/* ===== 人列 2D 演示网页 · styles.css ===== */

:root {
  --ink-950: #11110f;
  --ink-900: #191813;
  --ink-800: #27231b;
  --gold-500: #b79a61;
  --gold-300: #d1b77d;
  --paper-100: #dfcfaa;
  --paper-200: #cfb98e;
  --paper-ink: #2b241b;
  --cinnabar: #7d3429;
  --cinnabar-hover: #984438;
  --signal-0: #23211c;
  --signal-1: #f1e7cf;
  --line-dark: rgba(44, 35, 23, 0.58);

  --font-serif: "Noto Serif SC", "Songti SC", "SimSun", serif;
  --font-mono: "IBM Plex Mono", "Consolas", monospace;
  --font-sans: "Noto Sans SC", "Microsoft YaHei", sans-serif;

  --maxw: 1440px;
  --radius: 3px;
}

/* ===== Reset ===== */
*, *::before, *::after { box-sizing: border-box; }
html { scroll-behavior: smooth; -webkit-text-size-adjust: 100%; }
body {
  margin: 0;
  font-family: var(--font-sans);
  background: var(--ink-950);
  color: var(--paper-100);
  line-height: 1.6;
  overflow-x: hidden;
}
img { display: block; max-width: 100%; }
button { font-family: inherit; cursor: pointer; }
a { color: inherit; }

/* ===== 通用按钮 ===== */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 44px;
  padding: 0 20px;
  border: 1px solid var(--gold-500);
  border-radius: var(--radius);
  font-family: var(--font-serif);
  font-size: 1rem;
  letter-spacing: 0.04em;
  text-decoration: none;
  transition: background .18s, color .18s, box-shadow .18s, transform .08s;
  background: transparent;
  color: var(--paper-100);
}
.btn:active { transform: translateY(1px); }
.btn:focus-visible { outline: 2px solid var(--gold-300); outline-offset: 2px; }
.btn-cinnabar {
  background: var(--cinnabar);
  border-color: var(--cinnabar);
  color: var(--paper-100);
}
.btn-cinnabar:hover { background: var(--cinnabar-hover); border-color: var(--cinnabar-hover); }
.btn-gold {
  background: var(--gold-500);
  border-color: var(--gold-500);
  color: var(--ink-950);
  font-weight: 600;
}
.btn-gold:hover { background: var(--gold-300); border-color: var(--gold-300); }
.btn-ghost {
  background: transparent;
  color: var(--gold-300);
}
.btn-ghost:hover { background: rgba(183,154,97,.12); color: var(--paper-100); }
.btn:disabled { opacity: .42; cursor: not-allowed; }

/* ===== 顶部导航 ===== */
.topnav {
  position: sticky;
  top: 0;
  z-index: 100;
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 64px;
  padding: 0 clamp(16px, 4vw, 48px);
  background: rgba(17,17,15,.92);
  backdrop-filter: blur(6px);
  border-bottom: 1px solid rgba(183,154,97,.4);
}
.topnav-brand {
  display: flex;
  align-items: center;
  gap: 10px;
  text-decoration: none;
}
.brand-seal {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 38px; height: 38px;
  background: var(--ink-800);
  border: 1px solid var(--gold-500);
  border-radius: 2px;
  font-family: var(--font-serif);
  font-size: 1.2rem;
  color: var(--gold-300);
}
.brand-text {
  font-family: var(--font-serif);
  font-size: 1.25rem;
  color: var(--paper-100);
  display: flex;
  flex-direction: column;
  line-height: 1.1;
}
.brand-sub {
  font-family: var(--font-mono);
  font-size: .6rem;
  letter-spacing: .18em;
  color: var(--gold-500);
}
.topnav-links {
  display: flex;
  gap: 28px;
}
.topnav-links a {
  font-family: var(--font-serif);
  font-size: 1.05rem;
  color: var(--paper-100);
  text-decoration: none;
  padding: 8px 2px;
  border-bottom: 1px solid transparent;
  transition: border-color .18s, color .18s;
}
.topnav-links a:hover { color: var(--gold-300); border-bottom-color: var(--gold-500); }

/* ===== Hero ===== */
.hero {
  position: relative;
  min-height: 760px;
  display: flex;
  flex-direction: column;
  justify-content: center;
  background-color: var(--ink-950);
  overflow: hidden;
}
.hero-overlay {
  position: absolute;
  inset: 0;
  pointer-events: none;
  /* 上下暗角 */
  background: radial-gradient(120% 90% at 30% 50%, transparent 50%, rgba(8,8,7,.45) 100%);
}
.hero-content {
  position: relative;
  z-index: 2;
  padding: 0 clamp(16px, 8vw, 96px);
  max-width: 640px;
  margin-left: 4%;
}
.hero-eyebrow {
  font-family: var(--font-mono);
  font-size: .82rem;
  letter-spacing: .12em;
  color: var(--gold-300);
  margin: 0 0 12px;
  text-transform: uppercase;
}
.hero-title {
  font-family: var(--font-serif);
  font-size: clamp(3.5rem, 10vw, 6.5rem);
  margin: 0;
  line-height: 1;
  color: var(--paper-100);
  letter-spacing: .12em;
  text-shadow: 0 2px 12px rgba(0,0,0,.6);
}
.hero-subtitle {
  font-family: var(--font-serif);
  font-size: clamp(1.1rem, 3vw, 1.6rem);
  margin: 14px 0 0;
  color: var(--gold-300);
  letter-spacing: .14em;
}
.hero-desc {
  font-size: 1.05rem;
  color: var(--paper-100);
  margin: 26px 0 0;
  max-width: 30em;
  text-shadow: 0 1px 8px rgba(0,0,0,.7);
}
.hero-actions {
  display: flex;
  gap: 14px;
  margin-top: 32px;
  flex-wrap: wrap;
}
.scale-promise {
  border: 1px solid rgba(209,183,125,.55);
  background: linear-gradient(135deg, rgba(17,17,15,.84), rgba(39,35,27,.68));
  box-shadow: inset 0 0 0 1px rgba(17,17,15,.55), 0 10px 28px rgba(0,0,0,.22);
}
.scale-promise-hero {
  display: grid;
  grid-template-columns: auto 1fr;
  gap: 2px 16px;
  align-items: center;
  max-width: 520px;
  margin-top: 24px;
  padding: 12px 16px;
  border-left: 3px solid var(--cinnabar);
}
.scale-kicker {
  grid-column: 1 / -1;
  font-family: var(--font-mono);
  font-size: .7rem;
  color: var(--gold-500);
  letter-spacing: .08em;
}
.scale-multiplier {
  font-family: var(--font-mono);
  font-size: clamp(1.05rem, 2.4vw, 1.35rem);
  color: var(--gold-300);
  white-space: nowrap;
}
.scale-copy {
  font-size: .82rem;
  color: rgba(241,231,207,.82);
  line-height: 1.45;
}
.future-pills {
  grid-column: 1 / -1;
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  margin-top: 7px;
}
.future-pills span {
  padding: 3px 8px;
  border: 1px solid rgba(183,154,97,.38);
  background: rgba(125,52,41,.22);
  font: .66rem var(--font-mono);
  color: var(--gold-300);
}
.hero-hint {
  position: absolute;
  bottom: 24px;
  left: 50%;
  transform: translateX(-50%);
  z-index: 2;
  font-family: var(--font-mono);
  font-size: .8rem;
  color: var(--gold-300);
  letter-spacing: .08em;
  white-space: nowrap;
  opacity: .85;
}
.hint-arrow {
  display: inline-block;
  animation: bobArrow 2s ease-in-out infinite;
}
@keyframes bobArrow { 0%,100% { transform: translateY(0);} 50% { transform: translateY(4px);} }

/* ===== 通用 section ===== */
.section {
  max-width: var(--maxw);
  margin: 0 auto;
  padding: clamp(56px, 8vw, 110px) clamp(16px, 5vw, 64px);
}
.section-head {
  margin-bottom: 40px;
}
.section-index {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: .85rem;
  color: var(--gold-500);
  letter-spacing: .2em;
  margin-bottom: 8px;
}
.section-head h2 {
  font-family: var(--font-serif);
  font-size: clamp(1.8rem, 4vw, 2.6rem);
  margin: 0 0 10px;
  color: var(--paper-100);
  letter-spacing: .04em;
}
.section-lead {
  font-size: 1.08rem;
  color: var(--gold-300);
  margin: 0;
  max-width: 40em;
}

/* ===== 原理卡片 ===== */
.principle-cards {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}
.paper-card {
  position: relative;
  background: var(--paper-100);
  color: var(--paper-ink);
  border: 1px solid var(--gold-500);
  border-radius: var(--radius);
  padding: 28px 24px 24px;
  box-shadow: 0 4px 0 rgba(17,14,10,.5), 0 10px 24px rgba(0,0,0,.35);
}
.paper-card h3 {
  font-family: var(--font-serif);
  font-size: 1.4rem;
  margin: 12px 0 8px;
  color: var(--paper-ink);
}
.paper-card p {
  margin: 0 0 10px;
  color: rgba(43,36,27,.86);
}
.card-stamp {
  display: inline-block;
  font-family: var(--font-serif);
  font-size: .72rem;
  letter-spacing: .16em;
  color: var(--paper-100);
  background: var(--cinnabar);
  padding: 3px 10px;
  border-radius: 2px;
}
.card-note {
  display: block;
  font-family: var(--font-mono);
  font-size: .78rem;
  color: var(--cinnabar);
  border-top: 1px dashed var(--line-dark);
  padding-top: 10px;
  margin-top: 14px;
}
.card-soldier, .card-drum {
  display: flex;
  align-items: flex-end;
  height: 100px;
  margin-bottom: 4px;
}

/* ===== 教程区 ===== */
.tutorial-grid {
  display: grid;
  grid-template-columns: 0.85fr 1.6fr 0.75fr;
  gap: 22px;
  align-items: start;
}
.tut-legend { padding-top: 24px; }
.legend-list {
  list-style: none;
  padding: 0;
  margin: 14px 0;
  display: flex;
  flex-direction: column;
  gap: 10px;
  font-family: var(--font-mono);
  font-size: .95rem;
  color: var(--paper-ink);
}
.legend-list li { display: flex; align-items: center; gap: 10px; }
.flag {
  width: 22px; height: 28px;
  border: 1px solid var(--paper-ink);
  border-radius: 1px;
  flex-shrink: 0;
  position: relative;
}
.flag::before {
  content: "";
  position: absolute;
  left: 3px; top: 3px; bottom: 3px;
  width: 2px;
  background: var(--paper-ink);
}
.flag-0 { background: var(--signal-0); }
.flag-1 { background: var(--signal-1); }
.legend-rule, .legend-tip {
  font-size: .92rem;
  color: rgba(43,36,27,.8);
  margin: 8px 0 0;
}
.legend-rule { color: var(--cinnabar); font-family: var(--font-serif); }

/* 与门舞台 */
.gate-stage {
  padding: 24px 20px 22px;
}
.gate-stage h3 {
  font-family: var(--font-serif);
  font-size: 1.3rem;
  margin: 12px 0 18px;
  color: var(--paper-ink);
  text-align: center;
  letter-spacing: .12em;
}
.gate-arena {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 10px;
  min-height: 220px;
}
.gate-top {
  display: grid;
  grid-template-columns: 1fr 1.1fr 1fr;
  align-items: center;
  gap: 8px;
  width: 100%;
}
.gate-input, .gate-output {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 8px;
}
.gate-stage.stale .gate-output {
  opacity: .38;
  filter: grayscale(.35);
}
.gate-stage.stale .gate-saying { color: var(--cinnabar); }
.gate-label {
  font-family: var(--font-mono);
  font-size: .8rem;
  color: var(--paper-ink);
  letter-spacing: .08em;
}
.gate-soldier {
  display: block;
  width: 120px;
  height: 137px;
  position: relative;
}
.gate-mid {
  position: relative;
  height: 160px;
  display: flex;
  align-items: center;
  justify-content: center;
}
.gate-lines {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
}
.wire {
  stroke: var(--paper-ink);
  stroke-width: 1.5;
  stroke-dasharray: 5 4;
  opacity: .55;
  transition: stroke .25s, opacity .25s, stroke-dashoffset .6s;
}
.wire.active {
  stroke: var(--gold-500);
  opacity: 1;
  stroke-width: 2.2;
  animation: wireFlow .8s linear infinite;
}
@keyframes wireFlow { to { stroke-dashoffset: -18; } }
.gate-badge {
  position: relative;
  z-index: 2;
  display: flex;
  align-items: center;
  justify-content: center;
  width: 64px; height: 64px;
  background: var(--ink-900);
  border: 1.5px solid var(--gold-500);
  border-radius: 2px;
  box-shadow: 0 0 0 4px var(--paper-100), 0 4px 10px rgba(0,0,0,.3);
  transition: box-shadow .3s, transform .3s;
}
.gate-and {
  font-family: var(--font-mono);
  font-size: .82rem;
  color: var(--gold-300);
  letter-spacing: .04em;
  font-weight: 600;
}
.gate-badge.active {
  box-shadow: 0 0 0 4px var(--paper-100), 0 0 16px 4px rgba(183,154,97,.6);
  transform: scale(1.06);
}

.flag-toggle {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 6px;
  background: none;
  border: none;
  padding: 4px;
}
.flag-toggle:focus-visible { outline: 2px solid var(--cinnabar); outline-offset: 4px; border-radius: 2px; }
.bit-tag {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 30px; height: 30px;
  font-family: var(--font-mono);
  font-size: 1.05rem;
  font-weight: 600;
  border-radius: 2px;
  border: 1px solid var(--paper-ink);
}
.bit-0 { background: var(--signal-0); color: var(--paper-100); }
.bit-1 { background: var(--signal-1); color: var(--paper-ink); }

.gate-controls {
  display: flex;
  gap: 12px;
  justify-content: center;
  margin-top: 18px;
}
.gate-saying {
  font-family: var(--font-serif);
  font-size: .95rem;
  color: var(--cinnabar);
  text-align: center;
  margin: 14px 0 0;
  min-height: 1.4em;
}

/* 真值表 */
.truth-card {
  background: var(--ink-900);
  border: 1px solid var(--gold-500);
  border-radius: var(--radius);
  padding: 24px 18px;
}
.truth-card h3 {
  font-family: var(--font-serif);
  font-size: 1.15rem;
  margin: 12px 0 14px;
  color: var(--gold-300);
  text-align: center;
  letter-spacing: .12em;
}
.truth-table {
  width: 100%;
  border-collapse: collapse;
  font-family: var(--font-mono);
  font-size: 1.05rem;
}
.truth-table th, .truth-table td {
  text-align: center;
  padding: 9px 6px;
  border-bottom: 1px solid rgba(183,154,97,.25);
}
.truth-table th {
  color: var(--gold-500);
  font-weight: 600;
  letter-spacing: .08em;
  font-size: .9rem;
}
.truth-table td { color: var(--paper-100); }
.truth-table tr.truth-hl td { color: var(--gold-300); font-weight: 600; }
.truth-table tr.truth-hl td:last-child { color: var(--gold-300); }
.truth-table tbody tr:last-child { border-bottom: none; }

/* ===== Demo 演算场 ===== */
.demo-console {
  border: 1.5px solid var(--gold-500);
  border-radius: var(--radius);
  background: var(--ink-900);
  box-shadow: 0 8px 0 rgba(17,14,10,.5), 0 20px 48px rgba(0,0,0,.4);
  overflow: hidden;
  position: relative;
}
/* 四角角花 */
.demo-console::before, .demo-console::after {
  content: "";
  position: absolute;
  width: 18px; height: 18px;
  border: 1.5px solid var(--gold-300);
  pointer-events: none;
}
.demo-console::before { top: 6px; left: 6px; border-right: none; border-bottom: none; }
.demo-console::after { bottom: 6px; right: 6px; border-left: none; border-top: none; }

.demo-topbar {
  display: grid;
  grid-template-columns: minmax(150px, 1fr) auto 36px;
  align-items: center;
  gap: 16px;
  height: 56px;
  padding: 0 20px;
  border-bottom: 1px solid rgba(183,154,97,.3);
  background: var(--ink-950);
}
.demo-mode-label {
  font-family: var(--font-serif);
  font-size: 1.05rem;
  color: var(--gold-300);
  letter-spacing: .08em;
  min-width: 0;
}
.op-tabs {
  display: flex;
  gap: 6px;
}
.op-tab {
  min-height: 36px;
  padding: 0 18px;
  background: transparent;
  border: 1px solid var(--gold-500);
  border-radius: 2px;
  color: var(--gold-300);
  font-family: var(--font-mono);
  font-size: .92rem;
  letter-spacing: .06em;
  transition: background .15s, color .15s;
}
.op-tab.active { background: var(--gold-500); color: var(--ink-950); font-weight: 600; }
.op-tab:focus-visible { outline: 2px solid var(--gold-300); outline-offset: 2px; }
.op-tab:disabled { opacity: .4; cursor: not-allowed; }
.demo-help {
  width: 36px; height: 36px;
  border: 1px solid var(--gold-500);
  border-radius: 50%;
  background: transparent;
  color: var(--gold-300);
  font-family: var(--font-mono);
  font-size: 1rem;
}
.demo-help:hover { background: rgba(183,154,97,.15); }

.demo-phasebar {
  display: grid;
  grid-template-columns: 1fr auto 1fr auto 1fr;
  align-items: center;
  gap: 10px;
  min-height: 58px;
  padding: 8px 20px;
  border-bottom: 1px solid rgba(183,154,97,.28);
  background: #15140f;
}
.phase-step {
  display: grid;
  grid-template-columns: 28px auto;
  grid-template-rows: auto auto;
  align-items: center;
  column-gap: 8px;
  padding: 5px 8px;
  border: 1px solid rgba(183,154,97,.22);
  color: rgba(223,207,170,.5);
  transition: color .2s, border-color .2s, background .2s, box-shadow .2s;
}
.phase-step b {
  grid-row: 1 / 3;
  display: grid;
  place-items: center;
  width: 28px;
  height: 28px;
  border: 1px solid currentColor;
  border-radius: 50%;
  font-family: var(--font-mono);
}
.phase-step > span { font-family: var(--font-serif); font-size: .92rem; line-height: 1.1; }
.phase-step small { font-family: var(--font-mono); font-size: .62rem; line-height: 1.1; }
.phase-step.active {
  color: var(--paper-100);
  border-color: var(--gold-300);
  background: rgba(125,52,41,.42);
  box-shadow: 0 0 14px rgba(183,154,97,.3);
}
.phase-step.done { color: var(--gold-300); border-color: rgba(183,154,97,.45); }
.phase-arrow { color: rgba(183,154,97,.45); font-family: var(--font-mono); }

.demo-body {
  display: grid;
  grid-template-columns: 74% 26%;
  min-height: 460px;
}

/* 俯视演算场 */
.formation {
  position: relative;
  padding: 18px 16px;
  overflow: hidden;
  border-right: 1px solid rgba(183,154,97,.25);
}
.formation-cols {
  position: relative;
  z-index: 2;
  display: flex;
  flex-direction: column;
  gap: 10px;
  height: 100%;
}
/* 远景静态阵列 */
.formation-bg-array {
  position: absolute;
  inset: 0;
  z-index: 1;
  opacity: .14;
  background-image:
    radial-gradient(circle at 10% 12%, var(--gold-500) 1px, transparent 2px),
    radial-gradient(circle at 30% 80%, var(--gold-500) 1px, transparent 2px);
  pointer-events: none;
}

/* 单条 bit 通道 */
.bit-lane {
  display: grid;
  grid-template-columns: 124px minmax(28px, 1fr) 72px minmax(28px, 1fr) 64px;
  align-items: center;
  gap: 6px;
  padding: 6px 6px;
  border-bottom: 1px dashed rgba(183,154,97,.18);
  min-height: 120px;
}
.lane-label {
  font-family: var(--font-mono);
  font-size: .72rem;
  color: var(--gold-500);
  text-align: center;
  letter-spacing: .04em;
}
.lane-soldier {
  position: relative;
  width: 64px;
  height: 73px; /* 保持 420:480 比例 */
  display: flex;
  align-items: flex-end;
  justify-content: center;
}
.lane-soldier .soldier-asset { width: 100%; height: 100%; }
.lane-bit {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 26px; height: 26px;
  font-family: var(--font-mono);
  font-size: .92rem;
  font-weight: 600;
  border-radius: 2px;
  border: 1px solid var(--gold-500);
  position: absolute;
  bottom: -15px;
  right: 50%;
  transform: translateX(50%);
  z-index: 3;
}
.lane-bit.bit-0 { background: var(--signal-0); color: var(--paper-100); border-color: var(--signal-0); }
.lane-bit.bit-1 { background: var(--signal-1); color: var(--ink-950); }

/* 通道连线 */
.lane-wire {
  position: relative;
  min-width: 0;
}
.lane-wire:not(.lane-wire-input) {
  height: 2px;
  background: repeating-linear-gradient(90deg, var(--paper-ink) 0 5px, transparent 5px 9px);
  opacity: .5;
}
.lane-wire .pulse {
  position: absolute;
  top: -3px;
  width: 16px; height: 8px;
  border-radius: 4px;
  opacity: 0;
  transition: opacity .25s;
}
.lane-wire:not(.lane-wire-input).active { opacity: 1; background: repeating-linear-gradient(90deg, var(--gold-500) 0 6px, transparent 6px 11px); animation: wireFlowH .7s linear infinite; }
@keyframes wireFlowH { to { background-position-x: 17px; } }
.lane-wire.active .pulse { opacity: 1; }
.pulse-0 { background: var(--cinnabar); }
.pulse-1 { background: var(--signal-1); box-shadow: 0 0 6px var(--gold-300); }
.lane-wire-input {
  display: grid;
  gap: 13px;
}
.signal-track {
  position: relative;
  display: block;
  height: 2px;
  background: repeating-linear-gradient(90deg, var(--paper-ink) 0 5px, transparent 5px 9px);
  opacity: .5;
}
.lane-wire-input.active .signal-track {
  opacity: 1;
  background: repeating-linear-gradient(90deg, var(--gold-500) 0 6px, transparent 6px 11px);
  animation: wireFlowH .7s linear infinite;
}
.signal-track::before {
  content: attr(data-label);
  position: absolute;
  right: calc(100% + 3px);
  top: -8px;
  font: .55rem var(--font-mono);
  color: var(--gold-500);
}

/* 中间门阵 */
.lane-gate {
  display: flex;
  align-items: center;
  justify-content: center;
  position: relative;
}
.gate-box {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 56px; height: 44px;
  background: var(--ink-800);
  border: 1px solid var(--gold-500);
  border-radius: 2px;
  font-family: var(--font-mono);
  font-size: .7rem;
  color: var(--gold-300);
  transition: box-shadow .3s, transform .3s, border-color .3s;
}
.gate-box.active {
  border-color: var(--gold-300);
  box-shadow: 0 0 14px 2px rgba(183,154,97,.55);
  transform: scale(1.05);
}

/* B 兵在 A 兵下方（桌面用并排，移动端切换） */
.lane-b-wrap { display: flex; align-items: center; justify-content: center; }

/* 输入兵区：A 在上 B 在下 */
.lane-inputs {
  display: grid;
  grid-template-columns: 1fr 1fr;
  align-items: center;
  gap: 2px;
  justify-content: center;
}
.lane-inputs .lane-label {
  grid-column: 1 / -1;
  font-size: .6rem;
  margin-bottom: 1px;
}
.lane-inputs .input-soldier .lane-soldier {
  width: 48px;
  height: 55px;
}
.lane-inputs .input-soldier .lane-bit {
  width: 18px;
  height: 18px;
  font-size: .68rem;
  bottom: -13px;
  right: 50%;
}

/* 可点击输入兵 */
.input-soldier {
  background: none;
  border: none;
  padding: 0;
  position: relative;
  display: flex;
  flex-direction: column;
  align-items: flex-end;
  justify-content: center;
}
.input-name, .output-name {
  font-family: var(--font-mono);
  font-size: .58rem;
  color: var(--gold-500);
  line-height: 1;
}
.input-name { align-self: center; margin-bottom: 2px; }
.output-name { position: absolute; top: -11px; left: 50%; transform: translateX(-50%); }
.input-soldier:focus-visible { outline: 2px solid var(--gold-300); outline-offset: 3px; border-radius: 2px; }
.input-soldier:hover .lane-soldier { filter: brightness(1.12); }
.input-soldier:disabled { cursor: not-allowed; opacity: .7; }

/* 信息面板 */
.info-panel {
  padding: 18px 18px;
  display: flex;
  flex-direction: column;
  gap: 14px;
  background: var(--ink-950);
}
.info-block {
  display: flex;
  flex-direction: column;
  gap: 4px;
  padding-bottom: 12px;
  border-bottom: 1px solid rgba(183,154,97,.18);
}
.info-label {
  font-family: var(--font-mono);
  font-size: .72rem;
  color: var(--gold-500);
  letter-spacing: .12em;
  text-transform: uppercase;
}
.info-value {
  font-family: var(--font-serif);
  font-size: 1.08rem;
  color: var(--paper-100);
}
.info-value.mono { font-family: var(--font-mono); font-size: 1.15rem; letter-spacing: .08em; color: var(--gold-300); }
.info-dec { font-size: .85rem; color: var(--gold-500); margin-left: 6px; }
.info-out .info-value { color: var(--gold-300); font-size: 1.3rem; }
.info-status { border-bottom: none; padding-bottom: 0; }
.info-status .info-value { font-size: .95rem; color: var(--paper-100); }
.info-help { font-size: .82rem; color: var(--gold-300); margin: 0; }

/* 输出变暗标记 */
.info-block.stale .info-value { opacity: .35; }
.info-block.stale::after {
  content: "等待号令";
  font-family: var(--font-mono);
  font-size: .7rem;
  color: var(--cinnabar);
}

/* 底部控制栏 */
.demo-controls {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
  padding: 14px 20px;
  border-top: 1px solid rgba(183,154,97,.3);
  background: var(--ink-950);
  flex-wrap: wrap;
}
.ctrl-buttons {
  display: flex;
  gap: 10px;
  flex-wrap: wrap;
}
.ctrl-buttons .btn { min-height: 40px; padding: 0 16px; font-size: .95rem; }

.timeline {
  display: flex;
  align-items: center;
  gap: 12px;
  flex: 1;
  min-width: 200px;
  max-width: 460px;
}
.tl-end {
  font-family: var(--font-mono);
  font-size: .78rem;
  color: var(--gold-500);
  white-space: nowrap;
}
.tl-track {
  position: relative;
  flex: 1;
  height: 4px;
  background: rgba(183,154,97,.22);
  border-radius: 2px;
}
.tl-fill {
  position: absolute;
  left: 0; top: 0; bottom: 0;
  width: 0%;
  background: var(--gold-500);
  border-radius: 2px;
  transition: width .4s ease;
}
.tl-dot {
  position: absolute;
  top: 50%;
  left: 0%;
  transform: translate(-50%, -50%);
  width: 12px; height: 12px;
  background: var(--gold-300);
  border: 1px solid var(--ink-950);
  border-radius: 50%;
  transition: left .4s ease;
}
.tl-tick {
  position: absolute;
  top: 10px;
  transform: translateX(-50%);
  font-family: var(--font-mono);
  font-size: .7rem;
  color: var(--gold-500);
}
.tl-tick[data-t="1"] { left: 33.33%; }
.tl-tick[data-t="2"] { left: 66.66%; }
.tl-tick[data-t="3"] { left: 100%; }

/* ===== 十以内四位加法器 ===== */
.adder {
  max-width: none;
  padding-left: clamp(16px, 5vw, 64px);
  padding-right: clamp(16px, 5vw, 64px);
  background:
    radial-gradient(circle at 78% 18%, rgba(125,52,41,.13), transparent 32%),
    linear-gradient(180deg, #15140f, var(--ink-950));
}
.adder > .section-head, .adder-lab { max-width: var(--maxw); margin-inline: auto; }
.adder-lab {
  display: grid;
  grid-template-columns: minmax(260px, 320px) minmax(0, 1fr);
  gap: 24px;
  align-items: stretch;
}
.adder-command { padding: 24px; }
.drum-figure {
  appearance: none;
  border: 0;
  padding: 0;
  cursor: pointer;
  width: min(220px, 82%);
  aspect-ratio: 1;
  margin: 10px auto 16px;
  overflow: hidden;
  border-radius: 50%;
  background: #665a47;
  box-shadow: 0 0 0 1px rgba(43,36,27,.4), 0 10px 24px rgba(43,36,27,.2);
  transform-origin: 50% 60%;
}
.drum-figure img { width: 100%; height: 100%; object-fit: cover; mix-blend-mode: multiply; }
.drum-figure:focus-visible { outline: 3px solid var(--cinnabar); outline-offset: 5px; }
.drum-figure.strike { animation: drumStrike .42s ease-out; }
@keyframes drumStrike { 0%{transform:scale(1)} 32%{transform:scale(.94) rotate(-1deg)} 68%{transform:scale(1.035) rotate(1deg)} 100%{transform:scale(1)} }
.adder-inputs {
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  align-items: end;
  gap: 10px;
}
.adder-inputs label {
  display: grid;
  gap: 5px;
  font: .72rem var(--font-mono);
  color: var(--cinnabar);
}
.adder-inputs input {
  width: 100%;
  min-height: 48px;
  border: 1px solid rgba(43,36,27,.46);
  border-radius: 2px;
  background: rgba(255,248,226,.56);
  color: var(--paper-ink);
  font: 1.35rem var(--font-mono);
  text-align: center;
}
.adder-inputs input:focus-visible { outline: 2px solid var(--cinnabar); outline-offset: 2px; }
.adder-plus { padding-bottom: 8px; font: 1.5rem var(--font-serif); color: var(--cinnabar); }
.adder-actions { display: flex; gap: 8px; margin-top: 16px; }
.adder-status { min-height: 3em; margin: 15px 0 0; color: var(--paper-ink); font-family: var(--font-serif); }
.audio-note { margin: 8px 0 0; font: .68rem var(--font-mono); color: rgba(43,36,27,.65); }

.adder-machine {
  min-width: 0;
  padding: 22px;
  border: 1px solid rgba(183,154,97,.55);
  background: rgba(17,17,15,.92);
  box-shadow: inset 0 0 0 5px rgba(183,154,97,.035), 0 14px 36px rgba(0,0,0,.3);
}
.adder-equation {
  display: flex;
  align-items: center;
  justify-content: center;
  flex-wrap: wrap;
  gap: 10px;
  padding: 11px 14px;
  border-bottom: 1px solid rgba(183,154,97,.25);
  font-family: var(--font-mono);
  color: var(--gold-500);
}
.adder-equation strong { color: var(--paper-100); letter-spacing: .12em; }
.adder-result strong { color: var(--gold-300); }
.adder-result em { margin-left: 6px; color: var(--cinnabar-hover); font-style: normal; }
.adder-direction {
  display: grid;
  grid-template-columns: auto 1fr auto;
  align-items: center;
  gap: 10px;
  margin: 15px 0 8px;
  font: .66rem var(--font-mono);
  color: var(--gold-500);
}
.adder-direction i { height: 1px; background: linear-gradient(90deg, var(--cinnabar), var(--gold-300)); position: relative; }
.adder-direction i::after { content:""; position:absolute; right:0; top:-3px; border-left:6px solid var(--gold-300); border-top:3px solid transparent; border-bottom:3px solid transparent; }
.adder-stages {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 5px;
  min-height: 310px;
  overflow-x: visible;
  padding: 12px 2px 22px;
}
.adder-stage {
  flex: 0 0 135px;
  min-height: 260px;
  padding: 12px 10px;
  border: 1px solid rgba(183,154,97,.28);
  background: rgba(39,35,27,.64);
  text-align: center;
  transition: border-color .2s, box-shadow .2s, transform .2s, background .2s;
}
.adder-stage.active { border-color: var(--gold-300); background: rgba(125,52,41,.34); box-shadow: 0 0 18px rgba(183,154,97,.35); transform: translateY(-4px); }
.adder-stage.done { border-color: rgba(183,154,97,.6); }
.stage-head { display:flex; justify-content:space-between; font:.65rem var(--font-mono); color:var(--gold-500); }
.stage-values { display:grid; grid-template-columns:repeat(3,1fr); gap:5px; margin:12px 0 9px; }
.stage-value { padding:5px 2px; border:1px solid rgba(183,154,97,.28); font:.65rem var(--font-mono); color:var(--gold-500); }
.stage-value b { display:block; margin-top:2px; font-size:.95rem; color:var(--paper-100); }
.fa-symbol { display:grid; place-items:center; width:64px; height:48px; margin:0 auto 6px; border:1px solid var(--gold-500); background:var(--ink-950); font:.78rem var(--font-mono); color:var(--gold-300); }
.stage-output-soldier { position:relative; width:70px; height:80px; margin:0 auto 15px; }
.stage-output-soldier img { width:100%; height:100%; object-fit:contain; object-position:center bottom; }
.stage-sum-badge { position:absolute; left:50%; bottom:-12px; transform:translateX(-50%); min-width:24px; padding:2px 5px; border:1px solid var(--gold-500); background:var(--ink-950); font:.72rem var(--font-mono); color:var(--paper-100); }
.stage-carry-out { display:block; font:.65rem var(--font-mono); color:var(--gold-500); }
.stage-carry-out b { color:var(--gold-300); }
.carry-hop { flex:0 0 32px; display:grid; place-items:center; gap:4px; font:.52rem var(--font-mono); color:rgba(183,154,97,.45); }
.carry-hop::before { content:"CARRY"; }
.carry-hop::after { content:"→"; font-size:1.25rem; }
.carry-hop.active { color:var(--gold-300); text-shadow:0 0 8px rgba(183,154,97,.6); }
.adder-principle {
  display: grid;
  gap: 6px;
  padding: 13px 15px;
  border-top: 1px solid rgba(183,154,97,.25);
  color: rgba(223,207,170,.72);
  font-size: .85rem;
}
.adder-principle strong { color:var(--gold-300); }
.adder-principle code { color:var(--paper-100); font-family:var(--font-mono); }

/* ===== 收束区 ===== */
.closing {
  text-align: center;
  background: linear-gradient(180deg, var(--ink-950), var(--ink-900));
  max-width: none;
  padding-left: clamp(16px, 5vw, 64px);
  padding-right: clamp(16px, 5vw, 64px);
}
.closing-inner {
  max-width: 1060px;
  margin: 0 auto;
}
.closing h2 {
  font-family: var(--font-serif);
  font-size: clamp(1.6rem, 4vw, 2.4rem);
  color: var(--gold-300);
  margin: 0 0 28px;
  letter-spacing: .08em;
}
.closing-quote {
  font-family: var(--font-serif);
  font-size: clamp(1.3rem, 3.5vw, 2rem);
  color: var(--paper-100);
  line-height: 1.6;
  margin: 0 0 20px;
}
.closing-sub {
  font-size: 1rem;
  color: var(--gold-500);
  max-width: 40em;
  margin: 0 auto 32px;
}
.scale-vision {
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  align-items: stretch;
  gap: 14px;
  margin: 0 auto 30px;
  max-width: 980px;
}
.scale-endpoint, .scale-jump {
  display: flex;
  flex-direction: column;
  justify-content: center;
  padding: 18px;
  border: 1px solid rgba(183,154,97,.38);
  background: rgba(39,35,27,.52);
}
.scale-endpoint > span, .scale-jump > span { font: .7rem var(--font-mono); color: var(--gold-500); letter-spacing: .1em; }
.scale-endpoint strong { margin: 5px 0; font: 1.2rem var(--font-serif); color: var(--paper-100); }
.scale-endpoint small { color: rgba(223,207,170,.65); line-height: 1.45; }
.scale-endpoint-future { border-color: var(--gold-500); background: linear-gradient(135deg, rgba(125,52,41,.28), rgba(39,35,27,.72)); }
.scale-jump { border: none; background: transparent; padding-inline: 4px; }
.scale-jump strong { font: 1.1rem var(--font-mono); color: var(--gold-300); white-space: nowrap; }
.future-roadmap {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 14px;
  margin: 0 auto 30px;
}
.future-roadmap article {
  padding: 20px;
  border: 1px solid rgba(183,154,97,.36);
  background: linear-gradient(145deg, rgba(39,35,27,.72), rgba(17,17,15,.76));
  text-align: left;
}
.future-roadmap article > span { font:.68rem var(--font-mono); color:var(--cinnabar-hover); letter-spacing:.1em; }
.future-roadmap article strong { display:block; margin:7px 0 9px; font:1.08rem var(--font-serif); color:var(--gold-300); }
.future-roadmap article p { margin:0; font-size:.82rem; color:rgba(223,207,170,.68); line-height:1.7; }
.ladder {
  display: flex;
  align-items: center;
  justify-content: center;
  flex-wrap: wrap;
  gap: 10px;
  font-family: var(--font-mono);
  font-size: .9rem;
  color: var(--gold-300);
  margin: 0 0 28px;
}
.ladder span:not(.ladder-arrow) {
  padding: 6px 12px;
  border: 1px solid rgba(183,154,97,.4);
  border-radius: 2px;
  background: rgba(39,35,27,.5);
}
.ladder-arrow { color: var(--gold-500); }
.closing-facts {
  font-size: .92rem;
  color: rgba(223,207,170,.72);
  max-width: 46em;
  margin: 0 auto 32px;
  line-height: 1.8;
}

/* ===== 页脚 ===== */
.footer {
  border-top: 1px solid rgba(183,154,97,.25);
  padding: 24px clamp(16px, 5vw, 64px);
  text-align: center;
  background: var(--ink-950);
}
.footer p {
  font-family: var(--font-serif);
  font-size: .92rem;
  color: var(--gold-500);
  margin: 0 0 6px;
}
.footer-note {
  font-family: var(--font-mono);
  font-size: .72rem;
  color: rgba(183,154,97,.5);
  margin: 0;
}
.footer .asset-credit { margin-top: 9px; font: .66rem var(--font-mono); color: rgba(183,154,97,.42); }
.asset-credit a { color: rgba(223,207,170,.62); text-underline-offset: 3px; }
.asset-credit a:hover { color: var(--gold-300); }

/* ===== 图片降级棋子 ===== */
.fallback-pawn {
  display: inline-flex;
  flex-direction: column;
  align-items: center;
  width: 48px;
}
.pawn-head {
  width: 20px; height: 20px;
  background: var(--gold-500);
  border-radius: 50%;
}
.pawn-body {
  width: 28px; height: 32px;
  background: var(--ink-800);
  border: 1px solid var(--gold-500);
  border-radius: 2px;
  margin-top: 2px;
}

/* ===== 滚入动效 ===== */
.reveal {
  opacity: 0;
  transform: translateY(14px);
  transition: opacity .45s ease, transform .45s ease;
}
.reveal.in {
  opacity: 1;
  transform: none;
}

/* ===== 减少动态 ===== */
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  .reveal { opacity: 1; transform: none; transition: none; }
  .hint-arrow { animation: none; }
  .wire.active { animation: none; stroke-dashoffset: 0; }
  .lane-wire.active { animation: none; }
  .tl-fill, .tl-dot { transition: none; }
}

/* ========================================
   响应式 · 平板 720–1099px
   ======================================== */
@media (max-width: 1099px) {
  .principle-cards { grid-template-columns: repeat(2, 1fr); }
  .principle-cards .paper-card:last-child { grid-column: 1 / -1; max-width: 460px; margin: 0 auto; }
  .tutorial-grid { grid-template-columns: 1fr 1.4fr; }
  .truth-card { grid-column: 1 / -1; }
  .demo-body { grid-template-columns: 68% 32%; }
  .adder-lab { grid-template-columns: 1fr; }
  .adder-command { width: min(100%, 430px); margin-inline: auto; }
}

/* ========================================
   响应式 · 移动 0–719px
   ======================================== */
@media (max-width: 720px) {
  .topnav { height: 52px; padding: 0 14px; }
  .brand-sub { display: none; }
  .topnav-links { gap: 18px; }
  .topnav-links a { font-size: .95rem; }
  .nav-about { display: none; }

  .hero { min-height: 100svh; }
  .hero-content {
    margin-left: 0;
    padding: 0 7%;
    max-width: 100%;
    text-align: left;
    padding-top: 9vh;
  }
  .hero-title { font-size: clamp(2.8rem, 14vw, 4rem); }
  .hero-desc { font-size: 1rem; }
  .hero-hint { font-size: .72rem; }
  .scale-promise-hero { grid-template-columns: 1fr; gap: 3px; padding: 10px 12px; margin-top: 18px; }
  .scale-kicker, .scale-promise-hero > * { grid-column: 1; }
  .scale-multiplier { font-size: 1rem; }
  .scale-copy { font-size: .74rem; }
  .future-pills { margin-top: 5px; }
  .future-pills span { font-size: .6rem; }

  .section { padding: 56px 16px; }

  .principle-cards { grid-template-columns: 1fr; }
  .principle-cards .paper-card:last-child { max-width: none; }

  .tutorial-grid { grid-template-columns: 1fr; }

  .gate-stage { padding: 20px 14px; }
  .gate-soldier { width: 92px; height: 105px; }
  .gate-arena { min-height: 180px; gap: 4px; }

  /* Demo 移动端 */
  .demo-topbar {
    grid-template-columns: minmax(0, 1fr) 36px;
    height: auto;
    min-height: 56px;
    padding: 10px 12px;
    gap: 8px;
  }
  .demo-mode-label { white-space: nowrap; }
  .op-tabs { grid-column: 1 / -1; grid-row: 2; justify-content: center; }
  .demo-help { grid-column: 2; grid-row: 1; }
  .demo-phasebar { gap: 4px; padding: 7px 8px; }
  .phase-step { grid-template-columns: 22px auto; column-gap: 4px; padding: 5px 4px; }
  .phase-step b { width: 22px; height: 22px; font-size: .7rem; }
  .phase-step > span { font-size: .76rem; }
  .phase-step small { display: none; }
  .phase-arrow { font-size: .7rem; }
  .demo-body { grid-template-columns: 1fr; }
  .formation { border-right: none; border-bottom: 1px solid rgba(183,154,97,.25); min-height: 360px; }
  .bit-lane {
    grid-template-columns: 100px minmax(18px, 1fr) 48px minmax(18px, 1fr) 46px;
    min-height: 116px;
    gap: 3px;
  }
  .lane-soldier { width: 50px; height: 57px; }
  .lane-inputs .input-soldier .lane-soldier { width: 42px; height: 48px; }
  .lane-inputs .input-soldier .lane-bit { width: 16px; height: 16px; font-size: .62rem; }
  .lane-inputs .lane-label { font-size: .54rem; }
  .lane-bit { width: 20px; height: 20px; font-size: .76rem; }
  .gate-box { width: 44px; height: 36px; font-size: .62rem; }
  .lane-label { font-size: .62rem; }

  .info-panel { padding: 14px; gap: 10px; }
  .info-value { font-size: .98rem; }
  .info-value.mono { font-size: 1.05rem; }

  .demo-controls { flex-direction: column; align-items: stretch; gap: 14px; }
  .timeline { max-width: none; }

  .adder-lab { grid-template-columns: 1fr; }
  .adder-command { max-width: none; }
  .drum-figure { width: 180px; }
  .adder-machine { padding: 14px 12px; }
  .adder-equation { font-size: .78rem; gap: 7px; }
  .adder-stages { display: grid; grid-template-columns: 1fr; overflow: visible; min-height: 0; }
  .adder-stage { width: 100%; min-height: 240px; }
  .carry-hop { width: 100%; height: 32px; }
  .carry-hop::after { content: "↓"; }
  .adder-direction i::after { display: none; }

  .ladder { font-size: .78rem; gap: 6px; }
  .ladder span:not(.ladder-arrow) { padding: 5px 8px; }
  .scale-vision { grid-template-columns: 1fr; gap: 8px; }
  .scale-jump { padding: 4px; }
  .future-roadmap { grid-template-columns: 1fr; }
}

/* ========================================
   超小屏 320px
   ======================================== */
@media (max-width: 360px) {
  .bit-lane { grid-template-columns: 90px minmax(14px, 1fr) 42px minmax(14px, 1fr) 40px; gap: 2px; padding: 4px 2px; }
  .lane-soldier { width: 40px; height: 46px; }
  .lane-inputs .input-soldier .lane-soldier { width: 38px; height: 43px; }
  .lane-bit { width: 18px; height: 18px; font-size: .68rem; }
  .gate-box { width: 40px; height: 32px; font-size: .58rem; }
  .ctrl-buttons .btn { padding: 0 12px; font-size: .85rem; }
  .info-value.mono { font-size: .95rem; }
}