/* ==========================================================================
   Sagar Arora — Portfolio
   Vanilla CSS. No frameworks, no build step.

   1.  Design tokens
   2.  Reset & base
   3.  Layout primitives
   4.  Background decor
   5.  Buttons & chips
   6.  Header & navigation
   7.  Hero
   8.  Sections & headings
   9.  About
   10. Skills
   11. Timeline / experience
   12. Case studies
   13. Education & credentials
   14. Contact
   15. Footer & back-to-top
   16. Motion / reveal
   17. Responsive
   18. Print
   ========================================================================== */


/* ==========================================================================
   1. DESIGN TOKENS
   ========================================================================== */

:root {
  /* Type scale — fluid */
  --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto,
               'Helvetica Neue', Arial, sans-serif;
  --font-mono: 'JetBrains Mono', ui-monospace, SFMono-Regular, 'SF Mono',
               Menlo, Consolas, monospace;

  --text-xs:   0.75rem;
  --text-sm:   0.8125rem;
  --text-base: 0.9375rem;
  --text-md:   1.0625rem;
  --text-lg:   clamp(1.125rem, 1.05rem + 0.4vw, 1.3125rem);
  --text-xl:   clamp(1.375rem, 1.2rem + 0.9vw, 1.875rem);
  --text-2xl:  clamp(1.75rem, 1.4rem + 1.7vw, 2.75rem);
  --text-hero: clamp(2.5rem, 1.55rem + 4.4vw, 5rem);

  /* Spacing */
  --sp-1: 0.25rem;  --sp-2: 0.5rem;   --sp-3: 0.75rem;  --sp-4: 1rem;
  --sp-5: 1.5rem;   --sp-6: 2rem;     --sp-7: 2.75rem;  --sp-8: 3.5rem;
  --sp-9: 5rem;     --sp-10: 7rem;

  --section-pad: clamp(4.5rem, 8vw, 8rem);
  --wrap: 1140px;
  --wrap-narrow: 860px;

  --radius-sm: 8px;
  --radius:    14px;
  --radius-lg: 20px;
  --radius-pill: 999px;

  --header-h: 68px;

  --ease: cubic-bezier(0.22, 0.68, 0.35, 1);
  --ease-out: cubic-bezier(0.16, 1, 0.3, 1);
  --dur: 0.32s;

  --z-decor: 0;
  --z-content: 1;
  --z-header: 100;
  --z-top: 90;
}


/* ---------- Dark theme (default) ---------- */
:root,
[data-theme='dark'] {
  --bg:            #08090c;
  --bg-alt:        #0b0d11;
  --surface:       #101318;
  --surface-2:     #151920;
  --surface-hi:    #1b2028;

  --border:        #1f242c;
  --border-strong: #2c333d;

  --text:          #e9edf2;
  --text-muted:    #98a2ae;
  --text-dim:      #7d8794;   /* >=4.8:1 on every surface it lands on */

  --accent:        #a3e635;   /* lime-400 — high contrast on near-black */
  --accent-soft:   #bef264;
  --accent-ink:    #0b1200;   /* text placed on accent fills */
  --accent-alt:    #a78bfa;   /* violet-400 */
  --accent-alt-ink:#10091f;

  --ring:          rgba(163, 230, 53, 0.45);
  --glow-a:        rgba(163, 230, 53, 0.14);
  --glow-b:        rgba(167, 139, 250, 0.14);
  --grid-line:     rgba(255, 255, 255, 0.035);

  --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.5);
  --shadow:    0 8px 26px -12px rgba(0, 0, 0, 0.75);
  --shadow-lg: 0 28px 60px -28px rgba(0, 0, 0, 0.85);

  --chip-bg:     rgba(255, 255, 255, 0.04);
  --chip-border: rgba(255, 255, 255, 0.08);
  --code-bg:     rgba(163, 230, 53, 0.09);
  --code-border: rgba(163, 230, 53, 0.26);
  --code-text:   #bef264;
  color-scheme: dark;
}


/* ---------- Light theme ---------- */
[data-theme='light'] {
  --bg:            #fbfbfd;
  --bg-alt:        #f4f5f8;
  --surface:       #ffffff;
  --surface-2:     #f7f8fa;
  --surface-hi:    #eef0f4;

  --border:        #e5e7ec;
  --border-strong: #d3d7de;

  --text:          #0e1116;
  --text-muted:    #59626f;
  --text-dim:      #656f7c;   /* >=4.8:1 on every surface it lands on */

  --accent:        #15803d;   /* green-700 — 4.5:1 on white */
  --accent-soft:   #166534;
  --accent-ink:    #ffffff;
  --accent-alt:    #6d28d9;
  --accent-alt-ink:#ffffff;

  --ring:          rgba(21, 128, 61, 0.35);
  --glow-a:        rgba(21, 128, 61, 0.09);
  --glow-b:        rgba(109, 40, 217, 0.08);
  --grid-line:     rgba(15, 23, 42, 0.045);

  --shadow-sm: 0 1px 2px rgba(15, 23, 42, 0.06);
  --shadow:    0 10px 28px -14px rgba(15, 23, 42, 0.18);
  --shadow-lg: 0 30px 60px -30px rgba(15, 23, 42, 0.24);

  --chip-bg:     rgba(15, 23, 42, 0.035);
  --chip-border: rgba(15, 23, 42, 0.08);
  --code-bg:     rgba(21, 128, 61, 0.08);
  --code-border: rgba(21, 128, 61, 0.22);
  --code-text:   #15803d;
  color-scheme: light;
}


/* ==========================================================================
   2. RESET & BASE
   ========================================================================== */

*, *::before, *::after { box-sizing: border-box; }

* { margin: 0; }

html {
  -webkit-text-size-adjust: 100%;
  scroll-behavior: smooth;
  scroll-padding-top: calc(var(--header-h) + 1.5rem);
}

body {
  font-family: var(--font-sans);
  font-size: var(--text-base);
  line-height: 1.65;
  color: var(--text);
  background-color: var(--bg);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  text-rendering: optimizeLegibility;
  overflow-x: hidden;
  transition: background-color var(--dur) var(--ease), color var(--dur) var(--ease);
}

body.nav-open { overflow: hidden; }

img, svg, video { display: block; max-width: 100%; }
svg { flex-shrink: 0; }

h1, h2, h3, h4 {
  line-height: 1.15;
  letter-spacing: -0.022em;
  font-weight: 650;
  text-wrap: balance;
}

p { text-wrap: pretty; }

a {
  color: inherit;
  text-decoration: none;
}

ul, ol { list-style: none; padding: 0; }

button, input, textarea, select {
  font: inherit;
  color: inherit;
}

:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 3px;
  border-radius: 4px;
}

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

strong { font-weight: 640; color: var(--text); }

code, kbd, pre { font-family: var(--font-mono); font-size: 0.9em; }

.skip-link {
  /* Fixed, not absolute: guarantees it is on-screen when focused no matter
     how far down the page the visitor had scrolled. */
  position: fixed;
  top: -100px;
  left: 1rem;
  z-index: 999;
  padding: 0.7rem 1.1rem;
  background: var(--accent);
  color: var(--accent-ink);
  font-weight: 600;
  font-size: var(--text-sm);
  border-radius: var(--radius-sm);
  transition: top 0.2s var(--ease);
}
.skip-link:focus { top: 1rem; }


/* ==========================================================================
   3. LAYOUT PRIMITIVES
   ========================================================================== */

.wrap {
  width: 100%;
  max-width: var(--wrap);
  margin-inline: auto;
  padding-inline: clamp(1.25rem, 4vw, 2.5rem);
}

.section {
  position: relative;
  z-index: var(--z-content);
  padding-block: var(--section-pad);
  scroll-margin-top: var(--header-h);
}

.section--alt { background-color: var(--bg-alt); }

.section-head { margin-bottom: clamp(2.5rem, 5vw, 4rem); }

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 0.6rem;
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  font-weight: 500;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--text-dim);
  margin-bottom: 1rem;
}

.eyebrow-num {
  color: var(--accent);
  padding: 0.15rem 0.45rem;
  border: 1px solid var(--code-border);
  border-radius: var(--radius-sm);
  background: var(--code-bg);
}

.section-title {
  font-size: var(--text-2xl);
  max-width: 22ch;
}

.section-sub {
  margin-top: 1.1rem;
  max-width: 58ch;
  font-size: var(--text-md);
  color: var(--text-muted);
  line-height: 1.7;
}

.card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: clamp(1.35rem, 2.4vw, 1.9rem);
  box-shadow: var(--shadow-sm);
  transition: border-color var(--dur) var(--ease),
              transform var(--dur) var(--ease),
              box-shadow var(--dur) var(--ease),
              background-color var(--dur) var(--ease);
}

.grad-text {
  background: linear-gradient(100deg, var(--accent) 0%, var(--accent-alt) 100%);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
  -webkit-text-fill-color: transparent;
}

/* Safety net: if background-clip:text is unsupported the text would render
   transparent and vanish, so fall back to a solid accent colour. */
@supports not ((-webkit-background-clip: text) or (background-clip: text)) {
  .grad-text,
  .hero-name {
    background: none;
    color: var(--text);
    -webkit-text-fill-color: currentColor;
  }
  .hero-name { color: var(--accent); }
}


/* ==========================================================================
   4. BACKGROUND DECOR
   ========================================================================== */

.bg-decor {
  position: fixed;
  inset: 0;
  z-index: var(--z-decor);
  pointer-events: none;
  overflow: hidden;
}

.bg-grid {
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(var(--grid-line) 1px, transparent 1px),
    linear-gradient(90deg, var(--grid-line) 1px, transparent 1px);
  background-size: 68px 68px;
  mask-image: radial-gradient(ellipse 90% 60% at 50% 0%, #000 20%, transparent 78%);
  -webkit-mask-image: radial-gradient(ellipse 90% 60% at 50% 0%, #000 20%, transparent 78%);
}

.bg-glow {
  position: absolute;
  border-radius: 50%;
  filter: blur(120px);
  opacity: 0.9;
}
.bg-glow--a {
  width: 46rem; height: 46rem;
  top: -22rem; right: -14rem;
  background: radial-gradient(circle, var(--glow-a), transparent 68%);
}
.bg-glow--b {
  width: 38rem; height: 38rem;
  top: 34rem; left: -16rem;
  background: radial-gradient(circle, var(--glow-b), transparent 68%);
}


/* ==========================================================================
   5. BUTTONS & CHIPS
   ========================================================================== */

.btn {
  --btn-pad-y: 0.78rem;
  --btn-pad-x: 1.4rem;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.55rem;
  padding: var(--btn-pad-y) var(--btn-pad-x);
  font-size: var(--text-sm);
  font-weight: 600;
  letter-spacing: -0.005em;
  line-height: 1.2;
  border-radius: var(--radius-pill);
  border: 1px solid transparent;
  cursor: pointer;
  white-space: nowrap;
  transition: transform 0.18s var(--ease),
              box-shadow 0.24s var(--ease),
              background-color 0.24s var(--ease),
              border-color 0.24s var(--ease),
              color 0.24s var(--ease);
}

.btn:hover { transform: translateY(-2px); }
.btn:active { transform: translateY(0); }

.btn--primary {
  background: var(--accent);
  color: var(--accent-ink);
  box-shadow: 0 10px 30px -12px var(--ring);
}
.btn--primary:hover {
  background: var(--accent-soft);
  box-shadow: 0 16px 38px -12px var(--ring);
}

.btn--ghost {
  background: transparent;
  color: var(--text);
  border-color: var(--border-strong);
}
.btn--ghost:hover {
  background: var(--surface-2);
  border-color: var(--accent);
  color: var(--accent);
}

.btn--quiet {
  background: transparent;
  color: var(--text-muted);
  padding-inline: 0.9rem;
}
.btn--quiet:hover { color: var(--accent); }

.btn--sm { --btn-pad-y: 0.55rem; --btn-pad-x: 1rem; font-size: var(--text-xs); }
.btn--block { width: 100%; }

.chip-list {
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem;
}

.chip {
  display: inline-flex;
  align-items: center;
  padding: 0.32rem 0.65rem;
  font-size: var(--text-xs);
  font-weight: 500;
  line-height: 1.4;
  color: var(--text-muted);
  background: var(--chip-bg);
  border: 1px solid var(--chip-border);
  border-radius: var(--radius-sm);
  white-space: nowrap;
  transition: color 0.2s var(--ease), border-color 0.2s var(--ease),
              background-color 0.2s var(--ease);
}

.chip:hover {
  color: var(--accent);
  border-color: var(--code-border);
  background: var(--code-bg);
}

.chip--strong {
  color: var(--text);
  font-weight: 600;
  background: var(--code-bg);
  border-color: var(--code-border);
}
.chip--strong:hover { color: var(--accent); }

.chip-list--sm .chip { font-size: 0.6875rem; padding: 0.26rem 0.55rem; }


/* ==========================================================================
   6. HEADER & NAVIGATION
   ========================================================================== */

.site-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: var(--z-header);
  height: var(--header-h);
  display: flex;
  align-items: center;
  background: color-mix(in srgb, var(--bg) 78%, transparent);
  backdrop-filter: blur(16px) saturate(150%);
  -webkit-backdrop-filter: blur(16px) saturate(150%);
  border-bottom: 1px solid transparent;
  transition: border-color 0.3s var(--ease),
              background-color 0.3s var(--ease),
              box-shadow 0.3s var(--ease);
}

.site-header.is-stuck {
  border-bottom-color: var(--border);
  box-shadow: 0 6px 24px -18px rgba(0, 0, 0, 0.9);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
}

.brand {
  display: flex;
  align-items: center;
  gap: 0.7rem;
  min-width: 0;
}

.brand-mark {
  display: grid;
  place-items: center;
  width: 36px; height: 36px;
  flex-shrink: 0;
  font-family: var(--font-mono);
  font-size: 0.8125rem;
  font-weight: 500;
  letter-spacing: -0.03em;
  color: var(--accent-ink);
  background: var(--accent);
  border-radius: 10px;
  box-shadow: 0 6px 18px -8px var(--ring);
}

.brand-text { display: flex; flex-direction: column; line-height: 1.2; min-width: 0; }

.brand-name {
  font-size: 0.9375rem;
  font-weight: 650;
  letter-spacing: -0.02em;
}

.brand-role {
  font-family: var(--font-mono);
  font-size: 0.625rem;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--text-dim);
  white-space: nowrap;
}

.nav-list {
  display: flex;
  align-items: center;
  gap: 0.15rem;
}

.nav-link {
  position: relative;
  display: block;
  padding: 0.45rem 0.7rem;
  font-size: var(--text-sm);
  font-weight: 500;
  color: var(--text-muted);
  border-radius: var(--radius-sm);
  transition: color 0.2s var(--ease), background-color 0.2s var(--ease);
}

.nav-link:hover { color: var(--text); background: var(--surface-2); }

.nav-link::after {
  content: '';
  position: absolute;
  left: 0.7rem; right: 0.7rem;
  bottom: 0.15rem;
  height: 1.5px;
  background: var(--accent);
  border-radius: 2px;
  transform: scaleX(0);
  transform-origin: left;
  transition: transform 0.3s var(--ease-out);
}

.nav-link.is-active { color: var(--text); }
.nav-link.is-active::after { transform: scaleX(1); }

.header-actions { display: flex; align-items: center; gap: 0.5rem; }

.icon-btn {
  display: grid;
  place-items: center;
  width: 36px; height: 36px;
  padding: 0;
  color: var(--text-muted);
  background: transparent;
  border: 1px solid var(--border);
  border-radius: 10px;
  cursor: pointer;
  transition: color 0.2s var(--ease), border-color 0.2s var(--ease),
              background-color 0.2s var(--ease);
}

.icon-btn:hover {
  color: var(--accent);
  border-color: var(--border-strong);
  background: var(--surface-2);
}

.icon-btn .icon { grid-area: 1 / 1; transition: transform 0.4s var(--ease), opacity 0.3s var(--ease); }

[data-theme='dark']  .icon-moon,
[data-theme='light'] .icon-sun { opacity: 0; transform: rotate(-90deg) scale(0.5); }
[data-theme='dark']  .icon-sun,
[data-theme='light'] .icon-moon { opacity: 1; transform: rotate(0) scale(1); }

.nav-toggle { display: none; }

.burger {
  display: flex;
  flex-direction: column;
  justify-content: center;
  gap: 4px;
  width: 16px; height: 12px;
}
.burger span {
  display: block;
  height: 1.5px;
  width: 100%;
  background: currentColor;
  border-radius: 2px;
  transition: transform 0.3s var(--ease), opacity 0.2s var(--ease);
}
[aria-expanded='true'] .burger span:nth-child(1) { transform: translateY(5.5px) rotate(45deg); }
[aria-expanded='true'] .burger span:nth-child(2) { opacity: 0; }
[aria-expanded='true'] .burger span:nth-child(3) { transform: translateY(-5.5px) rotate(-45deg); }

.scroll-progress {
  position: absolute;
  left: 0; bottom: -1px;
  height: 2px;
  width: 100%;
  transform: scaleX(0);
  transform-origin: left;
  background: linear-gradient(90deg, var(--accent), var(--accent-alt));
  opacity: 0;
  transition: opacity 0.3s var(--ease);
}
.site-header.is-stuck .scroll-progress { opacity: 1; }


/* ==========================================================================
   7. HERO
   ========================================================================== */

.hero {
  position: relative;
  z-index: var(--z-content);
  min-height: 100svh;
  display: flex;
  align-items: center;
  padding-top: calc(var(--header-h) + 3.5rem);
  padding-bottom: 6rem;
  scroll-margin-top: var(--header-h);
}

.hero-inner { max-width: 940px; }

.status-pill {
  display: inline-flex;
  align-items: center;
  gap: 0.6rem;
  padding: 0.4rem 0.95rem 0.4rem 0.75rem;
  margin-bottom: 1.75rem;
  font-size: var(--text-xs);
  font-weight: 500;
  letter-spacing: 0.01em;
  color: var(--text-muted);
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-pill);
  box-shadow: var(--shadow-sm);
}

.status-dot {
  position: relative;
  width: 7px; height: 7px;
  flex-shrink: 0;
  border-radius: 50%;
  background: var(--accent);
  box-shadow: 0 0 0 0 var(--ring);
  animation: pulse 2.6s var(--ease) infinite;
}

@keyframes pulse {
  0%   { box-shadow: 0 0 0 0 var(--ring); }
  70%  { box-shadow: 0 0 0 8px transparent; }
  100% { box-shadow: 0 0 0 0 transparent; }
}

.hero-name {
  display: block;
  font-size: var(--text-hero);
  font-weight: 700;
  letter-spacing: -0.042em;
  line-height: 0.98;
  background: linear-gradient(170deg, var(--text) 25%, color-mix(in srgb, var(--text) 52%, transparent) 100%);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
}

.hero-role {
  margin-top: 1.1rem;
  font-size: var(--text-xl);
  font-weight: 600;
  letter-spacing: -0.025em;
  color: var(--text);
}
.hero-sep { color: var(--text-dim); margin-inline: 0.35rem; font-weight: 400; }

.hero-lede {
  margin-top: 1.5rem;
  max-width: 62ch;
  font-size: var(--text-md);
  line-height: 1.75;
  color: var(--text-muted);
}

.hero-cta {
  display: flex;
  flex-wrap: wrap;
  gap: 0.7rem;
  margin-top: 2.25rem;
}

.stat-strip {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 1px;
  margin-top: 3.5rem;
  background: var(--border);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  overflow: hidden;
}

.stat {
  padding: 1.1rem 1.25rem;
  background: var(--surface);
  transition: background-color 0.3s var(--ease);
}
.stat:hover { background: var(--surface-2); }

.stat-label {
  font-family: var(--font-mono);
  font-size: 0.625rem;
  letter-spacing: 0.11em;
  text-transform: uppercase;
  color: var(--text-dim);
}

.stat-value {
  margin-top: 0.3rem;
  font-size: clamp(1.4rem, 1.2rem + 0.7vw, 1.85rem);
  font-weight: 680;
  letter-spacing: -0.035em;
  line-height: 1.1;
}
.stat-value .unit {
  font-size: 0.5em;
  font-weight: 500;
  color: var(--text-dim);
  letter-spacing: -0.01em;
  margin-left: 0.15rem;
}

.hero-scroll {
  position: absolute;
  left: 50%;
  bottom: 2rem;
  transform: translateX(-50%);
  display: none;
  flex-direction: column;
  align-items: center;
  gap: 0.6rem;
}
.hero-scroll-line {
  width: 1px; height: 44px;
  background: linear-gradient(var(--border-strong), transparent);
  animation: scrollHint 2.4s var(--ease) infinite;
}
.hero-scroll-text {
  font-family: var(--font-mono);
  font-size: 0.625rem;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--text-dim);
}
@keyframes scrollHint {
  0%, 100% { opacity: 0.35; transform: scaleY(0.6); transform-origin: top; }
  50%      { opacity: 1;    transform: scaleY(1);   transform-origin: top; }
}


/* ==========================================================================
   9. ABOUT
   ========================================================================== */

.about-grid {
  display: grid;
  grid-template-columns: minmax(0, 1.55fr) minmax(0, 1fr);
  gap: clamp(2rem, 4vw, 3.5rem);
  align-items: start;
}

.about-prose { max-width: 66ch; }
.about-prose p { color: var(--text-muted); line-height: 1.78; }
.about-prose p + p { margin-top: 1.15rem; }
.about-prose strong { color: var(--text); }

.about-aside {
  display: flex;
  flex-direction: column;
  gap: 1rem;
  position: sticky;
  top: calc(var(--header-h) + 1.5rem);
}

.about-aside .card:hover { border-color: var(--border-strong); }

.card-title {
  font-size: var(--text-xs);
  font-weight: 600;
  font-family: var(--font-mono);
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--text-dim);
  margin-bottom: 0.85rem;
}

.fact-card { padding: 1.35rem 1.4rem; }

.fact-role {
  font-size: var(--text-md);
  font-weight: 620;
  letter-spacing: -0.02em;
  line-height: 1.3;
}
.fact-org { margin-top: 0.2rem; font-size: var(--text-sm); color: var(--text-muted); }
.fact-meta {
  margin-top: 0.6rem;
  font-family: var(--font-mono);
  font-size: 0.6875rem;
  color: var(--text-dim);
}

.tick-list { display: flex; flex-direction: column; gap: 0.6rem; }
.tick-list li {
  position: relative;
  padding-left: 1.4rem;
  font-size: var(--text-sm);
  color: var(--text-muted);
  line-height: 1.55;
}
.tick-list li::before {
  content: '';
  position: absolute;
  left: 0; top: 0.52em;
  width: 6px; height: 6px;
  border-radius: 2px;
  background: var(--accent);
  transform: rotate(45deg);
}


/* ==========================================================================
   10. SKILLS
   ========================================================================== */

.skills-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 1rem;
}

.skill-group:hover {
  transform: translateY(-3px);
  border-color: var(--border-strong);
  box-shadow: var(--shadow);
}

.skill-group-title {
  display: flex;
  align-items: center;
  gap: 0.6rem;
  margin-bottom: 1.15rem;
  font-size: var(--text-md);
  font-weight: 620;
  letter-spacing: -0.02em;
}

.skill-icon {
  display: grid;
  place-items: center;
  width: 26px; height: 26px;
  flex-shrink: 0;
  font-family: var(--font-mono);
  font-size: 0.625rem;
  font-weight: 500;
  color: var(--accent);
  background: var(--code-bg);
  border: 1px solid var(--code-border);
  border-radius: 7px;
}

.tooling-row {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.75rem 1.5rem;
  margin-top: 1.5rem;
  padding: 1.1rem 1.4rem;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
}

.tooling-label {
  font-family: var(--font-mono);
  font-size: 0.625rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--text-dim);
  white-space: nowrap;
}

.tooling-list {
  display: flex;
  flex-wrap: wrap;
  gap: 0.35rem 1.15rem;
  font-size: var(--text-sm);
  color: var(--text-muted);
}
.tooling-list li { position: relative; }
.tooling-list li + li::before {
  content: '·';
  position: absolute;
  left: -0.65rem;
  color: var(--text-dim);
}


/* ==========================================================================
   11. TIMELINE / EXPERIENCE
   ========================================================================== */

.timeline {
  position: relative;
  display: flex;
  flex-direction: column;
  gap: 1.25rem;
  padding-left: 1.9rem;
}

.timeline::before {
  content: '';
  position: absolute;
  left: 6px; top: 0.6rem; bottom: 0.6rem;
  width: 1px;
  background: linear-gradient(var(--border-strong), var(--border) 15%, var(--border) 85%, transparent);
}

.tl-item { position: relative; }

.tl-marker {
  position: absolute;
  left: -1.9rem;
  top: 1.75rem;
  display: grid;
  place-items: center;
  width: 13px; height: 13px;
  background: var(--bg);
  border-radius: 50%;
}
.section--alt .tl-marker { background: var(--bg-alt); }

.tl-dot {
  width: 9px; height: 9px;
  border-radius: 50%;
  background: var(--accent);
  box-shadow: 0 0 0 4px var(--bg), 0 0 14px -2px var(--ring);
  transition: transform 0.3s var(--ease);
}
.section--alt .tl-dot { box-shadow: 0 0 0 4px var(--bg-alt), 0 0 14px -2px var(--ring); }
.tl-dot--muted { background: var(--text-dim); box-shadow: 0 0 0 4px var(--bg); }
.tl-item:hover .tl-dot { transform: scale(1.35); }

.tl-card:hover {
  border-color: var(--border-strong);
  box-shadow: var(--shadow);
  transform: translateY(-2px);
}

.tl-head {
  display: flex;
  flex-wrap: wrap;
  align-items: flex-start;
  justify-content: space-between;
  gap: 0.5rem 1.5rem;
  margin-bottom: 1.1rem;
  padding-bottom: 1.1rem;
  border-bottom: 1px solid var(--border);
}

.tl-role {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.6rem;
  font-size: var(--text-lg);
  font-weight: 650;
  letter-spacing: -0.025em;
}

.tl-org {
  margin-top: 0.3rem;
  font-size: var(--text-sm);
  color: var(--text-muted);
}

.tl-badge {
  display: inline-flex;
  align-items: center;
  padding: 0.2rem 0.55rem;
  font-family: var(--font-mono);
  font-size: 0.625rem;
  font-weight: 500;
  letter-spacing: 0.04em;
  color: var(--text-muted);
  background: var(--chip-bg);
  border: 1px solid var(--chip-border);
  border-radius: var(--radius-sm);
  white-space: nowrap;
}
.tl-badge--accent {
  color: var(--accent);
  background: var(--code-bg);
  border-color: var(--code-border);
}

.tl-meta {
  display: flex;
  flex-direction: column;
  align-items: flex-end;
  gap: 0.15rem;
  text-align: right;
  flex-shrink: 0;
}

.tl-period {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: var(--text);
  white-space: nowrap;
}

.tl-place {
  font-size: var(--text-xs);
  color: var(--text-dim);
  white-space: nowrap;
}

.bullet-list { display: flex; flex-direction: column; gap: 0.7rem; }

.bullet-list li {
  position: relative;
  padding-left: 1.35rem;
  font-size: var(--text-base);
  line-height: 1.68;
  color: var(--text-muted);
}

.bullet-list li::before {
  content: '';
  position: absolute;
  left: 0.15rem; top: 0.68em;
  width: 5px; height: 5px;
  border-radius: 50%;
  background: var(--accent);
  opacity: 0.75;
}

.tl-card .chip-list { margin-top: 1.25rem; }


/* ==========================================================================
   12. CASE STUDIES
   ========================================================================== */

.case {
  padding: clamp(1.6rem, 3.2vw, 2.75rem);
  margin-bottom: 1.25rem;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-sm);
  transition: border-color var(--dur) var(--ease), box-shadow var(--dur) var(--ease);
}
.case:hover { border-color: var(--border-strong); box-shadow: var(--shadow); }

.case-head {
  padding-bottom: 1.6rem;
  margin-bottom: 1.6rem;
  border-bottom: 1px solid var(--border);
}

.case-kicker {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.09em;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: 0.7rem;
}

.case-title {
  font-size: var(--text-xl);
  max-width: 30ch;
  letter-spacing: -0.032em;
}

.case-summary {
  margin-top: 0.85rem;
  max-width: 62ch;
  font-size: var(--text-md);
  line-height: 1.65;
  color: var(--text-muted);
}

.case-head .chip-list { margin-top: 1.15rem; }

.case-body {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: clamp(1.25rem, 2.6vw, 2.25rem);
}

.case-label {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  margin-bottom: 0.65rem;
  font-family: var(--font-mono);
  font-size: 0.6875rem;
  font-weight: 500;
  letter-spacing: 0.11em;
  text-transform: uppercase;
  color: var(--text-dim);
}
.case-label::after {
  content: '';
  flex: 1;
  height: 1px;
  background: var(--border);
}

.case-block p {
  font-size: var(--text-base);
  line-height: 1.72;
  color: var(--text-muted);
}
.case-block strong { color: var(--text); }

.metric-row {
  display: flex;
  flex-wrap: wrap;
  gap: 0.6rem;
  margin-top: 1.35rem;
}

.metric {
  display: flex;
  flex-direction: column;
  gap: 0.1rem;
  padding: 0.75rem 1.05rem;
  background: var(--surface-2);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
}

.metric-value {
  font-size: var(--text-lg);
  font-weight: 680;
  letter-spacing: -0.035em;
  line-height: 1.1;
  color: var(--accent);
}

.metric-label {
  font-family: var(--font-mono);
  font-size: 0.625rem;
  letter-spacing: 0.09em;
  text-transform: uppercase;
  color: var(--text-dim);
}

.case--feature {
  background:
    linear-gradient(180deg, var(--code-bg), transparent 55%),
    var(--surface);
  border-color: var(--code-border);
}

.feature-split {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(0, 1.35fr);
  gap: clamp(1.75rem, 3.5vw, 3rem);
  align-items: start;
}

.feature-split .case-head {
  padding-bottom: 0;
  margin-bottom: 0;
  border-bottom: none;
}

.feature-split .case-body {
  grid-template-columns: minmax(0, 1fr);
  gap: 1.5rem;
  padding-top: 0.3rem;
}

.feature-split .case-block { position: relative; }
.feature-split .case-block + .case-block {
  padding-top: 1.5rem;
  border-top: 1px solid var(--border);
}


/* ==========================================================================
   13. EDUCATION & CREDENTIALS
   ========================================================================== */

.edu-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(270px, 1fr));
  gap: clamp(1.5rem, 3vw, 2.5rem);
  align-items: start;
}

.col-title {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  font-weight: 500;
  letter-spacing: 0.13em;
  text-transform: uppercase;
  color: var(--text-dim);
  margin-bottom: 1.1rem;
  padding-bottom: 0.75rem;
  border-bottom: 1px solid var(--border);
}

.edu-col { display: flex; flex-direction: column; gap: 0.75rem; }

.edu-card:hover { border-color: var(--border-strong); transform: translateY(-2px); }

.edu-degree {
  font-size: var(--text-md);
  font-weight: 620;
  letter-spacing: -0.02em;
  line-height: 1.35;
}
.edu-org { margin-top: 0.3rem; font-size: var(--text-sm); color: var(--text-muted); }
.edu-meta {
  margin-top: 0.5rem;
  font-family: var(--font-mono);
  font-size: 0.6875rem;
  color: var(--text-dim);
}

.cert-list { display: flex; flex-direction: column; gap: 0.6rem; }

.cert-item {
  display: flex;
  align-items: center;
  gap: 0.9rem;
  padding: 0.95rem 1.1rem;
}

.cert-item:hover { border-color: var(--border-strong); transform: translateX(3px); }

.cert-icon {
  display: grid;
  place-items: center;
  width: 34px; height: 34px;
  flex-shrink: 0;
  color: var(--accent);
  background: var(--code-bg);
  border: 1px solid var(--code-border);
  border-radius: 9px;
}

.cert-body { display: flex; flex-direction: column; min-width: 0; }
.cert-name {
  font-size: var(--text-sm);
  font-weight: 600;
  letter-spacing: -0.01em;
}
.cert-issuer {
  font-size: var(--text-xs);
  color: var(--text-dim);
}

.cert-item--award .cert-icon {
  color: var(--accent-alt);
  background: color-mix(in srgb, var(--accent-alt) 12%, transparent);
  border-color: color-mix(in srgb, var(--accent-alt) 30%, transparent);
}


/* ==========================================================================
   14. CONTACT
   ========================================================================== */

.contact-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(0, 1.05fr);
  gap: clamp(1.5rem, 3vw, 2.5rem);
  align-items: start;
}

.contact-channels { display: flex; flex-direction: column; gap: 0.7rem; }

.channel {
  display: flex;
  align-items: center;
  gap: 1rem;
  padding: 1.05rem 1.25rem;
}
.channel[href]:hover { border-color: var(--accent); transform: translateX(4px); }

.channel-icon {
  display: grid;
  place-items: center;
  width: 40px; height: 40px;
  flex-shrink: 0;
  color: var(--text-muted);
  background: var(--surface-2);
  border: 1px solid var(--border);
  border-radius: 11px;
  transition: color 0.24s var(--ease), background-color 0.24s var(--ease),
              border-color 0.24s var(--ease);
}
.channel[href]:hover .channel-icon {
  color: var(--accent-ink);
  background: var(--accent);
  border-color: var(--accent);
}

.channel-body { display: flex; flex-direction: column; min-width: 0; flex: 1; }

.channel-label {
  font-family: var(--font-mono);
  font-size: 0.625rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--text-dim);
}

.channel-value {
  font-size: var(--text-sm);
  font-weight: 500;
  color: var(--text);
  overflow-wrap: anywhere;
}

/* Real control, so always visible — a button you can only reveal on hover is
   undiscoverable and unreachable on touch. */
.channel-action {
  flex-shrink: 0;
  padding: 0.4rem 0.7rem;
  font-family: var(--font-mono);
  font-size: 0.625rem;
  font-weight: 500;
  letter-spacing: 0.09em;
  text-transform: uppercase;
  color: var(--text-muted);
  background: var(--surface-2);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: color 0.2s var(--ease), background-color 0.2s var(--ease),
              border-color 0.2s var(--ease);
}
.channel-action:hover {
  color: var(--accent);
  border-color: var(--code-border);
  background: var(--code-bg);
}
.channel.is-copied { border-color: var(--accent); }
.channel-action.is-copied {
  color: var(--accent-ink);
  background: var(--accent);
  border-color: var(--accent);
}

.contact-form { display: flex; flex-direction: column; gap: 1rem; }

.form-title { font-size: var(--text-lg); letter-spacing: -0.025em; }
.form-sub { margin-top: -0.6rem; font-size: var(--text-sm); color: var(--text-dim); }

.field { display: flex; flex-direction: column; gap: 0.4rem; }

.field label {
  font-size: var(--text-xs);
  font-weight: 600;
  letter-spacing: 0.05em;
  text-transform: uppercase;
  color: var(--text-muted);
}

.field .optional {
  font-weight: 400;
  text-transform: none;
  letter-spacing: 0;
  color: var(--text-dim);
}

.field input,
.field textarea {
  width: 100%;
  padding: 0.75rem 0.9rem;
  font-size: var(--text-base);
  color: var(--text);
  background: var(--surface-2);
  border: 1px solid var(--border);
  border-radius: 10px;
  transition: border-color 0.2s var(--ease), box-shadow 0.2s var(--ease),
              background-color 0.2s var(--ease);
}

.field textarea { resize: vertical; min-height: 118px; line-height: 1.6; }

.field input::placeholder,
.field textarea::placeholder { color: var(--text-dim); opacity: 0.75; }

.field input:focus,
.field textarea:focus {
  outline: none;
  border-color: var(--accent);
  background: var(--surface);
  box-shadow: 0 0 0 3px var(--code-bg);
}

.field input[aria-invalid='true'],
.field textarea[aria-invalid='true'] { border-color: #ef4444; }
[data-theme='dark'] .field input[aria-invalid='true'],
[data-theme='dark'] .field textarea[aria-invalid='true'] { border-color: #f87171; }

.field-error {
  font-size: var(--text-xs);
  color: #ef4444;
  min-height: 0;
}
[data-theme='dark'] .field-error { color: #f87171; }
.field-error:empty { display: none; }

.hp {
  position: absolute;
  left: -9999px;
  width: 1px; height: 1px;
  overflow: hidden;
}

#cfSubmit.is-busy { pointer-events: none; opacity: 0.72; }

.form-status {
  font-size: var(--text-sm);
  min-height: 1.2em;
  padding-left: 1.1rem;
  position: relative;
}
.form-status:not(:empty)::before {
  content: '';
  position: absolute;
  left: 0; top: 0.42em;
  width: 7px; height: 7px;
  border-radius: 50%;
  background: currentColor;
}
.form-status.is-ok { color: var(--accent); }
.form-status.is-error { color: #ef4444; }
[data-theme='dark'] .form-status.is-error { color: #f87171; }


/* ==========================================================================
   15. FOOTER & BACK-TO-TOP
   ========================================================================== */

.site-footer {
  position: relative;
  z-index: var(--z-content);
  padding-block: 2.75rem;
  border-top: 1px solid var(--border);
  background: var(--bg-alt);
}

.footer-inner {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 1.25rem;
}

.footer-copy {
  font-size: var(--text-xs);
  color: var(--text-dim);
  max-width: 46ch;
  line-height: 1.6;
}

.footer-links { display: flex; flex-wrap: wrap; gap: 0.25rem 1.1rem; }
.footer-links a {
  /* Padded so the tap target clears the 24px WCAG minimum on touch. */
  display: inline-block;
  padding-block: 0.3rem;
  font-size: var(--text-sm);
  color: var(--text-muted);
  transition: color 0.2s var(--ease);
}
.footer-links a:hover { color: var(--accent); }

.to-top {
  position: fixed;
  right: clamp(1rem, 3vw, 1.75rem);
  bottom: clamp(1rem, 3vw, 1.75rem);
  z-index: var(--z-top);
  display: grid;
  place-items: center;
  width: 42px; height: 42px;
  color: var(--text-muted);
  background: var(--surface);
  border: 1px solid var(--border-strong);
  border-radius: 12px;
  box-shadow: var(--shadow);
  cursor: pointer;
  opacity: 0;
  visibility: hidden;
  transform: translateY(12px) scale(0.9);
  transition: opacity 0.3s var(--ease), transform 0.3s var(--ease),
              visibility 0.3s, color 0.2s var(--ease), border-color 0.2s var(--ease);
}
.to-top.is-visible { opacity: 1; visibility: visible; transform: translateY(0) scale(1); }
.to-top:hover { color: var(--accent); border-color: var(--accent); }


/* ==========================================================================
   16. MOTION / REVEAL
   ========================================================================== */

/* Scoped to .js (set by an inline script in <head>) so that the page is fully
   visible when JavaScript is unavailable or fails. */
.js [data-reveal] {
  opacity: 0;
  transform: translateY(18px);
  transition: opacity 0.7s var(--ease-out), transform 0.7s var(--ease-out);
  will-change: opacity, transform;
}
.js [data-reveal].is-visible { opacity: 1; transform: none; }
.js [data-reveal][data-reveal-delay='1'] { transition-delay: 0.08s; }
.js [data-reveal][data-reveal-delay='2'] { transition-delay: 0.16s; }
.js [data-reveal][data-reveal-delay='3'] { transition-delay: 0.24s; }
.js [data-reveal][data-reveal-delay='4'] { transition-delay: 0.32s; }
.js [data-reveal][data-reveal-delay='5'] { transition-delay: 0.4s; }

/* Respect the OS "reduce motion" setting: show everything immediately. */
html.no-motion *,
html.no-motion *::before,
html.no-motion *::after {
  transition: none !important;
  animation: none !important;
}
html.no-motion [data-reveal] { opacity: 1; transform: none; }


/* ==========================================================================
   17. RESPONSIVE
   ========================================================================== */

@media (max-width: 1080px) {
  .case-body { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .case-body .case-block:last-child { grid-column: 1 / -1; }
  .feature-split { grid-template-columns: minmax(0, 1fr); }
  .feature-split .case-head {
    padding-bottom: 1.6rem;
    margin-bottom: 0;
    border-bottom: 1px solid var(--border);
  }
  .feature-split .case-body { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .feature-split .case-block:last-child { grid-column: 1 / -1; }
}

@media (max-width: 960px) {
  :root { --header-h: 62px; }

  .nav-toggle { display: grid; }

  .header-resume { display: none; }

  .nav {
    position: fixed;
    inset: var(--header-h) 0 auto 0;
    padding: 1.25rem clamp(1.25rem, 4vw, 2.5rem) 1.75rem;
    background: var(--bg);
    border-bottom: 1px solid var(--border);
    box-shadow: var(--shadow-lg);
    transform: translateY(-12px);
    opacity: 0;
    visibility: hidden;
    transition: opacity 0.28s var(--ease), transform 0.28s var(--ease), visibility 0.28s;
  }
  .nav.is-open { opacity: 1; visibility: visible; transform: translateY(0); }

  .nav-list { flex-direction: column; align-items: stretch; gap: 0.15rem; }
  .nav-link { padding: 0.8rem 0.9rem; font-size: var(--text-md); }
  .nav-link::after { left: 0.9rem; right: auto; width: 18px; bottom: 0.45rem; }
  .nav-link.is-active { background: var(--surface-2); }

  /* No-JS fallback: the hamburger cannot work, so instead of hiding the links
     behind a dead button, expose them as a horizontally scrollable strip. */
  html:not(.js) .nav {
    opacity: 1;
    visibility: visible;
    transform: none;
    padding: 0.55rem clamp(1.25rem, 4vw, 2.5rem);
    box-shadow: none;
    overflow-x: auto;
    -webkit-overflow-scrolling: touch;
    scrollbar-width: none;
  }
  html:not(.js) .nav::-webkit-scrollbar { display: none; }
  html:not(.js) .nav-list { flex-direction: row; gap: 0.15rem; }
  html:not(.js) .nav-link {
    padding: 0.5rem 0.7rem;
    font-size: var(--text-sm);
    white-space: nowrap;
  }
  html:not(.js) .nav-link::after { display: none; }
  html:not(.js) .nav-toggle { display: none; }

  .about-grid { grid-template-columns: minmax(0, 1fr); }
  .about-aside { position: static; }

  .contact-grid { grid-template-columns: minmax(0, 1fr); }
}

@media (max-width: 760px) {
  .stat-strip { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .case-body,
  .feature-split .case-body { grid-template-columns: minmax(0, 1fr); }
  .case-body .case-block:last-child,
  .feature-split .case-block:last-child { grid-column: auto; }
  .hero { min-height: auto; padding-bottom: 5rem; }
  .hero-scroll { display: none; }
}

@media (max-width: 620px) {
  .brand-role { display: none; }
  .stat-strip { grid-template-columns: minmax(0, 1fr); }
  .tl-head { flex-direction: column; align-items: flex-start; }
  .tl-meta { flex-direction: row; align-items: center; gap: 0.75rem; text-align: left; }
  .hero-cta .btn { flex: 1 1 auto; }
  .footer-inner { flex-direction: column; align-items: flex-start; }
}

@media (max-width: 420px) {
  .tooling-list li + li::before { display: none; }
}


/* ==========================================================================
   18. PRINT — "Print to PDF" gives a clean one-page-ish CV
   ========================================================================== */

@media print {
  :root { --text: #000; --text-muted: #222; --text-dim: #444; }

  html { scroll-behavior: auto; }

  body { background: #fff !important; color: #000 !important; font-size: 10pt; }

  .bg-decor, .site-header, .to-top, .hero-scroll, .hero-cta,
  .nav, .contact-form, .tooling-row, .skip-link { display: none !important; }

  .section { padding-block: 0.9rem; break-inside: avoid; }
  .section--alt { background: none !important; }

  .hero { min-height: auto; padding-top: 0; padding-bottom: 1rem; }
  .hero-name { -webkit-text-fill-color: #000; color: #000; }
  .grad-text { -webkit-text-fill-color: #000; color: #000; }

  /* Kill transitions as well as the animation, otherwise print can capture
     an element mid-fade and render it partially transparent. */
  [data-reveal] {
    opacity: 1 !important;
    transform: none !important;
    transition: none !important;
  }

  .card, .case, .tl-card, .edu-card, .cert-item {
    box-shadow: none !important;
    border: 1px solid #ccc !important;
    break-inside: avoid;
  }

  .tl-item, .case, .edu-card, .cert-item { break-inside: avoid; }

  a { text-decoration: none; color: #000; }
  .case-body { grid-template-columns: repeat(3, 1fr); }

  .site-footer { border-top: 1px solid #ccc; background: none; padding-block: 0.75rem; }
  .footer-copy, .footer-links a { color: #444; font-size: 8pt; }
}