/* ==========================================================================
   Arsen Vaneev — portfolio
   Built from the Claude Design "Nocturne" handoff. Tokens below are the
   prototype's overrides of the Nocturne base; sizes/radii come from Nocturne.
   ========================================================================== */

:root {
  --font-body: "Inter", system-ui, sans-serif;
  --font-heading: "Inter", system-ui, sans-serif;
  --font-display: "Michroma", "Inter", system-ui, sans-serif;
  --font-mono: ui-monospace, "SFMono-Regular", Menlo, Consolas, monospace;

  --color-bg: #0d0d10;
  --color-surface: #17171b;
  --color-text: #eae8e3;
  --color-accent: #d95f57;
  --color-divider: color-mix(in srgb, #eae8e3 15%, transparent);

  --shadow-sm: 0 0 0 1px #2a2a30;

  --radius-md: 8px;

  /* Derived text tints, so the same value isn't respelled at every use site. */
  --ink-88: color-mix(in srgb, var(--color-text) 88%, transparent);
  --ink-82: color-mix(in srgb, var(--color-text) 82%, transparent);
  --ink-70: color-mix(in srgb, var(--color-text) 70%, transparent);
  --ink-60: color-mix(in srgb, var(--color-text) 60%, transparent);
  --ink-55: color-mix(in srgb, var(--color-text) 55%, transparent);
  --ink-50: color-mix(in srgb, var(--color-text) 50%, transparent);
  --ink-30: color-mix(in srgb, var(--color-text) 30%, transparent);
  --ink-26: color-mix(in srgb, var(--color-text) 26%, transparent);

  --chrome-bg: color-mix(in srgb, var(--color-bg) 82%, transparent);
}

:root[data-theme="light"] {
  --color-bg: #f4f3f0;
  --color-surface: #e9e7e2;
  --color-text: #17171b;
  --color-accent: #a32a22;
  --color-divider: color-mix(in srgb, #17171b 16%, transparent);
  --shadow-sm: 0 0 0 1px #d6d3cc;
}

/* — base — */

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

html { scroll-behavior: smooth; }

body {
  margin: 0;
  font-family: var(--font-body);
  font-size: 15px;
  line-height: 1.55;
  font-weight: 400;
  background: var(--color-bg);
  color: var(--color-text);
  -webkit-font-smoothing: antialiased;
}

h1, h2, h3, h4 {
  font-family: var(--font-heading);
  font-weight: 500;
  line-height: 1.12;
  letter-spacing: -0.015em;
  margin: 0 0 5.6px;
}

p { margin: 0 0 8.4px; }

a { color: var(--color-accent); text-underline-offset: 3px; }

:focus { outline: none; }
:focus-visible { outline: 2px solid var(--color-accent); outline-offset: 2px; }
::selection { background: color-mix(in srgb, var(--color-accent) 30%, transparent); }

.icon { width: 1em; height: 1em; display: block; flex: none; fill: currentColor; }

.page {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

main {
  flex: 1;
  width: min(100%, 940px);
  margin: 0 auto;
  padding-inline: clamp(20px, 5vw, 32px);
  padding-bottom: clamp(40px, 6vw, 72px);
  display: flex;
  flex-direction: column;
  text-align: center;
}

/* — theme toggle (fixed) — */

.theme-toggle {
  position: fixed;
  left: clamp(14px, 3vw, 24px);
  bottom: clamp(14px, 3vw, 24px);
  z-index: 30;
  display: inline-flex;
  align-items: center;
  gap: 5px;
  background: var(--chrome-bg);
  backdrop-filter: blur(8px);
  border: 1px solid var(--color-divider);
  border-radius: var(--radius-md);
  color: var(--ink-70);
  font-family: var(--font-mono);
  font-size: 10.5px;
  letter-spacing: 0.08em;
  padding: 8px;
  cursor: pointer;
}
.theme-toggle:hover { border-color: var(--color-accent); color: var(--color-accent); }
.theme-toggle .icon { font-size: 13px; }
.theme-toggle-label { display: none; }

/* — section rail (fixed, docks in on scroll) — */

.rail {
  position: fixed;
  z-index: 25;
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 8px;
  transition: transform 460ms cubic-bezier(.2, .8, .2, 1), opacity 300ms ease;
  opacity: 0;
  pointer-events: none;
}
body.is-docked .rail { opacity: 1; pointer-events: auto; }

.rail a {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  text-decoration: none;
  color: var(--color-text);
  border: 1px solid var(--color-divider);
  border-radius: var(--radius-md);
  padding: 9px 12px;
  background: var(--chrome-bg);
  backdrop-filter: blur(8px);
  transition: border-color 200ms ease, color 200ms ease, box-shadow 200ms ease;
}
.rail a:hover { border-color: var(--color-accent); color: var(--color-accent); }
.rail a .icon { font-size: 14px; }
.rail-label { display: none; }

.rail a.is-active {
  border-color: var(--color-accent);
  color: var(--color-accent);
  box-shadow: inset 0 0 0 100px color-mix(in srgb, var(--color-accent) 14%, transparent);
}

/* The AI entry is accent-lined at rest, so it reads as the odd one out. */
.rail a.accent,
.hero-nav a.accent {
  color: var(--color-accent);
  border-color: color-mix(in srgb, var(--color-accent) 55%, transparent);
}
.rail a.accent:hover { background: color-mix(in srgb, var(--color-accent) 14%, transparent); }
.rail a.accent.is-active {
  border-color: var(--color-accent);
  box-shadow: inset 0 0 0 100px color-mix(in srgb, var(--color-accent) 18%, transparent);
}

/* — hero — */

.hero {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  /* Optical centering: true center reads as slightly low, so the bottom padding
     pulls the centered stack up by half its value without breaking the centering. */
  padding-bottom: clamp(48px, 10vh, 104px);
}

.mark {
  display: inline-flex;
  align-items: center;
  color: var(--color-accent);
  margin: 0 0 20px;
}

.hero h1 {
  width: fit-content;
  margin: 0 auto 14px;
  font-size: clamp(38px, 7vw, 62px);
  line-height: 1.02;
  letter-spacing: -0.03em;
}

.hero h1 span {
  display: inline-block;
  animation: nameGlitch 7.3s infinite both;
}

.tagline {
  font-size: clamp(14px, 2.1vw, 21px);
  line-height: 1.45;
  margin: 0 auto 28px;
  color: var(--ink-88);
  white-space: nowrap;
}

/* The tagline is deliberately one line, but below ~420px its 14px floor makes
   it wider than the viewport and the whole page scrolls sideways. Let it keep
   shrinking down there instead. */
@media (max-width: 420px) {
  .tagline { font-size: 3.5vw; }
}

.hero-nav {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 12px;
  transition: opacity 260ms ease, transform 380ms cubic-bezier(.2, .8, .2, 1);
}
body.is-docked .hero-nav {
  opacity: 0;
  transform: translateY(-10px);
  pointer-events: none;
}

.hero-nav a {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  text-decoration: none;
  color: var(--color-text);
  border: 1px solid var(--color-divider);
  border-radius: var(--radius-md);
  padding: 11px 18px;
  min-height: 44px;
}
.hero-nav a:hover { border-color: var(--color-accent); color: var(--color-accent); }
.hero-nav a.accent:hover { background: color-mix(in srgb, var(--color-accent) 12%, transparent); }
.hero-nav a .icon { font-size: 15px; }

/* — sections — */

section[id] {
  padding-top: clamp(48px, 7vw, 88px);
  scroll-margin-top: 64px;
}

.sec-head {
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  align-items: center;
  gap: 14px;
  margin-bottom: 22px;
}

.sec-head h2 {
  font-family: var(--font-display);
  font-weight: 400;
  font-size: clamp(14px, 2.1vw, 20px);
  letter-spacing: 0.1em;
  text-transform: uppercase;
  margin: 0;
  white-space: nowrap;
}

.sec-head-left {
  display: flex;
  align-items: center;
  justify-content: flex-end;
  gap: 12px;
  min-width: 0;
}

.sec-num {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.12em;
  color: var(--color-accent);
}

/* Decorative binary flanking the title, clipped and faded at the outer end. */
.bin {
  overflow: hidden;
  white-space: nowrap;
  font-family: var(--font-mono);
  font-size: 9.5px;
  line-height: 1;
  letter-spacing: 0.38em;
  color: var(--ink-30);
  user-select: none;
}
.bin-l {
  flex: 1;
  max-width: 160px;
  text-align: right;
  -webkit-mask-image: linear-gradient(to right, transparent, #000 78%);
  mask-image: linear-gradient(to right, transparent, #000 78%);
}
.bin-r {
  justify-self: start;
  width: 100%;
  max-width: 160px;
  text-align: left;
  -webkit-mask-image: linear-gradient(to left, transparent, #000 78%);
  mask-image: linear-gradient(to left, transparent, #000 78%);
}

/* Short rule between sub-blocks — deliberately inside the section rules. */
.subrule {
  height: 1px;
  width: min(46%, 300px);
  margin: 0 auto;
  background: var(--ink-26);
  border: 0;
}
.subrule-spaced { margin-top: 26px; }

/* — projects — */

.projects {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(min(100%, 265px), 1fr));
  gap: 22px;
}

.project {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 10px;
}

.project h3 { font-size: 19px; margin: 4px 0 0; }

.stack {
  font-family: var(--font-mono);
  font-size: 11.5px;
  line-height: 1.6;
  margin: 0;
  color: var(--ink-60);
}

.project p:not(.stack) {
  font-size: 14px;
  line-height: 1.55;
  margin: 0;
  color: var(--ink-82);
  text-wrap: pretty;
}

.project-links {
  display: flex;
  gap: 14px;
  flex-wrap: wrap;
  justify-content: center;
  margin-top: 2px;
}
.project-links a {
  font-family: var(--font-mono);
  font-size: 11.5px;
  color: var(--color-accent);
  text-decoration: none;
  border-bottom: 1px solid color-mix(in srgb, var(--color-accent) 40%, transparent);
}
.project-links a:hover { border-bottom-color: var(--color-accent); }

/* Architecture-diagram placeholder — awaiting a real export. */
.diagram {
  width: 100%;
  border: 1px solid var(--color-divider);
  border-radius: var(--radius-md);
  overflow: hidden;
  background: var(--color-surface);
}
.diagram-slot {
  position: relative;
  width: 100%;
  height: clamp(112px, 13vw, 148px);
  background: rgba(127, 127, 127, .08);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 6px;
  padding: 12px;
  font-size: 13px;
  line-height: 1.3;
  font-weight: 500;
  letter-spacing: .01em;
  color: inherit;
  opacity: .75;
}
.diagram-slot svg { opacity: .45; }
.diagram-slot::after {
  content: "";
  position: absolute;
  inset: 0;
  border: 1.5px dashed currentColor;
  opacity: .35;
  pointer-events: none;
}

/* — experience — */

.roles {
  display: flex;
  flex-direction: column;
  width: min(100%, 700px);
  margin: 0 auto;
}

.role { padding: 18px 0; }

.role .meta {
  font-family: var(--font-mono);
  font-size: 11.5px;
  margin: 0 0 6px;
  color: var(--ink-55);
}

.role h3 { font-size: 17px; margin: 0 0 2px; }

.role p:not(.meta) {
  font-size: 14px;
  line-height: 1.55;
  margin: 0 auto;
  max-width: 62ch;
  color: var(--ink-82);
  text-wrap: pretty;
}

.footnote {
  font-family: var(--font-mono);
  font-size: 11.5px;
  line-height: 1.9;
  color: var(--ink-55);
  margin: 16px 0 0;
}

/* — about — */

.about-lede {
  font-size: 16px;
  line-height: 1.65;
  margin: 0 auto 26px;
  max-width: 64ch;
  text-wrap: pretty;
}

.about-cols {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(min(100%, 210px), 1fr));
  gap: 20px 26px;
  padding-top: 22px;
  width: min(100%, 820px);
  margin: 0 auto;
}

.about-cols h3 {
  font-family: var(--font-mono);
  font-weight: 400;
  font-size: 10px;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--color-accent);
  margin: 0 0 5px;
}

.about-cols p {
  font-size: 14px;
  line-height: 1.55;
  margin: 0;
  color: var(--ink-82);
}

.contact {
  display: flex;
  gap: 20px;
  flex-wrap: wrap;
  justify-content: center;
  padding-top: 20px;
}
.contact a {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--color-accent);
  text-decoration: none;
  border-bottom: 1px solid color-mix(in srgb, var(--color-accent) 35%, transparent);
}
.contact a:hover { border-bottom-color: var(--color-accent); }
.contact .icon { font-size: 14px; }

/* — AI Arsen (under construction) — */

.ai-card {
  position: relative;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 14px;
  padding: clamp(18px, 3vw, 26px);
  width: min(100%, 660px);
  margin: 0 auto;
  border: 1px dashed var(--color-divider);
  border-radius: var(--radius-md);
  background: color-mix(in srgb, var(--color-surface) 60%, transparent);
  box-shadow: var(--shadow-sm);
}

/* Straddles the card's top edge; the halo cuts the dashed border behind it. */
.badge {
  position: absolute;
  top: 0;
  right: 16px;
  transform: translateY(-50%);
  display: inline-flex;
  align-items: center;
  gap: 5px;
  padding: 4px 9px;
  border: 1px solid color-mix(in srgb, var(--color-accent) 60%, transparent);
  border-radius: 999px;
  background: var(--color-bg);
  box-shadow: 0 0 0 3px var(--color-bg);
  font-family: var(--font-mono);
  font-size: 8.5px;
  line-height: 1;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--color-accent);
}
.badge::before {
  content: "";
  width: 4px;
  height: 4px;
  border-radius: 50%;
  background: var(--color-accent);
}

.ai-row {
  display: flex;
  gap: 10px;
  flex-wrap: wrap;
  align-items: center;
  justify-content: center;
  width: 100%;
}

.ai-row input {
  flex: 1 1 240px;
  min-height: 36px;
  padding: 6px 10px;
  font-family: var(--font-mono);
  font-size: 13px;
  text-align: center;
  color: var(--color-text);
  background: var(--color-surface);
  border: 1px solid var(--color-divider);
  border-radius: var(--radius-md);
}
.ai-row input:disabled { opacity: 0.45; cursor: not-allowed; }

.ai-row button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  font: inherit;
  font-size: 14px;
  line-height: 1.2;
  color: var(--color-accent);
  background: transparent;
  border: 1px solid var(--color-accent);
  border-radius: var(--radius-md);
  padding: 5.6px 10px;
  cursor: pointer;
}
.ai-row button:disabled { opacity: 0.45; cursor: not-allowed; }
.ai-row button .icon { font-size: 15px; }

.ai-note {
  font-family: var(--font-mono);
  font-size: 11px;
  line-height: 1.9;
  color: var(--ink-50);
  margin: 0;
}

/* — the name glitch — */

@keyframes nameGlitch {
  0%, 3.1% { transform: none; text-shadow: none; clip-path: none; opacity: 1; }
  3.2% { transform: translate(-9px, 2px) skewX(-9deg); text-shadow: 8px 0 var(--color-accent), -7px 0 var(--ink-70); clip-path: inset(12% 0 46% 0); }
  3.8% { transform: translate(11px, -3px); text-shadow: -10px 0 var(--color-accent), 5px 2px var(--ink-55); clip-path: inset(52% 0 8% 0); }
  4.3% { transform: translate(-5px, 3px) skewX(6deg); text-shadow: 6px -2px var(--color-accent); clip-path: none; opacity: 0.72; }
  4.9%, 14.7% { transform: none; text-shadow: none; clip-path: none; opacity: 1; }
  14.8% { transform: translate(7px, 1px); text-shadow: -9px 0 var(--color-accent); clip-path: inset(30% 0 30% 0); }
  15.3% { transform: translate(-8px, -2px) skewX(-7deg); text-shadow: 7px 1px var(--color-accent); clip-path: none; }
  15.8%, 28.4% { transform: none; text-shadow: none; clip-path: none; opacity: 1; }
  28.5% { transform: translate(4px, -4px) skewX(11deg); text-shadow: -12px 0 var(--color-accent), 6px 0 var(--ink-50); clip-path: inset(0 0 62% 0); }
  29% { transform: translate(-12px, 2px); text-shadow: 9px 0 var(--color-accent); clip-path: inset(64% 0 0 0); }
  29.4% { transform: translate(3px, 0); text-shadow: -4px 0 var(--color-accent); clip-path: none; opacity: 0.55; }
  30%, 44.1% { transform: none; text-shadow: none; clip-path: none; opacity: 1; }
  44.2% { transform: translate(-6px, -3px) skewX(-12deg); text-shadow: 11px 0 var(--color-accent); clip-path: inset(20% 0 40% 0); }
  44.9% { transform: translate(9px, 3px); text-shadow: -8px -1px var(--color-accent); clip-path: none; }
  45.5%, 57.3% { transform: none; text-shadow: none; clip-path: none; opacity: 1; }
  57.4% { transform: translate(-10px, 1px) skewX(8deg); text-shadow: 7px 2px var(--color-accent), -6px 0 var(--ink-60); clip-path: inset(44% 0 22% 0); }
  58% { transform: translate(5px, -2px); text-shadow: -11px 0 var(--color-accent); clip-path: none; opacity: 0.66; }
  58.6%, 71.8% { transform: none; text-shadow: none; clip-path: none; opacity: 1; }
  71.9% { transform: translate(12px, 2px) skewX(-10deg); text-shadow: -7px 0 var(--color-accent); clip-path: inset(8% 0 58% 0); }
  72.4% { transform: translate(-7px, -3px); text-shadow: 10px 1px var(--color-accent); clip-path: inset(60% 0 4% 0); }
  73%, 86.2% { transform: none; text-shadow: none; clip-path: none; opacity: 1; }
  86.3% { transform: translate(-4px, 4px) skewX(13deg); text-shadow: 12px 0 var(--color-accent); clip-path: none; opacity: 0.6; }
  86.9% { transform: translate(8px, -1px); text-shadow: -9px -2px var(--color-accent); clip-path: inset(36% 0 26% 0); }
  87.5%, 95.6% { transform: none; text-shadow: none; clip-path: none; opacity: 1; }
  95.7% { transform: translate(-11px, 0) skewX(-6deg); text-shadow: 6px 0 var(--color-accent); clip-path: inset(24% 0 48% 0); }
  96.3%, 100% { transform: none; text-shadow: none; clip-path: none; opacity: 1; }
}

/* ==========================================================================
   Responsive modes. The rail is a left gutter rail on wide and mid screens
   and a bottom bar on phones, where no gutter exists.
   ========================================================================== */

/* Phones — rail becomes a bottom bar, toggle moves to the top to clear it. */
@media (max-width: 699.98px) {
  .rail {
    flex-direction: row;
    align-items: center;
    inset: auto 0 0 0;
    padding: 10px clamp(12px, 4vw, 20px) 14px;
    background: linear-gradient(to top, var(--color-bg) 62%, transparent);
    transform: translateY(130%);
  }
  body.is-docked .rail { transform: translateY(0%); }

  .theme-toggle { top: 12px; bottom: auto; }
}

/* Tablet and up — rail docks into the left gutter, sliding in from the edge. */
@media (min-width: 700px) {
  .rail {
    flex-direction: column;
    align-items: flex-start;
    top: 50%;
    left: 10px;
    padding: 0;
    background: transparent;
    transform: translateY(-50%) translateX(-130%);
  }
  body.is-docked .rail { transform: translateY(-50%) translateX(0%); }
}

/* Mid widths have no real gutter, so the rail goes icon-only and main
   reserves a 62px hole for it. */
@media (min-width: 700px) and (max-width: 1219.98px) {
  main { padding-inline: 62px; }
}

/* Wide — real gutters, so labels return on both the rail and the toggle. */
@media (min-width: 1220px) {
  .rail { left: clamp(12px, 2.5vw, 26px); }
  .rail-label { display: inline; }
  .theme-toggle-label { display: inline; }
  .theme-toggle { padding: 7px 10px; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  .hero h1 span { animation: none; }
  .rail, .hero-nav { transition: none; }
}