.se-hero {
    max-width: var(--max);
    margin: 0 auto;
    padding: clamp(80px, 14vh, 160px) var(--pad-x) clamp(40px, 6vh, 80px);
  }
  .se-hero-grid {
    display: grid;
    grid-template-columns: 1.3fr 1fr;
    gap: 60px;
    align-items: end;
  }
  @media (max-width: 980px) { .se-hero-grid { grid-template-columns: 1fr; gap: 32px; } }
  .se-hero h1 {
    font-family: var(--font-display);
    font-size: clamp(56px, 9vw, 132px);
    line-height: 0.92;
    letter-spacing: -0.035em;
    font-weight: 400;
    margin: 26px 0 0;
  }
  .se-hero h1 .y { color: var(--qai); }
  .se-hero h1 .r { color: var(--quaxis); }
  .se-hero h1 .v { color: var(--qbit); }
  .se-hero h1 .dim { color: var(--fg-4); }
  .se-hero .lead {
    color: var(--fg-2);
    margin: 0;
    padding-bottom: 14px;
    max-width: 46ch;
  }

  .se-body {
    max-width: var(--max);
    margin: 0 auto;
    padding: clamp(40px, 8vh, 80px) var(--pad-x) clamp(80px, 12vh, 140px);
    display: grid;
    grid-template-columns: 1fr 440px;
    gap: 80px;
    align-items: start;
  }
  @media (max-width: 1100px) { .se-body { grid-template-columns: 1fr; gap: 40px; } }

  .se-sections { display: grid; gap: 0; }
  .sec {
    --c: var(--fg);
    padding: 72px 0;
    border-top: 1px solid var(--line);
  }
  .sec:first-child { border-top: 0; padding-top: 12px; }
  .sec.y { --c: var(--qai); }
  .sec.r { --c: var(--quaxis); }
  .sec.v { --c: var(--qbit); }
  .sec .ix {
    font-family: var(--font-mono);
    font-size: 11px;
    letter-spacing: 0.22em;
    text-transform: uppercase;
    color: var(--c);
    display: inline-flex;
    align-items: center;
    gap: 12px;
    margin-bottom: 18px;
  }
  .sec .ix::before {
    content: "";
    width: 8px; height: 8px;
    border-radius: 50%;
    background: var(--c);
    box-shadow: 0 0 12px var(--c);
  }
  .sec h2 {
    font-family: var(--font-display);
    font-size: clamp(34px, 4.2vw, 54px);
    line-height: 1.02;
    letter-spacing: -0.025em;
    font-weight: 400;
    margin: 0 0 22px;
    max-width: 20ch;
  }
  .sec h2 .accent { color: var(--c); }
  .sec p {
    font-size: 17px;
    line-height: 1.6;
    color: var(--fg-2);
    margin: 0 0 16px;
    max-width: 60ch;
  }
  .sec p strong { color: var(--fg); font-weight: 500; }
  .sec p .k { color: var(--c); font-weight: 500; }

  .sec-list {
    list-style: none;
    padding: 0;
    margin: 24px 0 0;
    display: grid;
    gap: 10px;
  }
  .sec-list li {
    display: grid;
    grid-template-columns: auto 1fr;
    gap: 14px;
    padding: 14px 18px;
    border: 1px solid var(--line);
    border-radius: 12px;
    background: var(--bg-1);
    font-size: 15px;
    line-height: 1.5;
    color: var(--fg-2);
  }
  .sec-list li .tag {
    font-family: var(--font-mono);
    font-size: 10px;
    letter-spacing: 0.18em;
    color: var(--c);
    align-self: start;
    padding-top: 2px;
    white-space: nowrap;
  }

  .chips {
    display: flex;
    gap: 8px;
    flex-wrap: wrap;
    margin-top: 22px;
  }
  .chip {
    font-family: var(--font-mono);
    font-size: 11px;
    letter-spacing: 0.12em;
    text-transform: uppercase;
    padding: 8px 14px;
    border-radius: 999px;
    border: 1px solid var(--line);
    color: var(--fg-2);
  }
  .chip.k { color: var(--c); border-color: color-mix(in oklab, var(--c) 40%, var(--line)); }

  .dna-aside {
    position: sticky;
    top: 100px;
    align-self: start;
  }
  @media (max-width: 1100px) {
    .dna-aside { position: static; width: 100%; max-width: 440px; margin: 0 auto; }
  }
  .dna-frame {
    position: relative;
    width: 100%;
    aspect-ratio: 440 / 720;
    background: linear-gradient(180deg, var(--bg-2) 0%, var(--bg-1) 100%);
    border: 1px solid var(--line);
    border-radius: 22px;
    overflow: hidden;
  }
  .dna-frame::before {
    content: "";
    position: absolute;
    inset: 0;
    background-image:
      linear-gradient(rgba(255,255,255,0.03) 1px, transparent 1px),
      linear-gradient(90deg, rgba(255,255,255,0.03) 1px, transparent 1px);
    background-size: 28px 28px;
    pointer-events: none;
  }
  .dna-head {
    position: absolute;
    top: 18px;
    left: 18px;
    right: 18px;
    display: flex;
    justify-content: space-between;
    font-family: var(--font-mono);
    font-size: 10px;
    letter-spacing: 0.2em;
    text-transform: uppercase;
    color: var(--fg-4);
    z-index: 3;
  }
  .dna-head .pulse {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    color: var(--fg-3);
  }
  .dna-head .pulse::before {
    content: "";
    width: 6px; height: 6px;
    border-radius: 50%;
    background: var(--fg-3);
    animation: pulse-dot 2.4s ease-in-out infinite;
  }
  @keyframes pulse-dot {
    0%, 100% { opacity: 0.35; transform: scale(1); }
    50% { opacity: 1; transform: scale(1.4); }
  }
  .dna-svg {
    position: absolute;
    inset: 0;
    width: 100%;
    height: 100%;
  }
  .dna-foot {
    position: absolute;
    bottom: 16px;
    left: 18px;
    right: 18px;
    font-family: var(--font-mono);
    font-size: 10px;
    letter-spacing: 0.18em;
    text-transform: uppercase;
    color: var(--fg-4);
    display: flex;
    justify-content: space-between;
    z-index: 3;
  }
  .dna-foot .active-label {
    color: var(--fg);
    transition: color .4s ease;
  }
  .dna-foot .active-label.y { color: var(--qai); }
  .dna-foot .active-label.r { color: var(--quaxis); }
  .dna-foot .active-label.v { color: var(--qbit); }

  .strand {
    fill: none;
    stroke-width: 1.6;
    stroke-linecap: round;
  }
  .strand.bg {
    stroke: rgba(255,255,255,0.18);
    stroke-dasharray: 2 4;
  }
  .strand.fg {
    stroke: rgba(255,255,255,0.7);
  }
  .rung-line {
    stroke: rgba(255,255,255,0.12);
    stroke-width: 1;
    transition: stroke .6s ease, stroke-width .6s ease;
  }
  .rung-dot {
    fill: var(--bg-1);
    stroke: rgba(255,255,255,0.4);
    stroke-width: 1.4;
    transition:
      fill .6s ease,
      stroke .6s ease,
      r .6s cubic-bezier(.2,.7,.2,1);
  }
  .rung-label {
    font-family: var(--font-mono);
    font-size: 9px;
    letter-spacing: 0.18em;
    text-transform: uppercase;
    fill: var(--fg-4);
    transition: fill .6s ease, opacity .6s ease;
  }
  .rung-label-active {
    font-size: 10px;
    fill: var(--fg);
    opacity: 0;
    transition: opacity .6s ease;
  }

  .rung[data-active="true"] .rung-line { stroke: var(--rc); stroke-width: 2.2; }
  .rung[data-active="true"] .rung-dot  { fill: var(--rc); stroke: var(--rc); filter: drop-shadow(0 0 8px var(--rc)); }
  .rung[data-active="true"] .rung-label-active { opacity: 1; fill: var(--rc); }
  .rung[data-active="true"] .rung-label { opacity: 0; }

  .halo {
    fill: none;
    stroke: var(--rc, transparent);
    stroke-width: 1;
    opacity: 0;
    transition: opacity .8s ease;
  }
  .rung[data-active="true"] .halo { opacity: 0.7; animation: halo-pulse 3s ease-in-out infinite; }
  @keyframes halo-pulse {
    0%, 100% { opacity: 0.4; transform: scale(1); }
    50% { opacity: 0.85; transform: scale(1.15); }
  }

  @keyframes strand-flow {
    to { stroke-dashoffset: -36; }
  }
  .strand.bg { animation: strand-flow 6s linear infinite; }

  .se-close {
    max-width: var(--max);
    margin: 0 auto;
    padding: clamp(60px, 10vh, 120px) var(--pad-x);
    border-top: 1px solid var(--line);
    text-align: center;
  }
  .se-close h2 {
    font-family: var(--font-display);
    font-size: clamp(40px, 6vw, 78px);
    line-height: 1.0;
    letter-spacing: -0.03em;
    font-weight: 400;
    margin: 0 auto 24px;
    max-width: 18ch;
  }
  .se-close h2 em {
    font-style: normal;
    background: linear-gradient(90deg, var(--qai), var(--quaxis), var(--qbit));
    -webkit-background-clip: text;
    background-clip: text;
    color: transparent;
  }
  .se-close .lead {
    color: var(--fg-2);
    max-width: 56ch;
    margin: 0 auto 32px;
  }

  @media (max-width: 640px) {
    .se-hero h1 { font-size: clamp(38px, 10vw, 52px); }
    .se-close h2 { max-width: none; font-size: clamp(32px, 8vw, 48px); }
    .se-close .lead { max-width: none; }
    .sec h2 { max-width: none; font-size: clamp(28px, 7vw, 40px); }
    .sec p { font-size: 15px; }
    .dna-aside { max-width: 100%; }
  }