/* ============================================================
   Shardul Kulkarni — portfolio
   "Engineering ledger": dark carbon editorial, copper accent.
   Instrument Serif (display) · Archivo (body) · IBM Plex Mono (meta)
   ============================================================ */

:root {
  --bg: #0b0c0e;
  --bg-raise: #121316;
  --bg-raise-2: #17181c;
  --line: #26282c;
  --text: #e7e4dd;
  --text-dim: #9b988f;
  --accent: #d9974c;
  --accent-soft: rgba(217, 151, 76, 0.14);
  --serif: "Instrument Serif", Georgia, serif;
  --sans: "Archivo", "Helvetica Neue", sans-serif;
  --mono: "IBM Plex Mono", ui-monospace, monospace;
  --rail-w: 210px;
  --maxw: 880px;
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  background-color: var(--bg);
  background-image:
    radial-gradient(ellipse 80% 50% at 70% -10%, rgba(217, 151, 76, 0.07), transparent 60%),
    linear-gradient(rgba(231, 228, 221, 0.025) 1px, transparent 1px),
    linear-gradient(90deg, rgba(231, 228, 221, 0.025) 1px, transparent 1px);
  background-size: auto, 56px 56px, 56px 56px;
  color: var(--text);
  font-family: var(--sans);
  font-size: 16.5px;
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
}

::selection { background: var(--accent); color: var(--bg); }

/* film-grain overlay */
.grain {
  position: fixed; inset: 0; z-index: 2; pointer-events: none; opacity: 0.5;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='160' height='160'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.9' numOctaves='2'/%3E%3CfeColorMatrix values='0 0 0 0 0.9 0 0 0 0 0.89 0 0 0 0 0.87 0 0 0 0.035 0'/%3E%3C/filter%3E%3Crect width='160' height='160' filter='url(%23n)'/%3E%3C/svg%3E");
}

#progress-bar {
  position: fixed; top: 0; left: 0; height: 2px; width: 0;
  background: var(--accent); z-index: 100;
}

a { color: var(--accent); text-decoration: none; }
a:hover { text-decoration: underline; text-underline-offset: 3px; }

/* ---------------- left rail ---------------- */
.rail {
  position: fixed; top: 0; left: 0; bottom: 0; width: var(--rail-w);
  display: flex; flex-direction: column;
  padding: 32px 28px; border-right: 1px solid var(--line);
  background: rgba(11, 12, 14, 0.7); backdrop-filter: blur(8px);
  z-index: 50;
}

.monogram {
  font-family: var(--serif); font-size: 28px; color: var(--text);
  border: 1px solid var(--line); width: 48px; height: 48px;
  display: grid; place-items: center; border-radius: 10px;
  transition: border-color 0.25s, color 0.25s;
}
.monogram:hover { border-color: var(--accent); color: var(--accent); text-decoration: none; }

.rail-nav { display: flex; flex-direction: column; gap: 2px; margin-top: 48px; }
.rail-nav a {
  display: flex; align-items: baseline; gap: 12px;
  padding: 7px 10px; margin-left: -10px; border-radius: 6px;
  color: var(--text-dim); font-size: 13.5px; letter-spacing: 0.02em;
  transition: color 0.2s, background 0.2s;
}
.rail-nav a .idx { font-family: var(--mono); font-size: 10.5px; color: var(--accent); opacity: 0.55; }
.rail-nav a:hover { color: var(--text); text-decoration: none; background: var(--bg-raise); }
.rail-nav a.active { color: var(--text); background: var(--accent-soft); }
.rail-nav a.active .idx { opacity: 1; }

.rail-foot { margin-top: auto; display: flex; gap: 16px; }
.rail-foot a { color: var(--text-dim); transition: color 0.2s, transform 0.2s; }
.rail-foot a:hover { color: var(--accent); transform: translateY(-2px); }

/* mobile menu button */
.menu-toggle {
  display: none; position: fixed; top: 18px; right: 18px; z-index: 60;
  width: 44px; height: 44px; border-radius: 10px;
  background: var(--bg-raise); border: 1px solid var(--line); cursor: pointer;
}
.menu-toggle span {
  display: block; width: 18px; height: 2px; background: var(--text);
  margin: 3px auto; transition: transform 0.25s, opacity 0.25s;
}
.menu-toggle[aria-expanded="true"] span:first-child { transform: translateY(4px) rotate(45deg); }
.menu-toggle[aria-expanded="true"] span:last-child { transform: translateY(-4px) rotate(-45deg); }

/* ---------------- layout ---------------- */
main {
  margin-left: var(--rail-w);
  padding: 0 48px;
  position: relative; z-index: 3;
}
.section, .hero { max-width: var(--maxw); margin: 0 auto; }

/* ---------------- hero ---------------- */
.hero { padding: 120px 0 72px; }

.kicker {
  font-family: var(--mono); font-size: 12.5px; letter-spacing: 0.14em;
  text-transform: uppercase; color: var(--accent); margin: 0 0 20px;
}
.kicker::before { content: "— "; color: var(--text-dim); }

.hero h1 {
  font-family: var(--serif); font-weight: 400;
  font-size: clamp(44px, 7vw, 84px); line-height: 1.02;
  letter-spacing: -0.01em; margin: 0 0 28px;
}
.hero h1 em, .contact-big em { font-style: italic; color: var(--accent); }

.hero-sub {
  font-size: 19px; color: var(--text-dim); max-width: 560px; margin: 0 0 32px;
}
.hero-sub strong { color: var(--text); font-weight: 600; }

.hero-cta { display: flex; flex-wrap: wrap; gap: 14px; }

.btn {
  display: inline-block; padding: 12px 22px; border-radius: 8px;
  font-size: 14.5px; font-weight: 500; letter-spacing: 0.02em;
  border: 1px solid var(--line); transition: all 0.22s;
}
.btn:hover { text-decoration: none; transform: translateY(-2px); }
.btn-solid { background: var(--accent); color: #18120a; border-color: var(--accent); }
.btn-solid:hover { box-shadow: 0 6px 24px rgba(217, 151, 76, 0.35); }
.btn-ghost { color: var(--text); }
.btn-ghost:hover { border-color: var(--accent); color: var(--accent); }
.btn-sm { padding: 8px 14px; font-size: 13px; }

.stat-row {
  display: grid; grid-template-columns: repeat(4, 1fr); gap: 1px;
  background: var(--line); border: 1px solid var(--line); border-radius: 12px;
  overflow: hidden; margin: 56px 0 0;
}
.stat-row > div { background: var(--bg-raise); padding: 20px 22px; }
.stat-row dt {
  font-family: var(--serif); font-size: 34px; color: var(--accent); line-height: 1;
}
.stat-row dd { margin: 8px 0 0; font-size: 13px; color: var(--text-dim); }

/* ---------------- sections ---------------- */
.section { padding: 72px 0; border-top: 1px solid var(--line); }

.section-head { display: flex; align-items: baseline; gap: 16px; margin-bottom: 40px; }
.section-head .num { font-family: var(--mono); font-size: 13px; color: var(--accent); }
.section-head h2 {
  font-family: var(--serif); font-weight: 400; font-size: clamp(30px, 4vw, 42px);
  margin: 0; letter-spacing: -0.01em;
}

/* ---------------- about ---------------- */
.about-grid { display: grid; grid-template-columns: 1.4fr 1fr; gap: 48px; align-items: start; }
.lede { font-size: 20px; line-height: 1.55; color: var(--text); }
.about-text p { color: var(--text-dim); }
.about-text .lede { color: var(--text); }

.about-card {
  margin: 0; border: 1px solid var(--line); border-radius: 14px;
  overflow: hidden; background: var(--bg-raise);
}
.about-card img { width: 100%; display: block; aspect-ratio: 4 / 5; object-fit: cover; object-position: center 22%; filter: saturate(0.9); }
.about-card figcaption { padding: 18px; border-top: 1px solid var(--line); }
.about-card pre { margin: 0; overflow-x: auto; }
.about-card code { font-family: var(--mono); font-size: 11.5px; line-height: 1.7; color: var(--text-dim); }
.about-card .c { color: #5c6066; }
.about-card .k { color: var(--accent); }
.about-card .s { color: #a8b88a; }

/* ---------------- timeline ---------------- */
.timeline { list-style: none; margin: 0; padding: 0; }
.t-item {
  display: grid; grid-template-columns: 180px 1fr; gap: 32px;
  padding: 28px 0; border-bottom: 1px dashed var(--line); position: relative;
}
.t-item:last-child { border-bottom: none; }

.t-meta { display: flex; flex-direction: column; gap: 4px; }
.t-dates { font-family: var(--mono); font-size: 12.5px; color: var(--accent); letter-spacing: 0.03em; }
.t-loc { font-family: var(--mono); font-size: 11.5px; color: var(--text-dim); }

.t-body h3 { margin: 0 0 4px; font-size: 19px; font-weight: 600; letter-spacing: -0.01em; }
.t-org { margin: 0 0 12px; font-size: 14px; color: var(--text-dim); font-style: italic; }
.t-body ul { margin: 0; padding-left: 18px; color: var(--text-dim); font-size: 15px; }
.t-body li { margin-bottom: 6px; }
.t-body li::marker { color: var(--accent); }
.t-compact h3 { color: var(--text-dim); font-size: 16px; }

/* ---------------- projects ---------------- */
.project {
  border: 1px solid var(--line); border-radius: 14px; background: var(--bg-raise);
  padding: 28px; transition: border-color 0.25s, transform 0.25s, box-shadow 0.25s;
}
.project:hover {
  border-color: rgba(217, 151, 76, 0.5); transform: translateY(-3px);
  box-shadow: 0 14px 40px rgba(0, 0, 0, 0.45);
}
.project h3 { font-family: var(--serif); font-weight: 400; font-size: 26px; margin: 10px 0 10px; }
.project p { color: var(--text-dim); font-size: 15px; margin: 0 0 16px; }

.flagship {
  margin-bottom: 24px;
  background: linear-gradient(135deg, var(--bg-raise-2), var(--bg-raise) 55%);
  border-color: rgba(217, 151, 76, 0.35);
  position: relative; overflow: hidden;
}
.flagship::after {
  content: "MAiQ"; position: absolute; right: -10px; bottom: -34px;
  font-family: var(--serif); font-size: 130px; color: var(--accent); opacity: 0.06;
  pointer-events: none;
}
.flagship h3 { font-size: 32px; }

.p-tag {
  font-family: var(--mono); font-size: 11px; letter-spacing: 0.12em;
  text-transform: uppercase; color: var(--accent);
}

.project-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 24px; }

.chips { list-style: none; display: flex; flex-wrap: wrap; gap: 8px; margin: 0; padding: 0; }
.chips li {
  font-family: var(--mono); font-size: 11.5px; color: var(--text-dim);
  border: 1px solid var(--line); border-radius: 99px; padding: 4px 11px;
}

/* ---------------- skills ledger ---------------- */
.skill-ledger { margin: 0; border: 1px solid var(--line); border-radius: 14px; overflow: hidden; }
.skill-row {
  display: grid; grid-template-columns: 230px 1fr;
  border-bottom: 1px solid var(--line); background: var(--bg-raise);
}
.skill-row:last-child { border-bottom: none; }
.skill-row:nth-child(even) { background: var(--bg); }
.skill-row dt {
  padding: 18px 22px; font-family: var(--mono); font-size: 12.5px;
  letter-spacing: 0.06em; text-transform: uppercase; color: var(--accent);
  border-right: 1px solid var(--line);
}
.skill-row dd { margin: 0; padding: 18px 22px; font-size: 14.5px; color: var(--text-dim); }

/* ---------------- education / credentials / referrals ---------------- */
.edu-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 24px; }
.cred-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px; }

.edu-card {
  border: 1px solid var(--line); border-radius: 14px; background: var(--bg-raise);
  padding: 24px;
}
.edu-card h3 { font-size: 17px; margin: 8px 0 4px; display: flex; flex-wrap: wrap; gap: 10px; align-items: baseline; }
.edu-card p { color: var(--text-dim); font-size: 14px; margin: 6px 0 0; }
.edu-card ul { margin: 10px 0 0; padding-left: 18px; color: var(--text-dim); font-size: 14px; }
.edu-card li { margin-bottom: 8px; }
.edu-card li::marker { color: var(--accent); }
.edu-card strong { color: var(--text); }

.ref-card .btn { margin-top: 14px; }

/* ---------------- contact ---------------- */
.contact { padding-bottom: 48px; }
.contact-big {
  font-family: var(--serif); font-size: clamp(30px, 4.5vw, 50px);
  line-height: 1.15; margin: 0 0 32px; letter-spacing: -0.01em;
}
.foot {
  display: flex; justify-content: space-between; align-items: baseline;
  margin-top: 72px; padding-top: 24px; border-top: 1px solid var(--line);
  color: var(--text-dim); font-size: 13px;
}
.foot-mono { font-family: var(--mono); font-size: 11.5px; }

/* ---------------- motion ---------------- */
@keyframes rise {
  from { opacity: 0; transform: translateY(22px); }
  to { opacity: 1; transform: none; }
}
.reveal-load { animation: rise 0.7s cubic-bezier(0.2, 0.7, 0.2, 1) both; animation-delay: calc(var(--d) * 0.12s); }

.reveal { opacity: 0; transform: translateY(24px); transition: opacity 0.6s, transform 0.6s cubic-bezier(0.2, 0.7, 0.2, 1); }
.reveal.in { opacity: 1; transform: none; }

@media (prefers-reduced-motion: reduce) {
  .reveal-load, .reveal { animation: none; opacity: 1; transform: none; transition: none; }
}

/* ---------------- responsive ---------------- */
@media (max-width: 1080px) {
  .stat-row { grid-template-columns: 1fr 1fr; }
  .cred-grid { grid-template-columns: 1fr; }
}

@media (max-width: 900px) {
  .rail {
    transform: translateX(-100%); transition: transform 0.3s ease;
    width: min(300px, 80vw); box-shadow: 24px 0 60px rgba(0,0,0,0.5);
  }
  body.nav-open .rail { transform: none; }
  .menu-toggle { display: block; }
  main { margin-left: 0; padding: 0 24px; }
  .hero { padding-top: 88px; }
  .about-grid, .project-grid, .edu-grid { grid-template-columns: 1fr; }
  .t-item { grid-template-columns: 1fr; gap: 8px; padding: 22px 0; }
  .t-meta { flex-direction: row; gap: 14px; align-items: baseline; }
  .skill-row { grid-template-columns: 1fr; }
  .skill-row dt { border-right: none; border-bottom: 1px dashed var(--line); padding-bottom: 10px; }
  .foot { flex-direction: column; gap: 6px; }
}