@layer reset, tokens, base, layout, components, utilities;

@layer reset {
  *, *::before, *::after { box-sizing: border-box; }
  html { scroll-behavior: smooth; }
  body, h1, h2, h3, p, ul, ol, figure { margin: 0; }
  img, svg { display: block; max-inline-size: 100%; }
  button, input { font: inherit; }
}

@layer tokens {
  :root {
    color-scheme: light;
    --ink: oklch(0.975 0.004 95);
    --ink-raised: oklch(0.995 0.002 95);
    --ink-soft: oklch(0.945 0.006 95);
    --grid-line: oklch(0.45 0.008 95 / 0.08);
    --stage-surface: oklch(0.995 0.002 95 / 0.84);
    --chalk: oklch(0.235 0.008 80);
    --muted: oklch(0.47 0.01 95);
    --faint: oklch(0.55 0.008 95);
    --accent: oklch(0.4 0.085 165);
    --accent-soft: oklch(0.92 0.035 165);
    --blue: oklch(0.46 0.07 205);
    --yellow: var(--accent);
    --red: oklch(0.52 0.15 25);
    --green: oklch(0.43 0.09 155);
    --violet: oklch(0.5 0.08 305);
    --blue-soft: oklch(0.94 0.025 205);
    --red-soft: oklch(0.94 0.03 25);
    --green-soft: oklch(0.93 0.035 155);
    --violet-soft: oklch(0.94 0.025 305);
    --line: oklch(0.28 0.008 95 / 0.12);
    --line-strong: oklch(0.28 0.008 95 / 0.22);
    --display: "Palatino Linotype", "Iowan Old Style", Palatino, Georgia, serif;
    --body: "Segoe UI Variable Text", "Noto Sans SC", "Microsoft YaHei UI", sans-serif;
    --mono: "Cascadia Code", "SFMono-Regular", Consolas, monospace;
    --space-1: 0.375rem;
    --space-2: 0.75rem;
    --space-3: 1.125rem;
    --space-4: 1.5rem;
    --space-5: 2.25rem;
    --space-6: 3rem;
    --space-7: 4.5rem;
    --radius-sm: 0.45rem;
    --radius-md: 0.8rem;
    --radius-lg: 1.25rem;
    --page: min(100% - 2rem, 78rem);
  }
}

@layer base {
  html { background: var(--ink); }
  body {
    min-block-size: 100vh;
    background:
      linear-gradient(var(--grid-line) 1px, transparent 1px),
      linear-gradient(90deg, var(--grid-line) 1px, transparent 1px),
      radial-gradient(circle at 50% -10%, oklch(0.9 0.035 165 / 0.4), transparent 40rem),
      var(--ink);
    background-attachment: fixed;
    background-size: 2.4rem 2.4rem, 2.4rem 2.4rem, auto, auto;
    color: var(--chalk);
    font-family: var(--body);
    font-size: 1rem;
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
  }
  a {
    color: inherit;
    text-decoration-color: color-mix(in oklch, currentColor 45%, transparent);
    text-decoration-thickness: from-font;
    text-underline-position: from-font;
    text-underline-offset: 0.2em;
  }
  a:hover { text-decoration-color: currentColor; }
  button { color: inherit; }
  ::selection { background: var(--accent); color: var(--ink-raised); }
  :focus-visible {
    outline: 2px solid var(--accent);
    outline-offset: 3px;
  }
  h1, h2, h3 {
    font-family: var(--display);
    font-weight: 600;
    line-height: 1.08;
    white-space: nowrap;
  }
  h1 { font-size: clamp(2.65rem, 8vw, 6.8rem); letter-spacing: -0.055em; }
  h2 { font-size: clamp(1.25rem, 5vw, 3.8rem); letter-spacing: -0.04em; }
  h3 { font-size: clamp(1.3rem, 3vw, 1.8rem); letter-spacing: -0.025em; }
  code, .mono { font-family: var(--mono); font-variant-numeric: tabular-nums; }
}

@layer layout {
  .page-shell { inline-size: var(--page); margin-inline: auto; }
  .site-header {
    position: relative;
    z-index: 10;
    display: flex;
    align-items: center;
    justify-content: space-between;
    min-block-size: 4.75rem;
    padding-block: var(--space-2);
  }
  .brand {
    display: inline-flex;
    align-items: center;
    gap: var(--space-2);
    font-family: var(--mono);
    font-size: 0.8rem;
    letter-spacing: 0.08em;
    text-decoration: none;
    text-transform: uppercase;
  }
  .brand-mark {
    position: relative;
    inline-size: 1.9rem;
    block-size: 1.9rem;
    border: 1px solid var(--line-strong);
    border-radius: 50%;
  }
  .brand-mark::before, .brand-mark::after {
    content: "";
    position: absolute;
    inset: 50% auto auto 50%;
    background: var(--accent);
    transform: translate(-50%, -50%);
  }
  .brand-mark::before { inline-size: 0.72rem; block-size: 2px; }
  .brand-mark::after { inline-size: 2px; block-size: 0.72rem; }
  .site-nav { display: flex; align-items: center; gap: var(--space-3); }
  .site-nav a { color: var(--muted); font-size: 0.88rem; text-decoration: none; }
  .site-nav a:hover { color: var(--chalk); }
  .hero { padding-block: clamp(3rem, 8vw, 7.5rem) var(--space-6); }
  .hero-copy { max-inline-size: 63rem; }
  .hero-copy p { max-inline-size: 65ch; margin-block-start: var(--space-4); color: var(--muted); font-size: clamp(1.05rem, 2vw, 1.3rem); text-wrap: pretty; }
  .hero-actions { display: flex; flex-wrap: wrap; gap: var(--space-2); margin-block-start: var(--space-4); }
  .section { padding-block: var(--space-7); }
  .section-heading { display: grid; gap: var(--space-2); max-inline-size: 55rem; margin-block-end: var(--space-5); }
  .section-heading p { max-inline-size: 65ch; color: var(--muted); text-wrap: pretty; }
  .split { display: grid; grid-template-columns: minmax(0, 1.45fr) minmax(17rem, 0.55fr); gap: var(--space-4); align-items: start; }
  .narrative { display: grid; gap: var(--space-4); }
  .narrative p { max-inline-size: 65ch; color: var(--muted); text-wrap: pretty; }
  .site-footer { display: flex; justify-content: space-between; gap: var(--space-3); padding-block: var(--space-6); color: var(--faint); font-size: 0.82rem; }
}

@layer components {
  .skip-link {
    position: fixed;
    inset-block-start: var(--space-2);
    inset-inline-start: var(--space-2);
    z-index: 100;
    padding: 0.65rem 0.9rem;
    border-radius: var(--radius-sm);
    background: var(--chalk);
    color: var(--ink);
    transform: translateY(-180%);
  }
  .skip-link:focus { transform: translateY(0); }
  .eyebrow {
    display: inline-flex;
    align-items: center;
    gap: var(--space-2);
    color: var(--blue);
    font-family: var(--mono);
    font-size: 0.74rem;
    letter-spacing: 0.13em;
    text-transform: uppercase;
  }
  .eyebrow::before { content: ""; inline-size: 1.6rem; block-size: 1px; background: currentColor; }
  .accent-yellow { color: var(--yellow); }
  .accent-blue { color: var(--blue); }
  .accent-green { color: var(--green); }
  .accent-red { color: var(--red); }
  .button {
    display: inline-flex;
    min-block-size: 2.75rem;
    align-items: center;
    justify-content: center;
    gap: 0.55rem;
    padding-inline: 1rem;
    border: 1px solid var(--line-strong);
    border-radius: var(--radius-sm);
    background: var(--ink-soft);
    color: var(--chalk);
    font-family: var(--mono);
    font-size: 0.78rem;
    line-height: 1;
    text-decoration: none;
    cursor: pointer;
    transition-property: background-color, border-color, color, transform;
    transition-duration: 140ms;
    transition-timing-function: ease-out;
  }
  .button:hover { border-color: var(--line-strong); background: var(--ink-soft); }
  .button:active { transform: scale(0.96); }
  .button--primary { border-color: transparent; background: var(--accent); color: var(--ink-raised); font-weight: 700; }
  .button--primary:hover { background: oklch(0.35 0.085 165); }
  .button[aria-pressed="true"] { border-color: var(--blue); color: var(--blue); }
  .icon { inline-size: 1rem; block-size: 1rem; fill: none; stroke: currentColor; stroke-linecap: round; stroke-linejoin: round; stroke-width: 1.7; }
  .stage {
    position: relative;
    min-block-size: clamp(30rem, 66vw, 44rem);
    overflow: hidden;
    border: 1px solid var(--line);
    border-radius: var(--radius-lg);
    background:
      radial-gradient(circle at 50% 40%, oklch(0.91 0.025 165 / 0.56), transparent 68%),
      var(--stage-surface);
    box-shadow: 0 1.5rem 4rem oklch(0.25 0.01 95 / 0.08), inset 0 1px oklch(1 0 0 / 0.7);
  }
  .stage::after {
    content: "";
    position: absolute;
    inset: 0;
    pointer-events: none;
    background: linear-gradient(90deg, color-mix(in oklch, var(--ink-raised) 70%, transparent), transparent 8%, transparent 92%, color-mix(in oklch, var(--ink-raised) 70%, transparent));
  }
  .stage-topbar {
    position: relative;
    z-index: 4;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: var(--space-2);
    min-block-size: 3.5rem;
    padding-inline: var(--space-3);
    border-block-end: 1px solid var(--line);
    background: oklch(0.985 0.003 95 / 0.9);
    backdrop-filter: blur(12px);
  }
  .stage-label { color: var(--muted); font-family: var(--mono); font-size: 0.72rem; letter-spacing: 0.08em; text-transform: uppercase; }
  .stage-status { display: inline-flex; align-items: center; gap: 0.55rem; color: var(--chalk); font-family: var(--mono); font-size: 0.75rem; }
  .status-dot { inline-size: 0.48rem; block-size: 0.48rem; border-radius: 50%; background: var(--blue); box-shadow: 0 0 0.8rem currentColor; color: var(--blue); }
  .stage-canvas { position: relative; z-index: 2; min-block-size: clamp(22rem, 52vw, 34rem); padding: clamp(1rem, 3vw, 2rem); }
  .stage-controls {
    position: relative;
    z-index: 4;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: var(--space-2);
    min-block-size: 4.8rem;
    padding: var(--space-2) var(--space-3);
    border-block-start: 1px solid var(--line);
    background: oklch(0.985 0.003 95 / 0.94);
    backdrop-filter: blur(12px);
  }
  .control-group { display: flex; flex-wrap: wrap; align-items: center; gap: 0.5rem; }
  .control-button { min-inline-size: 2.75rem; padding-inline: 0.75rem; }
  .range-wrap { display: grid; gap: 0.3rem; color: var(--muted); font-family: var(--mono); font-size: 0.7rem; }
  .range-wrap > span { white-space: nowrap; }
  input[type="range"] { accent-color: var(--accent); inline-size: min(12rem, 35vw); }
  .legend { display: flex; flex-wrap: wrap; gap: var(--space-3); color: var(--muted); font-family: var(--mono); font-size: 0.7rem; }
  .legend span { display: inline-flex; align-items: center; gap: 0.45rem; }
  .legend i { inline-size: 0.55rem; block-size: 0.55rem; border-radius: 50%; background: var(--legend-color); box-shadow: 0 0 0.6rem color-mix(in oklch, var(--legend-color) 60%, transparent); }
  .metric-grid { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: var(--space-2); }
  .metric {
    min-block-size: 7rem;
    padding: var(--space-3);
    border-radius: var(--radius-md);
    background: var(--ink-raised);
    box-shadow: inset 0 0 0 1px var(--line);
  }
  .metric-label { color: var(--muted); font-family: var(--mono); font-size: 0.7rem; letter-spacing: 0.08em; text-transform: uppercase; }
  .metric-value { margin-block-start: 0.4rem; color: var(--yellow); font-family: var(--display); font-size: clamp(1.75rem, 4vw, 2.7rem); line-height: 1; font-variant-numeric: tabular-nums; }
  .metric-note { margin-block-start: 0.4rem; color: var(--faint); font-size: 0.76rem; }
  .formula {
    padding: var(--space-3);
    border-radius: var(--radius-md);
    background: var(--ink-raised);
    color: var(--chalk);
    font-family: var(--display);
    font-size: clamp(1.08rem, 2vw, 1.55rem);
    text-align: center;
    overflow-wrap: anywhere;
    text-wrap: balance;
    box-shadow: inset 0 0 0 1px var(--line);
  }
  .callout { padding-inline-start: var(--space-3); border-inline-start: 2px solid var(--blue); }
  .callout strong { display: block; margin-block-end: 0.35rem; color: var(--chalk); font-family: var(--mono); font-size: 0.8rem; }
  .source-link { display: inline-flex; align-items: center; gap: 0.5rem; color: var(--blue); font-family: var(--mono); font-size: 0.78rem; }
  .atlas { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: var(--space-3); }
  .atlas-card {
    position: relative;
    display: grid;
    min-block-size: 12rem;
    align-content: space-between;
    gap: var(--space-4);
    overflow: hidden;
    padding: var(--space-4);
    border-radius: var(--radius-lg);
    background: var(--ink-raised);
    color: inherit;
    text-decoration: none;
    box-shadow: inset 0 0 0 1px var(--line);
    transition-property: transform, background-color, box-shadow;
    transition-duration: 200ms;
    transition-timing-function: ease-out;
  }
  .atlas-card:hover { transform: translateY(-0.25rem); background: var(--ink-soft); box-shadow: inset 0 0 0 1px var(--line-strong), 0 1rem 3rem oklch(0 0 0 / 0.18); }
  .atlas-card:active { transform: scale(0.96); }
  .atlas-index { color: var(--card-color, var(--blue)); font-family: var(--mono); font-size: 0.72rem; letter-spacing: 0.08em; }
  .atlas-card p { max-inline-size: 45ch; color: var(--muted); font-size: 0.92rem; text-wrap: pretty; }
  .atlas-meta { display: flex; justify-content: space-between; gap: var(--space-2); color: var(--faint); font-family: var(--mono); font-size: 0.68rem; }
  .agent-row { display: flex; flex-wrap: wrap; justify-content: center; gap: clamp(0.55rem, 2vw, 1rem); }
  .agent {
    display: grid;
    inline-size: clamp(4.5rem, 12vw, 7rem);
    aspect-ratio: 1;
    place-items: center;
    border: 1px solid var(--line-strong);
    border-radius: 50%;
    background: var(--ink-soft);
    color: var(--muted);
    font-family: var(--mono);
    font-size: clamp(0.72rem, 2vw, 0.9rem);
    transition-property: border-color, color, background-color, transform, opacity, box-shadow;
    transition-duration: 320ms;
    transition-timing-function: ease-out;
  }
  .agent[data-state="thinking"] { border-color: var(--accent); color: var(--accent); background: var(--accent-soft); box-shadow: 0 0 1.8rem oklch(0.4 0.085 165 / 0.12); }
  .agent[data-state="conflict"] { border-color: var(--red); color: var(--red); background: var(--red-soft); transform: translateY(0.35rem); }
  .agent[data-state="ready"] { border-color: var(--blue); color: var(--blue); }
  .agent[data-state="committed"] { border-color: var(--green); color: var(--green); background: var(--green-soft); }
  .agent small { display: block; color: currentColor; font-size: 0.62rem; opacity: 0.72; }
  .message-lane { display: grid; gap: var(--space-2); margin-block-start: var(--space-4); }
  .message {
    display: grid;
    grid-template-columns: 4.8rem minmax(0, 1fr) auto;
    align-items: center;
    gap: var(--space-2);
    min-block-size: 3.35rem;
    padding: 0.7rem 0.9rem;
    border-radius: var(--radius-sm);
    background: oklch(0.995 0.002 95 / 0.88);
    color: var(--muted);
    font-family: var(--mono);
    font-size: 0.72rem;
    box-shadow: inset 0 0 0 1px var(--line);
    transition-property: color, background-color, transform, opacity, box-shadow;
    transition-duration: 280ms;
    transition-timing-function: ease-out;
  }
  .message[data-state="held"] { color: var(--red); background: var(--red-soft); transform: translateX(0.5rem); }
  .message[data-state="commit"] { color: var(--green); background: var(--green-soft); }
  .message strong { color: var(--chalk); font-weight: 600; }
  .pill { display: inline-flex; align-items: center; min-block-size: 1.65rem; padding-inline: 0.55rem; border-radius: 99rem; background: var(--ink-soft); color: currentColor; font-family: var(--mono); font-size: 0.65rem; white-space: nowrap; box-shadow: inset 0 0 0 1px currentColor; }
  .phase-rail { display: grid; grid-template-columns: repeat(var(--phase-count, 4), minmax(0, 1fr)); gap: 0.35rem; margin-block-start: var(--space-4); }
  .phase { display: grid; gap: 0.35rem; color: var(--faint); font-family: var(--mono); font-size: 0.64rem; }
  .phase::before { content: ""; block-size: 2px; background: var(--line-strong); }
  .phase[data-state="active"] { color: var(--yellow); }
  .phase[data-state="active"]::before { background: var(--accent); box-shadow: 0 0 0.65rem color-mix(in oklch, var(--accent) 35%, transparent); }
  .phase[data-state="done"] { color: var(--green); }
  .phase[data-state="done"]::before { background: var(--green); }
  .code-panel { padding: var(--space-3); border-radius: var(--radius-md); background: var(--ink-soft); font-family: var(--mono); font-size: 0.76rem; line-height: 1.8; box-shadow: inset 0 0 0 1px var(--line); overflow-x: auto; }
  .code-line { display: block; color: var(--muted); white-space: pre; }
  .code-line[data-state="active"] { color: var(--yellow); }
  .code-key { color: var(--violet); }
  .code-value { color: var(--green); }
  .sr-only { position: absolute; inline-size: 1px; block-size: 1px; padding: 0; margin: -1px; overflow: hidden; clip: rect(0, 0, 0, 0); white-space: nowrap; border: 0; }
}

@layer utilities {
  .muted { color: var(--muted); }
  .faint { color: var(--faint); }
  .center { text-align: center; }
  .stack { display: grid; gap: var(--space-3); }
  .spacer-top { margin-block-start: var(--space-4); }
  .nowrap { white-space: nowrap; }
}

@media (max-width: 58rem) {
  :root { --page: min(100% - 1.25rem, 78rem); }
  .split { grid-template-columns: 1fr; }
  .stage { min-block-size: 34rem; }
  .atlas { grid-template-columns: 1fr; }
  .narrative { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}

@media (max-width: 40rem) {
  .site-nav a:not(:last-child) { display: none; }
  .hero { padding-block-start: var(--space-5); }
  .hero.algorithm-hero h1 { max-inline-size: none; font-size: clamp(1.25rem, 7vw, 3rem); }
  .stage-controls { align-items: flex-start; flex-direction: column; }
  .progress-group { inline-size: 100%; }
  .narrative { grid-template-columns: 1fr; }
  .metric-grid { grid-template-columns: 1fr 1fr; }
  .message { grid-template-columns: 3.5rem minmax(0, 1fr); }
  .message .pill { grid-column: 2; justify-self: start; }
  .site-footer { flex-direction: column; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { animation-duration: 0.01ms !important; animation-iteration-count: 1 !important; transition-duration: 0.01ms !important; }
}

@media (forced-colors: active) {
  :focus-visible { outline-color: Highlight; }
  .status-dot, .legend i { box-shadow: none; }
}