/* ImageTwin — 浅色科技风 · 虚拟主机友好 */
:root {
  --bg-deep: #eef2f7;
  --bg-muted: #e2e8f0;
  --bg-card: #ffffff;
  --bg-card-hover: #f8fafc;
  --border: rgba(15, 23, 42, 0.09);
  --border-strong: rgba(8, 145, 178, 0.28);
  --text: #0f172a;
  --text-muted: #64748b;
  --accent: #0891b2;
  --accent-dim: rgba(8, 145, 178, 0.14);
  --violet: #7c3aed;
  --violet-dim: rgba(124, 58, 237, 0.12);
  --success: #059669;
  --radius: 14px;
  --radius-lg: 22px;
  --font-sans: "Plus Jakarta Sans", "PingFang SC", "Microsoft YaHei", sans-serif;
  --font-mono: "JetBrains Mono", "Consolas", monospace;
  --shadow-glow: 0 4px 28px rgba(15, 23, 42, 0.07);
  --header-h: 72px;
}

*,
*::before,
*::after {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: var(--font-sans);
  font-size: 16px;
  line-height: 1.65;
  color: var(--text);
  background: var(--bg-deep);
}

main {
  overflow-x: hidden;
}

/* 背景网格与光晕 */
.bg-layer {
  position: fixed;
  inset: 0;
  z-index: -2;
  background:
    radial-gradient(ellipse 80% 55% at 50% -15%, rgba(8, 145, 178, 0.14), transparent),
    radial-gradient(ellipse 55% 45% at 100% 40%, rgba(124, 58, 237, 0.08), transparent),
    radial-gradient(ellipse 50% 35% at 0% 85%, rgba(8, 145, 178, 0.07), transparent),
    var(--bg-deep);
}

.bg-grid {
  position: fixed;
  inset: 0;
  z-index: -1;
  background-image:
    linear-gradient(rgba(15, 23, 42, 0.045) 1px, transparent 1px),
    linear-gradient(90deg, rgba(15, 23, 42, 0.045) 1px, transparent 1px);
  background-size: 48px 48px;
  mask-image: radial-gradient(ellipse 75% 75% at 50% 35%, black, transparent);
  pointer-events: none;
}

a {
  color: var(--accent);
  text-decoration: none;
  transition: color 0.2s, opacity 0.2s;
}

a:hover {
  color: #0e7490;
}

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

.container {
  width: min(1140px, 92vw);
  margin: 0 auto;
  padding: 0 16px;
}

/* 顶栏 */
.site-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  height: var(--header-h);
  display: flex;
  align-items: center;
  border-bottom: 1px solid var(--border);
  background: rgba(255, 255, 255, 0.86);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
}

.header-inner {
  width: min(1140px, 92vw);
  margin: 0 auto;
  padding: 0 16px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
}

.logo {
  display: flex;
  align-items: center;
  gap: 10px;
  font-weight: 800;
  font-size: 1.25rem;
  letter-spacing: -0.02em;
  color: var(--text);
}

.logo svg {
  flex-shrink: 0;
}

.nav-desktop {
  display: flex;
  align-items: center;
  gap: 6px;
}

.nav-desktop a {
  color: var(--text-muted);
  font-size: 0.9rem;
  font-weight: 500;
  padding: 8px 12px;
  border-radius: 8px;
}

.nav-desktop a:hover {
  color: var(--text);
  background: var(--accent-dim);
}

.header-cta {
  display: flex;
  align-items: center;
  gap: 10px;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 10px 20px;
  font-family: var(--font-sans);
  font-size: 0.9rem;
  font-weight: 600;
  border-radius: 10px;
  border: none;
  cursor: pointer;
  transition: transform 0.15s, box-shadow 0.2s, background 0.2s;
}

.btn:active {
  transform: scale(0.98);
}

.btn-ghost {
  background: transparent;
  color: var(--text-muted);
  border: 1px solid var(--border);
}

.btn-ghost:hover {
  color: var(--text);
  border-color: var(--border-strong);
  background: var(--bg-muted);
}

.btn-primary {
  background: linear-gradient(135deg, #0e7490, #06b6d4);
  color: #ffffff;
  box-shadow: 0 4px 20px rgba(8, 145, 178, 0.35);
}

.btn-primary:hover {
  box-shadow: 0 6px 28px rgba(8, 145, 178, 0.42);
}

.nav-toggle {
  display: none;
  width: 44px;
  height: 44px;
  padding: 0;
  border: 1px solid var(--border);
  border-radius: 10px;
  background: var(--bg-card);
  color: var(--text);
  cursor: pointer;
}

.nav-mobile {
  display: none;
  position: fixed;
  top: var(--header-h);
  left: 0;
  right: 0;
  padding: 16px;
  background: rgba(255, 255, 255, 0.98);
  border-bottom: 1px solid var(--border);
  box-shadow: 0 12px 40px rgba(15, 23, 42, 0.06);
  flex-direction: column;
  gap: 4px;
  z-index: 99;
}

.nav-mobile a {
  color: var(--text);
  padding: 12px 16px;
  border-radius: 10px;
  font-weight: 500;
}

.nav-mobile a:hover {
  background: var(--accent-dim);
}

.nav-mobile.is-open {
  display: flex;
}

/* Hero */
.hero {
  padding: calc(var(--header-h) + 56px) 0 80px;
  position: relative;
}

.hero-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 48px;
  align-items: center;
}

@media (max-width: 900px) {
  .hero-grid {
    grid-template-columns: 1fr;
    text-align: center;
  }

  .hero-actions {
    justify-content: center;
  }

  .hero-badges {
    justify-content: center;
  }
}

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-family: var(--font-mono);
  font-size: 0.75rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: 16px;
}

.eyebrow::before {
  content: "";
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--accent);
  box-shadow: 0 0 12px var(--accent);
  animation: pulse 2s ease-in-out infinite;
}

@keyframes pulse {
  0%,
  100% {
    opacity: 1;
  }
  50% {
    opacity: 0.5;
  }
}

.hero h1 {
  margin: 0 0 20px;
  font-size: clamp(2rem, 5vw, 3rem);
  font-weight: 800;
  line-height: 1.15;
  letter-spacing: -0.03em;
}

.hero h1 .gradient {
  background: linear-gradient(120deg, var(--accent), var(--violet));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero-lead {
  margin: 0 0 28px;
  font-size: 1.05rem;
  color: var(--text-muted);
  max-width: 520px;
}

@media (max-width: 900px) {
  .hero-lead {
    margin-left: auto;
    margin-right: auto;
  }
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-bottom: 28px;
}

.hero-badges {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

.badge {
  font-size: 0.8rem;
  padding: 6px 12px;
  border-radius: 999px;
  border: 1px solid var(--border);
  background: var(--bg-card);
  color: var(--text-muted);
}

.badge strong {
  color: var(--accent);
  font-weight: 600;
}

/* Hero 视觉 */
.hero-visual {
  position: relative;
  min-height: 320px;
}

.hero-card {
  position: relative;
  border-radius: var(--radius-lg);
  border: 1px solid var(--border-strong);
  background: linear-gradient(155deg, #ffffff 0%, #f1f5f9 100%);
  box-shadow: var(--shadow-glow);
  padding: 24px;
  overflow: hidden;
}

.hero-card::before {
  content: "";
  position: absolute;
  top: -50%;
  right: -30%;
  width: 70%;
  height: 100%;
  background: radial-gradient(circle, var(--accent-dim), transparent 70%);
  pointer-events: none;
}

.hero-card-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 20px;
  font-family: var(--font-mono);
  font-size: 0.7rem;
  color: var(--text-muted);
}

.scan-lines {
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.scan-row {
  height: 8px;
  border-radius: 4px;
  background: linear-gradient(90deg, var(--accent-dim), transparent);
  animation: scan 2.5s ease-in-out infinite;
}

.scan-row:nth-child(2) {
  animation-delay: 0.3s;
  width: 85%;
}

.scan-row:nth-child(3) {
  animation-delay: 0.6s;
  width: 70%;
}

@keyframes scan {
  0%,
  100% {
    opacity: 0.4;
  }
  50% {
    opacity: 1;
  }
}

.hero-stats {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 12px;
  margin-top: 20px;
}

.stat-mini {
  padding: 12px;
  border-radius: var(--radius);
  background: var(--bg-muted);
  border: 1px solid var(--border);
  text-align: center;
}

.stat-mini b {
  display: block;
  font-size: 1.25rem;
  color: var(--accent);
  font-variant-numeric: tabular-nums;
}

.stat-mini span {
  font-size: 0.75rem;
  color: var(--text-muted);
}

/* Section 通用 */
section {
  padding: 72px 0;
}

.section-head {
  text-align: center;
  max-width: 640px;
  margin: 0 auto 48px;
}

.section-head h2 {
  margin: 0 0 12px;
  font-size: clamp(1.6rem, 3vw, 2.1rem);
  font-weight: 800;
  letter-spacing: -0.02em;
}

.section-head p {
  margin: 0;
  color: var(--text-muted);
}

/* 功能卡片 */
.features-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 20px;
}

.feature-card {
  padding: 28px;
  border-radius: var(--radius-lg);
  border: 1px solid var(--border);
  background: var(--bg-card);
  backdrop-filter: blur(8px);
  transition: border-color 0.25s, transform 0.25s, box-shadow 0.25s;
}

.feature-card:hover {
  border-color: var(--border-strong);
  transform: translateY(-4px);
  box-shadow: 0 20px 48px rgba(15, 23, 42, 0.1), 0 0 0 1px var(--accent-dim);
}

.feature-icon {
  width: 48px;
  height: 48px;
  border-radius: 12px;
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 16px;
  background: var(--accent-dim);
  color: var(--accent);
}

.feature-card h3 {
  margin: 0 0 10px;
  font-size: 1.1rem;
}

.feature-card p {
  margin: 0;
  font-size: 0.92rem;
  color: var(--text-muted);
}

/* 优势列表 */
.advantages {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 24px;
  counter-reset: adv;
}

.adv-item {
  position: relative;
  padding: 24px 24px 24px 72px;
  border-radius: var(--radius-lg);
  border: 1px solid var(--border);
  background: linear-gradient(160deg, var(--bg-card), transparent);
}

.adv-item::before {
  counter-increment: adv;
  content: counter(adv);
  position: absolute;
  left: 20px;
  top: 24px;
  width: 36px;
  height: 36px;
  border-radius: 10px;
  background: linear-gradient(135deg, var(--violet-dim), var(--accent-dim));
  border: 1px solid var(--border);
  display: flex;
  align-items: center;
  justify-content: center;
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: 0.9rem;
  color: var(--violet);
}

.adv-item h3 {
  margin: 0 0 8px;
  font-size: 1.05rem;
}

.adv-item p {
  margin: 0;
  font-size: 0.9rem;
  color: var(--text-muted);
}

/* 场景 */
.scenarios {
  display: grid;
  gap: 16px;
}

.scenario-row {
  display: grid;
  grid-template-columns: 200px 1fr;
  gap: 24px;
  align-items: start;
  padding: 24px;
  border-radius: var(--radius-lg);
  border: 1px solid var(--border);
  background: var(--bg-card);
}

@media (max-width: 640px) {
  .scenario-row {
    grid-template-columns: 1fr;
  }
}

.scenario-row h3 {
  margin: 0;
  font-size: 1rem;
  color: var(--accent);
}

.scenario-row p {
  margin: 0;
  color: var(--text-muted);
  font-size: 0.95rem;
}

/* 价格 */
.pricing-wrap {
  display: flex;
  justify-content: center;
  width: 100%;
}

.pricing-card {
  width: min(980px, 100%);
  padding: 40px;
  border-radius: var(--radius-lg);
  border: 1px solid var(--border-strong);
  background: linear-gradient(180deg, rgba(8, 145, 178, 0.09), var(--bg-card));
  text-align: center;
  position: relative;
  overflow: hidden;
}

.pricing-card::after {
  content: "";
  position: absolute;
  inset: -1px;
  border-radius: inherit;
  padding: 1px;
  background: linear-gradient(135deg, var(--accent), var(--violet));
  -webkit-mask: linear-gradient(#fff 0 0) content-box, linear-gradient(#fff 0 0);
  mask: linear-gradient(#fff 0 0) content-box, linear-gradient(#fff 0 0);
  -webkit-mask-composite: xor;
  mask-composite: exclude;
  pointer-events: none;
  opacity: 0.5;
}

.pricing-card .price {
  font-size: 3rem;
  font-weight: 800;
  color: var(--accent);
  margin: 8px 0;
  font-variant-numeric: tabular-nums;
}

.pricing-card .price small {
  font-size: 1.1rem;
  font-weight: 600;
  color: var(--text-muted);
}

.pricing-list {
  list-style: none;
  margin: 28px 0;
  padding: 0;
  text-align: left;
}

.pricing-list li {
  padding: 10px 0;
  border-bottom: 1px solid var(--border);
  font-size: 0.95rem;
  color: var(--text-muted);
  display: flex;
  align-items: center;
  gap: 10px;
}

.pricing-list li::before {
  content: "✓";
  color: var(--success);
  font-weight: 700;
}

.pricing-note {
  font-size: 0.85rem;
  color: var(--text-muted);
}

@media (min-width: 860px) {
  .pricing-card {
    display: grid;
    grid-template-columns: 0.9fr 1.1fr;
    gap: 28px 40px;
    align-items: start;
    text-align: left;
  }
  .pricing-card .eyebrow,
  .pricing-card .price,
  .pricing-card .btn {
    justify-content: flex-start;
  }
  .pricing-card .price {
    margin-top: 6px;
  }
  .pricing-list {
    margin: 0;
  }
  .pricing-note {
    margin-top: 12px;
  }

  /* 权益列表三列均衡：按“列”优先填充，避免最后一行缺项导致整体偏左 */
  .pricing-list {
    grid-column: 1 / -1;
    display: grid;
    grid-auto-flow: column;
    grid-template-rows: repeat(3, minmax(0, auto));
    gap: 10px 22px; /* row / column */
    width: 100%;
  }
  .pricing-list li {
    border-bottom: 0;
    padding: 8px 0;
  }

  /* 让 CTA 按钮居中，并跨两列显示 */
  .pricing-card .btn {
    grid-column: 1 / -1;
    width: min(520px, 100%);
    margin: 6px auto 0;
    justify-content: center;
  }
  .pricing-note {
    grid-column: 1 / -1;
    text-align: center;
  }
}

/* 对比表 */
.compare-wrap {
  overflow-x: auto;
  border-radius: var(--radius-lg);
  border: 1px solid var(--border);
}

.compare-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.9rem;
  min-width: 560px;
}

.compare-table th,
.compare-table td {
  padding: 14px 16px;
  text-align: left;
  border-bottom: 1px solid var(--border);
}

.compare-table th {
  background: rgba(8, 145, 178, 0.1);
  color: var(--text);
  font-weight: 600;
}

.compare-table td {
  color: var(--text-muted);
}

.compare-table tr:last-child td {
  border-bottom: none;
}

.compare-table .highlight {
  color: var(--accent);
  font-weight: 600;
}

/* 流程 */
.steps {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 16px;
}

@media (max-width: 900px) {
  .steps {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 480px) {
  .steps {
    grid-template-columns: 1fr;
  }
}

.step {
  padding: 24px;
  border-radius: var(--radius-lg);
  border: 1px solid var(--border);
  background: var(--bg-card);
  position: relative;
}

.step-num {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: var(--violet);
  margin-bottom: 12px;
}

.step h3 {
  margin: 0 0 8px;
  font-size: 1rem;
}

.step p {
  margin: 0;
  font-size: 0.88rem;
  color: var(--text-muted);
}

.alert-box {
  margin-top: 32px;
  padding: 16px 20px;
  border-radius: var(--radius);
  border: 1px solid rgba(245, 158, 11, 0.45);
  background: rgba(255, 251, 235, 0.95);
  color: #b45309;
  font-size: 0.9rem;
}

/* 数据条 */
.metrics {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(140px, 1fr));
  gap: 16px;
}

.metric {
  padding: 20px;
  text-align: center;
  border-radius: var(--radius);
  border: 1px solid var(--border);
  background: var(--bg-card);
}

.metric b {
  display: block;
  font-size: 1.5rem;
  color: var(--accent);
  margin-bottom: 4px;
}

.metric span {
  font-size: 0.8rem;
  color: var(--text-muted);
}

/* 机构与出版生态 Logo 轮播 */
.partners-carousel {
  display: grid;
  grid-template-columns: 44px 1fr 44px;
  align-items: center;
  gap: 12px;
  padding: 18px;
  border-radius: var(--radius-lg);
  border: 1px dashed var(--border);
  background: var(--bg-muted);
}

.pc-btn {
  width: 44px;
  height: 44px;
  border-radius: 14px;
  border: 1px solid var(--border);
  background: var(--bg-card);
  color: var(--text);
  cursor: pointer;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  transition: transform 0.15s, background 0.2s, border-color 0.2s, opacity 0.2s;
}

.pc-btn:hover {
  background: var(--bg-card-hover);
  border-color: var(--border-strong);
}

.pc-btn:active {
  transform: scale(0.98);
}

.pc-btn:disabled {
  opacity: 0.45;
  cursor: not-allowed;
}

.pc-viewport {
  overflow: hidden;
  outline: none;
}

.pc-track {
  display: flex;
  gap: 12px;
  overflow-x: auto;
  padding: 6px 2px;
  /* 不使用 smooth：配合“无限回绕”会在某些浏览器产生抖动/错位感 */
  scroll-behavior: auto;
  -webkit-overflow-scrolling: touch;
  scrollbar-width: none; /* Firefox: hide bar */
}

.pc-track::-webkit-scrollbar {
  display: none; /* WebKit: hide bar */
}

.pc-item {
  flex: 0 0 auto;
  width: 200px;
  height: 84px;
  border-radius: 14px;
  border: 1px solid var(--border);
  background: var(--bg-card);
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 10px 12px;
}

.pc-item img {
  max-width: 100%;
  max-height: 100%;
  object-fit: contain;
  filter: saturate(0.95);
}

@media (max-width: 640px) {
  .partners-carousel {
    grid-template-columns: 40px 1fr 40px;
    padding: 14px;
  }
  .pc-btn {
    width: 40px;
    height: 40px;
    border-radius: 12px;
  }
  .pc-item {
    width: 170px;
    height: 78px;
  }
}

/* 评价 */
.testimonials {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 20px;
}

.quote-card {
  padding: 24px;
  border-radius: var(--radius-lg);
  border: 1px solid var(--border);
  background: var(--bg-card);
}

.quote-card blockquote {
  margin: 0 0 16px;
  font-size: 0.95rem;
  color: var(--text-muted);
  font-style: normal;
  line-height: 1.7;
}

.quote-card cite {
  font-size: 0.85rem;
  color: var(--accent);
  font-style: normal;
  font-weight: 600;
}

/* FAQ */
.faq-list {
  max-width: 720px;
  margin: 0 auto;
}

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

.faq-q {
  width: 100%;
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 16px;
  padding: 20px 0;
  background: none;
  border: none;
  color: var(--text);
  font-family: var(--font-sans);
  font-size: 1rem;
  font-weight: 600;
  text-align: left;
  cursor: pointer;
}

.faq-q:hover {
  color: var(--accent);
}

.faq-icon {
  flex-shrink: 0;
  width: 28px;
  height: 28px;
  border-radius: 8px;
  border: 1px solid var(--border);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.2rem;
  color: var(--accent);
  transition: transform 0.25s;
}

.faq-item.is-open .faq-icon {
  transform: rotate(45deg);
}

.faq-a {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.35s ease;
}

.faq-item.is-open .faq-a {
  max-height: 1200px;
}

.faq-a-inner {
  padding: 0 0 20px;
  color: var(--text-muted);
  font-size: 0.95rem;
}

/* 规避建议 */
.tips-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 16px;
}

.tip-card {
  padding: 20px;
  border-radius: var(--radius);
  border-left: 3px solid var(--accent);
  background: var(--bg-card);
  border-top: 1px solid var(--border);
  border-right: 1px solid var(--border);
  border-bottom: 1px solid var(--border);
}

.tip-card h3 {
  margin: 0 0 8px;
  font-size: 0.95rem;
}

.tip-card p {
  margin: 0;
  font-size: 0.88rem;
  color: var(--text-muted);
}

/* CTA 底部 */
.cta-band {
  padding: 64px 0;
  text-align: center;
  border-top: 1px solid var(--border);
  background: linear-gradient(180deg, transparent, rgba(8, 145, 178, 0.06));
}

.cta-band h2 {
  margin: 0 0 12px;
  font-size: 1.75rem;
}

.cta-band p {
  margin: 0 0 24px;
  color: var(--text-muted);
}

/* Footer */
.site-footer {
  padding: 48px 0 32px;
  border-top: 1px solid var(--border);
}

.footer-grid {
  display: grid;
  grid-template-columns: 1.2fr 1fr 1fr;
  gap: 40px;
  margin-bottom: 40px;
}

@media (max-width: 768px) {
  .footer-grid {
    grid-template-columns: 1fr;
  }

  .nav-desktop {
    display: none;
  }

  .nav-toggle {
    display: flex;
    align-items: center;
    justify-content: center;
  }

  .header-cta .btn-ghost {
    display: none;
  }
}

.footer-brand p {
  margin: 12px 0 0;
  font-size: 0.9rem;
  color: var(--text-muted);
}

.footer-col h4 {
  margin: 0 0 16px;
  font-size: 0.85rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--text-muted);
}

.footer-col ul {
  list-style: none;
  margin: 0;
  padding: 0;
}

.footer-col li {
  margin-bottom: 10px;
}

.footer-col a {
  color: var(--text-muted);
  font-size: 0.9rem;
}

.footer-col a:hover {
  color: var(--accent);
}

.footer-bottom {
  padding-top: 24px;
  border-top: 1px solid var(--border);
  font-size: 0.85rem;
  color: var(--text-muted);
  text-align: center;
}

/* 动画入场
   修复：当 JS 未成功加载时（常见于虚拟主机路径/缓存/拦截），不要把后续内容隐藏掉 */
.reveal {
  opacity: 1;
  transform: none;
}

/* 返回顶部 */
.back-to-top {
  position: fixed;
  right: 20px;
  bottom: 28px;
  z-index: 96;
  width: 48px;
  height: 48px;
  padding: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: 14px;
  border: 1px solid var(--border-strong);
  background: var(--bg-card);
  color: var(--accent);
  cursor: pointer;
  box-shadow: 0 6px 24px rgba(15, 23, 42, 0.1);
  opacity: 0;
  visibility: hidden;
  transform: translateY(14px);
  transition: opacity 0.35s ease, transform 0.35s ease, visibility 0.35s, background 0.2s, color 0.2s;
}

.back-to-top:hover {
  background: var(--accent-dim);
  color: #0e7490;
}

.back-to-top:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
}

.back-to-top.is-visible {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}

/* 右侧隐藏式联系条（仅窄条占位 + 面板绝对定位滑入，避免 body overflow 与嵌套 transform 裁剪/错位） */
.contact-dock {
  --contact-tab-w: 48px;
  position: fixed;
  right: 0;
  top: 50%;
  transform: translateY(-50%);
  z-index: 95;
  width: var(--contact-tab-w);
  overflow: visible;
  pointer-events: none;
}

.contact-dock__panel {
  box-sizing: border-box;
  position: absolute;
  z-index: 1;
  top: 0;
  right: 100%;
  width: min(276px, calc(100vw - var(--contact-tab-w) - 20px));
  padding: 20px 18px;
  border-radius: var(--radius-lg) 0 0 var(--radius-lg);
  border: 1px solid var(--border);
  background: var(--bg-card);
  box-shadow: -8px 8px 32px rgba(15, 23, 42, 0.12);
  transform: translateX(calc(100% + 4px));
  opacity: 0;
  visibility: hidden;
  pointer-events: none;
  transition:
    transform 0.35s cubic-bezier(0.4, 0, 0.2, 1),
    opacity 0.28s ease,
    visibility 0.28s linear;
  transition-delay: 0.12s;
}

.contact-dock:hover .contact-dock__panel,
.contact-dock:focus-within .contact-dock__panel {
  transform: translateX(0);
  opacity: 1;
  visibility: visible;
  pointer-events: auto;
  transition-delay: 0s;
}

.contact-dock__title {
  margin: 0 0 4px;
  font-size: 1rem;
  font-weight: 700;
  color: var(--text);
}

.contact-dock__hint {
  margin: 0 0 16px;
  font-size: 0.8rem;
  color: var(--text-muted);
}

.contact-dock__link {
  display: block;
  padding: 12px 12px;
  margin-bottom: 10px;
  border-radius: var(--radius);
  border: 1px solid var(--border);
  background: var(--bg-muted);
  color: var(--text);
  transition: border-color 0.2s, background 0.2s;
}

.contact-dock__link:hover {
  border-color: var(--border-strong);
  background: var(--bg-card-hover);
  color: var(--text);
}

.contact-dock__label {
  display: block;
  font-size: 0.7rem;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--text-muted);
  margin-bottom: 4px;
}

.contact-dock__value {
  font-size: 0.9rem;
  font-weight: 600;
  word-break: break-all;
}

.contact-dock__mono {
  font-family: var(--font-mono);
  font-size: 0.88rem;
}

.contact-dock__row {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px 10px;
  padding: 12px 12px;
  border-radius: var(--radius);
  border: 1px solid var(--border);
  background: var(--bg-muted);
}

.contact-dock__row .contact-dock__label {
  margin: 0;
  width: 100%;
}

.contact-dock__row .contact-dock__value {
  flex: 1;
  min-width: 0;
}

.contact-dock__copy {
  flex-shrink: 0;
  padding: 6px 12px;
  font-family: var(--font-sans);
  font-size: 0.75rem;
  font-weight: 600;
  border-radius: 8px;
  border: 1px solid var(--border-strong);
  background: var(--bg-card);
  color: var(--accent);
  cursor: pointer;
  transition: background 0.2s, border-color 0.2s;
}

.contact-dock__copy:hover {
  background: var(--accent-dim);
}

.contact-dock__note {
  margin: 14px 0 0;
  font-size: 0.72rem;
  line-height: 1.5;
  color: var(--text-muted);
}

.contact-dock__tab {
  box-sizing: border-box;
  position: relative;
  z-index: 2;
  width: 100%;
  min-height: 120px;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 6px;
  padding: 14px 8px;
  border: none;
  border-radius: var(--radius-lg) 0 0 var(--radius-lg);
  background: linear-gradient(180deg, #0e7490, #0891b2);
  color: #fff;
  cursor: pointer;
  pointer-events: auto;
  font-family: var(--font-sans);
  font-size: 0.72rem;
  font-weight: 700;
  letter-spacing: 0.12em;
  writing-mode: vertical-rl;
  text-orientation: mixed;
  line-height: 1;
  transition: filter 0.2s, box-shadow 0.2s, border-radius 0.25s ease;
  box-shadow: -4px 0 20px rgba(8, 145, 178, 0.25);
}

.contact-dock__tab:hover {
  filter: brightness(1.06);
}

.contact-dock__tab:focus-visible {
  outline: 2px solid var(--violet);
  outline-offset: 2px;
}

.contact-dock__tab-icon {
  writing-mode: horizontal-tb;
  display: flex;
  opacity: 0.95;
}

.contact-dock__tab-text {
  margin-top: 2px;
}

.contact-dock:hover .contact-dock__tab,
.contact-dock:focus-within .contact-dock__tab {
  border-radius: 0;
  box-shadow: none;
}

@media (max-width: 480px) {
  .back-to-top {
    right: 14px;
    bottom: 22px;
    width: 44px;
    height: 44px;
    border-radius: 12px;
  }

  .contact-dock {
    --contact-tab-w: 44px;
  }

  .contact-dock__tab {
    padding: 12px 6px;
    font-size: 0.68rem;
    min-height: 100px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .back-to-top,
  .contact-dock__panel {
    transition-duration: 0.01ms;
  }
}