letter-spacing:.08em}
.bns__mark span{font-family:var(--font-m);font-size:.6rem;letter-spacing:.24em;color:var(--faint)}
.bns__row{display:flex;gap:12px;flex-wrap:wrap;margin-top:26px}

/* ---------- CONTACT ---------- */
.contact{display:grid;grid-template-columns:1fr 1fr;gap:64px;align-items:start}
.contact__cta{font-family:var(--font-d);font-size:clamp(2rem,4.6vw,3.4rem);line-height:1.05;margin-bottom:26px}
.contact__cta em{font-style:italic;color:var(--accent)}
.clinks{display:grid;border-top:1px solid var(--line);margin-top:8px}
.clinks li{display:flex;justify-content:space-between;gap:18px;align-items:center;padding:16px 0;border-bottom:1px solid var(--line);font-size:.92rem}
.clinks span{font-family:var(--font-m);font-size:.68rem;letter-spacing:.2em;text-transform:uppercase;color:var(--faint)}
.clinks a{color:var(--text);font-weight:500;word-break:break-all}
.clinks a:hover{color:var(--accent)}
.cform{background:var(--card);border:1px solid var(--line2);border-radius:14px;padding:34px 30px}
.field{margin-bottom:18px}
.field label{display:block;font-family:var(--font-m);font-size:.68rem;letter-spacing:.2em;text-transform:uppercase;color:var(--muted);margin-bottom:8px}
.field input,.field textarea{width:100%;padding:14px 16px;background:var(--input);border:1px solid var(--line2);border-radius:8px;color:var(--text);font-size:.94rem;font-family:inherit;outline:none;transition:border-color .25s,box-shadow .25s}
.field input:focus,.field textarea:focus{border-color:var(--accent);box-shadow:0 0 0 3px rgba(201,155,74,.18)}
.field textarea{min-height:130px;resize:vertical}
.cnote{font-size:.8rem;color:var(--faint);margin-top:14px;line-height:1.6}

/* ---------- FOOTER ---------- */
footer{border-top:1px solid var(--line);padding:64px 0 0;margin-top:40px}
.f-grid{display:grid;grid-template-columns:1.4fr 1fr 1fr;gap:44px;padding-bottom:48px}
.f-name{font-family:var(--font-d);font-size:1.4rem;font-weight:600}
.f-tag{color:var(--muted);font-size:.88rem;margin-top:6px;max-width:34ch}
.f-h{font-family:var(--font-m);font-size:.68rem;letter-spacing:.22em;text-transform:uppercase;color:var(--faint);margin-bottom:16px}
.f-links{display:grid;gap:10px;font-size:.88rem}
.f-links a{color:var(--muted);text-decoration:none}
.f-links a:hover{color:var(--accent)}
.f-bot{display:flex;justify-content:space-between;gap:12px;flex-wrap:wrap;padding:22px 0;border-top:1px solid var(--line);font-family:var(--font-m);font-size:.7rem;letter-spacing:.1em;color:var(--faint)}

/* ---------- 404 ---------- */
.missing{min-height:100svh;display:flex;align-items:center;padding-top:var(--nav)}
.missing h1{font-family:var(--font-d);font-size:clamp(3rem,9vw,6.5rem);line-height:1;letter-spacing:-.02em}
.missing h1 em{font-style:italic;color:var(--accent)}
.missing p{color:var(--muted);margin:18px 0 30px;max-width:44ch}

/* ---------- PROGRESS ---------- */
.progress{position:fixed;top:0;left:0;height:2px;width:0;z-index:300;background:var(--accent)}

/* ---------- RESPONSIVE ---------- */
@media(max-width:1024px){
  .hero__inner{grid-template-columns:1fr;gap:48px}
  .portrait__frame{margin:0 auto}
  .portrait__caption{text-align:center}
  .portrait__badge{left:8px}
  .about,.skills{grid-template-columns:1fr;gap:40px}
  .projects{grid-template-columns:1fr}
  .contact{grid-template-columns:1fr;gap:48px}
  .bns{grid-template-columns:1fr;gap:28px;padding:60px 0}
}
@media(max-width:920px){
  .nav__menu{position:fixed;inset:var(--nav) 0 auto 0;background:var(--bg);border-bottom:1px solid var(--line);flex-direction:column;align-items:stretch;padding:12px 22px 26px;gap:2px;transform:translateY(-130%);transition:transform .4s var(--ease),visibility 0s .4s;visibility:hidden}
  .nav__menu.open{transform:none;visibility:visible;transition:transform .4s var(--ease)}
  .nav__menu a{padding:13px 0;border-bottom:1px solid var(--line);font-size:1.02rem}
  .nav__menu .nav__cta{border:1px solid var(--line2);text-align:center;margin-top:12px;border-radius:99px}
  .nav__toggle{display:flex}
}
@media(max-width:760px){
  .container{padding:0 22px}
  .nav{padding:0 22px}
  .section{padding:80px 0}
  .hero{padding-top:calc(var(--nav) + 40px)}
  .hero__actions .btn{flex:1 1 auto;justify-content:center}
  .trow{grid-template-columns:1fr;gap:8px;padding:22px 0}
  .trow__meta{text-align:left}
  .certs{grid-template-columns:1fr}
  .skgrp{grid-template-columns:1fr;gap:6px}
  .f-grid{grid-template-columns:1fr;gap:28px}
  .cform{padding:26px 22px}
  .portrait__badge{position:static;margin-top:14px;display:inline-block}
}
@media(prefers-reduced-motion:reduce){
  *,*::before,*::after{animation-duration:.01ms!important;transition-duration:.01ms!important;scroll-behavior:auto!important}
  html.js .reveal{opacity:1;transform:none}
  html.js .hero__name .line > span{transform:none}
}