@layer base {
  /* EQUATION */
  .equation-block {
    max-inline-size: 680px;
    padding: 3rem 2rem;
    margin: 2rem auto;
    text-align: center;
  }

  .equation {
    margin-block-end: 2rem;
    font-family: var(--display);
    font-size: clamp(1.4rem, 3.5vw, 2rem);
    font-weight: 600;
    line-height: 1.4;
    color: var(--gold);
  }

  .equation-terms {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
    gap: 1.5rem;
    text-align: left;
  }

  .equation-term {
    padding: 1rem;
    background: var(--bg-raised);
    border-radius: 6px;
  }

  .equation-term .term-name {
    margin-block-end: 0.4rem;
    font-family: var(--mono);
    font-size: 0.72rem;
    color: var(--cyan);
    text-transform: uppercase;
    letter-spacing: 0.1em;
  }

  .equation-term .term-desc {
    font-size: 0.88rem;
    line-height: 1.5;
    color: var(--text);
  }

  /* CROSSBAR */
  .crossbar-block {
    max-inline-size: 740px;
    padding: 3rem;
    margin: 3rem auto;
    text-align: center;
    background: linear-gradient(135deg, rgba(212, 168, 83, 0.04), rgba(155, 114, 207, 0.04));
    border: 1px solid rgba(212, 168, 83, 0.15);
    border-radius: 10px;
  }

  .crossbar-label {
    margin-block-end: 1rem;
    font-family: var(--mono);
    font-size: 0.62rem;
    color: var(--gold);
    text-transform: uppercase;
    letter-spacing: 0.22em;
  }

  .crossbar-endpoints {
    display: flex;
    flex-wrap: wrap;
    gap: 2rem;
    align-items: center;
    justify-content: center;
    margin-block-end: 2rem;
  }

  .crossbar-endpoint {
    min-inline-size: 200px;
    padding: 1.2rem 1.8rem;
    background: var(--bg);
    border-radius: 8px;
  }

  .crossbar-endpoint .ep-domain {
    margin-block-end: 0.3rem;
    font-family: var(--mono);
    font-size: 0.6rem;
    text-transform: uppercase;
    letter-spacing: 0.15em;
  }

  .crossbar-endpoint:first-child .ep-domain {
    color: var(--cyan);
  }
  .crossbar-endpoint:last-child .ep-domain {
    color: var(--violet);
  }

  .crossbar-endpoint .ep-name {
    font-family: var(--display);
    font-size: 1.1rem;
    font-weight: 600;
    color: var(--text-bright);
  }

  .crossbar-bridge {
    font-family: var(--display);
    font-size: 1.5rem;
    color: var(--gold-dim);
  }

  .crossbar-insight {
    max-inline-size: 560px;
    margin: 0 auto;
    font-family: var(--body);
    font-size: 1.05rem;
    line-height: 1.7;
    color: var(--text-bright);
  }

  /* PROTOCOL */
  .protocol {
    max-inline-size: 740px;
    padding: 3rem;
    margin: 3rem auto;
    background: var(--bg-raised);
    border-radius: 10px;
  }

  .protocol h3 {
    margin-block-end: 2rem;
    font-family: var(--display);
    font-size: 1.6rem;
    font-weight: 600;
    color: var(--text-bright);
    text-align: center;
  }

  .protocol-step {
    display: flex;
    gap: 1.5rem;
    align-items: flex-start;
    margin-block-end: 2rem;
  }

  .protocol-step:last-child {
    margin-block-end: 0;
  }

  .step-number {
    display: flex;
    flex-shrink: 0;
    align-items: center;
    justify-content: center;
    min-inline-size: 36px;
    block-size: 36px;
    margin-block-start: 0.2rem;
    font-family: var(--mono);
    font-size: 0.72rem;
    font-weight: 500;
    color: var(--gold);
    background: rgba(212, 168, 83, 0.1);
    border-radius: 50%;
  }

  .step-content h4 {
    margin-block-end: 0.4rem;
    font-family: var(--display);
    font-size: 1.05rem;
    font-weight: 600;
    color: var(--text-bright);
  }

  .step-content p {
    margin-block-end: 0;
    font-size: 0.92rem;
    line-height: 1.6;
  }

  /* VOID */
  .void-section {
    padding: 5rem 2rem;
    background: linear-gradient(180deg, var(--bg), rgba(107, 79, 143, 0.06), var(--bg));
  }

  /* REVEAL ANIMATION */
  .reveal {
    opacity: 0;
    transform: translateY(30px);
    transition:
      opacity 0.8s ease,
      transform 0.8s ease;
  }

  .reveal.visible {
    opacity: 1;
    transform: translateY(0);
  }

  /* EXPLORE BUTTON */
  .explore-btn {
    display: inline-flex;
    gap: 0.5rem;
    align-items: center;
    padding: 0.5rem 1.2rem;
    margin-block-start: 1.2rem;
    font-family: var(--mono);
    font-size: 0.68rem;
    color: var(--cyan);
    text-transform: uppercase;
    letter-spacing: 0.12em;
    cursor: pointer;
    background: rgba(78, 205, 196, 0.06);
    border: 1px solid rgba(78, 205, 196, 0.2);
    border-radius: 100px;
    transition:
      background 0.3s,
      border-color 0.3s,
      color 0.3s,
      box-shadow 0.3s;
  }
  .explore-btn:hover {
    background: rgba(78, 205, 196, 0.12);
    border-color: rgba(78, 205, 196, 0.4);
    box-shadow: 0 0 20px rgba(78, 205, 196, 0.1);
  }
  .crossbar-block .explore-btn {
    margin-block-start: 1.5rem;
  }
  .explore-btn svg {
    inline-size: 14px;
    block-size: 14px;
    fill: currentColor;
  }
  .explore-toast {
    position: fixed;
    inset-block-end: 2rem;
    inset-inline-start: 50%;
    z-index: 200;
    max-inline-size: 400px;
    padding: 1rem 1.8rem;
    text-align: center;
    pointer-events: none;
    background: var(--bg-raised);
    border: 1px solid rgba(78, 205, 196, 0.25);
    border-radius: 10px;
    opacity: 0;
    transform: translateX(-50%) translateY(20px);
    transition:
      opacity 0.4s ease,
      transform 0.4s ease;
  }
  .explore-toast.visible {
    pointer-events: all;
    opacity: 1;
    transform: translateX(-50%) translateY(0);
  }
  .explore-toast-title {
    margin-block-end: 0.4rem;
    font-family: var(--display);
    font-size: 1rem;
    font-weight: 600;
    color: var(--cyan);
  }
  .explore-toast-text {
    font-family: var(--body);
    font-size: 0.85rem;
    line-height: 1.5;
    color: var(--text);
  }

  /* NAV */
  nav {
    position: fixed;
    inset-block-start: 0;
    inset-inline-start: 0;
    inset-inline-end: 0;
    z-index: 100;
    padding: 1.2rem 2rem;
  }
}