@charset "UTF-8";
:root {
  --paper: #eeeee7;
  --card: #fafbf6;
  --ink: #242c2b;
  --muted: #737a76;
  --line: #d8ded5;
  --accent: #da5637;
  --accent-soft: #f9e8df;
  --blue: #457d91;
  --blue-soft: #e6f0f2;
  --green: #557a50;
  --mono: "Cascadia Code", "SFMono-Regular", Consolas, monospace;
  --sans: "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif;
}
* {
  box-sizing: border-box;
}
body {
  margin: 0;
  background: var(--paper);
  color: var(--ink);
  font-family: var(--sans);
  -webkit-font-smoothing: antialiased;
}
button,
a {
  -webkit-tap-highlight-color: transparent;
}
button {
  font: inherit;
  cursor: pointer;
}
button:disabled {
  cursor: not-allowed;
  opacity: 0.45;
}
button:focus-visible,
input:focus-visible,
a:focus-visible,
pre:focus-visible {
  outline: 3px solid var(--blue);
  outline-offset: 4px;
}
button {
  transition:
    background 0.16s,
    transform 0.16s;
}
button:not(:disabled):active {
  transform: translateY(1px);
}
[hidden] {
  display: none !important;
}
::selection {
  background: #e9c1ac;
}
.app {
  min-height: 100svh;
  display: flex;
  flex-direction: column;
  max-width: 1800px;
  padding: 0 52px;
  margin: 0 auto;
}
.topbar {
  flex-shrink: 0;
  height: 94px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  border-bottom: 1px solid var(--line);
}
.brand {
  display: flex;
  gap: 14px;
  align-items: center;
  color: var(--ink);
  text-decoration: none;
  font-weight: 650;
  font-size: 17px;
  letter-spacing: 0.04em;
}
.brand-mark {
  width: 44px;
  height: 44px;
  display: grid;
  place-items: center;
  background: var(--accent);
  border-radius: 12px;
  color: #fff;
  font-size: 38px;
  font-weight: 400;
  line-height: 1;
}
.brand-en {
  display: block;
  font: 9px var(--mono);
  letter-spacing: 0.16em;
  color: var(--muted);
  margin-top: 5px;
}
.top-actions {
  display: flex;
  gap: 24px;
  align-items: center;
}
.icon-button {
  background: transparent;
  border: 1px solid #c6cdc3;
  color: var(--ink);
  width: 36px;
  height: 36px;
  border-radius: 8px;
  font-size: 24px;
}
.icon-button:hover {
  background: #e0e5dc;
}
.heading {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 28px;
  padding: 31px 0 25px;
}
.eyebrow {
  display: flex;
  align-items: center;
  gap: 12px;
  font-size: 11px;
  color: var(--muted);
  letter-spacing: 0.08em;
}
.eyebrow > span:first-child {
  color: var(--accent);
  font-weight: 650;
}
h1 {
  font-size: clamp(30px, 2.5vw, 46px);
  font-weight: 650;
  letter-spacing: -0.055em;
  margin: 12px 0 9px;
  line-height: 1.3;
}
.heading p {
  font-size: clamp(15px, 1.2vw, 20px);
  margin: 0;
  color: #65716a;
  line-height: 1.6;
}
.step-counter {
  flex-shrink: 0;
  text-align: right;
  padding-right: 3px;
}
.step-counter > span:first-child {
  font: 500 56px/1 var(--mono);
  letter-spacing: -0.07em;
}
.counter-total {
  font: 16px var(--mono);
  color: #8f968e;
  margin-left: 11px;
}
.chapter-track {
  display: grid;
  grid-template-columns: repeat(7, 1fr);
  margin-bottom: 24px;
}
.chapter-item {
  font-size: 13px;
  display: flex;
  gap: 11px;
  align-items: center;
  color: #81887f;
  border-top: 2px solid #d5dbd0;
  padding-top: 13px;
  position: relative;
}
.chapter-item > span {
  font: 10px var(--mono);
  color: #a2aaa0;
}
.chapter-item.current {
  color: var(--ink);
  border-color: var(--accent);
  font-weight: 650;
}
.chapter-item.current > span {
  color: var(--accent);
}
.chapter-item.complete {
  border-color: #a9b4a3;
  color: #788772;
}
.chapter-item:after {
  content: "";
  width: 9px;
  height: 4px;
  background: var(--paper);
  position: absolute;
  right: 0;
  top: -3px;
}
.workspace {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 340px;
  gap: 23px;
  align-items: stretch;
}
.stage-card {
  background: var(--card);
  border: 1px solid #d6ddd1;
  border-radius: 17px;
  overflow: hidden;
  min-width: 0;
  box-shadow: 0 5px 20px #24362603;
}
.stage-toolbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 19px 24px 13px;
}
.stage-label {
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 0.06em;
  display: flex;
  align-items: center;
  gap: 8px;
}
.stage-label > i {
  height: 7px;
  width: 7px;
  border-radius: 2px;
  background: var(--accent);
}
.principle-tag,
.live-tag {
  font-size: 10px;
  display: inline-flex;
  gap: 5px;
  align-items: center;
  line-height: 1.4;
  padding: 4px 8px;
  border-radius: 4px;
  letter-spacing: 0.03em;
  white-space: nowrap;
}
.principle-tag {
  color: #7b847c;
  background: #ecf0e8;
  border: 1px solid #e0e5dc;
}
.live-tag {
  color: var(--blue);
  background: var(--blue-soft);
  border: 1px solid #d6e5e9;
}
.live-tag i {
  width: 5px;
  height: 5px;
  border-radius: 50%;
  background: var(--blue);
}
.address-bar {
  margin: 0 24px;
  display: flex;
  gap: 12px;
  align-items: center;
  background: #f0f3eb;
  border: 1px solid #dce2d5;
  height: 43px;
  border-radius: 7px;
  padding: 0 13px;
  font: 14px var(--mono);
}
.muted {
  color: #889182;
}
.tiny-lock {
  color: #729069;
  font-size: 15px;
}
.address-bar input {
  min-width: 0;
  flex: 1;
  width: 100%;
  border: 0;
  background: transparent;
  color: var(--ink);
  font: inherit;
  padding: 5px 0;
}
.analyze-button {
  flex-shrink: 0;
  border: 0;
  border-radius: 4px;
  padding: 6px 9px;
  background: var(--accent);
  color: white;
  font: 12px var(--sans);
}
.address-status {
  margin: 6px 24px 0;
  font: 10px/1.5 var(--sans);
  color: var(--muted);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}
.address-status.invalid {
  color: #b24025;
}
.redirect-info p {
  margin: 9px 0;
  font-size: 11px;
  line-height: 1.5;
}
.network-map {
  padding: 0 15px;
  background-image: radial-gradient(#93a18b30 0.7px, transparent 0.7px);
  background-size: 15px 15px;
  margin-top: 8px;
}
.network-map svg {
  display: block;
  width: 100%;
  height: 213px;
}
.map-node > rect {
  fill: #f4f6ee;
  stroke: #d2dacb;
  stroke-width: 1.5;
}
.map-node .node-title {
  fill: #7e8878;
  font-size: 24px;
  font-weight: 600;
}
.map-node .node-subtitle {
  fill: #9aa28f;
  font-size: 13px;
  font-family: var(--sans);
}
.map-node.is-active > rect {
  fill: #fffaf1;
  stroke: #d8b68a;
}
.map-node.is-active .node-title {
  fill: #313b2d;
}
.map-node.is-active .node-subtitle {
  fill: #738064;
}
.node-icon {
  fill: none;
  stroke: #9caa8d;
  stroke-width: 1.6;
}
.map-node.is-active .node-icon {
  stroke: #a98559;
}
.dns-node.is-active > rect {
  fill: #eff7f6;
  stroke: #a8c6c9;
}
.dns-node.is-active .node-icon {
  stroke: var(--blue);
}
.map-route {
  fill: none;
  color: #d1d9ca;
  stroke: currentColor;
  stroke-width: 1.5;
}
.map-route path {
  marker-end: url(#arrow);
  stroke-dasharray: 4 5;
}
.map-route text {
  stroke: none;
  fill: #9ba78f;
  font: 11px var(--sans);
  text-anchor: middle;
  letter-spacing: 0.04em;
}
.map-route.flow-blue {
  color: var(--blue);
}
.map-route.flow-orange {
  color: var(--accent);
}
.map-route.flow-blue text {
  fill: #6e9a9d;
}
.map-route.flow-orange text {
  fill: #c68456;
}
.flow-orange path,
.flow-blue path {
  animation: flow 2.2s linear 2;
}
.return-route {
  opacity: 0.5;
}
.scene {
  min-height: 202px;
  margin: 0 24px 21px;
  border-top: 1px solid #e3e8db;
  padding-top: 15px;
  animation: reveal 0.24s ease-out;
}
.scene-footnote {
  font-size: 11px;
  line-height: 1.7;
  color: #8a927f;
  margin-top: 12px;
  text-align: center;
  overflow-wrap: anywhere;
}
.scene-heading {
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: 12px;
  color: #6c7866;
  margin-bottom: 10px;
}
.scene-overline {
  display: block;
  font-size: 10px;
  letter-spacing: 0.08em;
  color: #8b9681;
  margin-bottom: 10px;
}
.opening-scene {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: clamp(16px, 2.2vw, 35px);
  min-height: 143px;
}
.journey-end strong {
  font-size: 20px;
  font-weight: 550;
}
.journey-arrow {
  font-size: 24px;
  color: #a1b194;
  font-weight: 300;
}
.mystery {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  width: 152px;
  height: 124px;
  border: 1px dashed #db9a70;
  border-radius: 12px;
  background: #f8ecdd;
}
.mystery > span {
  font-size: 10px;
  color: #a77d53;
  letter-spacing: 0.04em;
}
.mystery > strong {
  font: 48px var(--mono);
  color: #ce7048;
  margin-top: 2px;
}
.explanation {
  border: 1px solid #d9dfd3;
  background: #e7ebdf;
  border-radius: 17px;
  padding: 25px 26px;
  display: flex;
  flex-direction: column;
  min-width: 0;
}
.explanation-top {
  display: flex;
  justify-content: space-between;
  align-items: center;
}
.small-label {
  font-size: 11px;
  letter-spacing: 0.09em;
  color: #7b866f;
}
.annotation-mark {
  font-size: 21px;
  color: #9da98f;
}
.explanation h2 {
  font-size: 24px;
  line-height: 1.6;
  letter-spacing: -0.03em;
  margin: 19px 0 12px;
  font-weight: 600;
}
.explanation > p {
  font-size: 15px;
  line-height: 1.95;
  margin: 0;
  color: #69745e;
}
.note-phrase {
  white-space: nowrap;
}
.data-panel {
  border-top: 1px solid #d2dac7;
  margin-top: 23px;
  padding-top: 19px;
  margin-bottom: 22px;
}
.data-heading {
  display: flex;
  align-items: center;
  gap: 10px;
}
.data-heading > span:last-child {
  font-size: 10px;
  color: #8a947d;
}
.metrics {
  margin: 10px 0 0;
}
.metrics > div {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 15px;
  padding: 9px 0;
  border-bottom: 1px solid #d9e0cf;
}
.metrics > div:last-child {
  border-bottom: none;
}
.metrics dt {
  font-size: 12px;
  color: #7e8971;
  flex-shrink: 0;
}
.metrics dd {
  margin: 0;
  font: 14px/1.6 var(--mono);
  text-align: right;
  color: #3e5346;
  overflow-wrap: anywhere;
}
.principle-caption > p {
  font-size: 13px;
  line-height: 1.85;
  color: #7b886c;
  margin: 10px 0 0;
}
.source {
  margin-top: auto;
  display: flex;
  gap: 9px;
  align-items: flex-start;
  padding-top: 10px;
}
.status-dot {
  display: block;
  width: 6px;
  height: 6px;
  border-radius: 50%;
  margin-top: 6px;
  background: #aaa;
  flex-shrink: 0;
}
.status-dot.success {
  background: #658c59;
}
.status-dot.error {
  background: var(--accent);
}
.status-dot.pending {
  background: #ad9565;
  animation: pulse 1.2s ease infinite;
}
.source strong {
  font-size: 10px;
  font-weight: 500;
  color: #7a886d;
}
.source p {
  font-size: 10px;
  line-height: 1.65;
  color: #97a188;
  margin: 5px 0 0;
  overflow-wrap: anywhere;
}
.controls {
  margin-top: auto;
  flex-shrink: 0;
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 23px 0 25px;
  gap: 20px;
}
.control-left,
.control-right {
  display: flex;
  align-items: center;
  gap: 12px;
}
.text-button {
  background: transparent;
  border: none;
  color: #7a8373;
  font-size: 12px;
  padding: 9px 0;
}
.text-button:hover {
  color: var(--ink);
}
.key-hint {
  font-size: 10px;
  color: #9ba390;
  margin-left: 20px;
  display: flex;
  gap: 5px;
  align-items: center;
}
kbd {
  font: 10px var(--mono);
  border: 1px solid #cbd4c0;
  min-width: 18px;
  height: 18px;
  border-radius: 3px;
  display: inline-grid;
  place-items: center;
  background: #f4f6ee;
  color: #839276;
}
.hint-divider {
  margin: 0 5px;
}
.next-label {
  font-size: 11px;
  color: #909a83;
  margin-right: 9px;
}
.previous-button {
  height: 44px;
  width: 46px;
  border: 1px solid #ccd5c0;
  background: #f7f8f1;
  border-radius: 7px;
  font-size: 22px;
  color: #748765;
}
.next-button {
  display: flex;
  gap: 37px;
  align-items: center;
  justify-content: space-between;
  height: 44px;
  min-width: 148px;
  padding: 0 17px;
  border: 1px solid #d95333;
  border-radius: 7px;
  background: var(--accent);
  color: #fff8f0;
  font-size: 13px;
  font-weight: 550;
  box-shadow: 0 2px 3px #b94a1e15;
}
.next-button span {
  font-size: 21px;
}
.next-button:hover:not(:disabled) {
  background: #bf4327;
}
.error-panel {
  margin-top: 13px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 18px;
  padding: 15px 21px;
  background: #f9e5dc;
  border: 1px solid #e6b8a4;
  border-radius: 10px;
}
.error-panel strong {
  font-size: 15px;
  color: #aa492e;
}
.error-panel p {
  font-size: 12px;
  color: #a5715a;
  margin: 6px 0 0;
  line-height: 1.6;
  overflow-wrap: anywhere;
}
.retry-button {
  font-size: 12px;
  white-space: nowrap;
  padding: 10px 15px;
  background: #fff5ee;
  border: 1px solid #ddaa91;
  border-radius: 6px;
  color: #a75534;
}
.url-parts {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(0, 2.2fr) minmax(0, 1fr) minmax(
      0,
      2fr
    );
  gap: 10px;
  align-items: center;
  min-height: 144px;
}
.url-parts > div {
  display: flex;
  flex-direction: column;
  gap: 20px;
  align-items: center;
  min-width: 0;
}
.url-parts strong {
  font: clamp(15px, 1.55vw, 24px) var(--mono);
  white-space: nowrap;
  color: #496957;
  max-width: 100%;
  overflow: hidden;
  text-overflow: ellipsis;
}
.url-parts strong > span {
  color: #a1b196;
}
.url-parts label {
  font-size: 11px;
  color: #89977d;
  border-top: 1px solid #d4dfca;
  padding-top: 12px;
  width: 100%;
  text-align: center;
}
.url-parts .port-part strong {
  color: var(--accent);
}
.cache-flow,
.tls-sequence {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 12px;
  min-height: 140px;
}
.cache-flow > div {
  display: flex;
  flex-direction: column;
  gap: 10px;
}
.cache-flow > div > span {
  font: 11px var(--mono);
  color: #b0bba4;
}
.cache-flow strong,
.tls-sequence strong {
  font-size: 17px;
  font-weight: 550;
}
.cache-flow small,
.tls-sequence small {
  font-size: 10px;
  color: #8d9a80;
  line-height: 1.6;
}
.cache-flow > b {
  font-weight: 300;
  color: #bdc8b3;
}
.records {
  padding: 1px 0;
}
.record-row {
  display: flex;
  gap: 12px;
  align-items: center;
  padding: 10px 4px;
  border-bottom: 1px solid #e5ebdd;
}
.record-row:last-child {
  border: none;
}
.record-type {
  font: 10px var(--mono);
  color: var(--blue);
  width: 40px;
  background: #e9f2f0;
  border-radius: 4px;
  padding: 4px;
  text-align: center;
  flex-shrink: 0;
}
.record-row > code {
  font: 16px var(--mono);
  color: #4b6954;
  overflow-wrap: anywhere;
  min-width: 0;
}
.record-ttl {
  margin-left: auto;
  font: 10px var(--mono);
  color: #9bac8c;
  white-space: nowrap;
}
.address-result {
  min-height: 144px;
  text-align: center;
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  gap: 12px;
}
.address-result > strong {
  font: clamp(18px, 2vw, 30px) var(--mono);
  color: #416047;
  overflow-wrap: anywhere;
  max-width: 100%;
}
.address-result .scene-overline {
  margin: 0;
}
.address-result > div {
  display: flex;
  gap: 10px;
}
.port-doors {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 14px;
  padding-top: 8px;
}
.port-doors > div {
  display: flex;
  flex-direction: column;
  padding: 14px 17px;
  border: 1px solid #dee7d5;
  border-radius: 8px;
  gap: 8px;
  color: #98a58b;
  background: #f5f8ee;
}
.port-doors > div.selected-door {
  border-color: #ddb294;
  background: #fbf0e0;
  color: #955d32;
}
.port-doors > div > span {
  font: 22px var(--mono);
}
.port-doors strong {
  font-size: 15px;
  font-weight: 500;
}
.port-doors small {
  font-size: 10px;
  opacity: 0.7;
}
.port-doors i {
  font: 9px var(--sans);
  color: #bb8a5f;
  white-space: nowrap;
}
.handshake {
  display: flex;
  flex-direction: column;
  gap: 8px;
  padding: 3px 4px;
}
.handshake > div {
  display: flex;
  align-items: center;
  gap: 15px;
  padding: 9px 12px;
  background: #f0f5e9;
  border-radius: 5px;
}
.handshake > div > span {
  font: 10px var(--mono);
  color: #9aab89;
}
.handshake strong {
  font: 14px var(--mono);
  width: 112px;
  flex-shrink: 0;
  color: #708c54;
}
.handshake i {
  font-style: normal;
  font-size: 11px;
  color: #96a684;
}
.handshake b {
  flex: 1;
  font-size: 17px;
  text-align: center;
  color: var(--accent);
}
.handshake .back {
  color: var(--blue);
}
.handshake small {
  font-size: 10px;
  color: #a8b698;
  margin-left: auto;
}
.tls-sequence > div {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 10px;
  text-align: center;
  flex: 1;
}
.tls-symbol {
  font-size: 25px;
  color: #638256;
  height: 40px;
  width: 40px;
  background: #edf3e6;
  border-radius: 50%;
  display: grid;
  place-items: center;
}
.code-block {
  white-space: pre;
  overflow: auto;
  max-height: 193px;
  margin: 0;
  padding: 15px 18px;
  border: 1px solid #dfe7d4;
  border-radius: 8px;
  background: #eff4e7;
  color: #506c40;
  font: 15px/1.7 var(--mono);
  scrollbar-width: thin;
  scrollbar-color: #c7d7b5 transparent;
}
.code-block code {
  font: inherit;
}
.process-scene {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 25px;
  min-height: 143px;
}
.process-ring {
  height: 66px;
  width: 66px;
  border: 1px dashed #bdccac;
  background: #eff4e8;
  color: #769758;
  border-radius: 50%;
  display: grid;
  place-items: center;
  font-size: 36px;
}
.process-scene strong {
  font-size: 21px;
  font-weight: 500;
  color: #5b7649;
}
.process-scene p {
  font-size: 12px;
  color: #9baa8e;
  margin: 12px 0;
}
.render-pipeline {
  display: flex;
  gap: 13px;
  font-size: 11px;
  color: #8aa070;
  align-items: center;
  justify-content: center;
  margin-bottom: 12px;
}
.render-pipeline b {
  font-weight: 400;
  color: #bdcdb0;
}
.render-scene iframe {
  display: block;
  width: 100%;
  height: 152px;
  background: #fff;
  border: 1px solid #d7e3ca;
  border-radius: 7px;
}
.recap-flow {
  display: grid;
  grid-template-columns: repeat(6, 1fr);
  gap: 8px;
  min-height: 141px;
  align-items: center;
}
.recap-flow > div {
  display: flex;
  flex-direction: column;
  gap: 13px;
  align-items: center;
  border-right: 1px solid #e0e9d5;
  min-width: 0;
}
.recap-flow > div:last-child {
  border: none;
}
.recap-flow span {
  font: 10px var(--mono);
  color: #aabd98;
}
.recap-flow strong {
  font-size: 23px;
  font-weight: 550;
  color: #637e4b;
}
.recap-flow small {
  font-size: 9px;
  color: #99ac86;
  text-align: center;
  line-height: 1.7;
}
.diagnostic-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 16px 17px;
  padding: 8px 0;
}
.diagnostic-grid > div {
  display: grid;
  grid-template-columns: 24px 1fr;
  gap: 7px 8px;
}
.diagnostic-grid span {
  font: 10px var(--mono);
  color: #a4b593;
  grid-row: span 2;
  padding-top: 4px;
}
.diagnostic-grid strong {
  font-size: 16px;
  font-weight: 500;
  color: #68864d;
}
.diagnostic-grid small {
  font-size: 10px;
  color: #9db288;
  line-height: 1.6;
}
.placeholder {
  display: flex;
  justify-content: center;
  align-items: center;
  gap: 14px;
  min-height: 153px;
  font-size: 13px;
  color: #a3b591;
}
.placeholder-orbit {
  width: 22px;
  height: 22px;
  border: 1px dashed #a9be8f;
  border-radius: 50%;
}
@keyframes flow {
  to {
    stroke-dashoffset: -36;
  }
}
@keyframes pulse {
  50% {
    opacity: 0.35;
  }
}
@keyframes reveal {
  from {
    opacity: 0.35;
    transform: translateY(4px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}
@media (min-width: 1600px) {
  .app {
    padding: 0 70px;
  }
  .topbar {
    height: 103px;
  }
  .heading {
    padding: 35px 0 29px;
  }
  .workspace {
    grid-template-columns: minmax(0, 1fr) 380px;
    gap: 28px;
  }
  .explanation {
    padding: 28px 30px;
  }
  .explanation h2 {
    font-size: 27px;
  }
  .explanation > p {
    font-size: 17px;
  }
  .network-map svg {
    height: 245px;
  }
  .scene {
    min-height: 230px;
  }
  .opening-scene,
  .cache-flow,
  .tls-sequence,
  .address-result,
  .process-scene {
    min-height: 172px;
  }
  .scene-footnote {
    font-size: 12px;
  }
  .code-block {
    font-size: 18px;
    max-height: 219px;
  }
  .source strong,
  .source p {
    font-size: 11px;
  }
  .scene-heading {
    font-size: 14px;
  }
  .principle-caption > p {
    font-size: 15px;
  }
  .record-row > code {
    font-size: 19px;
  }
  .handshake > div {
    padding: 12px;
  }
  .handshake i {
    font-size: 13px;
  }
  .handshake strong {
    font-size: 17px;
  }
  .recap-flow {
    min-height: 178px;
  }
  .recap-flow small {
    font-size: 11px;
  }
  .controls {
    padding-top: 26px;
  }
  .next-button,
  .previous-button {
    height: 49px;
  }
  .metrics dt {
    font-size: 14px;
  }
  .metrics dd {
    font-size: 16px;
  }
}
@media (max-width: 1150px) {
  .app {
    padding: 0 28px;
  }
  .workspace {
    grid-template-columns: minmax(0, 1fr) 285px;
    gap: 16px;
  }
  .explanation {
    padding: 20px;
  }
  .explanation h2 {
    font-size: 21px;
  }
  .explanation > p {
    font-size: 14px;
  }
  .stage-toolbar {
    padding: 15px 18px 11px;
  }
  .address-bar {
    margin: 0 18px;
    font-size: 12px;
  }
  .scene {
    margin-left: 18px;
    margin-right: 18px;
  }
  .network-map {
    padding: 0 5px;
  }
  .network-map svg {
    height: 193px;
  }
  .opening-scene {
    gap: 16px;
  }
  .mystery {
    width: 121px;
  }
  .journey-end strong {
    font-size: 17px;
  }
  .next-label {
    display: none;
  }
  .key-hint {
    margin-left: 10px;
  }
  .url-parts {
    gap: 6px;
    grid-template-columns:
      minmax(0, 1fr) minmax(0, 2.2fr) minmax(0, 1fr)
      minmax(0, 2fr);
  }
  .url-parts strong {
    font-size: 14px;
  }
  .url-parts label {
    font-size: 9px;
  }
  .cache-flow strong,
  .tls-sequence strong {
    font-size: 14px;
  }
  .handshake {
    padding: 0;
  }
  .handshake > div {
    gap: 8px;
    padding: 10px 8px;
  }
  .handshake strong {
    width: 95px;
    font-size: 12px;
  }
  .handshake small {
    display: none;
  }
  .record-row > code {
    font-size: 13px;
  }
  .record-ttl {
    font-size: 9px;
  }
  .chapter-item {
    font-size: 11px;
    gap: 8px;
  }
}
@media (max-width: 850px) {
  .app {
    padding: 0 20px;
  }
  .topbar {
    height: 77px;
  }
  .brand {
    font-size: 15px;
  }
  .heading {
    padding: 24px 0 21px;
  }
  .heading p {
    font-size: 14px;
  }
  .step-counter > span:first-child {
    font-size: 40px;
  }
  .counter-total {
    font-size: 12px;
  }
  .workspace {
    grid-template-columns: 1fr;
  }
  .explanation {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 0 25px;
  }
  .explanation-top,
  .explanation h2,
  .explanation > p {
    grid-column: 1;
  }
  .explanation h2 {
    margin: 10px 0;
  }
  .data-panel {
    grid-column: 2;
    grid-row: 1 / span 3;
    margin: 0;
    border-top: none;
    border-left: 1px solid #cfdbbf;
    padding: 4px 0 0 23px;
  }
  .source {
    grid-column: 1 / -1;
    margin-top: 15px;
  }
  .network-map svg {
    height: 207px;
  }
  .chapter-track {
    margin-bottom: 18px;
  }
  .chapter-item {
    font-size: 10px;
    gap: 5px;
  }
  .chapter-item > span {
    font-size: 8px;
  }
  .stage-card .scene {
    min-height: 198px;
  }
  .controls {
    position: sticky;
    bottom: 0;
    background: var(--paper);
    padding: 15px 0;
    border-top: 1px solid #d4dfc9;
    margin-top: 18px;
    z-index: 2;
  }
  .network-map svg .node-subtitle {
    font-size: 13px;
  }
  .recap-flow small {
    font-size: 10px;
  }
  .error-panel {
    align-items: flex-start;
  }
  .error-panel p {
    font-size: 11px;
  }
}
@media (max-width: 520px) {
  .app {
    padding: 0 14px;
  }
  .brand-mark {
    width: 35px;
    height: 35px;
    border-radius: 9px;
    font-size: 30px;
  }
  .brand {
    gap: 10px;
    font-size: 14px;
  }
  .brand-en {
    font-size: 7px;
  }
  .topbar {
    height: 67px;
  }
  .heading {
    gap: 13px;
    align-items: flex-start;
    padding-top: 22px;
  }
  .heading h1 {
    font-size: 27px;
    margin: 12px 0 9px;
  }
  .heading p {
    font-size: 12px;
  }
  .eyebrow {
    font-size: 8px;
    gap: 7px;
  }
  .step-counter {
    padding-top: 22px;
  }
  .step-counter > span:first-child {
    font-size: 31px;
  }
  .counter-total {
    font-size: 10px;
    margin-left: 6px;
  }
  .chapter-track {
    grid-template-columns: repeat(3, 1fr);
    gap: 13px 0;
  }
  .chapter-item {
    font-size: 10px;
    padding-top: 7px;
  }
  .chapter-item > span {
    font-size: 9px;
  }
  .stage-toolbar {
    padding: 12px;
  }
  .stage-label {
    font-size: 10px;
  }
  .principle-tag,
  .live-tag {
    font-size: 8px;
    padding: 3px 5px;
  }
  .address-bar {
    margin: 0 12px;
    font-size: 10px;
    gap: 6px;
    height: 36px;
  }
  .analyze-button {
    font-size: 10px;
    padding: 5px;
  }
  .address-status {
    margin-left: 12px;
    margin-right: 12px;
  }
  .network-map {
    margin-top: 0;
  }
  .network-map svg {
    height: 154px;
  }
  .scene {
    padding-top: 10px;
    margin: 0 12px 15px;
  }
  .scene-footnote {
    font-size: 9px;
    margin-top: 10px;
  }
  .stage-card .scene {
    min-height: 161px;
  }
  .opening-scene {
    min-height: 128px;
    gap: 12px;
  }
  .journey-end strong {
    font-size: 14px;
  }
  .scene-overline {
    font-size: 8px;
  }
  .journey-arrow {
    font-size: 15px;
  }
  .mystery {
    width: 108px;
    height: 104px;
  }
  .mystery > span {
    font-size: 8px;
  }
  .mystery > strong {
    font-size: 39px;
  }
  .explanation {
    display: flex;
    padding: 19px;
  }
  .explanation h2 {
    font-size: 20px;
  }
  .explanation > p {
    font-size: 14px;
  }
  .data-panel {
    border-left: none;
    border-top: 1px solid #cfdbbf;
    padding: 15px 0 0;
    margin: 16px 0 0;
  }
  .metrics > div {
    padding: 6px 0;
  }
  .source {
    padding-top: 0;
  }
  .controls {
    gap: 8px;
  }
  .control-left {
    gap: 5px;
  }
  .key-hint {
    display: none;
  }
  .control-right {
    gap: 8px;
  }
  .next-button {
    gap: 20px;
    min-width: 115px;
    height: 41px;
    font-size: 12px;
    padding: 0 13px;
  }
  .previous-button {
    width: 38px;
    height: 41px;
  }
  .text-button {
    font-size: 10px;
  }
  .url-parts {
    grid-template-columns: minmax(0, 1fr) minmax(0, 2.5fr);
    gap: 15px;
  }
  .url-parts > div {
    gap: 8px;
  }
  .url-parts strong {
    font-size: 14px;
  }
  .url-parts label {
    padding-top: 6px;
  }
  .cache-flow {
    gap: 5px;
    min-height: 123px;
  }
  .cache-flow strong {
    font-size: 12px;
  }
  .cache-flow small {
    font-size: 8px;
    max-width: 85px;
  }
  .cache-flow > div {
    gap: 8px;
  }
  .record-row {
    gap: 7px;
    padding: 8px 0;
  }
  .record-type {
    font-size: 8px;
    width: 33px;
  }
  .record-row > code {
    font-size: 10px;
  }
  .record-ttl {
    font-size: 8px;
  }
  .address-result {
    min-height: 124px;
  }
  .address-result > strong {
    font-size: 18px;
  }
  .port-doors {
    gap: 7px;
  }
  .port-doors > div {
    padding: 11px 9px;
  }
  .port-doors > div > span {
    font-size: 20px;
  }
  .port-doors i {
    display: block;
    font-size: 8px;
    margin-top: 3px;
  }
  .port-doors strong {
    font-size: 12px;
  }
  .port-doors small {
    font-size: 9px;
  }
  .handshake > div {
    gap: 6px;
    padding: 8px 5px;
  }
  .handshake strong {
    font-size: 11px;
    width: 85px;
  }
  .handshake i {
    font-size: 9px;
  }
  .handshake > div > span {
    font-size: 9px;
  }
  .tls-sequence {
    gap: 5px;
    min-height: 130px;
  }
  .tls-sequence strong {
    font-size: 12px;
  }
  .tls-sequence small {
    font-size: 8px;
    max-width: 95px;
  }
  .code-block {
    font-size: 11px;
    max-height: 163px;
    padding: 10px;
  }
  .scene-heading {
    font-size: 10px;
  }
  .process-scene {
    gap: 13px;
    min-height: 121px;
  }
  .process-ring {
    height: 49px;
    width: 49px;
    font-size: 27px;
  }
  .process-scene strong {
    font-size: 16px;
  }
  .process-scene p {
    font-size: 10px;
  }
  .render-pipeline {
    gap: 8px;
    font-size: 9px;
  }
  .render-scene iframe {
    height: 146px;
  }
  .recap-flow {
    grid-template-columns: repeat(3, 1fr);
    gap: 16px 5px;
  }
  .recap-flow > div {
    gap: 5px;
  }
  .recap-flow strong {
    font-size: 18px;
  }
  .recap-flow small {
    font-size: 9px;
  }
  .recap-flow span {
    font-size: 8px;
  }
  .recap-flow > div:nth-child(3) {
    border: none;
  }
  .diagnostic-grid {
    grid-template-columns: repeat(2, 1fr);
    gap: 13px 11px;
  }
  .diagnostic-grid > div {
    grid-template-columns: 15px 1fr;
    gap: 5px;
  }
  .diagnostic-grid strong {
    font-size: 13px;
  }
  .diagnostic-grid small {
    font-size: 9px;
  }
  .diagnostic-grid span {
    font-size: 8px;
  }
  .error-panel {
    flex-direction: column;
    padding: 15px;
    gap: 12px;
  }
  .error-panel strong {
    font-size: 14px;
  }
}
@media (min-width: 851px) {
  .app {
    --small-font: clamp(13px, 0.85vw, 16px);
    --ui-font: clamp(17px, 1.05vw, 21px);
    max-width: 1920px;
    padding: 0 clamp(24px, 2.2vw, 44px);
  }
  .app > main {
    flex: 1;
    display: flex;
    flex-direction: column;
  }
  .topbar {
    height: clamp(54px, 7vh, 76px);
  }
  .brand {
    font-size: clamp(20px, 1.4vw, 26px);
  }
  .brand-en {
    font-size: 11px;
    color: #63705c;
  }
  .heading {
    padding: clamp(8px, 1.2vh, 16px) 0;
  }
  .heading > div:first-child {
    display: grid;
    grid-template-columns: auto 1fr;
    column-gap: 16px;
    align-items: center;
    min-width: 0;
  }
  .eyebrow {
    font-size: var(--small-font);
  }
  h1 {
    font-size: clamp(30px, 2.3vw, 44px);
    margin: 0;
  }
  .heading p {
    grid-column: 1 / -1;
    font-size: clamp(16px, 1.1vw, 21px);
    margin-top: 5px;
  }
  .step-counter > span:first-child {
    font-size: clamp(42px, 3.4vw, 62px);
  }
  .chapter-track {
    margin-bottom: 12px;
  }
  .chapter-item {
    padding: 10px 0 4px;
    font-size: var(--ui-font);
    font-weight: 550;
    gap: 10px;
    color: #64705e;
  }
  .chapter-item > span {
    font-size: var(--small-font);
    color: #708063;
  }
  .chapter-item.current {
    color: var(--ink);
    font-weight: 700;
  }
  .chapter-item.current > span {
    color: var(--accent);
  }
  .workspace {
    flex: 1;
    grid-template-columns: minmax(0, 1fr) clamp(350px, 26vw, 470px);
    gap: 20px;
  }
  .stage-card {
    display: flex;
    flex-direction: column;
  }
  .stage-toolbar {
    padding: 9px 20px 7px;
  }
  .address-bar {
    height: 42px;
    flex-shrink: 0;
    margin: 0 20px;
    font-size: clamp(16px, 1.1vw, 21px);
  }
  .analyze-button {
    font-size: 14px;
  }
  .address-status {
    font-size: var(--small-font);
    margin: 4px 20px 0;
  }
  .network-map {
    padding: 0 12px;
    margin-top: 0;
  }
  .network-map svg {
    height: auto;
  }
  .map-node .node-title {
    font-size: 26px;
    fill: #607054;
  }
  .map-node.is-active .node-title {
    fill: #313b2d;
  }
  .map-node .node-subtitle {
    font-size: 15px;
    fill: #66765c;
  }
  .map-route text {
    font-size: 14px;
    fill: #718166;
  }
  .scene {
    flex: 1;
    display: flex;
    flex-direction: column;
    justify-content: center;
    min-height: clamp(168px, 20vh, 235px);
    margin: 0 20px 12px;
    padding-top: 10px;
  }
  .scene-heading {
    margin-bottom: 8px;
  }
  .scene-footnote {
    margin-top: 8px;
  }
  .stage-label,
  .scene-heading,
  .render-pipeline,
  .metrics dt,
  .principle-caption > p {
    font-size: clamp(15px, 1vw, 19px);
  }
  .principle-tag,
  .live-tag,
  .small-label,
  .scene-overline,
  .scene-footnote,
  .source strong,
  .source p,
  .data-heading > span:last-child,
  .url-parts label,
  .cache-flow small,
  .tls-sequence small,
  .port-doors small,
  .port-doors i,
  .handshake i,
  .handshake small,
  .handshake > div > span,
  .process-scene p,
  .recap-flow span,
  .recap-flow small,
  .diagnostic-grid span,
  .diagnostic-grid small,
  .record-ttl {
    font-size: var(--small-font);
    color: #66765b;
  }
  .principle-tag,
  .live-tag {
    padding: 3px 7px;
  }
  .live-tag {
    color: var(--blue);
  }
  .opening-scene,
  .cache-flow,
  .tls-sequence,
  .address-result,
  .process-scene,
  .recap-flow,
  .url-parts {
    min-height: clamp(130px, 16vh, 195px);
  }
  .opening-scene {
    gap: clamp(30px, 3.5vw, 68px);
  }
  .journey-end strong,
  .recap-flow strong {
    font-size: clamp(26px, 2vw, 36px);
  }
  .mystery {
    width: clamp(180px, 13vw, 250px);
    height: clamp(120px, 15vh, 175px);
  }
  .mystery > span {
    font-size: var(--small-font);
  }
  .mystery > strong {
    font-size: 60px;
  }
  .cache-flow strong,
  .tls-sequence strong,
  .process-scene strong,
  .diagnostic-grid strong {
    font-size: clamp(19px, 1.4vw, 26px);
  }
  .url-parts strong {
    font-size: clamp(19px, 1.5vw, 28px);
  }
  .explanation {
    padding: clamp(18px, 1.5vw, 28px);
  }
  .explanation h2 {
    font-size: clamp(22px, 1.6vw, 30px);
    line-height: 1.4;
    margin: 12px 0;
    text-wrap: balance;
  }
  .explanation > p {
    font-size: clamp(16px, 1.1vw, 21px);
    line-height: 1.7;
  }
  .data-panel {
    margin: 14px 0;
    padding-top: 12px;
  }
  .metrics > div {
    padding: 6px 0;
  }
  .metrics dd {
    font-size: clamp(16px, 1.1vw, 21px);
  }
  .code-block {
    max-height: clamp(162px, 21vh, 250px);
    font-size: clamp(18px, 1.15vw, 22px);
    line-height: 1.5;
    padding: 10px 14px;
  }
  .scene-html .code-block {
    white-space: pre-wrap;
    overflow-wrap: anywhere;
  }
  .record-row {
    padding: 5px 4px;
  }
  .record-type {
    font-size: 12px;
    width: 48px;
  }
  .record-row > code {
    font-size: clamp(17px, 1.2vw, 23px);
  }
  .handshake > div {
    padding: 7px 12px;
  }
  .handshake strong {
    font-size: 17px;
  }
  .render-scene iframe {
    height: clamp(150px, 20vh, 240px);
  }
  .render-pipeline {
    margin-bottom: 8px;
  }
  .controls {
    margin-top: 0;
    padding: 12px 0;
    position: sticky;
    bottom: 0;
    background: var(--paper);
    z-index: 2;
  }
  .text-button {
    font-size: var(--ui-font);
    color: #4f6449;
    border: 1px solid #c5cfbc;
    border-radius: 7px;
    padding: 9px 12px;
    background: #f7f8f1;
  }
  .key-hint,
  .next-label {
    font-size: clamp(14px, 0.95vw, 18px);
    color: #63735a;
  }
  kbd {
    font-size: 14px;
    min-width: 28px;
    height: 28px;
    color: #536848;
  }
  .next-button,
  .previous-button {
    height: 48px;
  }
  .next-button {
    font-size: var(--ui-font);
    min-width: 165px;
  }
  .error-panel strong {
    font-size: 17px;
  }
  .error-panel p,
  .retry-button {
    font-size: 14px;
  }
}
@media (min-width: 851px) and (max-height: 900px) {
  .network-map svg {
    max-height: 25vh;
  }
}
@media (min-width: 851px) and (max-height: 790px) {
  .topbar {
    height: 50px;
  }
  .heading {
    padding: 4px 0;
  }
  .chapter-track {
    margin-bottom: 8px;
  }
  .chapter-item {
    padding-top: 7px;
  }
  .controls {
    padding: 6px 0;
  }
  .scene {
    padding-top: 8px;
    margin-bottom: 10px;
  }
  .explanation {
    padding: 18px;
  }
  .explanation h2 {
    margin: 10px 0;
  }
  .explanation > p {
    line-height: 1.65;
  }
  .data-panel {
    margin: 10px 0;
  }
}
@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation: none !important;
    transition: none !important;
    scroll-behavior: auto !important;
  }
}