/* ==========================================================================
   未笺 NORVAE · 官方网站与单机交互演示系统 (2026-2027 前沿美学规范)
   ========================================================================== */

:root {
  /* 深海夜空调色板 (默认) */
  --bg-base: #060B0E;
  --bg-elevated: #0B1418;
  --bg-card: rgba(16, 27, 33, 0.65);
  --bg-card-hover: rgba(22, 37, 44, 0.85);
  --bg-glass: rgba(12, 22, 27, 0.72);
  --border-glass: rgba(255, 255, 255, 0.08);
  --border-highlight: rgba(72, 229, 194, 0.35);

  --accent: #3AD5AF;
  --accent-light: #5FF2CD;
  --accent-glow: rgba(58, 213, 175, 0.28);
  --accent-subtle: rgba(58, 213, 175, 0.12);

  --amber: #E8A856;
  --amber-glow: rgba(232, 168, 86, 0.30);

  --text-primary: #F3F7F8;
  --text-secondary: #9EB0B6;
  --text-tertiary: #5D727A;

  --nav-height: 72px;
  --container-max: 1200px;
  --radius-sm: 8px;
  --radius-md: 16px;
  --radius-lg: 24px;
  --radius-pill: 9999px;

  --font-sans: -apple-system, BlinkMacSystemFont, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Noto Sans SC", sans-serif;
  --font-serif: "Songti SC", "SimSun", "Noto Serif SC", serif;
  --font-brand: "NORVAEBrand", "PingFang SC", "Noto Sans SC", sans-serif;

  --shadow-card: 0 12px 36px -8px rgba(0, 0, 0, 0.55), 0 0 0 1px var(--border-glass);
  --shadow-glow: 0 0 28px -4px var(--accent-glow);
  --transition-smooth: all 0.36s cubic-bezier(0.16, 1, 0.3, 1);
}

[data-theme="light"] {
  --bg-base: #F5F1E9;
  --bg-elevated: #ECE6DB;
  --bg-card: rgba(255, 255, 255, 0.75);
  --bg-card-hover: rgba(255, 255, 255, 0.95);
  --bg-glass: rgba(248, 244, 238, 0.82);
  --border-glass: rgba(25, 40, 46, 0.08);
  --border-highlight: rgba(42, 143, 122, 0.35);

  --accent: #2A8F7A;
  --accent-light: #36AD95;
  --accent-glow: rgba(42, 143, 122, 0.22);
  --accent-subtle: rgba(42, 143, 122, 0.08);

  --amber: #C97D29;
  --amber-glow: rgba(201, 125, 41, 0.25);

  --text-primary: #19272C;
  --text-secondary: #586B72;
  --text-tertiary: #8C9EA4;

  --shadow-card: 0 12px 32px -8px rgba(45, 60, 66, 0.09), 0 0 0 1px var(--border-glass);
}

/* 全局重置与平滑滚动 */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  font-family: var(--font-sans);
  background-color: var(--bg-base);
  color: var(--text-primary);
  scroll-behavior: smooth;
  text-rendering: optimizeLegibility;
  -webkit-font-smoothing: antialiased;
}

body {
  overflow-x: hidden;
  line-height: 1.65;
  min-height: 100vh;
  position: relative;
  background-color: var(--bg-base);
  transition: background-color 0.4s ease, color 0.4s ease;
}

/* 动态背景画布 */
#ambient-canvas {
  position: fixed;
  top: 0;
  left: 0;
  width: 100vw;
  height: 100vh;
  z-index: 0;
  pointer-events: none;
}

/* 页面主要内容容器 */
.app-container {
  position: relative;
  z-index: 1;
}

.section-wrapper {
  max-width: var(--container-max);
  margin: 0 auto;
  padding: 0 24px;
}

/* ==========================================================================
   导航栏 Header & Nav
   ========================================================================== */
.site-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  height: var(--nav-height);
  z-index: 100;
  transition: var(--transition-smooth);
}

.site-header.scrolled {
  background: var(--bg-glass);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-bottom: 1px solid var(--border-glass);
  box-shadow: 0 4px 20px rgba(0, 0, 0, 0.2);
}

.nav-container {
  max-width: var(--container-max);
  height: 100%;
  margin: 0 auto;
  padding: 0 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.brand-link {
  display: flex;
  align-items: center;
  gap: 12px;
  text-decoration: none;
  color: inherit;
}

.brand-logo-glow {
  width: 38px;
  height: 38px;
  position: relative;
  display: flex;
  align-items: center;
  justify-content: center;
}

.brand-logo-glow canvas {
  width: 100%;
  height: 100%;
}

.brand-logo-glow img {
  display: block;
  width: 32px;
  height: 32px;
  border-radius: 7px;
}

.brand-name {
  font-size: 20px;
  font-weight: 500;
  letter-spacing: 2px;
  color: var(--text-primary);
}

.brand-badge {
  font-size: 11px;
  padding: 2px 8px;
  border-radius: var(--radius-pill);
  background: var(--accent-subtle);
  color: var(--accent);
  border: 1px solid var(--border-highlight);
  font-weight: 600;
  letter-spacing: 0.5px;
}

.nav-menu {
  display: flex;
  align-items: center;
  gap: 32px;
  list-style: none;
}

.nav-link {
  text-decoration: none;
  color: var(--text-secondary);
  font-size: 14px;
  font-weight: 450;
  transition: color 0.2s ease;
  position: relative;
  padding: 6px 0;
}

.nav-link:hover, .nav-link.active {
  color: var(--text-primary);
}

.nav-link::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 0;
  height: 2px;
  background: var(--accent);
  transition: width 0.3s ease;
  border-radius: 2px;
}

.nav-link:hover::after, .nav-link.active::after {
  width: 100%;
}

.nav-actions {
  display: flex;
  align-items: center;
  gap: 14px;
}

/* 控制按钮（主题、声音） */
.icon-btn {
  background: var(--bg-card);
  border: 1px solid var(--border-glass);
  color: var(--text-secondary);
  width: 40px;
  height: 40px;
  border-radius: var(--radius-pill);
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  transition: var(--transition-smooth);
}

.icon-btn:hover {
  color: var(--text-primary);
  border-color: var(--border-highlight);
  transform: translateY(-1px);
}

.btn-primary {
  background: linear-gradient(135deg, var(--accent), var(--accent-light));
  color: #051614;
  border: none;
  padding: 10px 22px;
  border-radius: var(--radius-pill);
  font-size: 14px;
  font-weight: 600;
  cursor: pointer;
  text-decoration: none;
  display: inline-flex;
  align-items: center;
  gap: 8px;
  box-shadow: 0 4px 18px var(--accent-glow);
  transition: var(--transition-smooth);
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 6px 24px var(--accent-glow);
}

.btn-secondary {
  background: var(--bg-card);
  color: var(--text-primary);
  border: 1px solid var(--border-glass);
  padding: 10px 22px;
  border-radius: var(--radius-pill);
  font-size: 14px;
  font-weight: 500;
  cursor: pointer;
  text-decoration: none;
  display: inline-flex;
  align-items: center;
  gap: 8px;
  backdrop-filter: blur(12px);
  transition: var(--transition-smooth);
}

.btn-secondary:hover {
  border-color: var(--border-highlight);
  background: var(--bg-card-hover);
  transform: translateY(-1px);
}

/* ==========================================================================
   Hero 首屏 (沉浸意境与品牌微图腾)
   ========================================================================== */
.hero-section {
  min-height: 96vh;
  padding-top: calc(var(--nav-height) + 40px);
  padding-bottom: 60px;
  display: flex;
  align-items: center;
  position: relative;
}

.hero-grid {
  display: grid;
  grid-template-columns: 1.15fr 0.85fr;
  align-items: center;
  gap: 48px;
}

.hero-eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 6px 16px;
  background: var(--accent-subtle);
  border: 1px solid var(--border-highlight);
  border-radius: var(--radius-pill);
  color: var(--accent);
  font-size: 13px;
  font-weight: 500;
  letter-spacing: 1px;
  margin-bottom: 24px;
}

.hero-title {
  font-size: clamp(38px, 5.2vw, 64px);
  font-weight: 650;
  line-height: 1.18;
  letter-spacing: -0.5px;
  margin-bottom: 24px;
}

.hero-title .gradient-text {
  background: linear-gradient(135deg, var(--text-primary) 30%, var(--accent) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.hero-subtitle {
  font-size: clamp(16px, 1.8vw, 19px);
  color: var(--text-secondary);
  line-height: 1.75;
  margin-bottom: 36px;
  max-width: 540px;
}

.hero-cta {
  display: flex;
  flex-wrap: wrap;
  gap: 16px;
  align-items: center;
  margin-bottom: 32px;
}

.hero-meta {
  display: flex;
  align-items: center;
  gap: 24px;
  font-size: 12px;
  color: var(--text-tertiary);
}

.hero-meta-item {
  display: flex;
  align-items: center;
  gap: 6px;
}

/* Hero 右侧：灵动折面浮岛 3D Canvas 容器 */
.hero-totem-card {
  position: relative;
  width: 100%;
  aspect-ratio: 1;
  max-width: 440px;
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: center;
}

.totem-canvas-wrapper {
  position: relative;
  width: 100%;
  height: 100%;
}

#hero-totem-canvas {
  width: 100%;
  height: 100%;
  display: block;
}

.totem-ambient-glow {
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  width: 280px;
  height: 280px;
  border-radius: 50%;
  background: radial-gradient(circle, var(--accent-glow) 0%, transparent 70%);
  filter: blur(40px);
  z-index: -1;
  pointer-events: none;
}

/* ==========================================================================
   四重慢生世界观 · 核心特性
   ========================================================================== */
.features-section {
  padding: 100px 0;
  position: relative;
}

.section-header {
  text-align: center;
  max-width: 680px;
  margin: 0 auto 64px;
}

.section-tag {
  color: var(--accent);
  font-size: 13px;
  font-weight: 600;
  letter-spacing: 3px;
  text-transform: uppercase;
  margin-bottom: 12px;
  display: block;
}

.section-title {
  font-size: clamp(28px, 3.6vw, 42px);
  font-weight: 600;
  line-height: 1.25;
  margin-bottom: 16px;
}

.section-desc {
  font-size: 16px;
  color: var(--text-secondary);
  line-height: 1.7;
}

.features-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 24px;
}

.feature-card {
  background: var(--bg-card);
  border: 1px solid var(--border-glass);
  border-radius: var(--radius-lg);
  padding: 36px 28px;
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  box-shadow: var(--shadow-card);
  transition: var(--transition-smooth);
  display: flex;
  flex-direction: column;
  position: relative;
  overflow: hidden;
}

.feature-card:hover {
  transform: translateY(-6px);
  border-color: var(--border-highlight);
  background: var(--bg-card-hover);
  box-shadow: var(--shadow-card), var(--shadow-glow);
}

.feature-icon-box {
  width: 54px;
  height: 54px;
  border-radius: var(--radius-md);
  background: var(--accent-subtle);
  border: 1px solid var(--border-highlight);
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 24px;
  color: var(--accent);
}

.feature-card h3 {
  font-size: 20px;
  font-weight: 600;
  margin-bottom: 12px;
  color: var(--text-primary);
}

.feature-card p {
  font-size: 14.5px;
  color: var(--text-secondary);
  line-height: 1.7;
  flex-grow: 1;
}

.feature-pill-tag {
  align-self: flex-start;
  margin-top: 20px;
  font-size: 12px;
  padding: 4px 12px;
  border-radius: var(--radius-pill);
  background: rgba(255, 255, 255, 0.04);
  color: var(--accent);
  border: 1px solid var(--border-glass);
}

/* ==========================================================================
   未笺单机交互体验舱 · Interactive Simulator Sandbox
   ========================================================================== */
.sandbox-section {
  padding: 100px 0;
  position: relative;
}

.sandbox-container {
  background: var(--bg-elevated);
  border: 1px solid var(--border-glass);
  border-radius: 32px;
  padding: 48px;
  box-shadow: 0 24px 60px -12px rgba(0, 0, 0, 0.6);
  position: relative;
  overflow: hidden;
}

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

.sandbox-intro {
  display: flex;
  flex-direction: column;
  gap: 20px;
}

.sandbox-nav-tabs {
  display: flex;
  flex-direction: column;
  gap: 12px;
  margin-top: 16px;
}

.sandbox-tab-btn {
  display: flex;
  align-items: flex-start;
  gap: 16px;
  padding: 16px 20px;
  border-radius: var(--radius-md);
  background: transparent;
  border: 1px solid transparent;
  color: var(--text-secondary);
  cursor: pointer;
  text-align: left;
  transition: var(--transition-smooth);
}

.sandbox-tab-btn:hover {
  background: var(--bg-card);
  color: var(--text-primary);
}

.sandbox-tab-btn.active {
  background: var(--bg-card);
  border-color: var(--border-highlight);
  color: var(--text-primary);
  box-shadow: 0 4px 20px var(--accent-glow);
}

.tab-btn-icon {
  font-size: 20px;
  color: var(--accent);
  margin-top: 2px;
}

.tab-btn-content strong {
  display: block;
  font-size: 15px;
  font-weight: 600;
  margin-bottom: 4px;
}

.tab-btn-content span {
  font-size: 13px;
  color: var(--text-tertiary);
  line-height: 1.5;
}

/* 手机高保真视口模拟器 (Phone Mockup) */
.phone-mockup-wrapper {
  display: flex;
  justify-content: center;
  align-items: center;
}

.phone-mockup {
  width: 360px;
  height: 640px;
  background: var(--bg-base);
  border-radius: 46px;
  border: 10px solid #1E282E;
  box-shadow: 0 28px 60px rgba(0, 0, 0, 0.7), 0 0 0 2px var(--border-glass), inset 0 0 10px rgba(0,0,0,0.8);
  position: relative;
  overflow: hidden;
  display: flex;
  flex-direction: column;
}

/* 手机灵动岛与状态栏 */
.phone-status-bar {
  height: 38px;
  padding: 0 22px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-size: 11px;
  font-weight: 600;
  color: var(--text-secondary);
  z-index: 10;
  position: relative;
}

.island-notch {
  width: 90px;
  height: 20px;
  background: #000;
  border-radius: 12px;
  position: absolute;
  top: 8px;
  left: 50%;
  transform: translateX(-50%);
}

.phone-screen {
  flex: 1;
  position: relative;
  overflow: hidden;
  background: var(--bg-base);
  display: flex;
  flex-direction: column;
}

/* 模拟器场景 1：漂流海面捞信 */
.sim-scene {
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.4s ease;
  display: flex;
  flex-direction: column;
  padding: 16px 20px;
}

.sim-scene.active {
  opacity: 1;
  pointer-events: auto;
}

.sim-drift-sea {
  flex: 1;
  position: relative;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
}

.sim-drift-canvas {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
}

.sim-envelope-card {
  width: 140px;
  height: 94px;
  background: var(--bg-card);
  border: 1px solid var(--border-highlight);
  border-radius: 12px;
  position: relative;
  cursor: pointer;
  box-shadow: 0 12px 28px rgba(0, 0, 0, 0.45);
  display: flex;
  align-items: center;
  justify-content: center;
  transition: transform 0.3s ease;
  animation: floatBob 3s ease-in-out infinite;
}

@keyframes floatBob {
  0%, 100% { transform: translateY(0) rotate(2deg); }
  50% { transform: translateY(-8px) rotate(-1deg); }
}

.sim-wax-seal {
  width: 22px;
  height: 22px;
  border-radius: 50%;
  background: var(--accent);
  box-shadow: 0 0 12px var(--accent-glow);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 11px;
  color: #041210;
  font-weight: bold;
}

/* 模拟读信模态弹窗 */
.sim-letter-modal {
  position: absolute;
  inset: 0;
  background: rgba(6, 11, 14, 0.88);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  z-index: 20;
  display: flex;
  flex-direction: column;
  padding: 24px 20px;
  transform: translateY(100%);
  transition: transform 0.4s cubic-bezier(0.16, 1, 0.3, 1);
}

.sim-letter-modal.open {
  transform: translateY(0);
}

.sim-letter-sheet {
  background: rgba(255, 255, 255, 0.08);
  border: 1px solid var(--border-glass);
  border-radius: 16px;
  padding: 20px;
  flex: 1;
  display: flex;
  flex-direction: column;
}

.sim-letter-text {
  font-size: 14px;
  line-height: 1.8;
  color: var(--text-primary);
  flex: 1;
}

.sim-modal-actions {
  display: flex;
  gap: 10px;
  margin-top: 16px;
}

/* 模拟场景 2：树友成长 */
.sim-tree-scene {
  text-align: center;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: space-between;
}

.sim-tree-canvas-box {
  width: 220px;
  height: 220px;
  margin: 10px auto;
  position: relative;
}

#tree-sim-canvas {
  width: 100%;
  height: 100%;
}

.tree-slider-control {
  width: 100%;
  background: var(--bg-card);
  padding: 14px;
  border-radius: 16px;
  border: 1px solid var(--border-glass);
}

.tree-slider-control input[type="range"] {
  width: 100%;
  accent-color: var(--accent);
  cursor: pointer;
}

/* ==========================================================================
   全版本更新日志档案库 · Release Changelog Hub
   ========================================================================== */
.changelog-section {
  padding: 100px 0;
}

.changelog-filter-bar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 16px;
  margin-bottom: 40px;
}

.filter-pills {
  display: flex;
  gap: 10px;
  flex-wrap: wrap;
}

.filter-pill {
  padding: 8px 18px;
  border-radius: var(--radius-pill);
  background: var(--bg-card);
  border: 1px solid var(--border-glass);
  color: var(--text-secondary);
  font-size: 13.5px;
  cursor: pointer;
  transition: var(--transition-smooth);
}

.filter-pill.active, .filter-pill:hover {
  background: var(--accent-subtle);
  color: var(--accent);
  border-color: var(--border-highlight);
}

.search-input-box {
  position: relative;
  min-width: 240px;
}

.search-input-box input {
  width: 100%;
  padding: 9px 16px 9px 36px;
  border-radius: var(--radius-pill);
  background: var(--bg-card);
  border: 1px solid var(--border-glass);
  color: var(--text-primary);
  font-size: 13.5px;
  outline: none;
  transition: var(--transition-smooth);
}

.search-input-box input:focus {
  border-color: var(--border-highlight);
  box-shadow: 0 0 12px var(--accent-glow);
}

.search-input-box svg {
  position: absolute;
  left: 12px;
  top: 50%;
  transform: translateY(-50%);
  color: var(--text-tertiary);
  pointer-events: none;
}

/* 时间轴列表 */
.timeline-list {
  position: relative;
  padding-left: 32px;
}

.timeline-list::before {
  content: '';
  position: absolute;
  left: 7px;
  top: 12px;
  bottom: 12px;
  width: 2px;
  background: linear-gradient(to bottom, var(--accent) 0%, var(--border-glass) 100%);
}

.timeline-item {
  position: relative;
  margin-bottom: 40px;
}

.timeline-dot {
  position: absolute;
  left: -32px;
  top: 6px;
  width: 16px;
  height: 16px;
  border-radius: 50%;
  background: var(--bg-base);
  border: 2px solid var(--accent);
  box-shadow: 0 0 10px var(--accent-glow);
}

.timeline-card {
  background: var(--bg-card);
  border: 1px solid var(--border-glass);
  border-radius: var(--radius-lg);
  padding: 26px 30px;
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  box-shadow: var(--shadow-card);
  transition: var(--transition-smooth);
}

.timeline-card:hover {
  border-color: var(--border-highlight);
  transform: translateX(4px);
}

.timeline-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 12px;
  margin-bottom: 14px;
}

.version-tag {
  display: inline-flex;
  align-items: center;
  gap: 8px;
}

.version-title {
  font-size: 18px;
  font-weight: 600;
  color: var(--text-primary);
}

.version-date {
  font-size: 12.5px;
  color: var(--text-tertiary);
}

.changelog-content {
  font-size: 14.5px;
  color: var(--text-secondary);
  line-height: 1.7;
}

.changelog-content ul {
  padding-left: 20px;
  margin-top: 8px;
}

.changelog-content li {
  margin-bottom: 6px;
}

/* ==========================================================================
   下载与服务端生态 · Download & Deployment
   ========================================================================== */
.download-section {
  padding: 100px 0 140px;
}

.download-card-wrapper {
  background: linear-gradient(135deg, var(--bg-elevated) 0%, rgba(18, 32, 38, 0.8) 100%);
  border: 1px solid var(--border-highlight);
  border-radius: 36px;
  padding: 56px;
  box-shadow: 0 24px 70px -16px rgba(0, 0, 0, 0.7);
  display: grid;
  grid-template-columns: 1.2fr 0.8fr;
  gap: 48px;
  align-items: center;
}

.download-info h2 {
  font-size: clamp(26px, 3.2vw, 38px);
  font-weight: 600;
  margin-bottom: 16px;
}

.download-info p {
  color: var(--text-secondary);
  font-size: 16px;
  margin-bottom: 28px;
  line-height: 1.7;
}

.download-spec-list {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 16px;
  margin-bottom: 36px;
}

.spec-item {
  background: rgba(255, 255, 255, 0.03);
  border: 1px solid var(--border-glass);
  border-radius: var(--radius-md);
  padding: 14px 18px;
}

.spec-label {
  font-size: 12px;
  color: var(--text-tertiary);
  margin-bottom: 4px;
}

.spec-value {
  font-size: 14px;
  font-weight: 600;
  color: var(--text-primary);
}

.qr-code-box {
  background: var(--bg-card);
  border: 1px solid var(--border-glass);
  border-radius: var(--radius-lg);
  padding: 32px;
  text-align: center;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
}

.qr-canvas-holder {
  width: 180px;
  height: 180px;
  background: #FFF;
  border-radius: 12px;
  padding: 10px;
  margin-bottom: 16px;
  box-shadow: 0 8px 24px rgba(0, 0, 0, 0.3);
}

.qr-canvas-holder svg {
  width: 100%;
  height: 100%;
}

.qr-tip {
  font-size: 13px;
  color: var(--text-secondary);
}

/* ==========================================================================
   页脚 Footer
   ========================================================================== */
.site-footer {
  border-top: 1px solid var(--border-glass);
  background: var(--bg-elevated);
  padding: 60px 0 40px;
  font-size: 13px;
  color: var(--text-tertiary);
}

.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr;
  gap: 40px;
  margin-bottom: 48px;
}

.footer-brand h4 {
  font-size: 18px;
  color: var(--text-primary);
  margin-bottom: 12px;
  letter-spacing: 2px;
}

.footer-brand p {
  color: var(--text-secondary);
  max-width: 320px;
  line-height: 1.7;
}

.footer-links h5 {
  font-size: 14px;
  color: var(--text-primary);
  margin-bottom: 16px;
  font-weight: 600;
}

.footer-links ul {
  list-style: none;
}

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

.footer-links a {
  color: var(--text-secondary);
  text-decoration: none;
  transition: color 0.2s ease;
}

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

.footer-bottom {
  display: flex;
  align-items: center;
  justify-content: space-between;
  border-top: 1px solid var(--border-glass);
  padding-top: 24px;
}

/* ==========================================================================
   响应式断点与无障碍
   ========================================================================== */
@media (max-width: 992px) {
  .hero-grid, .sandbox-layout, .download-card-wrapper {
    grid-template-columns: 1fr;
    gap: 40px;
  }
  .nav-menu {
    display: none; /* 移动端可精简为快捷按钮 */
  }
}

@media (max-width: 640px) {
  .sandbox-container, .download-card-wrapper {
    padding: 24px 18px;
  }
  .phone-mockup {
    width: 310px;
    height: 560px;
  }
  .footer-grid {
    grid-template-columns: 1fr;
    gap: 30px;
  }
}

/* 尊重减弱动效偏好 */
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
    scroll-behavior: auto !important;
  }
}