/* 首屏沿用已确认的暖墨画布与实体轮廓，不绘制应用界面。 */
.hero {
  padding: var(--edge) var(--edge) 0;
}

.hero__canvas {
  position: relative;
  isolation: isolate;
  overflow: hidden;
  height: clamp(640px, calc(100vh - var(--head-h) - var(--edge) - 56px), 780px);
  padding-inline: var(--canvas-pad);
  border-radius: var(--r-canvas);
  color: var(--c-on-canvas);
  background:
    radial-gradient(90% 85% at 100% 0%, var(--c-amber-core) 0%, var(--c-amber-mid) 32%, var(--c-clear) 64%),
    radial-gradient(70% 70% at 0% 100%, var(--c-shade), var(--c-clear) 70%),
    var(--c-canvas);
  display: grid;
  grid-template-columns: minmax(0, 1fr) var(--stage-col);
  gap: 40px;
  align-items: center;
}

.hero__canvas::after {
  content: "";
  position: absolute;
  inset: 0;
  z-index: -1;
  pointer-events: none;
  background:
    linear-gradient(112deg, var(--c-clear) 52%, var(--c-amber-shaft) 56%, var(--c-clear) 61%),
    linear-gradient(112deg, var(--c-clear) 64%, var(--c-amber-shaft) 67.5%, var(--c-clear) 72%);
  color: var(--c-on-canvas);
  -webkit-mask-image: radial-gradient(120% 100% at 100% 0%, var(--c-mask) 20%, var(--c-clear) 72%);
  mask-image: radial-gradient(120% 100% at 100% 0%, var(--c-mask) 20%, var(--c-clear) 72%);
}

.hero__copy {
  position: relative;
  z-index: 2;
  max-width: 580px;
  min-width: 0;
}

.badge {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  min-height: 32px;
  max-width: 100%;
  padding: 5px 14px 5px 12px;
  margin-bottom: 22px;
  border: 1px solid var(--c-border);
  border-radius: var(--r-pill);
  background: var(--c-panel);
  color: var(--c-muted);
  font-size: 13px;
  font-weight: var(--fw-semibold);
  overflow-wrap: anywhere;
}

.badge__dot {
  width: 8px;
  height: 8px;
  flex-shrink: 0;
  border-radius: var(--r-circle);
  background: var(--c-accent);
  color: var(--c-text);
  box-shadow: 0 0 0 4px var(--c-accent-ring), 0 0 14px var(--c-accent-glow);
}

.hero .badge {
  border-color: var(--c-canvas-line);
  background: var(--c-canvas-fill);
  color: var(--c-on-canvas-muted);
}

.hero__title {
  margin: 0 0 30px;
  font-size: var(--fs-h1);
  line-height: 1.18;
  color: var(--c-on-canvas);
}

.hero__title-line {
  display: block;
}

.hero__title em {
  font-style: normal;
  color: var(--c-accent);
}

.hero__actions {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 12px;
  margin-bottom: 28px;
}

.hero__desc {
  max-width: 520px;
  margin: 0 0 20px;
  color: var(--c-on-canvas-muted);
  font-size: 15.5px;
  line-height: 1.72;
}

.hero__desc strong {
  color: var(--c-on-canvas);
}

.chip-row,
.fact-row {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  min-width: 0;
  padding: 0;
  list-style: none;
}

.chip-row {
  margin: 0 0 26px;
}

.chip,
.fact-pill {
  display: inline-flex;
  align-items: center;
  gap: 7px;
  max-width: 100%;
  min-height: 30px;
  padding: 5px 13px;
  border: 1px solid var(--c-border);
  border-radius: var(--r-pill);
  background: var(--c-bg);
  color: var(--c-muted);
  font-size: 13px;
  line-height: 1.45;
  overflow-wrap: anywhere;
}

.chip svg,
.fact-pill svg {
  width: 13px;
  height: 13px;
  color: var(--c-accent-dark);
}

.hero .chip {
  border-color: var(--c-canvas-line);
  background: var(--c-clear);
  color: var(--c-on-canvas-muted);
}

.hero .chip svg {
  color: var(--c-accent);
}

.fact-row {
  margin: 24px 0;
}

.fact-pill strong {
  color: var(--c-text);
}

.fact-pill--wide {
  border-radius: var(--r-card);
}

.device-row {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 10px 22px;
  padding-top: 20px;
  border-top: 1px solid var(--c-canvas-line-soft);
}

.device {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  min-height: 28px;
  font-size: 13.5px;
  font-weight: var(--fw-medium);
  color: var(--c-on-canvas-muted);
  white-space: nowrap;
}

.device svg {
  width: 19px;
  height: 19px;
  color: var(--c-on-canvas-muted);
}

.device:hover {
  color: var(--c-accent);
}

.device--store {
  padding: 3px 12px 3px 10px;
  border: 1px solid var(--c-canvas-line-strong);
  border-radius: var(--r-pill);
  color: var(--c-on-canvas);
}

.device--store svg {
  width: 14px;
  height: 14px;
  color: var(--c-on-canvas);
}

.stage {
  position: relative;
  z-index: 1;
  height: 100%;
  min-width: 0;
  margin: 0;
}

.stage__frame {
  position: absolute;
  left: 50%;
  top: 50%;
  width: 620px;
  height: 680px;
  transform: translate(-50%, -50%) scale(var(--stage-scale));
}

.stage__halo {
  position: absolute;
  left: -40px;
  top: 80px;
  width: 520px;
  height: 520px;
  border-radius: var(--r-circle);
  background: radial-gradient(circle, var(--c-amber-halo) 0%, var(--c-clear) 66%);
  color: var(--c-on-canvas);
}

.stage__orbit {
  position: absolute;
  border-radius: var(--r-circle);
  transform: rotate(-16deg);
  -webkit-mask-image: linear-gradient(90deg, var(--c-clear) 0%, var(--c-mask) 34%);
  mask-image: linear-gradient(90deg, var(--c-clear) 0%, var(--c-mask) 34%);
}

.stage__orbit--inner {
  left: -50px;
  top: 225px;
  width: 540px;
  height: 230px;
  border: 1px solid var(--c-canvas-line);
}

.stage__orbit--outer {
  left: -60px;
  top: 175px;
  width: 590px;
  height: 330px;
  border: 1px dashed var(--c-canvas-line-soft);
}

.phone {
  position: absolute;
  z-index: 2;
  left: 90px;
  top: 72px;
  width: 260px;
  height: 536px;
  padding: 9px;
  border-radius: var(--r-phone);
  background: linear-gradient(135deg, var(--c-metal-hi) 0%, var(--c-metal) 16%, var(--c-metal-lo) 52%, var(--c-metal) 84%, var(--c-metal-hi) 100%);
  color: var(--c-on-canvas);
  box-shadow: var(--shadow-phone), inset 0 0 0 1px var(--c-glare), inset -2px 2px 0 var(--c-amber-rim);
  transform: rotate(-12deg);
}

.phone__key {
  position: absolute;
  width: 4px;
  border-radius: var(--r-key);
  background: linear-gradient(90deg, var(--c-metal-lo), var(--c-metal-hi) 50%, var(--c-metal));
  color: var(--c-on-canvas);
}

.phone__key--action {
  left: -3px;
  top: 104px;
  height: 26px;
}

.phone__key--vol-up {
  left: -3px;
  top: 150px;
  height: 48px;
}

.phone__key--vol-down {
  left: -3px;
  top: 210px;
  height: 48px;
}

.phone__key--side {
  right: -3px;
  top: 172px;
  height: 78px;
}

.phone__screen {
  position: relative;
  height: 100%;
  overflow: hidden;
  border-radius: var(--r-screen);
  background: linear-gradient(168deg, var(--c-screen-hi) 0%, var(--c-screen-mid) 38%, var(--c-canvas) 84%);
  color: var(--c-on-canvas);
  box-shadow: inset 0 0 0 3px var(--c-glass);
}

.phone__screen::before {
  content: "";
  position: absolute;
  inset: -30%;
  background: radial-gradient(circle at 68% 22%, var(--c-screen-bright) 0%, var(--c-clear) 46%);
  color: var(--c-on-canvas);
  animation: screen-drift 12s ease-in-out infinite alternate;
}

.phone__screen::after {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(118deg, var(--c-glare) 0%, var(--c-clear) 36%);
  color: var(--c-on-canvas);
}

.phone__island {
  position: absolute;
  z-index: 2;
  top: 14px;
  left: 50%;
  width: 82px;
  height: 24px;
  margin-left: -41px;
  border-radius: var(--r-pill);
  background: var(--c-glass);
  color: var(--c-on-canvas);
}

.qa {
  position: absolute;
  animation: qa-rise 0.9s var(--ease-enter) both;
}

.qa--ask {
  z-index: 3;
  left: 244px;
  top: 96px;
  width: 268px;
}

.qa--answer {
  z-index: 5;
  left: 300px;
  top: 268px;
  width: 300px;
  animation-delay: 0.15s;
}

.qa--rule {
  z-index: 4;
  left: 318px;
  top: 512px;
  width: 300px;
  animation-delay: 0.3s;
}

.qa__body {
  position: relative;
  padding: 16px 18px 17px;
  border: 1px solid var(--c-border);
  border-radius: var(--r-card);
  background: var(--c-bg);
  color: var(--c-text);
  box-shadow: var(--shadow-card-near);
  animation: qa-float 8s ease-in-out infinite;
}

.qa--ask .qa__body {
  box-shadow: var(--shadow-card-far);
  animation-duration: 7s;
  animation-delay: -1s;
}

.qa--answer .qa__body {
  animation-duration: 8s;
  animation-delay: -4s;
}

.qa--rule .qa__body {
  animation-duration: 6.5s;
  animation-delay: -2.5s;
}

.qa__head {
  display: flex;
  align-items: center;
  gap: 9px;
  margin-bottom: 9px;
}

.qa__seal {
  display: inline-grid;
  place-items: center;
  width: 26px;
  height: 26px;
  flex-shrink: 0;
  border-radius: var(--r-circle);
  font-family: var(--f-display);
  font-size: var(--fs-xs);
  font-weight: var(--fw-bold);
}

.qa__seal--ask {
  border: 1px solid var(--c-border);
  background: var(--c-panel);
  color: var(--c-muted);
}

.qa__seal--answer {
  background: var(--c-accent);
  color: var(--c-text);
}

.qa__who {
  font-size: 12.5px;
  font-weight: var(--fw-semibold);
  color: var(--c-muted);
}

.qa__src {
  margin-left: auto;
  padding: 2px 8px;
  border-radius: var(--r-pill);
  background: var(--c-panel);
  color: var(--c-accent-dark);
  font-size: 11px;
  font-weight: var(--fw-semibold);
}

.qa__text {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.6;
}

.qa__text .ui {
  font-weight: var(--fw-semibold);
}

.qa__arrow {
  color: var(--c-muted);
}

.qa__body--code {
  padding-left: 24px;
}

.qa__body--code::before {
  content: "";
  position: absolute;
  left: 0;
  top: 16px;
  bottom: 16px;
  width: 3px;
  border-radius: var(--r-key);
  background: var(--c-accent);
  color: var(--c-text);
}

.qa__tag {
  color: var(--c-muted);
  font-family: var(--f-mono);
  font-size: 11.5px;
  font-weight: var(--fw-semibold);
}

.rule {
  margin: 0;
  font-family: var(--f-mono);
  font-size: 12.5px;
  line-height: 1.85;
  letter-spacing: -0.01em;
  white-space: nowrap;
}

.rule__line {
  display: block;
}

.rule__sep,
.rule__val {
  color: var(--c-muted);
}

.rule__policy {
  color: var(--c-accent-dark);
  font-weight: var(--fw-semibold);
}

/* 中轴能力长廊：一条连续线，六块大面板。 */
.feature-gallery {
  position: relative;
  padding-top: 8px;
}

.feature-gallery::before {
  content: "";
  position: absolute;
  top: 8px;
  bottom: 0;
  left: 50%;
  width: 1px;
  background: var(--c-border);
  color: var(--c-text);
}

.gallery-node {
  position: relative;
  z-index: 1;
  display: grid;
  place-items: center;
  width: 48px;
  height: 48px;
  margin: 0 auto 72px;
  border-radius: var(--r-circle);
  background: var(--c-accent);
  color: var(--c-text);
  box-shadow: 0 0 0 8px var(--c-bg);
}

.gallery-node svg {
  width: 20px;
  height: 20px;
}

.gallery-panel {
  position: relative;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  align-items: center;
  gap: 96px;
  min-height: 380px;
  padding: 64px;
  border: 1px solid var(--c-border);
  border-radius: var(--r-canvas);
  background: var(--c-panel);
  color: var(--c-text);
}

.gallery-panel::before {
  content: "";
  position: absolute;
  top: 0;
  bottom: 0;
  left: 50%;
  width: 1px;
  background: var(--c-border);
  color: var(--c-text);
}

.gallery-panel + .gallery-node {
  margin-top: 72px;
}

.gallery-panel:nth-of-type(even) .gallery-panel__copy {
  order: 2;
}

.gallery-panel:nth-of-type(even) .gallery-panel__visual {
  order: 1;
}

.gallery-panel h3 {
  margin: 0 0 24px;
}

.gallery-panel p {
  margin-bottom: 0;
  color: var(--c-muted);
}

.gallery-panel__visual {
  position: relative;
  min-width: 0;
}

.float-note {
  max-width: 100%;
  padding: 24px;
  border: 1px solid var(--c-border);
  border-radius: var(--r-card);
  background: var(--c-bg);
  color: var(--c-text);
  box-shadow: var(--shadow-soft);
}

.float-note + .float-note {
  width: 88%;
  margin-top: 16px;
  margin-left: auto;
}

.float-note pre {
  margin: 12px 0 0;
  padding: 0;
  border: 0;
  border-radius: var(--r-small);
  background: var(--c-bg);
  color: var(--c-text);
}

.float-note .chip-row {
  margin: 12px 0 0;
}

/* 可访问的 tabs；无脚本时各正文仍然可读。 */
.tabs {
  min-width: 0;
}

.tabs [role="tablist"] {
  display: flex;
  align-items: center;
  gap: 8px;
  max-width: 100%;
  overflow-x: auto;
  padding: 6px;
  margin-bottom: 24px;
  border: 1px solid var(--c-border);
  border-radius: var(--r-pill);
  background: var(--c-panel);
  color: var(--c-text);
  overscroll-behavior-x: contain;
}

.tabs [role="tab"] {
  flex-shrink: 0;
  min-height: 44px;
  padding: 10px 22px;
  border: 0;
  border-radius: var(--r-pill);
  background: var(--c-clear);
  color: var(--c-muted);
  font-weight: var(--fw-semibold);
}

.tabs [role="tab"]:hover {
  background: var(--c-bg);
  color: var(--c-text);
}

.tabs [role="tab"][aria-selected="true"] {
  background: var(--c-accent);
  color: var(--c-text);
}

.tabs [role="tabpanel"] {
  min-width: 0;
}

.tabs [role="tabpanel"] + [role="tabpanel"] {
  margin-top: 24px;
}

/* toc 必须直接处在覆盖所有章节的长内容父容器中。 */
.toc {
  position: sticky;
  top: calc(var(--head-h) + 12px);
  z-index: 10;
  margin-bottom: 40px;
  padding: 12px;
  border: 1px solid var(--c-border);
  border-radius: var(--r-card);
  background: var(--c-bg);
  color: var(--c-text);
  box-shadow: var(--shadow-soft);
}

.toc ul {
  display: flex;
  align-items: center;
  gap: 8px;
  overflow-x: auto;
  padding: 0;
  margin: 0;
  list-style: none;
  overscroll-behavior-x: contain;
}

.toc li {
  flex-shrink: 0;
}

.toc a {
  display: block;
  min-height: 44px;
  padding: 10px 16px;
  border-radius: var(--r-pill);
  font-size: var(--fs-sm);
}

.toc a:hover,
.toc a[aria-current="location"] {
  background: var(--c-panel);
  color: var(--c-accent-dark);
}

.toc--flow {
  position: static;
}

.faq-item {
  border-bottom: 1px solid var(--c-border);
}

.faq-item summary {
  position: relative;
  list-style: none;
  min-height: 64px;
  padding: 20px 48px 20px 0;
  cursor: pointer;
  font-weight: var(--fw-semibold);
}

.faq-item summary::-webkit-details-marker {
  display: none;
}

.faq-item summary::after {
  content: "+";
  position: absolute;
  top: 18px;
  right: 8px;
  display: grid;
  place-items: center;
  width: 28px;
  height: 28px;
  border-radius: var(--r-circle);
  background: var(--c-panel);
  color: var(--c-text);
}

.faq-item[open] summary::after {
  content: "−";
  background: var(--c-accent);
  color: var(--c-text);
}

.faq-item__answer {
  max-width: 760px;
  padding-bottom: 20px;
  color: var(--c-muted);
}

.faq-item__answer > :last-child {
  margin-bottom: 0;
}

.term-card {
  padding: 28px;
  border: 1px solid var(--c-border);
  border-radius: var(--r-card);
  background: var(--c-bg);
  color: var(--c-text);
}

.term-card__word {
  margin: 0 0 12px;
  font-family: var(--f-mono);
  font-size: var(--fs-lead);
  overflow-wrap: anywhere;
}

.term-card__category,
.article-card__tag {
  display: inline-block;
  max-width: 100%;
  margin-bottom: 16px;
  color: var(--c-accent-dark);
  font-size: var(--fs-xs);
  font-weight: var(--fw-semibold);
  overflow-wrap: anywhere;
}

.term-card p {
  margin-bottom: 0;
  color: var(--c-muted);
}

.store-button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 12px;
  min-height: 56px;
  max-width: 100%;
  padding: 10px 24px;
  border: 1px solid var(--c-clear);
  border-radius: var(--r-pill);
  background: var(--c-accent);
  color: var(--c-text);
  box-shadow: var(--shadow-cta);
  text-align: left;
  transition: transform var(--t-fast) ease;
}

.store-button > svg {
  width: 24px;
  height: 28px;
}

.store-button__words {
  display: flex;
  flex-direction: column;
  min-width: 0;
  line-height: 1.25;
}

.store-button__top {
  font-size: 11px;
  font-weight: var(--fw-medium);
}

.store-button__bottom {
  font-size: var(--fs-body);
  font-weight: var(--fw-bold);
}

.store-button:hover {
  transform: translateY(-2px);
}

.store-button:active {
  transform: none;
}

.official-shot {
  width: 100%;
  max-width: 280px;
  min-width: 0;
  margin: 0 auto;
  flex-shrink: 0;
}

.official-shot img {
  display: block;
  width: 100%;
  height: auto;
  border-radius: var(--r-shot);
}

.official-shot img,
.shot-placeholder {
  outline: 1px solid var(--c-border);
  outline-offset: -1px;
}

.official-shot figcaption {
  margin-top: 12px;
  color: var(--c-muted);
  font-size: var(--fs-xs);
  line-height: 1.6;
}

.shot-row {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 32px;
}

.device-card {
  display: flex;
  align-items: flex-start;
  gap: 24px;
  padding: 32px;
  border: 1px solid var(--c-border);
  border-radius: var(--r-canvas);
  background: var(--c-panel);
  color: var(--c-text);
}

.device-card__icon {
  width: 48px;
  height: 56px;
  color: var(--c-text);
}

.device-card > div {
  min-width: 0;
}

.device-card h3 {
  margin: 0 0 12px;
}

.device-card p {
  color: var(--c-muted);
}

.device-card .text-link {
  display: inline-flex;
  align-items: center;
  min-height: 44px;
}

.article-card {
  display: flex;
  flex-direction: column;
  min-width: 0;
  padding: 28px;
  border: 1px solid var(--c-border);
  border-radius: var(--r-card);
  background: var(--c-bg);
  color: var(--c-text);
  box-shadow: var(--shadow-soft);
}

.article-card h3 {
  margin: 0 0 16px;
  font-size: var(--fs-lead);
}

.article-card h3 a:hover {
  text-decoration: underline;
  text-underline-offset: 0.18em;
}

.article-card p {
  color: var(--c-muted);
}

.article-card__link {
  align-self: flex-start;
  margin-top: auto;
  color: var(--c-accent-dark);
  font-weight: var(--fw-semibold);
  min-height: 44px;
  padding-top: 10px;
}

.callout {
  margin: 24px 0;
  padding: 24px 28px;
  border: 1px solid var(--c-border);
  border-left: 4px solid var(--c-accent-dark);
  border-radius: var(--r-card);
  background: var(--c-panel);
  color: var(--c-text);
}

.callout > :last-child {
  margin-bottom: 0;
}

.callout--warn {
  border-left-color: var(--c-warn);
}

.callout--success {
  border-left-color: var(--c-success);
}

.group-list {
  list-style: none;
  margin: 0;
  padding: 0;
  border: 1px solid var(--c-border);
  border-radius: var(--r-card);
  background: var(--c-bg);
  color: var(--c-text);
}

.group-list li + li {
  border-top: 1px solid var(--c-border);
}

.group-list a {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
  min-height: 60px;
  padding: 16px 24px;
}

.group-list a::after {
  content: "›";
  color: var(--c-muted);
  flex-shrink: 0;
}

.group-list a:hover {
  color: var(--c-accent-dark);
}

.table-scroll {
  min-width: 0;
  max-width: 100%;
  overflow-x: auto;
  overscroll-behavior-x: contain;
  -webkit-overflow-scrolling: touch;
  border: 1px solid var(--c-border);
  border-radius: var(--r-card);
}

.data-table {
  width: 100%;
  border-collapse: collapse;
  background: var(--c-bg);
  color: var(--c-text);
  text-align: left;
}

.data-table th,
.data-table td,
.prose table th,
.prose table td,
.article-body table th,
.article-body table td {
  min-width: 7em;
  padding: 16px 20px;
  border-bottom: 1px solid var(--c-border);
  white-space: normal;
  overflow-wrap: normal;
  word-break: normal;
  vertical-align: top;
}

.data-table th,
.prose table th,
.article-body table th {
  background: var(--c-panel);
  color: var(--c-text);
  font-weight: var(--fw-semibold);
}

.data-table tr:last-child td {
  border-bottom: 0;
}

/* 后代选择器也覆盖隔着 div 的裸表格。 */
.prose table,
.article-body table {
  display: block;
  width: 100%;
  max-width: 100%;
  min-width: 0;
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
  overscroll-behavior-x: contain;
  border-collapse: collapse;
  background: var(--c-bg);
  color: var(--c-text);
}

.article-store-card {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  align-items: center;
  gap: 24px;
  padding: 32px;
  margin-top: 48px;
  border: 1px solid var(--c-border);
  border-radius: var(--r-canvas);
  background: var(--c-panel);
  color: var(--c-text);
}

.article-store-card > * {
  min-width: 0;
}

.article-store-card h2 {
  margin: 0 0 12px;
  font-size: var(--fs-h3);
}

.article-store-card p {
  margin: 0;
  color: var(--c-muted);
}

.dl-fab {
  position: fixed;
  right: 24px;
  bottom: calc(24px + env(safe-area-inset-bottom, 0px));
  z-index: 30;
  display: inline-flex;
  align-items: center;
  gap: 10px;
  min-height: 52px;
  max-width: calc(100% - 32px);
  padding: 12px 22px 12px 18px;
  border-radius: var(--r-pill);
  background: var(--c-accent);
  color: var(--c-text);
  font-size: 15px;
  font-weight: var(--fw-semibold);
  line-height: 1.3;
  box-shadow: var(--shadow-fab);
  transition: transform var(--t-fast) ease;
}

.dl-fab svg {
  width: 17px;
  height: 17px;
}

.dl-fab:hover {
  transform: translateY(-2px);
}

/* 预览专用家具，仍共享同一套令牌。 */
.preview-only .qa,
.preview-only .qa__body,
.preview-only .phone__screen::before {
  animation: none;
}

.preview-only .toc {
  position: static;
}

.preview-samples {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 16px;
}

.preview-dark {
  padding: 24px;
  border-radius: var(--r-card);
  background: var(--c-canvas);
  color: var(--c-on-canvas);
}

.preview-swatch-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 16px;
}

.swatch {
  min-width: 0;
  margin: 0;
  border: 1px solid var(--c-border);
  border-radius: var(--r-card);
  background: var(--c-bg);
  color: var(--c-text);
}

.swatch__paint {
  height: 72px;
  border-radius: var(--r-card) var(--r-card) 0 0;
}

.swatch figcaption {
  padding: 12px 16px;
  font-family: var(--f-mono);
  font-size: var(--fs-xs);
  overflow-wrap: anywhere;
}

.swatch--bg .swatch__paint { background: var(--c-bg); color: var(--c-text); }
.swatch--panel .swatch__paint { background: var(--c-panel); color: var(--c-text); }
.swatch--canvas .swatch__paint { background: var(--c-canvas); color: var(--c-on-canvas); }
.swatch--border .swatch__paint { background: var(--c-border); color: var(--c-text); }
.swatch--accent .swatch__paint { background: var(--c-accent); color: var(--c-text); }
.swatch--accent-dark .swatch__paint { background: var(--c-accent-dark); color: var(--c-on-canvas); }
.swatch--text .swatch__paint { background: var(--c-text); color: var(--c-bg); }
.swatch--muted .swatch__paint { background: var(--c-muted); color: var(--c-bg); }
.swatch--success .swatch__paint { background: var(--c-success); color: var(--c-bg); }
.swatch--warn .swatch__paint { background: var(--c-warn); color: var(--c-text); }
.swatch--error .swatch__paint { background: var(--c-error); color: var(--c-bg); }
.swatch--on-canvas .swatch__paint { background: var(--c-on-canvas); color: var(--c-text); }
.swatch--amber .swatch__paint { background: var(--c-canvas); background-image: radial-gradient(ellipse at top right, var(--c-amber-core), var(--c-amber-mid), var(--c-clear)); color: var(--c-on-canvas); }
.swatch--metal .swatch__paint { background: linear-gradient(135deg, var(--c-metal-hi), var(--c-metal), var(--c-metal-lo)); color: var(--c-on-canvas); }
.swatch--screen .swatch__paint { background: linear-gradient(168deg, var(--c-screen-hi), var(--c-screen-mid), var(--c-canvas)); color: var(--c-on-canvas); }
.swatch--glow .swatch__paint { background: var(--c-canvas); background-image: radial-gradient(circle, var(--c-accent-glow), var(--c-clear)); color: var(--c-on-canvas); }

.shot-placeholder {
  display: grid;
  place-items: center;
  width: 100%;
  aspect-ratio: 750 / 1334;
  padding: 24px;
  border-radius: var(--r-shot);
  background: var(--c-panel);
  color: var(--c-muted);
  text-align: center;
  font-size: var(--fs-sm);
}

.preview-type h2:first-child {
  margin-top: 0;
}

@keyframes qa-rise {
  from {
    opacity: 0;
    transform: translate3d(0, 18px, 0);
  }
  to {
    opacity: 1;
    transform: none;
  }
}

@keyframes qa-float {
  0%, 100% {
    transform: translate3d(0, -4px, 0);
  }
  50% {
    transform: translate3d(0, 4px, 0);
  }
}

@keyframes screen-drift {
  from {
    transform: translate3d(-6%, -4%, 0);
  }
  to {
    transform: translate3d(6%, 5%, 0);
  }
}

@media (max-width: 960px) {
  :root {
    --stage-scale: 0.64;
  }

  .hero__canvas {
    height: auto;
    grid-template-columns: minmax(0, 1fr);
    padding: 44px 28px 12px;
    row-gap: 8px;
  }

  .hero__title {
    font-size: 30px;
  }

  .stage {
    height: calc(680px * var(--stage-scale));
  }

  .qa--rule {
    display: none;
  }

  .gallery-panel {
    gap: 48px;
    padding: 40px;
  }
}

@media (max-width: 768px) {
  .gallery-panel {
    gap: 32px;
  }

  .preview-swatch-grid {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

  .article-store-card {
    grid-template-columns: minmax(0, 1fr);
  }
}

@media (max-width: 640px) {
  .feature-gallery {
    padding-left: 40px;
  }

  .feature-gallery::before {
    left: 20px;
  }

  .gallery-node {
    width: 36px;
    height: 36px;
    margin-left: -38px;
    margin-right: 0;
    margin-bottom: 48px;
  }

  .gallery-panel {
    min-height: 0;
    grid-template-columns: minmax(0, 1fr);
    padding: 28px 22px;
    gap: 32px;
  }

  .gallery-panel::before {
    display: none;
  }

  .gallery-panel:nth-of-type(even) .gallery-panel__copy,
  .gallery-panel:nth-of-type(even) .gallery-panel__visual {
    order: initial;
  }

  .gallery-panel + .gallery-node {
    margin-top: 48px;
  }

  .float-note {
    padding: 18px;
  }

  .device-card {
    padding: 24px;
    gap: 18px;
  }

  .device-card__icon {
    width: 36px;
    height: 44px;
  }

  .shot-row {
    flex-direction: column;
    align-items: center;
  }

  .chip-row,
  .fact-row {
    flex-direction: row;
    flex-wrap: wrap;
  }

  .callout,
  .term-card,
  .article-card,
  .article-store-card {
    padding: 24px;
  }

  .preview-swatch-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .dl-fab {
    right: 16px;
    bottom: calc(16px + env(safe-area-inset-bottom, 0px));
    min-height: 46px;
    font-size: var(--fs-sm);
  }
}

@media (max-width: 560px) {
  :root {
    --edge: 12px;
    --stage-scale: 0.5;
  }

  .hero__canvas {
    border-radius: var(--r-mobile-canvas);
    padding: 36px 20px 8px;
  }

  .hero__title {
    font-size: clamp(25px, 7vw, 30px);
  }

  .hero__actions .btn {
    flex: 1 1 auto;
  }

  .device-row {
    gap: 10px 16px;
  }
}

@media (max-width: 360px) {
  :root {
    --stage-scale: 0.43;
  }

  .hero__canvas {
    padding-inline: 16px;
  }

  .hero__title {
    font-size: 25px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .qa,
  .qa__body,
  .phone__screen::before {
    animation: none;
  }

  .dl-fab:hover,
  .store-button:hover {
    transform: none;
  }
}