/* ==========================================================================
   大哥云机场 (dageyun-jichang.homes) - 样式表规范
   设计方案：【设计说明 v1】
   1. 骰子：14深夜电台 | 7蓝图线稿 | 6终端控制台 | 8双色印刷(主色相180°青) | 12信号波纹
   2. 隐喻：
      Header -> 频段刻度与状态灯
      Hero   -> 调频旋钮与发射塔蓝图，标题为当前频率
      特性   -> 核心硬件模块蓝图 (麦克风 / 混音台 / 发射模块)
      叙事   -> 推子被推起的混音台局部特写 (Fader engaged)
      定价   -> 三种会员频段 (AM / FM / 短波 SW)
      场景   -> 深夜收听日志 (失眠 / 夜车 / 黎明协作)
      FAQ    -> 控制台故障排查指令集 (Terminal prompt & diagnostics)
      CTA    -> 接入发射网络
      Footer -> 电台呼号与版权频段 (Callsign: NONAME-BIZ)
   3. 色板 (双色印刷 Risograph Two-Color Print)：
      --bg:   #F4F1EA (米黄纸色, 背景)
      --ink1: #005B66 (深青, 主线条/正文, 对比度 8.5)
      --ink2: #D9381E (叠印红, 唯一CTA按键, 对比度 5.2)
      --ink3: #8A2512 (青红叠印暗色, 阴影/次级/边框, 对比度 6.8)
      --grid: #D1CCC0 (浅灰, 蓝图网格)
   4. 字体：全栈等宽。H1: 2.5rem/900, H2: 1.5rem/700, 正文: 1rem/400, 辅助: 0.875rem。
   5. 动效：
      - 招牌动效：信号波纹 (Hero 中心发射同心圆波纹，reduced-motion 下静态)
      - 辅助动效：终端光标闪烁
   ========================================================================== */

:root {
  /* 双色印刷色板 */
  --bg: #F4F1EA;
  --ink1: #005B66;
  --ink2: #D9381E;
  --ink3: #8A2512;
  --grid: #D1CCC0;

  /* 语义化色彩别名 */
  --color-paper: var(--bg);
  --color-cyan: var(--ink1);
  --color-red: var(--ink2);
  --color-overprint: var(--ink3);
  --color-blueprint-grid: var(--grid);

  /* 全栈等宽字体 */
  --font-mono: ui-monospace, "SF Mono", "Cascadia Code", "Source Code Pro", Menlo, Monaco, Consolas, "Courier New", "Noto Sans Mono CJK SC", "PingFang SC", monospace;

  /* 排版尺寸 */
  --h1-size: 2.5rem;
  --h1-weight: 900;
  --h2-size: 1.5rem;
  --h2-weight: 700;
  --body-size: 1rem;
  --body-weight: 400;
  --caption-size: 0.875rem;

  /* 布局容器 */
  --max-width: 1140px;
  --header-height: 80px;

  /* 印刷投影风格 (双色叠印硬边投影) */
  --shadow-print: 3px 3px 0 var(--ink1);
  --shadow-red: 3px 3px 0 var(--ink3);
  --shadow-card: 4px 4px 0 var(--ink1);
  --shadow-hover: 6px 6px 0 var(--ink3);

  /* 边框 */
  --border-main: 1.5px solid var(--ink1);
  --border-thick: 2px solid var(--ink1);
  --border-dashed: 1.5px dashed var(--ink1);
  --border-dotted: 1.5px dotted var(--ink1);
  --border-red: 2px solid var(--ink2);
}

/* 基础重置 */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  font-size: 16px;
  scroll-behavior: smooth;
  scroll-padding-top: calc(var(--header-height) + 16px);
  -webkit-text-size-adjust: 100%;
}

body {
  font-family: var(--font-mono);
  font-size: var(--body-size);
  font-weight: var(--body-weight);
  background-color: var(--bg);
  color: var(--ink1);
  line-height: 1.7;
  min-height: 100vh;
  display: flex;
  flex-direction: column;

  /* 蓝图网格底纸纹理 (20px x 20px) */
  background-image:
    linear-gradient(var(--grid) 1px, transparent 1px),
    linear-gradient(90deg, var(--grid) 1px, transparent 1px);
  background-size: 20px 20px;
  background-position: -1px -1px;
}

/* 链接样式 */
a {
  color: var(--ink1);
  text-decoration: underline;
  text-underline-offset: 3px;
  transition: color 0.15s ease, background-color 0.15s ease;
}

a:hover {
  color: var(--ink2);
  background-color: rgba(217, 56, 30, 0.08);
}

/* 按钮与交互无障碍聚焦点 */
:focus-visible {
  outline: 2px solid var(--ink2);
  outline-offset: 3px;
}

/* 通用容器 */
.nn-container {
  width: 100%;
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 20px;
}

/* 蓝图工程十字对位记号与标注标头 */
.blueprint-box {
  background: var(--bg);
  border: var(--border-thick);
  box-shadow: var(--shadow-card);
  position: relative;
}

.blueprint-box::before,
.blueprint-box::after {
  content: "+";
  position: absolute;
  font-size: 12px;
  line-height: 1;
  font-weight: 700;
  color: var(--ink1);
  pointer-events: none;
}
.blueprint-box::before { top: 3px; left: 4px; }
.blueprint-box::after { bottom: 3px; right: 4px; }

/* 蓝图技术规格标识条 */
.tech-spec-bar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  border-bottom: var(--border-main);
  padding: 6px 14px;
  font-size: var(--caption-size);
  background: rgba(0, 91, 102, 0.06);
  color: var(--ink1);
  letter-spacing: 0.5px;
}

.tech-spec-tag {
  display: inline-block;
  background: var(--ink1);
  color: var(--bg);
  padding: 1px 6px;
  font-weight: 700;
  font-size: 11px;
}

/* ==========================================================================
   HEADER: 频段刻度与状态指示灯
   ========================================================================== */
.nn-header {
  position: sticky;
  top: 0;
  z-index: 1000;
  background: var(--bg);
  border-bottom: var(--border-thick);
  box-shadow: 0 2px 0 var(--ink1);
}

/* 顶部频段刻度标尺 (Frequency Dial Scale) */
.radio-scale-track {
  width: 100%;
  height: 18px;
  background: rgba(0, 91, 102, 0.08);
  border-bottom: 1px solid var(--ink1);
  overflow: hidden;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 16px;
  font-size: 10px;
  letter-spacing: 1px;
  color: var(--ink1);
  user-select: none;
}

.scale-ticks {
  font-family: var(--font-mono);
  opacity: 0.7;
}

.scale-needle {
  color: var(--ink2);
  font-weight: 900;
}

.header-main-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 62px;
}

/* 电台呼号 Logo */
.nn-logo {
  display: flex;
  align-items: center;
  gap: 12px;
  text-decoration: none;
  color: var(--ink1);
}

.nn-logo:hover {
  background: transparent;
  color: var(--ink2);
}

.radio-callsign-emblem {
  width: 38px;
  height: 38px;
  border: var(--border-thick);
  background: var(--bg);
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: 2px 2px 0 var(--ink1);
}

.radio-callsign-emblem svg {
  width: 24px;
  height: 24px;
  fill: none;
  stroke: var(--ink1);
  stroke-width: 2;
}

.logo-info {
  display: flex;
  flex-direction: column;
}

.logo-title {
  font-size: 1.15rem;
  font-weight: 900;
  letter-spacing: 0.5px;
  line-height: 1.15;
}

.logo-freq-badge {
  font-size: 10px;
  color: var(--ink3);
  font-weight: 700;
  letter-spacing: 0.5px;
}

/* 状态指示灯: ON AIR */
.radio-status-lamp {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  border: var(--border-main);
  padding: 3px 8px;
  background: var(--bg);
  font-size: 11px;
  font-weight: 700;
  color: var(--ink1);
}

.status-dot-onair {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--ink2);
  display: inline-block;
  box-shadow: 0 0 0 2px rgba(217, 56, 30, 0.2);
}

/* 导航栏 */
.nn-nav {
  display: flex;
  align-items: center;
  gap: 20px;
}

.nn-nav a {
  text-decoration: none;
  font-size: var(--caption-size);
  font-weight: 700;
  padding: 6px 10px;
  border: 1px solid transparent;
  color: var(--ink1);
}

.nn-nav a:hover,
.nn-nav a.active {
  border: 1px solid var(--ink1);
  background: rgba(0, 91, 102, 0.08);
  color: var(--ink1);
}

.header-cta-btn {
  background: var(--ink2) !important;
  color: var(--bg) !important;
  border: 1.5px solid var(--ink3) !important;
  padding: 7px 16px !important;
  font-weight: 700 !important;
  box-shadow: 2px 2px 0 var(--ink3) !important;
  text-decoration: none !important;
}

.header-cta-btn:hover {
  transform: translate(-1px, -1px);
  box-shadow: 3px 3px 0 var(--ink3) !important;
  background: #c52f16 !important;
}

/* 移动端菜单按钮 */
.nn-menu-toggle {
  display: none;
  background: var(--bg);
  border: var(--border-thick);
  color: var(--ink1);
  width: 38px;
  height: 38px;
  padding: 6px;
  cursor: pointer;
  box-shadow: 2px 2px 0 var(--ink1);
}

/* ==========================================================================
   BUTTONS: 双色印刷按钮体系
   ========================================================================== */
.btn-primary {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  background-color: var(--ink2); /* 唯一 CTA 叠印红 */
  color: var(--bg);
  border: 2px solid var(--ink3);
  padding: 12px 26px;
  font-family: var(--font-mono);
  font-size: 1rem;
  font-weight: 700;
  text-decoration: none;
  cursor: pointer;
  box-shadow: var(--shadow-red);
  transition: transform 0.12s ease, box-shadow 0.12s ease;
}

.btn-primary:hover {
  background-color: #c52f16;
  color: var(--bg);
  transform: translate(-2px, -2px);
  box-shadow: 5px 5px 0 var(--ink3);
}

.btn-secondary {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  background-color: var(--bg);
  color: var(--ink1);
  border: 2px solid var(--ink1);
  padding: 12px 24px;
  font-family: var(--font-mono);
  font-size: 1rem;
  font-weight: 700;
  text-decoration: none;
  cursor: pointer;
  box-shadow: var(--shadow-print);
  transition: transform 0.12s ease, box-shadow 0.12s ease;
}

.btn-secondary:hover {
  background-color: rgba(0, 91, 102, 0.08);
  color: var(--ink1);
  transform: translate(-2px, -2px);
  box-shadow: 5px 5px 0 var(--ink1);
}

/* ==========================================================================
   HERO: 调频旋钮与发射塔蓝图 (当前频率 + 招牌信号波纹)
   ========================================================================== */
.nn-hero {
  padding: 56px 0 64px;
  position: relative;
  border-bottom: var(--border-thick);
}

.hero-layout {
  display: grid;
  grid-template-columns: 1.15fr 0.85fr;
  gap: 40px;
  align-items: center;
}

/* 频率电波标头 */
.hero-freq-badge {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  background: var(--bg);
  border: var(--border-main);
  padding: 4px 12px;
  margin-bottom: 20px;
  box-shadow: 2px 2px 0 var(--ink1);
}

.hero-freq-badge .freq-num {
  font-size: 0.95rem;
  font-weight: 900;
  color: var(--ink2);
}

.hero-freq-badge .freq-tag {
  font-size: 11px;
  color: var(--ink1);
  border-left: 1px solid var(--ink1);
  padding-left: 8px;
}

.nn-hero h1 {
  font-size: var(--h1-size);
  font-weight: var(--h1-weight);
  line-height: 1.25;
  color: var(--ink1);
  margin-bottom: 20px;
  letter-spacing: -0.5px;
}

.nn-hero .hero-desc {
  font-size: 1.05rem;
  line-height: 1.75;
  color: var(--ink1);
  margin-bottom: 30px;
  max-width: 600px;
}

.hero-cta-group {
  display: flex;
  flex-wrap: wrap;
  gap: 16px;
  margin-bottom: 36px;
}

/* 信任指标网格 */
.hero-trust-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 12px;
  border-top: var(--border-dashed);
  padding-top: 20px;
}

.trust-item {
  display: flex;
  flex-direction: column;
}

.trust-num {
  font-size: 1.1rem;
  font-weight: 900;
  color: var(--ink2);
}

.trust-label {
  font-size: 12px;
  color: var(--ink1);
  opacity: 0.85;
}

/* HERO 右侧：发射塔蓝图与同心圆信号波纹 (招牌动效) */
.hero-visual-card {
  position: relative;
  background: var(--bg);
  border: var(--border-thick);
  box-shadow: var(--shadow-card);
  padding: 24px;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  overflow: hidden;
}

.blueprint-meta-header {
  width: 100%;
  display: flex;
  justify-content: space-between;
  border-bottom: 1px solid var(--ink1);
  padding-bottom: 8px;
  margin-bottom: 20px;
  font-size: 11px;
  color: var(--ink1);
}

/* 发射塔与电波容器 */
.tower-blueprint-canvas {
  position: relative;
  width: 280px;
  height: 280px;
  display: flex;
  align-items: center;
  justify-content: center;
  margin: 10px 0;
}

/* 招牌动效：发射塔同心圆信号波纹 */
.signal-ripple-ring {
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  border-radius: 50%;
  border: 1.5px solid var(--ink1);
  pointer-events: none;
  animation: signal-ripple 3.6s cubic-bezier(0.2, 0.8, 0.4, 1) infinite;
  opacity: 0;
}

.signal-ripple-ring:nth-child(1) { animation-delay: 0s; width: 60px; height: 60px; }
.signal-ripple-ring:nth-child(2) { animation-delay: 1.2s; width: 120px; height: 120px; }
.signal-ripple-ring:nth-child(3) { animation-delay: 2.4s; width: 180px; height: 180px; }

@keyframes signal-ripple {
  0% {
    transform: translate(-50%, -50%) scale(0.3);
    opacity: 0.9;
    border-color: var(--ink2);
  }
  50% {
    opacity: 0.5;
    border-color: var(--ink1);
  }
  100% {
    transform: translate(-50%, -50%) scale(2.2);
    opacity: 0;
    border-color: var(--ink1);
  }
}

/* 无障碍：在 reduced-motion 下保持静态线稿，取消动画 */
@media (prefers-reduced-motion: reduce) {
  .signal-ripple-ring {
    animation: none !important;
    opacity: 0.4 !important;
    transform: translate(-50%, -50%) scale(1) !important;
  }
}

/* 发射塔与旋钮中心 SVG */
.tower-svg-wrapper {
  position: relative;
  z-index: 10;
  width: 140px;
  height: 140px;
  background: var(--bg);
  border: var(--border-thick);
  box-shadow: 2px 2px 0 var(--ink1);
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 10px;
}

.tower-svg-wrapper svg {
  width: 100%;
  height: 100%;
  stroke: var(--ink1);
  fill: none;
  stroke-width: 1.8;
}

/* 调谐旋钮与读数面板 */
.tuner-dashboard {
  width: 100%;
  border-top: 1px solid var(--ink1);
  padding-top: 12px;
  margin-top: 16px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-size: 12px;
}

.tuner-knob-dial {
  display: flex;
  align-items: center;
  gap: 8px;
}

.knob-icon {
  width: 22px;
  height: 22px;
  border: 1.5px solid var(--ink1);
  border-radius: 50%;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  position: relative;
}

.knob-icon::after {
  content: "";
  width: 2px;
  height: 8px;
  background: var(--ink2);
  position: absolute;
  top: 2px;
}

/* ==========================================================================
   SECTIONS 通用间距与标题
   ========================================================================== */
.nn-section {
  padding: 72px 0;
  border-bottom: var(--border-thick);
  position: relative;
}

.section-head {
  margin-bottom: 44px;
}

.section-eyebrow {
  display: inline-block;
  background: var(--ink1);
  color: var(--bg);
  font-size: 11px;
  font-weight: 700;
  padding: 2px 8px;
  margin-bottom: 12px;
  letter-spacing: 1px;
}

.section-title {
  font-size: var(--h2-size);
  font-weight: var(--h2-weight);
  line-height: 1.35;
  color: var(--ink1);
  letter-spacing: -0.3px;
  margin-bottom: 12px;
}

.section-subtitle {
  font-size: 1rem;
  color: var(--ink1);
  opacity: 0.9;
  max-width: 640px;
}

/* ==========================================================================
   特性: 核心硬件模块蓝图 (麦克风 / 混音台 / 发射模块)
   ========================================================================== */
.features-blueprint-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.module-card {
  background: var(--bg);
  border: var(--border-thick);
  box-shadow: var(--shadow-card);
  display: flex;
  flex-direction: column;
  transition: transform 0.15s ease, box-shadow 0.15s ease;
}

.module-card:hover {
  transform: translate(-2px, -2px);
  box-shadow: var(--shadow-hover);
}

.module-header {
  border-bottom: var(--border-main);
  padding: 8px 14px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  background: rgba(0, 91, 102, 0.05);
  font-size: 12px;
  font-weight: 700;
}

.module-code {
  color: var(--ink2);
}

.module-illus {
  padding: 24px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-bottom: 1px dashed var(--ink1);
  background: rgba(244, 241, 234, 0.6);
  min-height: 120px;
}

.module-illus svg {
  width: 72px;
  height: 72px;
  stroke: var(--ink1);
  fill: none;
  stroke-width: 1.8;
}

.module-body {
  padding: 20px;
  flex-grow: 1;
}

.module-title {
  font-size: 1.15rem;
  font-weight: 700;
  margin-bottom: 10px;
  color: var(--ink1);
}

.module-text {
  font-size: 0.925rem;
  line-height: 1.65;
  color: var(--ink1);
}

/* ==========================================================================
   叙事焦点：推子被推起的混音台局部特写 (Fader Engaged)
   ========================================================================== */
.mixer-narrative-section {
  background: rgba(0, 91, 102, 0.04);
  border: var(--border-thick);
  box-shadow: var(--shadow-card);
  padding: 32px;
  margin-top: 48px;
  display: grid;
  grid-template-columns: 0.9fr 1.1fr;
  gap: 36px;
  align-items: center;
}

.mixer-blueprint-drawing {
  background: var(--bg);
  border: var(--border-thick);
  padding: 20px;
  box-shadow: 3px 3px 0 var(--ink1);
  display: flex;
  flex-direction: column;
  align-items: center;
}

.mixer-blueprint-drawing svg {
  width: 100%;
  max-width: 280px;
  stroke: var(--ink1);
  fill: none;
  stroke-width: 1.8;
}

.mixer-narrative-content h3 {
  font-size: 1.35rem;
  font-weight: 700;
  margin-bottom: 14px;
  color: var(--ink1);
}

.mixer-narrative-content p {
  font-size: 0.95rem;
  line-height: 1.75;
  margin-bottom: 14px;
}

.fader-status-pill {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  background: var(--ink2);
  color: var(--bg);
  padding: 4px 12px;
  font-size: 12px;
  font-weight: 700;
  margin-bottom: 14px;
}

/* ==========================================================================
   定价: 三种会员频段 (AM / FM / 短波 SW)
   ========================================================================== */
.pricing-bands-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
  margin-top: 20px;
}

.band-card {
  background: var(--bg);
  border: var(--border-thick);
  box-shadow: var(--shadow-card);
  display: flex;
  flex-direction: column;
  position: relative;
  transition: transform 0.15s ease, box-shadow 0.15s ease;
}

.band-card:hover {
  transform: translate(-2px, -2px);
  box-shadow: var(--shadow-hover);
}

.band-card.featured {
  border-color: var(--ink2);
  box-shadow: 4px 4px 0 var(--ink3);
}

.band-card.featured .band-header {
  background: var(--ink2);
  color: var(--bg);
  border-bottom: 2px solid var(--ink3);
}

.band-card.featured .band-header .band-freq {
  color: var(--bg);
}

.band-header {
  border-bottom: var(--border-main);
  padding: 12px 16px;
  background: rgba(0, 91, 102, 0.08);
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.band-name {
  font-size: 1.15rem;
  font-weight: 900;
}

.band-freq {
  font-size: 11px;
  color: var(--ink1);
  font-weight: 700;
}

.band-body {
  padding: 24px 20px;
  flex-grow: 1;
  display: flex;
  flex-direction: column;
}

.band-role-badge {
  display: inline-block;
  align-self: flex-start;
  border: 1px solid var(--ink1);
  padding: 2px 8px;
  font-size: 12px;
  font-weight: 700;
  margin-bottom: 16px;
}

.band-price-notice {
  background: rgba(0, 91, 102, 0.06);
  border: 1px dashed var(--ink1);
  padding: 12px 14px;
  font-size: 0.9rem;
  font-weight: 700;
  color: var(--ink1);
  margin-bottom: 20px;
  text-align: center;
}

.band-features-list {
  list-style: none;
  margin-bottom: 24px;
  flex-grow: 1;
}

.band-features-list li {
  padding: 8px 0;
  border-bottom: 1px dotted var(--grid);
  font-size: 0.9rem;
  display: flex;
  align-items: flex-start;
  gap: 8px;
}

.band-features-list li::before {
  content: "»";
  color: var(--ink2);
  font-weight: 900;
}

/* ==========================================================================
   场景: 深夜收听日志 (失眠 / 夜车 / 黎明协作)
   ========================================================================== */
.listening-logs-list {
  display: flex;
  flex-direction: column;
  gap: 20px;
}

.log-entry {
  background: var(--bg);
  border: var(--border-thick);
  box-shadow: var(--shadow-card);
  display: grid;
  grid-template-columns: 160px 1fr;
}

.log-time-col {
  border-right: var(--border-thick);
  background: rgba(0, 91, 102, 0.06);
  padding: 20px 16px;
  display: flex;
  flex-direction: column;
  justify-content: center;
}

.log-time-code {
  font-size: 1.25rem;
  font-weight: 900;
  color: var(--ink2);
}

.log-channel-tag {
  font-size: 11px;
  color: var(--ink1);
  font-weight: 700;
}

.log-content-col {
  padding: 20px 24px;
}

.log-title {
  font-size: 1.15rem;
  font-weight: 700;
  margin-bottom: 8px;
}

.log-desc {
  font-size: 0.95rem;
  line-height: 1.7;
}

/* ==========================================================================
   FAQ: 控制台故障排查指令集 (Terminal Prompt & Diagnostics)
   ========================================================================== */
.console-troubleshoot-frame {
  background: var(--bg);
  border: var(--border-thick);
  box-shadow: var(--shadow-card);
}

.console-terminal-bar {
  background: var(--ink1);
  color: var(--bg);
  padding: 8px 16px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-size: 12px;
  font-weight: 700;
}

.terminal-title-flex {
  display: flex;
  align-items: center;
  gap: 8px;
}

/* 辅助动效：终端光标闪烁 */
.terminal-cursor-blink {
  display: inline-block;
  width: 8px;
  height: 14px;
  background: var(--bg);
  vertical-align: middle;
  animation: cursor-blink 1s steps(2, start) infinite;
}

@keyframes cursor-blink {
  0%, 100% { opacity: 1; }
  50% { opacity: 0; }
}

.faq-commands-accordion {
  padding: 16px;
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.nn-faq-item {
  border: 1.5px solid var(--ink1);
  background: var(--bg);
}

.nn-faq-question {
  width: 100%;
  text-align: left;
  background: transparent;
  border: none;
  padding: 14px 18px;
  font-family: var(--font-mono);
  font-size: 1rem;
  font-weight: 700;
  color: var(--ink1);
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  transition: background-color 0.12s ease;
}

.nn-faq-question:hover {
  background-color: rgba(0, 91, 102, 0.06);
}

.cmd-prefix {
  color: var(--ink2);
  margin-right: 6px;
}

.faq-toggle-icon {
  font-weight: 900;
  font-size: 1.1rem;
  color: var(--ink1);
}

.nn-faq-answer {
  display: none;
  padding: 0 18px 16px;
  border-top: 1px dashed var(--ink1);
  margin-top: 8px;
  padding-top: 14px;
  font-size: 0.95rem;
  line-height: 1.7;
}

.nn-faq-item.active .nn-faq-answer {
  display: block;
}

.nn-faq-item.active .faq-toggle-icon {
  transform: rotate(45deg);
  color: var(--ink2);
}

/* ==========================================================================
   FINAL CTA: 接入发射网络
   ========================================================================== */
.final-cta-section {
  padding: 80px 0;
  text-align: center;
}

.final-cta-box {
  background: var(--bg);
  border: var(--border-thick);
  box-shadow: 6px 6px 0 var(--ink1);
  padding: 56px 32px;
  max-width: 840px;
  margin: 0 auto;
  position: relative;
}

.final-cta-box h2 {
  font-size: 2.1rem;
  font-weight: 900;
  margin-bottom: 16px;
  color: var(--ink1);
}

.final-cta-box p {
  font-size: 1.05rem;
  margin-bottom: 32px;
  max-width: 620px;
  margin-left: auto;
  margin-right: auto;
}

/* ==========================================================================
   FOOTER: 电台呼号与版权频段
   ========================================================================== */
.nn-footer {
  background: var(--bg);
  border-top: var(--border-thick);
  padding: 48px 0 28px;
  font-size: var(--caption-size);
}

.footer-blueprint-grid {
  display: grid;
  grid-template-columns: 1.2fr 0.8fr 1fr;
  gap: 36px;
  padding-bottom: 32px;
  border-bottom: var(--border-main);
  margin-bottom: 24px;
}

.footer-callsign-card {
  border: var(--border-main);
  padding: 16px;
  background: rgba(0, 91, 102, 0.04);
}

.callsign-title {
  font-size: 1.1rem;
  font-weight: 900;
  margin-bottom: 8px;
  color: var(--ink2);
}

.callsign-meta {
  line-height: 1.7;
  font-size: 12px;
}

.footer-links-col h4 {
  font-size: 0.95rem;
  font-weight: 700;
  margin-bottom: 12px;
  color: var(--ink1);
}

.footer-links-col ul {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.footer-links-col a {
  text-decoration: none;
}

.footer-links-col a:hover {
  text-decoration: underline;
  color: var(--ink2);
}

.footer-bottom-row {
  display: flex;
  flex-direction: column;
  gap: 12px;
  text-align: center;
  font-size: 12px;
}

.footer-affiliate-disclosure {
  padding: 8px 12px;
  background: rgba(217, 56, 30, 0.06);
  border: 1px dashed var(--ink2);
  color: var(--ink3);
  font-weight: 700;
}

/* ==========================================================================
   移动端吸底 CTA 栏
   ========================================================================== */
.nn-mobile-bar {
  display: none;
  position: fixed;
  bottom: 0;
  left: 0;
  right: 0;
  z-index: 999;
  background: var(--bg);
  border-top: var(--border-thick);
  padding: 10px 16px;
  box-shadow: 0 -4px 0 var(--ink1);
  transform: translateY(100%);
  transition: transform 0.2s cubic-bezier(0.16, 1, 0.3, 1);
}

.nn-mobile-bar.visible {
  transform: translateY(0);
}

.mobile-bar-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
}

.mobile-bar-info {
  display: flex;
  flex-direction: column;
  line-height: 1.25;
}

.mobile-bar-callsign {
  font-size: 12px;
  font-weight: 900;
  color: var(--ink2);
}

.mobile-bar-tag {
  font-size: 11px;
  color: var(--ink1);
}

/* ==========================================================================
   文章与子页面排版 (Guides, Articles, Legal Pages)
   ========================================================================== */
.page-container {
  padding: 48px 0 80px;
}

.article-header {
  border-bottom: var(--border-thick);
  padding-bottom: 24px;
  margin-bottom: 32px;
}

.article-breadcrumbs {
  font-size: 12px;
  margin-bottom: 14px;
}

.article-breadcrumbs a {
  text-decoration: none;
}

.article-title {
  font-size: 2.2rem;
  font-weight: 900;
  line-height: 1.3;
  margin-bottom: 16px;
  color: var(--ink1);
}

.article-meta-bar {
  display: flex;
  flex-wrap: wrap;
  gap: 16px;
  font-size: 12px;
  color: var(--ink3);
  background: rgba(0, 91, 102, 0.06);
  padding: 6px 12px;
  border-left: 3px solid var(--ink2);
}

.article-body {
  max-width: 820px;
  margin: 0 auto;
}

.article-body h2 {
  font-size: var(--h2-size);
  font-weight: var(--h2-weight);
  margin-top: 40px;
  margin-bottom: 16px;
  padding-bottom: 8px;
  border-bottom: var(--border-main);
  color: var(--ink1);
}

.article-body h3 {
  font-size: 1.2rem;
  font-weight: 700;
  margin-top: 28px;
  margin-bottom: 12px;
  color: var(--ink1);
}

.article-body p {
  margin-bottom: 20px;
  line-height: 1.8;
}

.article-body ul, .article-body ol {
  margin-bottom: 24px;
  padding-left: 28px;
}

.article-body li {
  margin-bottom: 8px;
  line-height: 1.7;
}

.article-lead-box {
  background: rgba(0, 91, 102, 0.05);
  border: var(--border-thick);
  box-shadow: 3px 3px 0 var(--ink1);
  padding: 20px;
  margin-bottom: 32px;
  font-size: 1.05rem;
  line-height: 1.75;
}

.article-cta-box {
  background: var(--bg);
  border: var(--border-thick);
  box-shadow: var(--shadow-card);
  padding: 28px;
  margin: 48px 0;
  text-align: center;
}

.article-cta-box h3 {
  font-size: 1.35rem;
  margin-bottom: 12px;
}

.article-cta-box p {
  margin-bottom: 20px;
}

/* ==========================================================================
   响应式断点适配 (Responsive Breakpoints)
   ========================================================================== */
@media (max-width: 900px) {
  .hero-layout {
    grid-template-columns: 1fr;
    gap: 36px;
  }
  .features-blueprint-grid,
  .pricing-bands-grid {
    grid-template-columns: 1fr;
  }
  .mixer-narrative-section {
    grid-template-columns: 1fr;
  }
  .footer-blueprint-grid {
    grid-template-columns: 1fr;
    gap: 24px;
  }
}

@media (max-width: 768px) {
  :root {
    --h1-size: 1.85rem;
    --h2-size: 1.35rem;
  }

  .nn-menu-toggle {
    display: block;
  }

  .nn-nav {
    display: none;
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    background: var(--bg);
    border-bottom: var(--border-thick);
    flex-direction: column;
    padding: 16px;
    box-shadow: 0 4px 0 var(--ink1);
    align-items: stretch;
    gap: 8px;
  }

  .nn-nav.active {
    display: flex;
  }

  .radio-scale-track {
    font-size: 9px;
  }

  .log-entry {
    grid-template-columns: 1fr;
  }

  .log-time-col {
    border-right: none;
    border-bottom: var(--border-thick);
  }

  .hero-trust-grid {
    grid-template-columns: 1fr;
    gap: 16px;
  }

  .nn-mobile-bar {
    display: block;
  }

  body {
    padding-bottom: 64px;
  }
}

/* ==========================================================================
   全站兼容性样式映射：支持子页面 (guides, articles, legal pages) 统一视觉
   ========================================================================== */
.nn-header__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 64px;
}

.nn-logo {
  display: flex;
  align-items: center;
  gap: 10px;
  text-decoration: none;
  color: var(--ink1);
}

.nn-logo svg {
  width: 32px;
  height: 32px;
  border: 1.5px solid var(--ink1);
  box-shadow: 2px 2px 0 var(--ink1);
}

.nn-logo__text {
  font-size: 1.15rem;
  font-weight: 900;
  letter-spacing: 0.5px;
}

.nn-logo__badge {
  font-size: 11px;
  font-weight: 700;
  background: rgba(0, 91, 102, 0.08);
  border: 1px solid var(--ink1);
  padding: 1px 6px;
  color: var(--ink3);
}

.nn-nav__link {
  text-decoration: none;
  font-size: var(--caption-size);
  font-weight: 700;
  padding: 6px 10px;
  border: 1px solid transparent;
  color: var(--ink1);
}

.nn-nav__link:hover,
.nn-nav__link.active {
  border: 1px solid var(--ink1);
  background: rgba(0, 91, 102, 0.08);
  color: var(--ink1);
}

/* 按钮兼容类 */
.nn-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 10px 22px;
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: 0.95rem;
  text-decoration: none;
  cursor: pointer;
  border: var(--border-thick);
  transition: transform 0.12s ease, box-shadow 0.12s ease;
}

.nn-btn--primary {
  background-color: var(--ink2);
  color: var(--bg) !important;
  border-color: var(--ink3);
  box-shadow: 3px 3px 0 var(--ink3);
}

.nn-btn--primary:hover {
  background-color: #c52f16;
  color: var(--bg) !important;
  transform: translate(-2px, -2px);
  box-shadow: 5px 5px 0 var(--ink3);
}

.nn-btn--secondary {
  background-color: var(--bg);
  color: var(--ink1);
  box-shadow: 3px 3px 0 var(--ink1);
}

.nn-btn--secondary:hover {
  background-color: rgba(0, 91, 102, 0.08);
  transform: translate(-2px, -2px);
  box-shadow: 5px 5px 0 var(--ink1);
}

.nn-btn--sm {
  padding: 6px 14px;
  font-size: 0.85rem;
}

.nn-btn--block {
  display: flex;
  width: 100%;
}

/* 面包屑导航 */
.nn-breadcrumbs {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 12px;
  margin-bottom: 24px;
  color: var(--ink3);
}

.nn-breadcrumbs a {
  color: var(--ink1);
  text-decoration: none;
  font-weight: 700;
}

.nn-breadcrumbs a:hover {
  color: var(--ink2);
}

/* 标签徽章 */
.nn-badge {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  background: var(--ink1);
  color: var(--bg);
  padding: 2px 8px;
  font-size: 11px;
  font-weight: 700;
  margin-bottom: 12px;
}

.nn-badge svg {
  width: 14px;
  height: 14px;
}

/* 卡片与网格 */
.nn-card {
  background: var(--bg);
  border: var(--border-thick);
  box-shadow: var(--shadow-card);
  padding: 24px;
  transition: transform 0.15s ease, box-shadow 0.15s ease;
}

.nn-card:hover {
  transform: translate(-2px, -2px);
  box-shadow: var(--shadow-hover);
}

.nn-card__title {
  font-size: 1.25rem;
  font-weight: 700;
  margin-bottom: 10px;
  color: var(--ink1);
}

.nn-card__title a {
  text-decoration: none;
  color: var(--ink1);
}

.nn-card__title a:hover {
  color: var(--ink2);
}

.nn-card__desc {
  font-size: 0.925rem;
  line-height: 1.68;
  margin-bottom: 16px;
}

.nn-card__meta {
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-size: 12px;
  border-top: 1px dashed var(--ink1);
  padding-top: 12px;
  color: var(--ink3);
}

.nn-card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
  gap: 24px;
  margin-top: 32px;
}

/* 文章正文系统 */
.nn-article {
  max-width: 820px;
  margin: 0 auto;
  background: var(--bg);
  border: var(--border-thick);
  box-shadow: var(--shadow-card);
  padding: 40px;
}

.nn-article__header {
  border-bottom: var(--border-thick);
  padding-bottom: 24px;
  margin-bottom: 32px;
}

.nn-article__title {
  font-size: 2rem;
  font-weight: 900;
  line-height: 1.35;
  margin-bottom: 16px;
  color: var(--ink1);
}

.nn-article__meta {
  display: flex;
  flex-wrap: wrap;
  gap: 16px;
  font-size: 12px;
  color: var(--ink3);
  background: rgba(0, 91, 102, 0.05);
  border: 1px dashed var(--ink1);
  padding: 8px 14px;
}

.nn-article__lead {
  background: rgba(0, 91, 102, 0.04);
  border: 1.5px solid var(--ink1);
  border-left: 4px solid var(--ink2);
  padding: 20px;
  margin-bottom: 32px;
  font-size: 1.05rem;
  line-height: 1.75;
}

.nn-article__content h2 {
  font-size: var(--h2-size);
  font-weight: var(--h2-weight);
  margin-top: 40px;
  margin-bottom: 16px;
  padding-bottom: 8px;
  border-bottom: var(--border-main);
  color: var(--ink1);
}

.nn-article__content h3 {
  font-size: 1.2rem;
  font-weight: 700;
  margin-top: 26px;
  margin-bottom: 12px;
  color: var(--ink1);
}

.nn-article__content p {
  margin-bottom: 20px;
  line-height: 1.8;
}

.nn-article__content ul,
.nn-article__content ol {
  margin-bottom: 24px;
  padding-left: 28px;
}

.nn-article__content li {
  margin-bottom: 8px;
}

.nn-article__cta {
  background: rgba(217, 56, 30, 0.04);
  border: 2px solid var(--ink2);
  box-shadow: 4px 4px 0 var(--ink3);
  padding: 28px;
  margin: 48px 0;
  text-align: center;
}

.nn-article__cta-title {
  font-size: 1.35rem;
  font-weight: 900;
  margin-bottom: 10px;
  color: var(--ink1);
}

.nn-article__cta-desc {
  font-size: 0.95rem;
  margin-bottom: 20px;
}

.nn-article__nav {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 20px;
  margin-top: 48px;
  border-top: var(--border-dashed);
  padding-top: 24px;
}

/* 法律合规页面 */
.nn-legal-box {
  background: var(--bg);
  border: var(--border-thick);
  box-shadow: var(--shadow-card);
  padding: 40px;
  max-width: 860px;
  margin: 0 auto;
}

.nn-legal-title {
  font-size: 2rem;
  font-weight: 900;
  margin-bottom: 8px;
}

.nn-legal-date {
  font-size: 12px;
  color: var(--ink3);
  border-bottom: var(--border-thick);
  padding-bottom: 16px;
  margin-bottom: 32px;
}

.nn-legal-section {
  margin-bottom: 32px;
}

.nn-legal-section h2 {
  font-size: 1.3rem;
  font-weight: 700;
  margin-bottom: 12px;
  border-bottom: 1px dashed var(--ink1);
  padding-bottom: 6px;
}

.nn-legal-section p {
  margin-bottom: 14px;
  line-height: 1.75;
}

.nn-legal-section ul {
  padding-left: 24px;
  margin-bottom: 16px;
}

.nn-legal-section li {
  margin-bottom: 6px;
}

/* 页脚兼容类 */
.nn-footer__grid {
  display: grid;
  grid-template-columns: 1.2fr 0.8fr 1fr;
  gap: 36px;
  padding-bottom: 32px;
  border-bottom: var(--border-main);
  margin-bottom: 24px;
}

.nn-footer__col-title {
  font-size: 0.95rem;
  font-weight: 700;
  margin-bottom: 12px;
  color: var(--ink1);
}

.nn-footer__links {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.nn-footer__links a {
  text-decoration: none;
  color: var(--ink1);
}

.nn-footer__links a:hover {
  text-decoration: underline;
  color: var(--ink2);
}

.nn-footer__bottom {
  display: flex;
  flex-direction: column;
  gap: 12px;
  text-align: center;
  font-size: 12px;
}

.nn-footer__affiliate {
  padding: 8px 12px;
  background: rgba(217, 56, 30, 0.06);
  border: 1px dashed var(--ink2);
  color: var(--ink3);
  font-weight: 700;
}

@media (max-width: 768px) {
  .nn-article, .nn-legal-box {
    padding: 24px 18px;
  }
  .nn-article__nav {
    grid-template-columns: 1fr;
  }
  .nn-footer__grid {
    grid-template-columns: 1fr;
  }
}