/* ============================================================
   AIContract 官网落地页样式
   纯静态、无外部依赖（字体/图标均为系统字体与内联 SVG）
   ============================================================ */

:root {
  --brand: #1677ff;
  --brand-dark: #0958d9;
  --brand-deep: #0b2545;
  --purple: #722ed1;
  --cyan: #13c2c2;
  --indigo: #2f54eb;
  --text: #1f2430;
  --text-2: #5a6474;
  --text-3: #8b95a6;
  --line: #e8ecf3;
  --bg-alt: #f6f8fc;
  --radius: 16px;
  --radius-sm: 10px;
  --shadow-sm: 0 2px 10px rgba(15, 35, 70, 0.06);
  --shadow: 0 12px 30px rgba(15, 35, 70, 0.1);
  --shadow-lg: 0 24px 60px rgba(11, 37, 69, 0.18);
  --nav-h: 62px;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
  scroll-padding-top: calc(var(--nav-h) + 12px);
}

body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'PingFang SC', 'Hiragino Sans GB',
    'Microsoft YaHei', 'Helvetica Neue', Arial, sans-serif;
  color: var(--text);
  background: #fff;
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
}

h1,
h2,
h3,
h4,
h5 {
  margin: 0;
  line-height: 1.3;
  font-weight: 700;
}

p {
  margin: 0;
}

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

ul,
ol {
  margin: 0;
  padding: 0;
  list-style: none;
}

code {
  font-family: Consolas, Monaco, 'Courier New', monospace;
  font-size: 0.9em;
  background: #eef3fb;
  color: var(--brand-dark);
  padding: 1px 6px;
  border-radius: 5px;
}

.wrap {
  width: 100%;
  max-width: 1180px;
  margin: 0 auto;
  padding: 0 22px;
}

.wrap-narrow {
  max-width: 860px;
}

/* ===================== 按钮 ===================== */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  border-radius: 999px;
  font-weight: 600;
  white-space: nowrap;
  transition: transform 0.16s ease, box-shadow 0.16s ease, background 0.16s ease, color 0.16s ease;
  border: 1px solid transparent;
  cursor: pointer;
  font-size: 15px;
  padding: 10px 22px;
}

.btn-lg {
  padding: 14px 30px;
  font-size: 16px;
}

.btn-sm {
  padding: 8px 18px;
  font-size: 14px;
}

.btn-block {
  width: 100%;
}

.btn-primary {
  background: linear-gradient(135deg, var(--brand) 0%, var(--brand-dark) 100%);
  color: #fff;
  box-shadow: 0 8px 20px rgba(22, 119, 255, 0.32);
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 12px 26px rgba(22, 119, 255, 0.42);
}

.btn-ghost {
  border-color: rgba(255, 255, 255, 0.5);
  color: #fff;
  background: rgba(255, 255, 255, 0.08);
}

.btn-ghost:hover {
  background: rgba(255, 255, 255, 0.18);
}

.btn-light {
  background: #fff;
  color: var(--brand-dark);
  box-shadow: 0 10px 26px rgba(0, 0, 0, 0.16);
}

.btn-light:hover {
  transform: translateY(-2px);
}

/* ===================== 导航 ===================== */
.nav {
  position: sticky;
  top: 0;
  z-index: 60;
  height: var(--nav-h);
  display: flex;
  align-items: center;
  background: rgba(255, 255, 255, 0.86);
  backdrop-filter: saturate(180%) blur(14px);
  border-bottom: 1px solid transparent;
  transition: box-shadow 0.2s ease, border-color 0.2s ease;
}

.nav.is-scrolled {
  border-bottom-color: var(--line);
  box-shadow: var(--shadow-sm);
}

.nav-inner {
  display: flex;
  align-items: center;
  gap: 20px;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
}

.brand-mark {
  display: inline-flex;
  line-height: 0;
  border-radius: 9px;
  overflow: hidden;
}

.brand-text {
  display: flex;
  flex-direction: column;
}

.brand-text b {
  font-size: 19px;
  letter-spacing: 0.2px;
}

.brand-text i {
  font-style: normal;
  font-size: 11px;
  color: var(--text-3);
  letter-spacing: 0.4px;
}

.nav-links {
  display: flex;
  gap: 26px;
  margin-left: auto;
  font-size: 15px;
  color: var(--text-2);
}

.nav-links a {
  position: relative;
  padding: 4px 0;
}

.nav-links a::after {
  content: '';
  position: absolute;
  left: 0;
  bottom: 0;
  width: 0;
  height: 2px;
  background: var(--brand);
  border-radius: 2px;
  transition: width 0.2s ease;
}

.nav-links a:hover {
  color: var(--brand);
}

.nav-links a:hover::after {
  width: 100%;
}

.nav-actions {
  display: flex;
  align-items: center;
  gap: 12px;
}

.nav-toggle {
  display: none;
  flex-direction: column;
  gap: 4px;
  background: none;
  border: 0;
  padding: 6px;
  cursor: pointer;
}

.nav-toggle span {
  display: block;
  width: 20px;
  height: 2px;
  background: var(--text);
  border-radius: 2px;
}

/* ===================== Hero ===================== */
.hero {
  position: relative;
  overflow: hidden;
  padding: 72px 0 96px;
  background: radial-gradient(120% 120% at 12% 0%, #16407a 0%, #0d2b52 45%, #0a1e3c 100%);
  color: #fff;
}

.hero-bg {
  position: absolute;
  inset: 0;
  pointer-events: none;
}

.orb {
  position: absolute;
  border-radius: 50%;
  filter: blur(46px);
  opacity: 0.5;
}

.orb-1 {
  width: 380px;
  height: 380px;
  top: -120px;
  right: -60px;
  background: radial-gradient(circle, #1677ff 0%, rgba(22, 119, 255, 0) 70%);
}

.orb-2 {
  width: 320px;
  height: 320px;
  bottom: -140px;
  left: -80px;
  background: radial-gradient(circle, #13c2c2 0%, rgba(19, 194, 194, 0) 70%);
}

.orb-3 {
  width: 260px;
  height: 260px;
  top: 40%;
  left: 45%;
  background: radial-gradient(circle, #722ed1 0%, rgba(114, 46, 209, 0) 70%);
  opacity: 0.32;
}

.grid-lines {
  position: absolute;
  inset: 0;
  background-image: linear-gradient(rgba(255, 255, 255, 0.06) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255, 255, 255, 0.06) 1px, transparent 1px);
  background-size: 56px 56px;
  mask-image: radial-gradient(90% 70% at 50% 20%, #000 0%, transparent 78%);
  -webkit-mask-image: radial-gradient(90% 70% at 50% 20%, #000 0%, transparent 78%);
}

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

.pill {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-size: 13px;
  color: rgba(255, 255, 255, 0.88);
  background: rgba(255, 255, 255, 0.1);
  border: 1px solid rgba(255, 255, 255, 0.18);
  padding: 6px 14px;
  border-radius: 999px;
}

.pill b {
  color: #fff;
}

.pill-dot {
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: #52ffb8;
  box-shadow: 0 0 0 4px rgba(82, 255, 184, 0.18);
}

.hero h1 {
  margin: 20px 0 18px;
  font-size: 52px;
  letter-spacing: -0.5px;
}

.hero h1 .grad {
  background: linear-gradient(96deg, #7fc4ff 0%, #52ffb8 100%);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}

.hero-sub {
  font-size: 16px;
  color: rgba(255, 255, 255, 0.82);
  max-width: 560px;
}

.hero-sub b {
  color: #fff;
}

.hero-cta {
  display: flex;
  flex-wrap: wrap;
  gap: 14px;
  margin: 30px 0 26px;
}

.hero-badges {
  display: flex;
  flex-wrap: wrap;
  gap: 10px 22px;
  font-size: 14px;
  color: rgba(255, 255, 255, 0.8);
}

.hero-badges li {
  display: inline-flex;
  align-items: center;
  gap: 8px;
}

.ico-shield,
.ico-ai,
.ico-bolt,
.ico-plug {
  width: 16px;
  height: 16px;
  border-radius: 4px;
  flex: none;
  position: relative;
}

.ico-shield {
  background: linear-gradient(135deg, #52ffb8, #13c2c2);
}

.ico-ai {
  background: linear-gradient(135deg, #7fc4ff, #1677ff);
}

.ico-bolt {
  background: linear-gradient(135deg, #ffd666, #fa8c16);
}

.ico-plug {
  background: linear-gradient(135deg, #d3adf7, #722ed1);
}

/* ---- Hero 应用界面示意 ---- */
.hero-visual {
  position: relative;
}

.mock {
  background: #fff;
  border-radius: 14px;
  box-shadow: var(--shadow-lg);
  overflow: hidden;
  color: var(--text);
}

.mock-bar {
  display: flex;
  align-items: center;
  gap: 6px;
  padding: 10px 14px;
  background: #f3f5f9;
  border-bottom: 1px solid var(--line);
}

.dot {
  width: 10px;
  height: 10px;
  border-radius: 50%;
}

.dot-r {
  background: #ff5f57;
}
.dot-y {
  background: #febc2e;
}
.dot-g {
  background: #28c840;
}

.mock-title {
  margin-left: 8px;
  font-size: 12px;
  color: var(--text-3);
}

.mock-body {
  display: grid;
  grid-template-columns: 148px 1fr;
  min-height: 268px;
}

.mock-side {
  background: #fafbfe;
  border-right: 1px solid var(--line);
  padding: 12px 10px;
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.mock-side-item {
  font-size: 12.5px;
  color: var(--text-2);
  padding: 7px 10px;
  border-radius: 8px;
}

.mock-side-item.is-active {
  background: #e8f2ff;
  color: var(--brand-dark);
  font-weight: 600;
}

.mock-main {
  padding: 14px;
}

.mock-hero {
  border-radius: 12px;
  padding: 16px 18px;
  background: linear-gradient(120deg, #16407a 0%, #1677ff 100%);
  color: #fff;
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.mock-hero b {
  font-size: 16px;
}

.mock-hero i {
  font-style: normal;
  font-size: 12px;
  color: rgba(255, 255, 255, 0.82);
}

.mock-cards {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 10px;
  margin-top: 12px;
}

.mock-card {
  border-radius: 12px;
  padding: 12px;
  display: flex;
  flex-direction: column;
  gap: 6px;
  border: 1px solid var(--line);
}

.mock-card-title {
  font-size: 12.5px;
  font-weight: 600;
}

.mock-card-num {
  font-size: 22px;
  font-weight: 700;
  line-height: 1.1;
  display: flex;
  flex-direction: column;
}

.mock-card-num i {
  font-style: normal;
  font-size: 10.5px;
  font-weight: 400;
  color: var(--text-3);
  margin-top: 2px;
}

.mock-card-bar {
  height: 5px;
  border-radius: 4px;
  background: #eef1f6;
  overflow: hidden;
}

.mock-card-bar b {
  display: block;
  height: 100%;
  border-radius: 4px;
  background: currentColor;
  opacity: 0.55;
}

.c-blue {
  background: linear-gradient(135deg, #f0f7ff, #fff);
  color: var(--brand);
  border-color: #d6e8ff;
}

.c-purple {
  background: linear-gradient(135deg, #f7f3ff, #fff);
  color: var(--purple);
  border-color: #e9def9;
}

.c-cyan {
  background: linear-gradient(135deg, #f0fdfa, #fff);
  color: var(--cyan);
  border-color: #d3f5f2;
}

.mock-card-title,
.mock-card-num {
  color: var(--text);
}

.mock-tag {
  position: absolute;
  background: #fff;
  color: var(--text);
  font-size: 12.5px;
  font-weight: 600;
  padding: 7px 14px;
  border-radius: 999px;
  box-shadow: var(--shadow);
  animation: float 5.5s ease-in-out infinite;
}

.mock-tag-1 {
  top: 26px;
  left: -26px;
}

.mock-tag-2 {
  bottom: 34px;
  right: -18px;
  animation-delay: 1.4s;
}

@keyframes float {
  0%,
  100% {
    transform: translateY(0);
  }
  50% {
    transform: translateY(-9px);
  }
}

/* ===================== 通用区块 ===================== */
.section {
  padding: 84px 0;
}

.section-alt {
  background: var(--bg-alt);
}

.section-head {
  text-align: center;
  max-width: 720px;
  margin: 0 auto 46px;
}

.eyebrow {
  display: inline-block;
  font-size: 13px;
  font-weight: 600;
  color: var(--brand);
  background: #e8f2ff;
  padding: 5px 14px;
  border-radius: 999px;
  margin-bottom: 16px;
  letter-spacing: 0.3px;
}

.section-head h2 {
  font-size: 34px;
  letter-spacing: -0.3px;
}

.section-head p {
  margin-top: 14px;
  color: var(--text-2);
  font-size: 15.5px;
}

/* ===================== 核心功能卡片 ===================== */
.card-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 20px;
}

.feature-card {
  background: #fff;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 26px;
  transition: transform 0.2s ease, box-shadow 0.2s ease, border-color 0.2s ease;
}

.feature-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow);
  border-color: #d6e8ff;
}

.feature-icon {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 44px;
  height: 44px;
  border-radius: 12px;
  margin-bottom: 16px;
}

.f-blue {
  background: #e8f2ff;
  color: var(--brand);
}

.f-indigo {
  background: #eaefff;
  color: var(--indigo);
}

.f-purple {
  background: #f4ecfd;
  color: var(--purple);
}

.f-cyan {
  background: #e4fbfa;
  color: var(--cyan);
}

.feature-card h3 {
  font-size: 19px;
  margin-bottom: 10px;
}

.feature-card p {
  color: var(--text-2);
  font-size: 14.5px;
}

.feature-list {
  margin-top: 16px;
  padding-top: 14px;
  border-top: 1px dashed var(--line);
  display: flex;
  flex-direction: column;
  gap: 7px;
}

.feature-list li {
  position: relative;
  padding-left: 18px;
  font-size: 13.5px;
  color: var(--text-2);
}

.feature-list li::before {
  content: '';
  position: absolute;
  left: 2px;
  top: 9px;
  width: 6px;
  height: 6px;
  border-radius: 2px;
  background: var(--brand);
  opacity: 0.7;
}

.sub-block {
  margin-top: 54px;
}

.sub-title {
  font-size: 19px;
  text-align: center;
  margin-bottom: 24px;
}

.chip-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 14px;
}

.chip {
  background: #fff;
  border: 1px solid var(--line);
  border-radius: var(--radius-sm);
  padding: 16px 18px;
  display: flex;
  flex-direction: column;
  gap: 4px;
  transition: box-shadow 0.2s ease, transform 0.2s ease;
}

.chip:hover {
  box-shadow: var(--shadow-sm);
  transform: translateY(-2px);
}

.chip b {
  font-size: 14.5px;
}

.chip span {
  font-size: 12.5px;
  color: var(--text-3);
}

/* ===================== 流程步骤 ===================== */
.steps {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
  counter-reset: step;
}

.steps li {
  position: relative;
  background: #fff;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 26px 22px;
}

.steps li::after {
  content: '';
  position: absolute;
  top: 38px;
  right: -14px;
  width: 14px;
  height: 2px;
  background: linear-gradient(90deg, var(--line), transparent);
}

.steps li:last-child::after {
  display: none;
}

.step-no {
  display: inline-block;
  font-size: 13px;
  font-weight: 700;
  color: var(--brand);
  background: #e8f2ff;
  border-radius: 8px;
  padding: 3px 10px;
  margin-bottom: 14px;
  letter-spacing: 1px;
}

.steps h4 {
  font-size: 16.5px;
  margin-bottom: 8px;
}

.steps p {
  font-size: 13.5px;
  color: var(--text-2);
}

/* ===================== 界面预览 ===================== */
.preview-wrap {
  max-width: 900px;
  margin: 0 auto;
}

.mock-flat {
  border: 1px solid var(--line);
  box-shadow: var(--shadow);
}

.mock-table {
  padding: 8px 10px 4px;
  overflow-x: auto;
}

.mock-tr {
  display: grid;
  grid-template-columns: 130px 1.4fr 1.2fr 120px 90px 80px;
  gap: 10px;
  align-items: center;
  padding: 11px 12px;
  font-size: 13px;
  border-radius: 8px;
  color: var(--text-2);
  min-width: 720px;
}

.mock-th {
  background: #f5f7fb;
  color: var(--text-3);
  font-weight: 600;
  font-size: 12.5px;
}

.mock-tr:not(.mock-th):hover {
  background: #f8faff;
}

.mock-tr > span:first-child {
  color: var(--text);
  font-weight: 600;
}

.tag {
  display: inline-block;
  font-size: 12px;
  padding: 2px 10px;
  border-radius: 999px;
  text-align: center;
  font-weight: 500;
}

.tag-green {
  background: #e9f9ee;
  color: #17a34a;
}

.tag-blue {
  background: #e8f2ff;
  color: var(--brand-dark);
}

.tag-orange {
  background: #fff4e6;
  color: #d46b08;
}

.mock-hint {
  text-align: center;
  font-size: 12px;
  color: var(--text-3);
  padding: 10px 0 16px;
}

/* ===================== 价值点 ===================== */
.value-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 18px;
}

.value-item {
  background: #fff;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 24px 22px;
  transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.value-item:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow);
}

.value-item h4 {
  font-size: 16.5px;
  margin-bottom: 10px;
  padding-left: 14px;
  position: relative;
}

.value-item h4::before {
  content: '';
  position: absolute;
  left: 0;
  top: 4px;
  bottom: 4px;
  width: 4px;
  border-radius: 3px;
  background: linear-gradient(180deg, var(--brand), var(--cyan));
}

.value-item p {
  font-size: 14px;
  color: var(--text-2);
}

/* ===================== 下载区 ===================== */
.download-card {
  display: grid;
  grid-template-columns: 1.15fr 1fr;
  gap: 0;
  border: 1px solid var(--line);
  border-radius: 20px;
  overflow: hidden;
  box-shadow: var(--shadow);
  background: #fff;
}

.download-main {
  padding: 34px;
}

.download-head {
  display: flex;
  align-items: center;
  gap: 14px;
  margin-bottom: 24px;
}

.win-logo {
  width: 50px;
  height: 50px;
  border-radius: 14px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  background: #f0f5ff;
  color: var(--brand);
  flex: none;
}

.download-head b {
  display: block;
  font-size: 17px;
}

.download-head span {
  font-size: 13px;
  color: var(--text-3);
}

.download-note {
  margin-top: 16px;
  font-size: 13px;
  color: var(--text-2);
  background: #f7f9fc;
  border: 1px dashed var(--line);
  border-radius: 10px;
  padding: 12px 14px;
}

.download-meta {
  margin-top: 22px;
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 12px 18px;
}

.download-meta li {
  display: flex;
  flex-direction: column;
  gap: 2px;
  font-size: 13.5px;
  padding-bottom: 10px;
  border-bottom: 1px solid var(--line);
}

.download-meta b {
  font-size: 12px;
  color: var(--text-3);
  font-weight: 500;
}

.download-side {
  background: var(--bg-alt);
  border-left: 1px solid var(--line);
  padding: 34px 30px;
}

.download-side h4 {
  font-size: 16px;
  margin-bottom: 16px;
}

.install-steps {
  display: flex;
  flex-direction: column;
  gap: 12px;
  counter-reset: ins;
}

.install-steps li {
  position: relative;
  padding-left: 32px;
  font-size: 14px;
  color: var(--text-2);
}

.install-steps li::before {
  counter-increment: ins;
  content: counter(ins);
  position: absolute;
  left: 0;
  top: 2px;
  width: 20px;
  height: 20px;
  border-radius: 50%;
  background: var(--brand);
  color: #fff;
  font-size: 12px;
  font-weight: 700;
  display: flex;
  align-items: center;
  justify-content: center;
}

.req {
  margin-top: 26px;
  padding-top: 20px;
  border-top: 1px solid var(--line);
}

.req h5 {
  font-size: 14px;
  margin-bottom: 10px;
}

.req ul {
  display: flex;
  flex-direction: column;
  gap: 7px;
}

.req li {
  position: relative;
  padding-left: 16px;
  font-size: 13.5px;
  color: var(--text-2);
}

.req li::before {
  content: '';
  position: absolute;
  left: 0;
  top: 9px;
  width: 5px;
  height: 5px;
  border-radius: 50%;
  background: var(--text-3);
}

/* ---- 更新日志 ---- */
.changelog {
  margin-top: 28px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 26px 30px;
  background: #fff;
}

.changelog-head {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-bottom: 16px;
}

.changelog-head h3 {
  font-size: 17px;
}

.changelog-ver {
  font-size: 12.5px;
  font-weight: 600;
  color: var(--brand-dark);
  background: #e8f2ff;
  padding: 3px 12px;
  border-radius: 999px;
}

.changelog-list {
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.changelog-list li {
  position: relative;
  padding-left: 20px;
  font-size: 14px;
  color: var(--text-2);
}

.changelog-list li::before {
  content: '';
  position: absolute;
  left: 4px;
  top: 9px;
  width: 6px;
  height: 6px;
  border-radius: 2px;
  background: var(--brand);
}

.changelog-more {
  margin-top: 18px;
  padding-top: 14px;
  border-top: 1px dashed var(--line);
  font-size: 13px;
  color: var(--text-3);
}

.changelog-more a {
  color: var(--brand);
}

/* ===================== FAQ ===================== */
.faq-list {
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.faq {
  background: #fff;
  border: 1px solid var(--line);
  border-radius: var(--radius-sm);
  padding: 16px 20px;
  transition: box-shadow 0.2s ease;
}

.faq[open] {
  box-shadow: var(--shadow-sm);
}

.faq summary {
  cursor: pointer;
  font-weight: 600;
  font-size: 15.5px;
  list-style: none;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
}

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

.faq summary::after {
  content: '+';
  font-size: 20px;
  font-weight: 400;
  color: var(--brand);
  line-height: 1;
}

.faq[open] summary::after {
  content: '−';
}

.faq p {
  margin-top: 12px;
  font-size: 14px;
  color: var(--text-2);
}

/* ===================== 结尾 CTA ===================== */
.cta {
  background: linear-gradient(120deg, #0b2545 0%, #16407a 55%, #1677ff 100%);
  color: #fff;
  padding: 62px 0;
}

.cta-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 28px;
  flex-wrap: wrap;
}

.cta h2 {
  font-size: 27px;
}

.cta p {
  margin-top: 10px;
  color: rgba(255, 255, 255, 0.82);
  font-size: 15px;
}

/* ===================== 页脚 ===================== */
.footer {
  background: #08182e;
  color: rgba(255, 255, 255, 0.72);
  padding: 52px 0 22px;
}

.footer-inner {
  display: grid;
  grid-template-columns: 1.2fr 2fr;
  gap: 40px;
  padding-bottom: 34px;
  border-bottom: 1px solid rgba(255, 255, 255, 0.1);
}

.brand-footer {
  color: #fff;
  margin-bottom: 14px;
}

.footer-brand p {
  font-size: 13.5px;
  max-width: 300px;
}

.footer-cols {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.footer-col {
  display: flex;
  flex-direction: column;
  gap: 9px;
  font-size: 13.5px;
}

.footer-col h5 {
  color: #fff;
  font-size: 14px;
  margin-bottom: 3px;
}

.footer-col a:hover {
  color: #fff;
}

.footer-muted {
  color: rgba(255, 255, 255, 0.45);
}

.footer-bottom {
  display: flex;
  flex-wrap: wrap;
  gap: 10px 24px;
  justify-content: space-between;
  align-items: center;
  padding-top: 20px;
  font-size: 12.5px;
  color: rgba(255, 255, 255, 0.5);
}

.beian:hover {
  color: rgba(255, 255, 255, 0.85);
}

/* ===================== 返回顶部 ===================== */
.to-top {
  position: fixed;
  right: 22px;
  bottom: 26px;
  width: 42px;
  height: 42px;
  border-radius: 50%;
  background: #fff;
  color: var(--brand);
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: var(--shadow);
  opacity: 0;
  visibility: hidden;
  transform: translateY(8px);
  transition: all 0.22s ease;
  z-index: 50;
}

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

/* ===================== 滚动渐显 ===================== */
.reveal {
  opacity: 0;
  transform: translateY(18px);
  transition: opacity 0.55s ease, transform 0.55s ease;
}

.reveal.is-in {
  opacity: 1;
  transform: none;
}

@media (prefers-reduced-motion: reduce) {
  .reveal {
    opacity: 1;
    transform: none;
    transition: none;
  }

  .mock-tag,
  html {
    animation: none;
    scroll-behavior: auto;
  }
}

/* ===================== 响应式 ===================== */
@media (max-width: 1024px) {
  .hero h1 {
    font-size: 42px;
  }

  .hero-inner {
    grid-template-columns: 1fr;
    gap: 46px;
  }

  .hero-visual {
    max-width: 560px;
  }

  .chip-grid,
  .steps,
  .value-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .steps li::after {
    display: none;
  }

  .download-card {
    grid-template-columns: 1fr;
  }

  .download-side {
    border-left: 0;
    border-top: 1px solid var(--line);
  }
}

@media (max-width: 760px) {
  :root {
    --nav-h: 58px;
  }

  .nav-links {
    position: absolute;
    top: var(--nav-h);
    left: 0;
    right: 0;
    flex-direction: column;
    gap: 0;
    background: #fff;
    border-bottom: 1px solid var(--line);
    box-shadow: var(--shadow);
    padding: 6px 22px 14px;
    display: none;
  }

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

  .nav-links a {
    padding: 11px 0;
    border-bottom: 1px solid var(--line);
  }

  .nav-toggle {
    display: flex;
  }

  .nav-actions .btn {
    display: none;
  }

  .hero {
    padding: 48px 0 68px;
  }

  .hero h1 {
    font-size: 34px;
  }

  .hero-sub {
    font-size: 15px;
  }

  .btn-lg {
    padding: 12px 22px;
    font-size: 15px;
  }

  .section {
    padding: 60px 0;
  }

  .section-head h2 {
    font-size: 26px;
  }

  .card-grid,
  .chip-grid,
  .steps,
  .value-grid,
  .footer-inner,
  .footer-cols {
    grid-template-columns: 1fr;
  }

  .download-main,
  .download-side,
  .changelog {
    padding: 24px 20px;
  }

  .download-meta {
    grid-template-columns: 1fr;
  }

  .mock-tag {
    display: none;
  }

  /* 窄屏下收窄侧栏、功能卡改为竖排，避免界面示意被压得读不清 */
  .mock-body {
    grid-template-columns: 116px 1fr;
    min-height: auto;
  }

  .mock-main {
    padding: 12px;
  }

  .mock-side {
    padding: 10px 8px;
  }

  .mock-side-item {
    font-size: 12px;
    padding: 6px 8px;
  }

  .mock-cards {
    grid-template-columns: 1fr;
    gap: 8px;
  }

  .mock-card {
    padding: 10px 12px;
  }

  .mock-card-num {
    font-size: 20px;
  }

  .cta h2 {
    font-size: 22px;
  }

  .cta-inner .btn {
    width: 100%;
  }
}