/* ============================================================
   Krishnakumar KR — Portfolio
   Central design file. All tokens live here.
   System: pure black / white · Inter · IBM Plex Mono accents
   ============================================================ */

/* ---- Fonts (self-hosted, no CDN) -------------------------- */
@font-face {
  font-family: 'Inter';
  font-style: normal;
  font-weight: 100 900;
  font-display: swap;
  src: url('/fonts/inter.woff2') format('woff2');
}
@font-face {
  font-family: 'IBM Plex Mono';
  font-style: normal;
  font-weight: 400;
  font-display: swap;
  src: url('/fonts/plex-mono-400.woff2') format('woff2');
}
@font-face {
  font-family: 'IBM Plex Mono';
  font-style: normal;
  font-weight: 500;
  font-display: swap;
  src: url('/fonts/plex-mono-500.woff2') format('woff2');
}

/* ---- Design tokens --------------------------------------- */
:root {
  /* Colour — pure black / white only */
  --paper:        #ffffff;
  --ink:          #0a0a0a;
  --ink-soft:     #565656;
  --ink-faint:    #8e8e8e;
  --line:         #e7e7e7;
  --line-mid:     #d4d4d4;
  --hover:        #f5f5f3;
  --invert-bg:    #0a0a0a;
  --invert-ink:   #ffffff;
  --invert-soft:  #a0a0a0;
  --invert-faint: #6a6a6a;
  --invert-line:  #262626;
  --invert-hover: #161616;

  /* Type */
  --sans: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  --mono: 'IBM Plex Mono', ui-monospace, 'SF Mono', Menlo, monospace;

  /* Fluid scale */
  --t-meta:    0.75rem;
  --t-small:   0.8125rem;
  --t-body:    1.0625rem;
  --t-lead:    clamp(1.15rem, 0.9rem + 1vw, 1.5rem);
  --t-proj:    clamp(1.6rem, 1.1rem + 1.9vw, 2.45rem);
  --t-sect:    clamp(1.9rem, 1.3rem + 2.6vw, 3.1rem);
  --t-stmt:    clamp(1.7rem, 1rem + 3vw, 3.1rem);
  --t-name:    clamp(2.7rem, 1.3rem + 5.6vw, 5.9rem);
  --t-num:     clamp(2.8rem, 1rem + 7vw, 6.5rem);

  /* Layout */
  --maxw:    1280px;
  --gutter:  clamp(20px, 5.2vw, 76px);
  --ease:    cubic-bezier(0.22, 1, 0.36, 1);
}

/* ---- Reset ----------------------------------------------- */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

html { scroll-behavior: smooth; -webkit-text-size-adjust: 100%; }
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  * { animation-duration: 0.01ms !important; transition-duration: 0.01ms !important; }
}

body {
  font-family: var(--sans);
  font-size: var(--t-body);
  line-height: 1.62;
  font-feature-settings: "cv05" 1, "cv11" 1, "ss03" 1;
  color: var(--ink);
  background: var(--paper);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  overflow-x: hidden;
}

a { color: inherit; text-decoration: none; }
img, svg { display: block; max-width: 100%; }
::selection { background: var(--ink); color: var(--paper); }

/* ---- Shared layout -------------------------------------- */
.wrap {
  max-width: var(--maxw);
  margin-inline: auto;
  padding-inline: var(--gutter);
}

.section { padding-block: clamp(72px, 9vw, 150px); }
.section--tight { padding-block: clamp(56px, 7vw, 110px); }
section[id], header[id] { scroll-margin-top: 66px; }

.mono {
  font-family: var(--mono);
  font-weight: 400;
  letter-spacing: 0.02em;
}

.eyebrow {
  font-family: var(--mono);
  font-size: var(--t-meta);
  letter-spacing: 0.22em;
  text-transform: uppercase;
  color: var(--ink-faint);
}

/* ============================================================
   NAV
   ============================================================ */
.nav {
  position: fixed;
  inset: 0 0 auto 0;
  z-index: 100;
  background: rgba(255, 255, 255, 0.82);
  backdrop-filter: blur(14px) saturate(1.4);
  -webkit-backdrop-filter: blur(14px) saturate(1.4);
  border-bottom: 1px solid transparent;
  transition: border-color 0.3s var(--ease), background 0.3s var(--ease);
}
.nav.is-stuck { border-bottom-color: var(--line); }

.nav__inner {
  max-width: var(--maxw);
  margin-inline: auto;
  padding: 15px var(--gutter);
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.nav__brand {
  font-family: var(--mono);
  font-weight: 500;
  font-size: 0.9rem;
  letter-spacing: 0.04em;
  display: flex;
  align-items: center;
  gap: 9px;
}
.nav__brand .dot {
  width: 7px; height: 7px;
  background: var(--ink);
  border-radius: 50%;
  display: inline-block;
}

.nav__links {
  display: flex;
  align-items: center;
  gap: clamp(18px, 2.4vw, 38px);
}
.nav__links a {
  font-family: var(--mono);
  font-size: var(--t-small);
  color: var(--ink-soft);
  letter-spacing: 0.01em;
  transition: color 0.2s var(--ease);
}
.nav__links a:hover { color: var(--ink); }
.nav__links .nav__num { color: var(--ink-faint); margin-right: 5px; }

.nav__cta {
  font-family: var(--mono);
  font-size: var(--t-small);
  border: 1px solid var(--ink);
  padding: 8px 16px;
  color: var(--ink);
  transition: background 0.22s var(--ease), color 0.22s var(--ease);
}
.nav__cta:hover { background: var(--ink); color: var(--paper); }

.nav__menu-links { display: contents; }
.nav__burger { display: none; }

/* ============================================================
   HERO
   ============================================================ */
.hero {
  position: relative;
  padding-top: clamp(130px, 18vh, 210px);
  padding-bottom: clamp(60px, 8vw, 120px);
  overflow: hidden;
}
.hero__grid-bg {
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(var(--line) 1px, transparent 1px),
    linear-gradient(90deg, var(--line) 1px, transparent 1px);
  background-size: 72px 72px;
  -webkit-mask-image: radial-gradient(ellipse 75% 65% at 70% 18%, #000 0%, transparent 78%);
          mask-image: radial-gradient(ellipse 75% 65% at 70% 18%, #000 0%, transparent 78%);
  opacity: 0.55;
  pointer-events: none;
}

.hero__inner { position: relative; }

.hero__eyebrow {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-bottom: clamp(26px, 4vw, 46px);
}
.hero__eyebrow .rule {
  flex: 0 0 44px;
  height: 1px;
  background: var(--ink);
}

.hero__name {
  font-size: var(--t-name);
  font-weight: 600;
  line-height: 0.98;
  letter-spacing: -0.035em;
  margin-bottom: clamp(26px, 4vw, 44px);
}

.hero__statement {
  font-size: var(--t-stmt);
  font-weight: 500;
  line-height: 1.16;
  letter-spacing: -0.02em;
  max-width: 19ch;
}
.hero__statement em {
  font-style: normal;
  position: relative;
  white-space: nowrap;
}
.hero__statement em::after {
  content: "";
  position: absolute;
  left: 0; right: 0; bottom: 0.04em;
  height: 0.085em;
  background: var(--ink);
}

.hero__sub {
  margin-top: clamp(26px, 3.5vw, 40px);
  max-width: 56ch;
  color: var(--ink-soft);
  font-size: var(--t-lead);
  line-height: 1.55;
}
.hero__sub strong { color: var(--ink); font-weight: 600; }
.hero__sub a {
  color: var(--ink);
  text-decoration: underline;
  text-underline-offset: 3px;
  text-decoration-thickness: 1px;
  text-decoration-color: rgba(10, 10, 10, 0.35);
  transition: text-decoration-color 0.2s ease;
}
.hero__sub a:hover { text-decoration-color: var(--ink); }

.hero__actions {
  margin-top: clamp(32px, 4vw, 48px);
  display: flex;
  flex-wrap: wrap;
  gap: 14px;
}
.btn {
  font-family: var(--mono);
  font-size: var(--t-small);
  letter-spacing: 0.02em;
  padding: 13px 22px;
  display: inline-flex;
  align-items: center;
  gap: 10px;
  border: 1px solid var(--ink);
  transition: background 0.24s var(--ease), color 0.24s var(--ease), transform 0.24s var(--ease);
}
.btn .arr { transition: transform 0.28s var(--ease); }
.btn--solid { background: var(--ink); color: var(--paper); }
.btn--solid:hover { background: var(--paper); color: var(--ink); }
.btn--solid:hover .arr { transform: translate(3px, -3px); }
.btn--ghost:hover { background: var(--ink); color: var(--paper); }
.btn--ghost:hover .arr { transform: translateY(3px); }

/* ---- Stat band ------------------------------------------ */
.stats {
  border-top: 1px solid var(--ink);
  display: grid;
  grid-template-columns: repeat(4, 1fr);
}
.stat {
  padding: clamp(26px, 3vw, 42px) clamp(16px, 2vw, 30px) clamp(24px, 3vw, 38px) 0;
  border-right: 1px solid var(--line);
}
.stat:last-child { border-right: none; }
.stat__num {
  font-size: clamp(2.3rem, 1.2rem + 3vw, 3.8rem);
  font-weight: 600;
  letter-spacing: -0.03em;
  line-height: 1;
  font-variant-numeric: tabular-nums;
}
.stat__label {
  margin-top: 12px;
  font-family: var(--mono);
  font-size: var(--t-small);
  line-height: 1.45;
  color: var(--ink-soft);
}

/* ============================================================
   SECTION HEADER
   ============================================================ */
.s-head {
  display: grid;
  grid-template-columns: auto 1fr;
  gap: clamp(20px, 4vw, 60px);
  align-items: end;
  padding-bottom: clamp(34px, 4vw, 56px);
  border-bottom: 1px solid var(--ink);
  margin-bottom: clamp(20px, 3vw, 34px);
}
.s-head__num {
  font-family: var(--mono);
  font-size: var(--t-num);
  font-weight: 400;
  line-height: 0.8;
  color: var(--line-mid);
  letter-spacing: -0.02em;
}
.s-head__txt { min-width: 0; }
.s-head__title {
  font-size: var(--t-sect);
  font-weight: 600;
  letter-spacing: -0.03em;
  line-height: 1.04;
}
.s-head__desc {
  margin-top: 14px;
  max-width: 54ch;
  color: var(--ink-soft);
  font-size: 1rem;
}

/* ============================================================
   PROJECT LIST
   ============================================================ */
.projects { border-top: 1px solid var(--line); }

.project {
  display: grid;
  grid-template-columns: 0.92fr 1.5fr;
  gap: clamp(20px, 4vw, 70px);
  padding: clamp(34px, 4vw, 56px) 0;
  border-bottom: 1px solid var(--line);
  position: relative;
  transition: background 0.3s var(--ease);
}
a.project:hover { background: var(--hover); }
a.project { margin-inline: calc(-1 * clamp(14px, 2vw, 28px)); padding-inline: clamp(14px, 2vw, 28px); }

.project__id {
  display: flex;
  align-items: baseline;
  gap: 14px;
  margin-bottom: 16px;
}
.project__idx {
  font-family: var(--mono);
  font-size: var(--t-small);
  color: var(--ink-faint);
}
.project__tag {
  font-family: var(--mono);
  font-size: var(--t-meta);
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--ink-soft);
}
.project__flag {
  font-family: var(--mono);
  font-size: var(--t-meta);
  letter-spacing: 0.12em;
  text-transform: uppercase;
  background: var(--ink);
  color: var(--paper);
  padding: 3px 8px 2px;
}

.project__name {
  font-size: var(--t-proj);
  font-weight: 600;
  letter-spacing: -0.03em;
  line-height: 1.04;
  display: flex;
  align-items: baseline;
  gap: 12px;
  flex-wrap: wrap;
}
.project__url {
  font-family: var(--mono);
  font-size: var(--t-small);
  color: var(--ink-soft);
  display: inline-flex;
  align-items: center;
  gap: 6px;
  margin-top: 16px;
  border-bottom: 1px solid var(--line-mid);
  padding-bottom: 3px;
  width: fit-content;
  transition: border-color 0.22s var(--ease), color 0.22s var(--ease);
}
a.project:hover .project__url { color: var(--ink); border-color: var(--ink); }
.project__url .arr { transition: transform 0.28s var(--ease); }
a.project:hover .project__url .arr { transform: translate(3px, -3px); }

.project__body {
  display: flex;
  flex-direction: column;
  gap: 22px;
}
.project__desc { color: var(--ink-soft); }
.project__desc strong { color: var(--ink); font-weight: 600; }

.stack {
  display: flex;
  flex-wrap: wrap;
  gap: 7px;
}
.stack span {
  font-family: var(--mono);
  font-size: var(--t-meta);
  letter-spacing: 0.01em;
  color: var(--ink-soft);
  border: 1px solid var(--line-mid);
  padding: 5px 9px 4px;
  white-space: nowrap;
}

/* ============================================================
   APPROACH (inverted)
   ============================================================ */
.invert {
  background: var(--invert-bg);
  color: var(--invert-ink);
}
.invert ::selection { background: var(--paper); color: var(--ink); }

.approach__head {
  display: grid;
  grid-template-columns: auto 1fr;
  gap: clamp(20px, 4vw, 60px);
  align-items: start;
}
.approach__num {
  font-family: var(--mono);
  font-size: var(--t-num);
  line-height: 0.8;
  color: var(--invert-line);
}
.approach__eyebrow {
  font-family: var(--mono);
  font-size: var(--t-meta);
  letter-spacing: 0.22em;
  text-transform: uppercase;
  color: var(--invert-faint);
  margin-bottom: 26px;
}
.approach__stmt {
  font-size: var(--t-stmt);
  font-weight: 500;
  letter-spacing: -0.022em;
  line-height: 1.16;
  max-width: 20ch;
}
.approach__stmt em {
  font-style: normal;
  color: var(--invert-soft);
}
.approach__lead {
  margin-top: 28px;
  max-width: 58ch;
  color: var(--invert-soft);
  font-size: var(--t-lead);
}

.principles {
  margin-top: clamp(44px, 6vw, 86px);
  border-top: 1px solid var(--invert-line);
  display: grid;
  grid-template-columns: repeat(4, 1fr);
}
.principle {
  padding: clamp(26px, 2.6vw, 40px) clamp(18px, 1.8vw, 28px) clamp(30px, 3vw, 48px) 0;
  border-right: 1px solid var(--invert-line);
}
.principle:last-child { border-right: none; padding-right: 0; }
.principle__no {
  font-family: var(--mono);
  font-size: var(--t-small);
  color: var(--invert-faint);
  margin-bottom: 18px;
}
.principle__t {
  font-size: 1.18rem;
  font-weight: 600;
  letter-spacing: -0.018em;
  margin-bottom: 10px;
}
.principle__d {
  font-size: 0.95rem;
  line-height: 1.55;
  color: var(--invert-soft);
}

.approach__close {
  margin-top: clamp(40px, 5vw, 70px);
  padding-top: clamp(30px, 3vw, 44px);
  border-top: 1px solid var(--invert-line);
  font-size: var(--t-lead);
  max-width: 64ch;
}
.approach__close strong { font-weight: 600; }

/* ============================================================
   EXPERIENCE
   ============================================================ */
.xp { border-top: 1px solid var(--line); }
.xp__row {
  display: grid;
  grid-template-columns: 0.42fr 0.78fr 1.4fr;
  gap: clamp(16px, 3vw, 54px);
  padding: clamp(26px, 3vw, 40px) 0;
  border-bottom: 1px solid var(--line);
  align-items: start;
}
.xp__years {
  font-family: var(--mono);
  font-size: var(--t-small);
  color: var(--ink-faint);
  padding-top: 5px;
}
.xp__org { min-width: 0; }
.xp__co {
  font-size: 1.28rem;
  font-weight: 600;
  letter-spacing: -0.02em;
  line-height: 1.18;
}
.xp__role {
  margin-top: 7px;
  font-family: var(--mono);
  font-size: var(--t-small);
  color: var(--ink-soft);
}
.xp__desc {
  color: var(--ink-soft);
  font-size: 1rem;
  padding-top: 3px;
}

/* ============================================================
   CONTACT (inverted) + FOOTER
   ============================================================ */
.contact { padding-block: clamp(76px, 9vw, 150px); }
.contact__eyebrow {
  font-family: var(--mono);
  font-size: var(--t-meta);
  letter-spacing: 0.22em;
  text-transform: uppercase;
  color: var(--invert-faint);
  margin-bottom: 30px;
}
.contact__big {
  font-size: var(--t-name);
  font-weight: 600;
  letter-spacing: -0.035em;
  line-height: 1;
}
.contact__line {
  margin-top: 26px;
  max-width: 50ch;
  color: var(--invert-soft);
  font-size: var(--t-lead);
}

/* ---- Contact: details + form ---- */
.contact__body {
  margin-top: clamp(40px, 5vw, 72px);
  padding-top: clamp(36px, 4vw, 56px);
  border-top: 1px solid var(--invert-line);
  display: grid;
  grid-template-columns: 0.8fr 1.2fr;
  gap: clamp(34px, 5vw, 92px);
}

.contact__details { display: flex; flex-direction: column; }
.cd {
  padding: 17px 0;
  border-bottom: 1px solid var(--invert-line);
}
.cd:first-child { padding-top: 0; }
.cd:last-child { border-bottom: none; }
.cd__k {
  font-family: var(--mono);
  font-size: var(--t-meta);
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--invert-faint);
  margin-bottom: 9px;
}
.cd__v {
  font-family: var(--mono);
  font-size: 0.97rem;
  color: var(--invert-ink);
  transition: color 0.2s var(--ease);
  word-break: break-word;
}
a.cd__v { display: inline-flex; align-items: center; gap: 7px; }
a.cd__v:hover { color: var(--invert-soft); }
a.cd__v .arr { transition: transform 0.28s var(--ease); }
a.cd__v:hover .arr { transform: translate(3px, -3px); }

.contact__form { display: flex; flex-direction: column; }
.field { display: flex; flex-direction: column; margin-bottom: 18px; }
.field label {
  font-family: var(--mono);
  font-size: var(--t-meta);
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--invert-faint);
  margin-bottom: 9px;
}
.field input,
.field textarea {
  width: 100%;
  background: transparent;
  border: 1px solid var(--invert-line);
  color: var(--invert-ink);
  font-family: var(--sans);
  font-size: 1rem;
  line-height: 1.5;
  padding: 13px 15px;
  border-radius: 0;
  -webkit-appearance: none;
  appearance: none;
  transition: border-color 0.2s var(--ease), background 0.2s var(--ease);
}
.field textarea { resize: vertical; min-height: 134px; }
.field input::placeholder,
.field textarea::placeholder { color: var(--invert-faint); }
.field input:focus,
.field textarea:focus {
  outline: none;
  border-color: var(--invert-ink);
  background: var(--invert-hover);
}

.cf-hp {
  position: absolute !important;
  left: -9999px !important;
  width: 1px; height: 1px;
  opacity: 0; pointer-events: none;
}

.cf-foot {
  display: flex;
  align-items: center;
  gap: 16px 20px;
  flex-wrap: wrap;
  margin-top: 6px;
}
.cf-submit {
  font-family: var(--mono);
  font-size: var(--t-small);
  letter-spacing: 0.02em;
  background: var(--invert-ink);
  color: var(--invert-bg);
  border: 1px solid var(--invert-ink);
  padding: 14px 26px;
  cursor: pointer;
  display: inline-flex;
  align-items: center;
  gap: 10px;
  transition: background 0.24s var(--ease), color 0.24s var(--ease), opacity 0.2s var(--ease);
}
.cf-submit .arr { transition: transform 0.28s var(--ease); }
.cf-submit:hover:not(:disabled) { background: transparent; color: var(--invert-ink); }
.cf-submit:hover:not(:disabled) .arr { transform: translate(3px, -3px); }
.cf-submit:disabled { opacity: 0.5; cursor: progress; }

.cf-status {
  font-family: var(--mono);
  font-size: var(--t-small);
  line-height: 1.4;
  color: var(--invert-faint);
}
.cf-status.is-strong { color: var(--invert-ink); }

.footer {
  border-top: 1px solid var(--invert-line);
  padding: 28px var(--gutter);
  max-width: var(--maxw);
  margin-inline: auto;
  display: flex;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 12px;
  font-family: var(--mono);
  font-size: var(--t-small);
  color: var(--invert-faint);
}

/* ============================================================
   MOTION — reveal on scroll / load
   ============================================================ */
.reveal {
  opacity: 0;
  transform: translateY(24px);
  transition: opacity 0.8s var(--ease), transform 0.8s var(--ease);
}
.reveal.in { opacity: 1; transform: none; }
.reveal[data-d="1"] { transition-delay: 0.08s; }
.reveal[data-d="2"] { transition-delay: 0.16s; }
.reveal[data-d="3"] { transition-delay: 0.24s; }
.reveal[data-d="4"] { transition-delay: 0.32s; }
.reveal[data-d="5"] { transition-delay: 0.40s; }

/* ============================================================
   RESPONSIVE
   ============================================================ */
@media (max-width: 1080px) {
  .project { grid-template-columns: 1fr; gap: 24px; }
  .xp__row { grid-template-columns: 0.5fr 1.5fr; }
  .xp__desc { grid-column: 2; }
}

@media (max-width: 860px) {
  .nav__menu-links {
    display: none;
    position: absolute;
    inset: 100% 0 auto 0;
    background: var(--paper);
    border-bottom: 1px solid var(--line);
    flex-direction: column;
    align-items: flex-start;
    gap: 0;
    padding: 8px var(--gutter) 22px;
  }
  .nav.is-open .nav__menu-links { display: flex; }
  .nav__links { display: contents; }
  .nav__menu-links a,
  .nav__menu-links .nav__cta {
    width: 100%;
    padding-block: 13px;
  }
  .nav__menu-links .nav__cta { margin-top: 10px; text-align: center; justify-content: center; }
  .nav__burger {
    display: flex;
    flex-direction: column;
    gap: 5px;
    background: none;
    border: none;
    cursor: pointer;
    padding: 6px;
  }
  .nav__burger span {
    width: 22px; height: 1.5px;
    background: var(--ink);
    transition: transform 0.28s var(--ease), opacity 0.2s var(--ease);
  }
  .nav.is-open .nav__burger span:nth-child(1) { transform: translateY(6.5px) rotate(45deg); }
  .nav.is-open .nav__burger span:nth-child(2) { opacity: 0; }
  .nav.is-open .nav__burger span:nth-child(3) { transform: translateY(-6.5px) rotate(-45deg); }

  .stats { grid-template-columns: 1fr 1fr; }
  .stat:nth-child(2) { border-right: none; }
  .stat:nth-child(1), .stat:nth-child(2) { border-bottom: 1px solid var(--line); }
  .stat { padding-right: 0; }

  .principles { grid-template-columns: 1fr 1fr; }
  .principle:nth-child(2) { border-right: none; padding-right: 0; }
  .principle:nth-child(1), .principle:nth-child(2) { border-bottom: 1px solid var(--invert-line); }

  .contact__body { grid-template-columns: 1fr; gap: 38px; }

  .s-head { grid-template-columns: 1fr; gap: 14px; }
  .s-head__num { font-size: clamp(2.6rem, 14vw, 4rem); }
  .approach__head { grid-template-columns: 1fr; gap: 14px; }
}

@media (max-width: 560px) {
  .xp__row { grid-template-columns: 1fr; gap: 10px; }
  .xp__desc { grid-column: 1; }
  .stats { grid-template-columns: 1fr; }
  .stat { border-right: none; border-bottom: 1px solid var(--line); }
  .stat:last-child { border-bottom: none; }
  .principles { grid-template-columns: 1fr; }
  .principle { border-right: none; border-bottom: 1px solid var(--invert-line); padding-right: 0; }
  .principle:last-child { border-bottom: none; }
  .hero__statement { max-width: 100%; }
}