:root {
  color-scheme: light;
  --ink: #17202a;
  --muted: #5d6978;
  --line: #dce4ea;
  --paper: #f8faf9;
  --surface: #ffffff;
  --green: #1d8a57;
  --green-dark: #0d5f3b;
  --blue: #2d73b9;
  --amber: #d98d24;
  --coral: #c45546;
  --shadow: 0 18px 50px rgba(23, 32, 42, 0.11);
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family:
    -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC",
    "Hiragino Sans GB", "Microsoft YaHei", Arial, sans-serif;
  color: var(--ink);
  background: var(--paper);
  line-height: 1.65;
}

a {
  color: inherit;
  text-decoration: none;
}

img {
  display: block;
  max-width: 100%;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 20;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  min-height: 72px;
  padding: 12px clamp(18px, 5vw, 72px);
  background: rgba(248, 250, 249, 0.85);
  border-bottom: 1px solid rgba(220, 228, 234, 0.9);
  -webkit-backdrop-filter: blur(18px);
  backdrop-filter: blur(18px);
  -webkit-backface-visibility: hidden;
  backface-visibility: hidden;
  will-change: backdrop-filter;
  isolation: isolate;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  min-width: max-content;
  font-weight: 800;
  letter-spacing: 0;
}

.brand img {
  width: 38px;
  height: 38px;
  border-radius: 8px;
}

.nav-links {
  display: flex;
  align-items: center;
  justify-content: flex-end;
  gap: clamp(12px, 3vw, 34px);
  color: var(--muted);
  font-size: 15px;
  white-space: nowrap;
}

.nav-links a:hover,
.nav-links a:focus-visible {
  color: var(--green-dark);
}

.hero {
  display: grid;
  grid-template-columns: minmax(0, 1.05fr) minmax(300px, 0.75fr);
  align-items: center;
  gap: clamp(32px, 7vw, 92px);
  min-height: calc(100vh - 72px);
  padding: clamp(36px, 6vw, 82px) clamp(20px, 6vw, 88px) clamp(42px, 7vw, 96px);
  background:
    linear-gradient(115deg, rgba(255, 255, 255, 0.88), rgba(242, 248, 245, 0.92)),
    url("./assets/hero-system.png") center / cover;
  overflow: hidden;
}

.hero-copy {
  max-width: 770px;
}

.eyebrow {
  margin: 0 0 12px;
  color: var(--green-dark);
  font-size: 13px;
  font-weight: 800;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

h1,
h2,
h3,
p {
  overflow-wrap: anywhere;
}

h1 {
  margin: 0;
  font-size: clamp(56px, 10vw, 124px);
  line-height: 0.95;
  letter-spacing: 0;
}

h2 {
  margin: 0;
  font-size: clamp(28px, 5vw, 52px);
  line-height: 1.12;
  letter-spacing: 0;
}

h3 {
  margin: 0;
  font-size: 22px;
  line-height: 1.25;
  letter-spacing: 0;
}

.hero-lead {
  max-width: 690px;
  margin: 28px 0 0;
  color: #3d4956;
  font-size: clamp(18px, 2.3vw, 24px);
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 14px;
  margin-top: 34px;
}

.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 48px;
  padding: 0 20px;
  border: 1px solid transparent;
  border-radius: 8px;
  font-weight: 800;
  line-height: 1.1;
  transition:
    transform 160ms ease,
    box-shadow 160ms ease,
    background 160ms ease;
}

.button:hover,
.button:focus-visible {
  transform: translateY(-1px);
}

.button.primary {
  color: #ffffff;
  background: var(--green);
  box-shadow: 0 14px 28px rgba(29, 138, 87, 0.22);
}

.button.primary:hover,
.button.primary:focus-visible {
  background: var(--green-dark);
}

.button.secondary {
  color: var(--ink);
  background: rgba(255, 255, 255, 0.78);
  border-color: var(--line);
}

.hero-media {
  width: min(100%, 560px);
  margin: 0;
  justify-self: center;
  border: 1px solid rgba(255, 255, 255, 0.72);
  border-radius: 8px;
  box-shadow: var(--shadow);
  overflow: hidden;
}

.hero-media img {
  width: 100%;
  aspect-ratio: 1586 / 992;
  object-fit: cover;
}

.section {
  padding: clamp(58px, 8vw, 104px) clamp(20px, 6vw, 88px);
}

.section[id] {
  scroll-margin-top: 88px;
}

.section-heading {
  max-width: 920px;
}

.section-heading p:not(.eyebrow) {
  margin: 20px 0 0;
  color: var(--muted);
  font-size: 18px;
}

.flow {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 18px;
  margin-top: 34px;
}

.flow-step,
.module-card,
.download-panel,
.notice article {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 8px;
  box-shadow: 0 10px 32px rgba(23, 32, 42, 0.06);
}

.flow-step {
  min-height: 230px;
  padding: 26px;
}

.step-index {
  display: inline-flex;
  margin-bottom: 48px;
  color: var(--blue);
  font-size: 14px;
  font-weight: 900;
}

.flow-step p,
.module-card p,
.notice p,
.detail-band p,
.download p {
  color: var(--muted);
}

.modules {
  background: #ffffff;
}

.module-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 22px;
  margin-top: 34px;
}

.module-card {
  padding: clamp(26px, 4vw, 38px);
}

.module-card.accent {
  border-top: 5px solid var(--amber);
}

.module-card:not(.accent) {
  border-top: 5px solid var(--blue);
}

.module-kicker {
  margin: 0 0 10px;
  color: var(--green-dark);
  font-family: "SFMono-Regular", Consolas, "Liberation Mono", monospace;
  font-size: 14px;
  font-weight: 800;
}

.module-card > p:not(.module-kicker) {
  margin: 16px 0 24px;
}

.product-gallery {
  background:
    radial-gradient(circle at 85% 8%, rgba(29, 138, 87, 0.11), transparent 28%),
    #eef3f0;
}

.product-gallery .section-heading {
  max-width: 820px;
}

.product-gallery-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 22px;
  margin-top: 36px;
}

.product-shot {
  margin: 0;
  background: var(--surface);
  border: 1px solid rgba(205, 216, 211, 0.92);
  border-radius: 10px;
  box-shadow: 0 16px 44px rgba(23, 32, 42, 0.08);
  overflow: hidden;
  transition: transform .28s ease, box-shadow .28s ease;
}

.product-shot-wide {
  grid-column: 1 / -1;
}

.product-shot:hover {
  transform: translateY(-4px);
  box-shadow: 0 24px 56px rgba(15, 30, 40, 0.13);
}

.product-shot-media {
  aspect-ratio: 4 / 3;
  background: #ffffff;
  overflow: hidden;
}

.product-shot-wide .product-shot-media {
  aspect-ratio: 1880 / 837;
}

.product-shot img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform .55s ease;
}

.product-shot:hover img {
  transform: scale(1.018);
}

.product-shot figcaption {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 18px;
  padding: 18px 20px 19px;
  border-top: 1px solid #edf1ef;
}

.product-shot figcaption span {
  color: var(--green-dark);
  font-family: "SFMono-Regular", Consolas, "Liberation Mono", monospace;
  font-size: 12px;
  font-weight: 800;
  letter-spacing: .06em;
  text-transform: uppercase;
}

.product-shot figcaption strong {
  font-size: 17px;
}

dl {
  display: grid;
  gap: 12px;
  margin: 0;
}

dl div {
  display: grid;
  grid-template-columns: 88px minmax(0, 1fr);
  gap: 14px;
  padding-top: 12px;
  border-top: 1px solid var(--line);
}

dt {
  color: #667382;
  font-weight: 800;
}

dd {
  margin: 0;
}

.detail-band {
  display: grid;
  grid-template-columns: minmax(0, 0.85fr) minmax(280px, 0.65fr);
  gap: 34px;
  align-items: start;
  color: #ffffff;
  background: #173b3a;
}

.model-showcase {
  display: grid;
  grid-template-columns: minmax(280px, 0.72fr) minmax(480px, 1.28fr);
  gap: clamp(34px, 6vw, 84px);
  align-items: center;
  background:
    radial-gradient(circle at 78% 16%, rgba(45, 115, 185, 0.12), transparent 31%),
    linear-gradient(145deg, #f4f8f6 0%, #e7efeb 100%);
}

.model-showcase-copy > p:not(.eyebrow) {
  margin: 20px 0 0;
  color: var(--muted);
  font-size: 18px;
}

.model-spec-list {
  display: grid;
  gap: 10px;
  margin: 30px 0 0;
  padding: 0;
  list-style: none;
}

.model-spec-list li {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 18px;
  padding: 13px 0;
  border-bottom: 1px solid rgba(119, 142, 131, 0.28);
}

.model-spec-list span {
  color: var(--green-dark);
  font-family: "SFMono-Regular", Consolas, "Liberation Mono", monospace;
  font-size: 13px;
  font-weight: 800;
}

.model-spec-list strong {
  text-align: right;
}

.model-viewer-card {
  min-width: 0;
  background: rgba(255, 255, 255, 0.82);
  border: 1px solid rgba(188, 205, 197, 0.95);
  border-radius: 14px;
  box-shadow: 0 26px 64px rgba(24, 49, 39, 0.14);
  overflow: hidden;
}

.model-stage {
  position: relative;
  min-height: 460px;
  aspect-ratio: 16 / 10;
  background:
    radial-gradient(circle at 50% 42%, rgba(255, 255, 255, 0.98), rgba(228, 237, 232, 0.9) 62%, rgba(206, 220, 213, 0.94));
  overflow: hidden;
  touch-action: none;
  cursor: grab;
}

.model-stage:active {
  cursor: grabbing;
}

.model-fallback,
.model-canvas {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
}

.model-fallback {
  padding: clamp(28px, 6vw, 70px);
  object-fit: contain;
  opacity: 1;
  transition: opacity .35s ease;
}

.model-canvas {
  opacity: 0;
  outline: none;
  transition: opacity .35s ease;
}

.model-viewer-card[data-state="ready"] .model-fallback {
  opacity: 0;
  pointer-events: none;
}

.model-viewer-card[data-state="ready"] .model-canvas {
  opacity: 1;
}

.model-loading {
  position: absolute;
  top: 18px;
  left: 18px;
  display: inline-flex;
  align-items: center;
  gap: 9px;
  padding: 9px 12px;
  color: #405047;
  background: rgba(255, 255, 255, 0.78);
  border: 1px solid rgba(185, 202, 193, 0.9);
  border-radius: 999px;
  font-size: 13px;
  font-weight: 800;
  -webkit-backdrop-filter: blur(12px);
  backdrop-filter: blur(12px);
  transition: opacity .25s ease;
}

.model-viewer-card[data-state="ready"] .model-loading,
.model-viewer-card[data-state="error"] .model-loading {
  opacity: 0;
  pointer-events: none;
}

.model-spinner {
  width: 13px;
  height: 13px;
  border: 2px solid rgba(29, 138, 87, 0.22);
  border-top-color: var(--green);
  border-radius: 50%;
  animation: modelSpin .8s linear infinite;
}

.model-instruction {
  position: absolute;
  right: 16px;
  bottom: 14px;
  margin: 0;
  padding: 8px 11px;
  color: #425149;
  background: rgba(255, 255, 255, 0.72);
  border: 1px solid rgba(185, 202, 193, 0.82);
  border-radius: 999px;
  font-size: 12px;
  font-weight: 800;
  pointer-events: none;
  -webkit-backdrop-filter: blur(10px);
  backdrop-filter: blur(10px);
}

.model-toolbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 18px;
  padding: 16px 18px;
  border-top: 1px solid rgba(205, 218, 211, 0.86);
}

.model-status {
  display: inline-flex;
  align-items: center;
  gap: 9px;
  margin: 0;
  color: #506057;
  font-size: 13px;
  font-weight: 700;
}

.model-status-dot {
  width: 9px;
  height: 9px;
  flex: 0 0 auto;
  background: var(--amber);
  border-radius: 50%;
  box-shadow: 0 0 0 5px rgba(217, 141, 36, 0.12);
}

.model-viewer-card[data-state="ready"] .model-status-dot {
  background: var(--green);
  box-shadow: 0 0 0 5px rgba(29, 138, 87, 0.12);
}

.model-viewer-card[data-state="error"] .model-status-dot {
  background: var(--coral);
  box-shadow: 0 0 0 5px rgba(196, 85, 70, 0.12);
}

.model-controls {
  display: flex;
  gap: 8px;
}

.model-control {
  min-height: 38px;
  padding: 0 13px;
  color: var(--green-dark);
  background: #ffffff;
  border: 1px solid #cddbd4;
  border-radius: 7px;
  font: inherit;
  font-size: 13px;
  font-weight: 800;
  cursor: pointer;
  transition: transform .16s ease, border-color .16s ease, box-shadow .16s ease;
}

.model-control:hover,
.model-control:focus-visible {
  border-color: var(--green);
  box-shadow: 0 8px 18px rgba(29, 138, 87, 0.13);
  transform: translateY(-1px);
}

@keyframes modelSpin {
  to { transform: rotate(360deg); }
}

.detail-band h2,
.detail-band p {
  color: #ffffff;
}

.feature-list {
  display: grid;
  gap: 14px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.feature-list li {
  padding: 16px 18px;
  color: #f8fbfb;
  background: rgba(255, 255, 255, 0.09);
  border: 1px solid rgba(255, 255, 255, 0.2);
  border-radius: 8px;
}

.download {
  display: grid;
  grid-template-columns: minmax(0, 0.9fr) minmax(320px, 0.55fr);
  gap: 30px;
  align-items: center;
  background: #f2f6f8;
}

.download-copy {
  max-width: 760px;
}

.download-panel {
  display: grid;
  gap: 14px;
  padding: 28px;
}

.download-panel > div {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 16px;
  padding-bottom: 12px;
  border-bottom: 1px solid var(--line);
}

.label {
  color: #687685;
  font-weight: 800;
}

.download-button {
  width: 100%;
  margin-top: 8px;
}

.notice-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 18px;
  margin-top: 32px;
}

.notice article {
  min-height: 240px;
  padding: 26px;
}

.practices-hero {
  padding-top: clamp(34px, 5vw, 72px);
}

.my-project-band {
  padding-top: clamp(34px, 5vw, 64px);
  padding-bottom: clamp(34px, 5vw, 64px);
  background: #f2f6f8;
}

.my-project-band .section-heading {
  max-width: 920px;
}

.practices-hero h1 {
  font-size: clamp(44px, 8vw, 88px);
  line-height: 1.02;
}

.practices-hero .section-heading {
  max-width: 980px;
}

.practices-hero .section-heading p:not(.eyebrow) {
  max-width: 820px;
}

.practices-actions {
  margin-top: 28px;
}

.practices-list-section {
  background: #ffffff;
}

.practice-link-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 22px;
  margin-top: 34px;
}

.practice-link-card {
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  gap: 20px;
  padding: clamp(22px, 3vw, 34px);
  background: #fafcfb;
  border: 1px solid var(--line);
  border-left: 4px solid var(--green);
  border-radius: 0 10px 10px 0;
  transition: border-color .25s ease, background .25s ease, transform .2s ease;
}

.practice-link-card:nth-child(2),
.practice-link-card:nth-child(4) {
  border-left-color: var(--blue);
}

.practice-link-card:hover,
.practice-link-card:focus-within {
  background: #ffffff;
  border-color: var(--green);
  transform: translateX(6px);
}

.practice-link-card:nth-child(2):hover,
.practice-link-card:nth-child(4):hover {
  border-color: var(--blue);
}

.practice-link-card p:not(.module-kicker) {
  margin: 8px 0 0;
  color: var(--muted);
  font-size: 15px;
  line-height: 1.6;
}

.practice-link-card .module-kicker {
  font-size: 12px;
  margin-bottom: 6px;
}

.practice-link-card h3 {
  font-size: 20px;
}

.practice-link-card dl {
  gap: 8px;
}

.practice-link-card dl div {
  grid-template-columns: 64px minmax(0, 1fr);
  gap: 10px;
  padding-top: 8px;
}

.practice-link-card a {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  color: var(--green-dark);
  font-weight: 700;
  font-size: 14px;
  text-decoration: none;
  transition: color .2s ease;
}

.practice-link-card a::after {
  content: " →";
  transition: transform .2s ease;
}

.practice-link-card a:hover,
.practice-link-card a:focus-visible {
  color: var(--blue);
}

.practice-link-card a:hover::after {
  transform: translateX(3px);
}

.card-cover {
  width: 100%;
  max-height: 200px;
  object-fit: contain;
  object-position: center top;
  border-radius: 6px;
  margin-bottom: 12px;
  background: #eef1f2;
}

.practices-compliance {
  background: #173b3a;
}

.science-resource-band {
  color: #f8eee6;
  background:
    radial-gradient(circle at 82% 12%, rgba(255, 113, 22, 0.18), transparent 30%),
    #171613;
}

.science-resource-grid {
  display: grid;
  grid-template-columns: minmax(0, 1.2fr) minmax(320px, 0.8fr);
  align-items: center;
  gap: clamp(30px, 6vw, 76px);
  max-width: 1420px;
  margin: 0 auto;
}

.science-resource-cover {
  position: relative;
  display: block;
  border: 1px solid rgba(255, 255, 255, 0.18);
  border-radius: 12px;
  box-shadow: 0 28px 70px rgba(0, 0, 0, 0.36);
  overflow: hidden;
  transition: transform .25s ease, border-color .25s ease;
}

.science-resource-cover:hover,
.science-resource-cover:focus-visible {
  border-color: #ff7116;
  transform: translateY(-5px);
}

.science-resource-cover img {
  width: 100%;
  height: auto;
  aspect-ratio: 16 / 9;
  object-fit: cover;
}

.science-resource-cover span {
  position: absolute;
  right: 16px;
  bottom: 16px;
  padding: 9px 13px;
  color: #171613;
  background: #fff4eb;
  border-radius: 7px;
  font-size: 14px;
  font-weight: 900;
}

.science-resource-copy h2,
.science-resource-copy h3 {
  color: #fff8f1;
}

.science-resource-copy h3 {
  max-width: 580px;
  margin-top: 22px;
  font-size: clamp(22px, 3vw, 34px);
}

.science-resource-copy > p:not(.eyebrow) {
  margin: 14px 0 0;
  color: #c8c1ba;
  font-size: 17px;
}

.science-primary {
  color: #171613;
  background: #ff7116;
  box-shadow: 0 14px 30px rgba(255, 113, 22, 0.24);
}

.science-primary:hover,
.science-primary:focus-visible {
  background: #ff8b42;
}

.science-secondary {
  color: inherit;
  background: rgba(255, 255, 255, 0.08);
  border-color: rgba(255, 255, 255, 0.26);
}

.science-secondary:hover,
.science-secondary:focus-visible {
  color: #171613;
  background: #fff4eb;
}

.volunteer-counter {
  padding: clamp(24px, 4vw, 38px);
  color: #fff8f1;
  background: rgba(255, 255, 255, 0.07);
  border: 1px solid rgba(255, 255, 255, 0.18);
  border-radius: 12px;
  box-shadow: 0 22px 60px rgba(0, 0, 0, 0.22);
}

.volunteer-counter.compact {
  margin-top: 26px;
  padding: 22px;
  box-shadow: none;
}

.volunteer-label {
  display: block;
  color: #ff9b5c;
  font-size: 13px;
  font-weight: 900;
  letter-spacing: .08em;
  text-transform: uppercase;
}

.volunteer-count {
  margin: 12px 0 0;
  color: #fff8f1;
  font-size: clamp(18px, 2.4vw, 28px);
  font-weight: 800;
}

.volunteer-count > span,
.volunteer-count > strong {
  display: block;
}

.volunteer-count strong {
  margin: 10px 0 5px;
  color: #ff7116;
  font-size: clamp(38px, 4.5vw, 60px);
  line-height: 1;
  letter-spacing: -.04em;
  white-space: nowrap;
}

.compact .volunteer-count strong {
  font-size: clamp(34px, 4vw, 50px);
}

.counter-status {
  margin: 12px 0 0;
  color: #d9d0c8;
}

.counter-status.is-error {
  color: #ffc7a3;
}

.volunteer-counter small {
  display: block;
  margin-top: 16px;
  color: #a9a39d;
}

.visitor-counter-probe {
  display: none !important;
}

.science-page-hero {
  display: grid;
  grid-template-columns: minmax(0, 1.25fr) minmax(320px, .75fr);
  align-items: center;
  gap: clamp(34px, 7vw, 92px);
  min-height: 620px;
  color: #fff8f1;
  background:
    radial-gradient(circle at 80% 20%, rgba(255, 113, 22, .23), transparent 34%),
    linear-gradient(130deg, #171613 0%, #23211e 60%, #171613 100%);
}

.science-page-copy {
  max-width: 880px;
}

.science-page-copy h1 {
  max-width: 880px;
  color: #fff8f1;
  font-size: clamp(42px, 7vw, 82px);
  line-height: 1.04;
}

.science-page-copy > p:not(.eyebrow) {
  max-width: 780px;
  margin: 24px 0 0;
  color: #cbc4bd;
  font-size: clamp(17px, 2vw, 21px);
}

.science-deck-section {
  background: #ffffff;
}

.science-deck-player {
  max-width: 1420px;
  margin: 36px auto 0;
  background: #11100e;
  border: 1px solid #2f2c29;
  border-radius: 12px;
  box-shadow: 0 28px 70px rgba(17, 16, 14, .2);
  overflow: hidden;
  outline: none;
}

.science-deck-player:focus-visible {
  box-shadow: 0 0 0 4px rgba(255, 113, 22, .3), 0 28px 70px rgba(17, 16, 14, .2);
}

.deck-stage {
  position: relative;
  display: grid;
  place-items: center;
  min-height: 280px;
  background: #090909;
}

.deck-stage::after {
  content: "正在加载…";
  position: absolute;
  inset: 0;
  display: grid;
  place-items: center;
  color: #d4cbc3;
  background: rgba(9, 9, 9, .78);
  opacity: 0;
  pointer-events: none;
  transition: opacity .15s ease;
}

.science-deck-player.is-loading .deck-stage::after {
  opacity: 1;
}

.deck-stage img {
  width: 100%;
  height: auto;
  aspect-ratio: 16 / 9;
  object-fit: contain;
}

.deck-controls {
  display: grid;
  grid-template-columns: auto minmax(220px, 1fr) auto auto;
  align-items: center;
  gap: 14px;
  padding: 18px;
  color: #f8eee6;
  border-top: 1px solid #2f2c29;
}

.deck-button {
  min-height: 42px;
  padding: 0 16px;
  color: #fff7ef;
  background: #2a2723;
  border: 1px solid #46413c;
  border-radius: 7px;
  font: inherit;
  font-weight: 800;
  cursor: pointer;
}

.deck-button:hover,
.deck-button:focus-visible {
  color: #171613;
  background: #ff8b42;
  border-color: #ff8b42;
}

.deck-button:disabled {
  color: #77716b;
  background: #211f1c;
  border-color: #2e2b27;
  cursor: not-allowed;
}

.deck-progress {
  display: grid;
  grid-template-columns: auto minmax(100px, 1fr);
  align-items: center;
  gap: 14px;
  font-size: 14px;
  font-weight: 800;
}

.deck-progress input {
  width: 100%;
  accent-color: #ff7116;
}

.science-deck-player:fullscreen {
  display: grid;
  grid-template-rows: minmax(0, 1fr) auto;
  width: 100vw;
  height: 100vh;
  max-width: none;
  margin: 0;
  border: 0;
  border-radius: 0;
}

.science-deck-player:fullscreen .deck-stage {
  min-height: 0;
}

.science-deck-player:fullscreen .deck-stage img {
  width: 100%;
  height: 100%;
  object-fit: contain;
}

.science-download-section {
  display: grid;
  grid-template-columns: minmax(0, .85fr) minmax(360px, 1.15fr);
  align-items: center;
  gap: clamp(34px, 7vw, 90px);
  color: #fff8f1;
  background: #1d1b18;
}

.science-download-copy p:not(.eyebrow) {
  margin: 18px 0 0;
  color: #bdb6ae;
  font-size: 17px;
}

.science-file-actions {
  display: grid;
  gap: 14px;
}

.science-file-link {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
  padding: 22px 24px;
  color: #fff8f1;
  background: rgba(255, 255, 255, .07);
  border: 1px solid rgba(255, 255, 255, .16);
  border-radius: 9px;
  transition: background .2s ease, border-color .2s ease, transform .2s ease;
}

.science-file-link:hover,
.science-file-link:focus-visible {
  background: rgba(255, 113, 22, .14);
  border-color: #ff7116;
  transform: translateX(5px);
}

.science-file-link span {
  font-weight: 900;
}

.science-file-link small {
  color: #bdb6ae;
  text-align: right;
}

.visually-hidden {
  position: absolute !important;
  width: 1px !important;
  height: 1px !important;
  padding: 0 !important;
  margin: -1px !important;
  overflow: hidden !important;
  clip: rect(0, 0, 0, 0) !important;
  white-space: nowrap !important;
  border: 0 !important;
}

.site-footer {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: center;
  gap: 10px 22px;
  padding: 28px 20px;
  color: #607080;
  background: #101820;
  font-size: 14px;
  text-align: center;
}

.site-footer p {
  margin: 0;
}

.site-footer a {
  color: #d8e7f5;
  text-decoration: underline;
  text-underline-offset: 3px;
}

@media (max-width: 900px) {
  .section[id] {
    scroll-margin-top: 116px;
  }

  .site-header {
    align-items: flex-start;
    flex-direction: column;
    gap: 10px;
  }

  .nav-links {
    width: 100%;
    justify-content: flex-start;
    overflow-x: auto;
    padding-bottom: 4px;
  }

  .hero,
  .download,
  .detail-band,
  .module-grid,
  .model-showcase,
  .product-gallery-grid,
  .practice-link-grid,
  .science-resource-grid,
  .science-page-hero,
  .science-download-section {
    grid-template-columns: 1fr;
  }

  .science-page-hero {
    min-height: auto;
  }

  .science-page-hero .volunteer-counter {
    max-width: 680px;
  }

  .deck-controls {
    grid-template-columns: 1fr 1fr;
  }

  .deck-progress {
    grid-column: 1 / -1;
    grid-row: 1;
  }

  .deck-fullscreen {
    grid-column: 1 / -1;
  }

  .product-shot-wide {
    grid-column: auto;
  }

  .hero {
    min-height: auto;
  }

  .hero-media {
    justify-self: start;
    width: min(100%, 560px);
  }

  .model-showcase-copy {
    max-width: 780px;
  }

  .model-stage {
    min-height: 400px;
  }

  .flow,
  .notice-grid {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 560px) {
  .section,
  .hero {
    padding-left: 18px;
    padding-right: 18px;
  }

  .button {
    width: 100%;
  }

  dl div,
  .download-panel > div {
    grid-template-columns: 1fr;
  }

  .download-panel > div {
    display: grid;
    gap: 4px;
  }

  .model-stage {
    min-height: 300px;
    aspect-ratio: 1 / 1;
  }

  .model-toolbar,
  .model-spec-list li {
    align-items: flex-start;
    flex-direction: column;
  }

  .model-spec-list strong {
    text-align: left;
  }

  .model-controls {
    width: 100%;
  }

  .science-resource-cover span {
    position: static;
    display: block;
    border-radius: 0;
  }

  .science-file-link {
    align-items: flex-start;
    flex-direction: column;
  }

  .science-file-link small {
    text-align: left;
  }

  .deck-controls {
    gap: 10px;
    padding: 12px;
  }

  .deck-button {
    width: 100%;
    padding: 0 10px;
  }

  .deck-progress {
    grid-template-columns: 1fr;
    gap: 6px;
  }

  .model-control {
    flex: 1;
  }
}

/* ===== 动效 ===== */

/* -- 技术页侧滑入场 -- */
@keyframes slideInPage {
  from { opacity: 0; transform: translateX(40px); }
  to   { opacity: 1; transform: none; }
}
.page-enter {
  animation: slideInPage .5s ease both;
}

/* -- 导航当前页高亮 -- */
.nav-links a.active {
  color: var(--green-dark);
}
.nav-links a.active::after {
  width: 100%;
}

/* -- 返回首页按钮间距 -- */
.back-bar {
  padding: 24px clamp(20px, 6vw, 88px) 0;
}
.back-button {
  min-height: 40px;
  padding: 0 16px;
  font-size: 14px;
}

/* -- keyframes -- */
@keyframes fadeUp {
  from { opacity: 0; transform: translateY(20px); }
  to   { opacity: 1; transform: none; }
}
@keyframes fadeIn {
  from { opacity: 0; }
  to   { opacity: 1; }
}
@keyframes breathe {
  0%, 100% { transform: scale(1); }
  50%      { transform: scale(1.04); }
}

/* -- Hero 首屏入场（纯 CSS，错峰） -- */
.hero .eyebrow {
  animation: fadeUp .6s ease both;
  animation-delay: .1s;
}
#hero-title {
  animation: fadeUp .7s ease both;
  animation-delay: .2s;
}
.hero-lead {
  animation: fadeUp .6s ease both;
  animation-delay: .35s;
}
.hero-actions .button:nth-child(1) {
  animation: fadeUp .5s ease both;
  animation-delay: .5s;
}
.hero-actions .button:nth-child(2) {
  animation: fadeUp .5s ease both;
  animation-delay: .62s;
}
.hero-media {
  animation: fadeIn .8s ease both;
  animation-delay: .3s;
}

/* -- hero 图片呼吸 -- */
.hero-media img {
  animation: breathe 20s ease-in-out infinite;
}

/* -- 滚动入场 .reveal（配合 JS） -- */
.js .reveal {
  opacity: 0;
  transform: translateY(20px);
  transition: opacity .6s ease, transform .6s ease;
}
.js .reveal.is-visible {
  opacity: 1;
  transform: none;
}
.js .flow .flow-step:nth-child(2) { transition-delay: 120ms; }
.js .flow .flow-step:nth-child(3) { transition-delay: 240ms; }
.js .module-grid .module-card:nth-child(2) { transition-delay: 120ms; }
.js .product-gallery-grid .product-shot:nth-child(2) { transition-delay: 100ms; }
.js .product-gallery-grid .product-shot:nth-child(3) { transition-delay: 200ms; }
.js .notice-grid article:nth-child(2) { transition-delay: 100ms; }
.js .notice-grid article:nth-child(3) { transition-delay: 200ms; }
.js .feature-list li:nth-child(2) { transition-delay: 80ms; }
.js .feature-list li:nth-child(3) { transition-delay: 160ms; }
.js .feature-list li:nth-child(4) { transition-delay: 240ms; }

/* -- hover：导航下划线滑入 -- */
.nav-links a {
  position: relative;
  transition: color .2s ease;
}
.nav-links a::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: -4px;
  width: 0;
  height: 2px;
  background: var(--green);
  transition: width .25s ease;
}
.nav-links a:hover::after,
.nav-links a:focus-visible::after {
  width: 100%;
}

/* -- hover：品牌标志 -- */
.brand {
  transition: opacity .2s ease;
}
.brand:hover,
.brand:focus-visible {
  opacity: .85;
}
.brand img {
  transition: transform .3s ease;
}
.brand:hover img,
.brand:focus-visible img {
  transform: scale(1.05);
}

/* -- hover：卡片抬升 -- */
.flow-step,
.module-card,
.notice article {
  transition: transform .25s ease, box-shadow .25s ease;
}
.flow-step:hover,
.module-card:hover,
.notice article:hover {
  transform: translateY(-4px);
  box-shadow: 0 24px 48px rgba(15, 30, 40, 0.10);
}

/* -- hover：能力列表项 -- */
.feature-list li {
  transition: background .2s ease, transform .2s ease;
}
.feature-list li:hover {
  background: rgba(255, 255, 255, 0.14);
  transform: translateX(4px);
}

/* -- hover：按钮增强 -- */
.button:hover,
.button:focus-visible {
  transform: translateY(-3px);
}
.button:active {
  transform: translateY(0);
}
.button.primary:hover,
.button.primary:focus-visible {
  box-shadow: 0 20px 40px rgba(29, 138, 87, 0.28);
}
.button.secondary:hover,
.button.secondary:focus-visible {
  background: #ffffff;
  box-shadow: var(--shadow);
}

/* -- hover：页脚链接 -- */
.site-footer a {
  transition: color .2s ease;
}
.site-footer a:hover {
  color: #ffffff;
}

/* -- reduced-motion 降级 -- */
@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: .01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: .01ms !important;
  }
  html {
    scroll-behavior: auto;
  }
}