/* =========================================================
   Block: § 02 / ARCHITECTURE  (.architecture)
   2-col grid: left editorial copy, right dark schematic.
   ========================================================= */
.architecture {
  background: #ffffff;
  padding: 120px 0;
}

.arch-grid {
  display: grid;
  grid-template-columns: 420px 1fr;
  gap: 96px;
  margin-top: 64px;
  align-items: start;
}

.arch-left .eyebrow { margin-bottom: 20px; }
.arch-left h3 {
  font-family: var(--font-serif);
  font-weight: 500;
  font-size: 36px;
  line-height: 1.15;
  letter-spacing: -.01em;
  margin: 0 0 20px;
}
.arch-left p {
  color: var(--ink-500);
  font-size: 16px;
  line-height: 1.6;
  margin: 0 0 14px;
}

.arch-positioning {
  margin: 0 0 20px;
  padding: 14px 20px;
  border-left: 2px solid var(--ink-900);
  font-family: var(--font-serif);
  font-style: italic;
  font-size: 19px;
  line-height: 1.45;
  color: var(--ink-900);
  max-width: 780px;
}

/* ---------- Dark schematic diagram ---------- */
.arch-diagram {
  background: var(--ink-950);
  color: var(--ink-0);
  border-radius: 2px;
  padding: 48px 48px 40px;
  position: relative;
  box-shadow: var(--shadow-lg);
}
.arch-diagram .ad-label {
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: .18em;
  color: var(--ink-300);
  text-transform: uppercase;
  margin-bottom: 32px;
}

.ad-flow {
  display: grid;
  grid-template-columns: 1fr 40px 1fr 40px 1fr;
  gap: 0;
  align-items: center;
}
.ad-col {
  display: flex;
  flex-direction: column;
  gap: 14px;
}
.ad-box {
  padding: 18px;
  background: var(--ink-800);
  border: 1px solid var(--ink-600);
  font-family: var(--font-mono);
  font-size: 11px;
}
.ad-box .nm {
  color: var(--ink-0);
  font-family: var(--font-sans);
  font-size: 14px;
  margin-bottom: 4px;
  font-weight: 500;
}
.ad-box .sb {
  color: var(--ink-400);
  font-size: 10px;
  letter-spacing: .1em;
  text-transform: uppercase;
}

.ad-center {
  border: 1px solid var(--cyan-400);
  background: linear-gradient(180deg, #0f1b2d 0%, #050a14 100%);
  padding: 32px 24px;
  text-align: center;
  box-shadow:
    0 0 0 1px rgba(56, 189, 248, .15),
    0 0 60px rgba(56, 189, 248, .1);
  position: relative;
}
.ad-center::before,
.ad-center::after {
  content: "";
  position: absolute;
  width: 8px;
  height: 8px;
  border: 1px solid var(--cyan-400);
  top: -4px;
}
.ad-center::before { left: -4px; }
.ad-center::after  { right: -4px; }
.ad-center .m {
  font-family: var(--font-serif);
  font-size: 28px;
  color: var(--ink-0);
  letter-spacing: -.02em;
  margin-bottom: 6px;
}
.ad-center .s {
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: .18em;
  color: var(--cyan-400);
  text-transform: uppercase;
}

.ad-arr {
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--ink-500);
  font-family: var(--font-mono);
  font-size: 10px;
  position: relative;
}
.ad-arr::after {
  content: "";
  position: absolute;
  left: 10%;
  right: 10%;
  top: 50%;
  border-top: 1px dashed var(--ink-500);
}
.ad-arr .bubble {
  position: relative;
  background: var(--ink-950);
  padding: 0 6px;
  z-index: 1;
  color: var(--cyan-400);
  letter-spacing: .1em;
  text-transform: uppercase;
}

/* Foot caps row */
.arch-caps {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 0;
  margin-top: 40px;
  padding-top: 32px;
  border-top: 1px solid var(--ink-700);
}
.arch-cap {
  padding: 0 16px;
  border-right: 1px solid var(--ink-700);
  color: var(--ink-300);
}
.arch-cap:last-child  { border-right: none; padding-right: 0; }
.arch-cap:first-child { padding-left: 0; }
.arch-cap .n {
  font-family: var(--font-serif);
  font-size: 24px;
  color: var(--ink-0);
  letter-spacing: -.01em;
  margin-bottom: 6px;
  white-space: nowrap;
}
.arch-cap .l {
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: .14em;
  color: var(--ink-400);
  text-transform: uppercase;
}

/* ---------- Responsive ---------- */
@media (max-width: 1100px) {
  .arch-grid {
    grid-template-columns: 1fr;
    gap: 48px;
  }
}

@media (max-width: 900px) {
  .arch-grid { display: block; }
  .arch-left,
  .arch-right { width: 100%; max-width: 100%; }

  .arch-diagram {
    padding: 24px;
    max-width: 100%;
    overflow: visible;
  }

  /* Mobile: vertical stack — sources -> Metrica -> targets.
     Dashed connector lines rotate from horizontal to vertical,
     with the "read" / "query" bubble centered on the line. */
  .ad-flow {
    display: flex;
    flex-direction: column;
    gap: 0;
    width: 100%;
    max-width: 100%;
    overflow: visible;
  }
  .ad-flow > * { flex-shrink: 1; width: 100%; }

  .ad-col {
    display: flex;
    flex-direction: column;
    gap: 10px;
  }

  .ad-arr {
    width: 100%;
    height: 44px;
    display: flex;
    align-items: center;
    justify-content: center;
  }
  .ad-arr::after {
    /* horizontal dashed line -> vertical */
    content: "";
    position: absolute;
    left: 50%;
    right: auto;
    top: 0;
    bottom: 0;
    width: 0;
    border-top: none;
    border-left: 1px dashed var(--ink-500);
    transform: translateX(-.5px);
  }
  .ad-arr .bubble {
    padding: 4px 8px;
  }

  .ad-center {
    width: 100%;
    padding: 20px 16px;
  }
  .ad-center .m { font-size: 24px; }

  .arch-caps {
    grid-template-columns: repeat(2, 1fr);
    gap: 16px 0;
  }
  .arch-cap {
    padding: 0 12px;
  }
  .arch-cap:nth-child(2n) {
    border-right: none;
    padding-right: 0;
  }
  .arch-cap:nth-child(2n+1) {
    padding-left: 0;
  }
}