/* ============================================================
   星联车载官网样式
   ------------------------------------------------------------
   修改配色：只需调整下方 :root 中的变量
   修改某区块样式：搜索对应注释（如「核心优势」）
   ============================================================ */

/* ===== 主题变量（改这里即可全站换肤） ===== */
:root {
  --primary: #ff6900;        /* 主色：小米橙 */
  --primary-light: #ff8c42;
  --accent: #ffaa00;         /* 强调色：亮橙黄 */
  --accent-2: #e65100;       /* 辅助色：深橙 */

  --bg-dark: #0b1220;        /* 深色区块背景 */
  --bg-dark-2: #101a2e;
  --bg-page: #ffffff;        /* 浅色区块背景 */
  --bg-gray: #f4f6fa;        /* 灰色区块背景 */

  --text-dark: #0f172a;      /* 浅底文字 */
  --text-light: #e6edf7;     /* 深底文字 */
  --text-muted: #64748b;     /* 次要文字（浅底） */
  --text-muted-l: #94a3b8;   /* 次要文字（深底） */

  --card-bg: #ffffff;
  --card-bg-dark: rgba(255,255,255,0.05);

  --border: #e2e8f0;
  --border-dark: rgba(255,255,255,0.1);

  --radius: 14px;
  --radius-sm: 10px;
  --shadow: 0 8px 30px rgba(15, 23, 42, 0.08);
  --shadow-hover: 0 16px 40px rgba(15, 23, 42, 0.14);

  --container: 1140px;
  --transition: 0.3s ease;
}

/* ===== Reset ===== */
*, *::before, *::after { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC",
               "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  color: var(--text-dark);
  background: var(--bg-page);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
}
a { text-decoration: none; color: inherit; }
ul { list-style: none; }
img { max-width: 100%; display: block; }
button, input, textarea { font-family: inherit; outline: none; }
button { cursor: pointer; border: none; background: none; }

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

/* ============================================================
   导航栏
   ============================================================ */
.header {
  position: fixed;
  top: 0; left: 0; right: 0;
  z-index: 100;
  background: rgba(250, 247, 242, 0.92);  /* 米白色 */
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border);
  transition: background var(--transition);
}
.header__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 92px;
}
.logo { display: flex; align-items: center; gap: 10px; }
.logo__img { height: 72px; max-width: 260px; width: auto; object-fit: contain; display: block; }
.logo--footer .logo__img { height: 56px; max-width: 200px; }

.nav { display: flex; align-items: center; gap: 4px; }
.nav__link {
  padding: 8px 14px;
  font-size: 14px;
  color: var(--text-muted);
  border-radius: 8px;
  transition: all var(--transition);
}
.nav__link:hover { color: var(--text-dark); background: rgba(15, 23, 42, 0.06); }
.nav__link--active { color: var(--text-dark); }
.nav__link--cta {
  color: #fff;
  background: linear-gradient(135deg, var(--primary), var(--accent));
  font-weight: 600;
  margin-left: 8px;
}
.nav__link--cta:hover {
  transform: translateY(-1px);
  box-shadow: 0 6px 20px rgba(255, 105, 0, 0.35);
}

/* 服务支持下拉菜单（与页脚「服务支持」栏目同步） */
.nav__item { position: relative; }
.nav__link--drop {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  background: none;
  border: none;
  cursor: pointer;
  font: inherit;
  letter-spacing: inherit;
}
.nav__link--drop::after {
  content: '▾';
  font-size: 11px;
  opacity: 0.7;
  transition: transform var(--transition);
}
.nav__item:hover .nav__link--drop::after,
.nav__item.open .nav__link--drop::after { transform: rotate(180deg); }

.nav__dropdown {
  position: absolute;
  top: calc(100% + 10px);
  left: 50%;
  transform: translateX(-50%) translateY(-6px);
  min-width: 200px;
  background: #fff;
  border: 1px solid var(--border);
  border-radius: 14px;
  box-shadow: 0 16px 40px rgba(15, 23, 42, 0.16);
  padding: 8px;
  display: flex;
  flex-direction: column;
  gap: 2px;
  opacity: 0;
  visibility: hidden;
  transition: all .28s cubic-bezier(.22, .61, .36, 1);
  z-index: 130;
}
.nav__dropdown::before {
  content: '';
  position: absolute;
  top: -6px;
  left: 50%;
  transform: translateX(-50%) rotate(45deg);
  width: 12px; height: 12px;
  background: #fff;
  border-left: 1px solid var(--border);
  border-top: 1px solid var(--border);
  border-radius: 3px;
}
.nav__item:hover .nav__dropdown,
.nav__item:focus-within .nav__dropdown,
.nav__item.open .nav__dropdown {
  opacity: 1;
  visibility: visible;
  transform: translateX(-50%) translateY(0);
}
.nav__dropdown a {
  display: flex;
  align-items: center;
  gap: 9px;
  padding: 10px 14px;
  font-size: 14px;
  color: var(--text-muted);
  border-radius: 9px;
  white-space: nowrap;
  transition: all var(--transition);
}
.nav__dropdown a::before {
  content: '';
  width: 5px; height: 5px;
  border-radius: 50%;
  background: var(--primary);
  opacity: 0.35;
  transition: all var(--transition);
}
.nav__dropdown a:hover {
  color: var(--primary);
  background: rgba(255, 105, 0, 0.08);
}
.nav__dropdown a:hover::before { opacity: 1; transform: scale(1.35); }

/* 移动端汉堡 */
.menu-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  padding: 8px;
}
.menu-toggle span {
  width: 24px; height: 2px;
  background: var(--text-dark);
  border-radius: 2px;
  transition: all var(--transition);
}
.menu-toggle.open span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
.menu-toggle.open span:nth-child(2) { opacity: 0; }
.menu-toggle.open span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }

/* ============================================================
   Hero 首屏
   ============================================================ */
.hero {
  position: relative;
  background: var(--bg-dark);
  color: var(--text-light);
  padding: 170px 0 0;
  overflow: hidden;
}
.hero__bg { position: absolute; inset: 0; pointer-events: none; }
.hero__glow {
  position: absolute;
  width: 600px; height: 600px;
  border-radius: 50%;
  filter: blur(120px);
  opacity: 0.25;
}
.hero__glow--1 { background: var(--primary); top: -200px; left: -150px; }
.hero__glow--2 { background: var(--accent-2); bottom: -250px; right: -150px; opacity: 0.18; }
.hero__grid {
  position: absolute; inset: 0;
  background-image:
    linear-gradient(rgba(255,255,255,0.04) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255,255,255,0.04) 1px, transparent 1px);
  background-size: 48px 48px;
  mask-image: radial-gradient(ellipse at center, #000 30%, transparent 75%);
  -webkit-mask-image: radial-gradient(ellipse at center, #000 30%, transparent 75%);
}

.hero__inner {
  position: relative;
  display: grid;
  grid-template-columns: 1.1fr 0.9fr;
  gap: 48px;
  align-items: center;
}
.hero__badge {
  display: inline-block;
  padding: 10px 26px;
  background: rgba(255, 105, 0, 0.12);
  border: 1px solid rgba(255, 105, 0, 0.35);
  color: var(--accent);
  border-radius: 999px;
  font-size: 30px;   /* 胶囊标签字号 */
  font-weight: 700;
  line-height: 1.3;
  margin-bottom: 22px;
}
.hero__title {
  font-size: 52px;
  font-weight: 900;
  line-height: 1.15;
  margin-bottom: 18px;
  letter-spacing: -1px;
}
.hero__title-highlight {
  background: linear-gradient(135deg, var(--accent), var(--primary-light));
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
}
.hero__subtitle {
  font-size: 17px;
  color: var(--text-muted-l);
  max-width: 480px;
  margin-bottom: 24px;
}
.hero__features {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-bottom: 32px;
}
.hero__features li {
  padding: 6px 14px;
  background: var(--card-bg-dark);
  border: 1px solid var(--border-dark);
  border-radius: 8px;
  font-size: 13px;
  font-weight: 500;
  color: var(--text-light);
}
.hero__actions { display: flex; gap: 14px; }

/* 按钮 */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 13px 32px;
  border-radius: 10px;
  font-size: 15px;
  font-weight: 600;
  transition: all var(--transition);
}
.btn--primary {
  background: linear-gradient(135deg, var(--primary), var(--accent));
  color: #fff;
  box-shadow: 0 8px 24px rgba(37, 99, 235, 0.4);
}
.btn--primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 12px 32px rgba(255, 105, 0, 0.45);
}
.btn--ghost {
  color: var(--text-light);
  border: 1px solid var(--border-dark);
  background: transparent;
}
.btn--ghost:hover { border-color: var(--accent); color: var(--accent); }
.btn--block { width: 100%; }

/* Hero 右侧：品牌 Logo 展示（带浮动动画） */
.hero__visual {
  position: relative;
  display: flex;
  justify-content: center;
  align-items: center;
}
.hero__logo-card {
  background: transparent;  /* 透明底 */
  padding: 0;
  animation: float 5s ease-in-out infinite;
}
.hero__img {
  max-width: 520px;
  width: 100%;
  height: auto;
  display: block;
}

.hero__chip {
  position: absolute;
  padding: 8px 16px;
  background: rgba(255,255,255,0.1);
  border: 1px solid rgba(255,255,255,0.15);
  backdrop-filter: blur(8px);
  border-radius: 12px;
  font-size: 13px;
  font-weight: 600;
  color: var(--accent);
  animation: float 4s ease-in-out infinite reverse;
}
.hero__chip--1 { top: 20px; right: -10px; }
.hero__chip--2 { bottom: 30px; left: -20px; animation-delay: 1s; }

@keyframes float {
  0%, 100% { transform: translateY(0); }
  50% { transform: translateY(-14px); }
}

/* Hero 统计条 */
.hero__stats {
  position: relative;
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 16px;
  margin-top: 64px;
  padding: 28px 24px;
  background: rgba(255,255,255,0.04);
  border: 1px solid var(--border-dark);
  border-radius: var(--radius);
  backdrop-filter: blur(8px);
  margin-bottom: 0;
}
.stat { text-align: center; }
.stat__num {
  display: block;
  font-size: 30px;
  font-weight: 900;
  background: linear-gradient(135deg, #fff, var(--accent));
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
  font-variant-numeric: tabular-nums;
}
.stat__label { font-size: 13px; color: var(--text-muted-l); }

/* ============================================================
   通用区块
   ============================================================ */
.section { padding: 88px 0; }
.section--dark {
  background: var(--bg-dark);
  color: var(--text-light);
}
.section--gray { background: var(--bg-gray); }
.section--cta { background: linear-gradient(160deg, #f0f7ff, #e8f4ff); }

.section__head { text-align: center; max-width: 720px; margin: 0 auto 52px; }
.section__tag {
  display: inline-block;
  padding: 4px 14px;
  background: rgba(37, 99, 235, 0.1);
  color: var(--primary);
  border-radius: 14px;
  font-size: 13px;
  font-weight: 700;
  margin-bottom: 14px;
}
.section--dark .section__tag {
  background: rgba(255, 105, 0, 0.12);
  color: var(--accent);
}
.section__title {
  font-size: 34px;
  font-weight: 800;
  letter-spacing: -0.5px;
  margin-bottom: 12px;
}
.section__desc { font-size: 15px; color: var(--text-muted); }
.section--dark .section__desc { color: var(--text-muted-l); }

/* ============================================================
   核心优势
   ============================================================ */
.advantages__grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 22px;
}
.adv-card {
  position: relative;   /* 给线条动效定位 */
  background: var(--card-bg);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 30px 26px;
  transition: all var(--transition);
}
/* 悬停时四周“画”出小米橙线条：上边从左往右、下边从右往左、左边从上往下、右边从下往上
   同一套动效同时用于：核心优势卡(.adv-card) / 服务承诺卡(.service-card) / FAQ条目(.faq-item) / 双生态卡(.eco-card) */
.adv-card::before,
.adv-card::after,
.service-card::before,
.service-card::after,
.faq-item::before,
.faq-item::after,
.eco-card::before,
.eco-card::after {
  content: '';
  position: absolute;
  inset: 0;
  border-radius: inherit;
  pointer-events: none;
  transition: background-size .45s cubic-bezier(.22, .61, .36, 1);
}
.adv-card::before,
.service-card::before,
.faq-item::before,
.eco-card::before {
  background:
    linear-gradient(var(--primary), var(--primary)) left top / 0% 3px no-repeat,   /* 上线 */
    linear-gradient(var(--primary), var(--primary)) right bottom / 0% 3px no-repeat; /* 下线 */
}
.adv-card::after,
.service-card::after,
.faq-item::after,
.eco-card::after {
  background:
    linear-gradient(var(--primary), var(--primary)) left top / 3px 0% no-repeat,    /* 左线 */
    linear-gradient(var(--primary), var(--primary)) right bottom / 3px 0% no-repeat; /* 右线 */
  transition-delay: .08s;
}
.adv-card:hover::before, .service-card:hover::before, .faq-item:hover::before, .eco-card:hover::before { background-size: 100% 3px, 100% 3px; }
.adv-card:hover::after,  .service-card:hover::after,  .faq-item:hover::after,  .eco-card:hover::after  { background-size: 3px 100%, 3px 100%; }
.adv-card:hover {
  transform: translateY(-6px);
  box-shadow: var(--shadow-hover);
  border-color: rgba(255, 105, 0, 0.3);
}
.adv-card__icon {
  width: 54px; height: 54px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 26px;
  background: linear-gradient(135deg, #eff6ff, #e0f2fe);
  border-radius: 14px;
  margin-bottom: 18px;
}
.adv-card__title { font-size: 18px; font-weight: 700; margin-bottom: 10px; }
.adv-card__text { font-size: 14px; color: var(--text-muted); }

/* ============================================================
   双生态
   ============================================================ */
.eco__grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 22px;
  margin-bottom: 36px;
}
.eco-card {
  position: relative;   /* 给线条动效定位 */
  padding: 34px 30px;
  border-radius: var(--radius);
  border: 1px solid var(--border-dark);
  background: var(--card-bg-dark);
  transition: all var(--transition);
}
.eco-card:hover {
  transform: translateY(-4px);
  border-color: rgba(255,255,255,0.25);
  background: rgba(255,255,255,0.08);
}
.eco-card--hicar { border-top: 3px solid #ef4444; }
.eco-card--carplay { border-top: 3px solid #94a3b8; }
.eco-card__logo { display: flex; align-items: center; gap: 12px; margin-bottom: 16px; }
.eco-card__icon { width: 40px; height: 40px; object-fit: contain; border-radius: 10px; }
.eco-card__emoji { font-size: 34px; }
.eco-card__name { font-size: 22px; font-weight: 800; color: #fff; }
.eco-card__desc { font-size: 14px; color: var(--text-muted-l); margin-bottom: 18px; }
.eco-card__list { display: flex; flex-wrap: wrap; gap: 8px; }
.eco-card__list li {
  padding: 5px 12px;
  background: rgba(255,255,255,0.07);
  border-radius: 8px;
  font-size: 13px;
  color: var(--text-light);
}

.eco__points {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 14px;
  max-width: 760px;
  margin: 0 auto;
}
.eco__points li {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 14px;
  color: var(--text-light);
}
.eco__points li::before {
  content: '✓';
  flex-shrink: 0;
  width: 22px; height: 22px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: rgba(255, 105, 0, 0.15);
  color: var(--accent);
  border-radius: 50%;
  font-size: 12px;
  font-weight: 700;
}

/* ============================================================
   产品介绍
   ============================================================ */
.product__inner {
  display: grid;
  grid-template-columns: 1fr 1.1fr;
  gap: 64px;
  align-items: center;
}
.product__visual {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 18px;
}
/* 产品图：盒子外包装实拍图（原 .product-box* CSS 绘制块已替换为 <img>） */
.product__img {
  display: block;
  width: 100%;
  max-width: 460px;
  height: auto;
  border-radius: var(--radius);
  filter: drop-shadow(0 20px 40px rgba(255, 105, 0, 0.18));
  transition: transform .4s ease, filter .4s ease;
}
.product__img:hover {
  transform: translateY(-4px) scale(1.02);
  filter: drop-shadow(0 28px 56px rgba(255, 105, 0, 0.28));
}
.product-box__caption { font-size: 13px; color: var(--text-muted); }

.product__text .section__tag { margin-bottom: 14px; }
.product__text .section__title { text-align: left; margin-bottom: 16px; }
.product__desc {
  font-size: 15px;
  color: var(--text-muted);
  margin-bottom: 24px;
}
.product__features { margin-bottom: 30px; }
.product__features li {
  display: flex;
  align-items: flex-start;
  gap: 12px;
  padding: 9px 0;
  font-size: 15px;
  border-bottom: 1px dashed var(--border);
}
.product__features li:last-child { border-bottom: none; }
.check {
  flex-shrink: 0;
  width: 22px; height: 22px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: #dcfce7;
  color: #16a34a;
  border-radius: 50%;
  font-size: 13px;
  font-weight: 700;
  margin-top: 2px;
}

/* ============================================================
   使用步骤
   ============================================================ */
.steps__grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 22px;
  counter-reset: step;
}
.step-card {
  position: relative;
  background: var(--card-bg);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 30px 24px;
  text-align: center;
  transition: all var(--transition);
}
.step-card:hover {
  transform: translateY(-6px);
  box-shadow: var(--shadow-hover);
}
.step-card__num {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 56px; height: 56px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--primary), var(--accent));
  color: #fff;
  font-size: 20px;
  font-weight: 800;
  margin-bottom: 16px;
  box-shadow: 0 8px 20px rgba(37, 99, 235, 0.3);
}
.step-card__title { font-size: 17px; font-weight: 700; margin-bottom: 8px; }
.step-card__text { font-size: 13px; color: var(--text-muted); }
/* 步骤连接箭头（桌面端） */
.step-card:not(:last-child)::after {
  content: '→';
  position: absolute;
  right: -20px;
  top: 50%;
  transform: translateY(-50%);
  color: var(--primary-light);
  font-size: 20px;
  font-weight: 700;
  z-index: 1;
}

/* ============================================================
   使用场景
   ============================================================ */
.scenes__grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 22px;
}
.scene-card {
  background: var(--card-bg);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 30px 24px;
  transition: all var(--transition);
}
.scene-card:hover {
  transform: translateY(-6px);
  box-shadow: var(--shadow-hover);
  border-color: rgba(37, 99, 235, 0.3);
}
.scene-card__icon { font-size: 36px; margin-bottom: 16px; }
.scene-card__title { font-size: 17px; font-weight: 700; margin-bottom: 10px; }
.scene-card__text { font-size: 13.5px; color: var(--text-muted); }

/* ============================================================
   关于我们
   ============================================================ */
.about__grid {
  display: grid;
  grid-template-columns: 1.2fr 1fr;
  gap: 56px;
  align-items: start;
}
.about__name { font-size: 24px; font-weight: 800; color: #fff; margin-bottom: 6px; }
.about__slogan {
  font-size: 14px;
  color: var(--accent);
  font-weight: 600;
  margin-bottom: 20px;
}
.about__desc {
  font-size: 15px;
  color: var(--text-muted-l);
  margin-bottom: 16px;
}
.about__points { display: flex; flex-direction: column; gap: 16px; }
.about-point {
  display: flex;
  flex-direction: column;
  gap: 4px;
  padding: 22px 24px;
  background: var(--card-bg-dark);
  border: 1px solid var(--border-dark);
  border-radius: var(--radius);
  transition: all var(--transition);
}
.about-point:hover { border-color: rgba(255, 105, 0, 0.4); }
.about-point__num {
  font-size: 26px;
  font-weight: 900;
  background: linear-gradient(135deg, #fff, var(--accent));
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
}
.about-point__label { font-size: 13px; color: var(--text-muted-l); }

/* ============================================================
   咨询表单
   ============================================================ */
.contact__grid {
  display: grid;
  grid-template-columns: 1.3fr 1fr;
  gap: 32px;
  align-items: start;
}
.contact-form {
  background: var(--card-bg);
  border-radius: var(--radius);
  padding: 34px 30px;
  box-shadow: var(--shadow);
}
.form-row { display: grid; grid-template-columns: 1fr 1fr; gap: 18px; }
.form-field { margin-bottom: 18px; }
.form-field label {
  display: block;
  font-size: 13px;
  font-weight: 600;
  margin-bottom: 7px;
  color: var(--text-dark);
}
.form-field input,
.form-field textarea {
  width: 100%;
  padding: 12px 14px;
  border: 1.5px solid var(--border);
  border-radius: var(--radius-sm);
  font-size: 14px;
  background: #f8fafc;
  transition: all var(--transition);
  resize: vertical;
}
.form-field input:focus,
.form-field textarea:focus {
  border-color: var(--primary);
  background: #fff;
  box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.12);
}
.form-field input::placeholder,
.form-field textarea::placeholder { color: #a3b1c6; }
.form-tip {
  margin-top: 12px;
  text-align: center;
  font-size: 12px;
  color: var(--text-muted);
}

.contact-info {
  background: var(--bg-dark);
  color: var(--text-light);
  border-radius: var(--radius);
  padding: 34px 30px;
}
.contact-info__title {
  font-size: 19px;
  font-weight: 800;
  color: #fff;
  margin-bottom: 24px;
}
.contact-info__item {
  display: flex;
  align-items: center;
  gap: 14px;
  padding: 14px 0;
  border-bottom: 1px solid var(--border-dark);
}
.contact-info__item:last-child { border-bottom: none; }
.contact-info__icon {
  flex-shrink: 0;
  width: 42px; height: 42px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 19px;
  background: rgba(255, 105, 0, 0.12);
  border-radius: 12px;
}
.contact-info__label {
  display: block;
  font-size: 12px;
  color: var(--text-muted-l);
}
.contact-info__value {
  display: block;
  font-size: 15px;
  font-weight: 600;
  color: #fff;
}

/* ============================================================
   页脚（多列分类布局）
   ============================================================ */
.footer { background: #faf7f2; color: var(--text-muted); padding: 48px 0 30px; }
.footer__top {
  display: grid;
  grid-template-columns: 1.3fr 3fr;
  gap: 44px;
  padding-bottom: 32px;
  border-bottom: 1px solid var(--border);
}
.footer__brand { max-width: 320px; }
.footer__slogan {
  font-size: 13.5px;
  line-height: 1.9;
  margin-top: 14px;
  color: var(--text-muted);
}
.footer__contact {
  font-size: 13px;
  line-height: 2.1;
  margin-top: 14px;
  color: var(--text-muted);
}
.footer__cols {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 26px;
}
.footer__col h4 {
  font-size: 15px;
  font-weight: 700;
  color: var(--text-dark);
  margin-bottom: 14px;
  padding-bottom: 8px;
  position: relative;
}
.footer__col h4::after {
  content: '';
  position: absolute;
  left: 0; bottom: 0;
  width: 22px; height: 3px;
  background: linear-gradient(90deg, var(--primary), var(--accent));
  border-radius: 2px;
}
.footer__col a {
  display: block;
  font-size: 13.5px;
  color: var(--text-muted);
  padding: 5px 0;
  transition: color var(--transition), transform var(--transition);
}
.footer__col a:hover { color: var(--primary); transform: translateX(3px); }
.footer__bottom {
  display: flex;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 10px;
  padding-top: 22px;
  font-size: 12.5px;
}
.footer__icp { color: #64748b; }

/* ============================================================
   回到顶部
   ============================================================ */
.back-top {
  position: fixed;
  right: 28px; bottom: 28px;
  width: 46px; height: 46px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--primary), var(--accent));
  color: #fff;
  font-size: 18px;
  font-weight: 700;
  box-shadow: 0 10px 28px rgba(255, 105, 0, 0.4);
  opacity: 0;
  transform: translateY(16px);
  pointer-events: none;
  transition: all var(--transition);
  z-index: 90;
}
.back-top.show { opacity: 1; transform: translateY(0); pointer-events: auto; }
.back-top:hover { transform: translateY(-3px); }

/* ============================================================
   Toast 提示
   ============================================================ */
.toast {
  position: fixed;
  left: 50%; bottom: 32px;
  transform: translateX(-50%) translateY(70px);
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 13px 26px;
  background: rgba(15, 23, 42, 0.92);
  color: #fff;
  border-radius: 30px;
  font-size: 14px;
  font-weight: 500;
  box-shadow: 0 16px 40px rgba(0,0,0,0.3);
  opacity: 0;
  transition: all 0.35s ease;
  z-index: 9999;
}
.toast.show { opacity: 1; transform: translateX(-50%) translateY(0); }
.toast__dot {
  width: 20px; height: 20px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: #22c55e;
  border-radius: 50%;
  font-size: 12px;
}

/* ============================================================
   子页面通用（使用教程 / 常见问题 / 售后保障 / 关于我们）
   ============================================================ */
.page-hero {
  padding: 150px 0 60px;
  background: linear-gradient(135deg, var(--primary) 0%, var(--accent) 100%);
  color: #fff;
  position: relative;
  overflow: hidden;
}
.page-hero::before {
  content: '';
  position: absolute;
  right: -80px; top: -80px;
  width: 300px; height: 300px;
  border-radius: 50%;
  background: rgba(255,255,255,0.12);
}
.page-hero::after {
  content: '';
  position: absolute;
  left: 18%; bottom: -140px;
  width: 240px; height: 240px;
  border-radius: 50%;
  background: rgba(255,255,255,0.08);
}
.page-hero__title {
  font-size: 38px;
  font-weight: 800;
  letter-spacing: 1px;
  position: relative; z-index: 1;
}
.page-hero__sub {
  font-size: 15px;
  opacity: 0.92;
  margin-top: 10px;
  max-width: 560px;
  position: relative; z-index: 1;
}
.breadcrumb {
  font-size: 13px;
  opacity: 0.85;
  margin-top: 18px;
  display: flex;
  gap: 6px;
  position: relative; z-index: 1;
}
.breadcrumb a { color: #fff; text-decoration: underline; text-underline-offset: 3px; }
.breadcrumb a:hover { opacity: 0.8; }

.page-body { padding: 56px 0 84px; background: var(--bg-gray); }
.page-body .container { max-width: 860px; }
.page-block {
  background: var(--card-bg);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 30px 34px;
  margin-bottom: 26px;
  box-shadow: var(--shadow);
}
.page-block h2 {
  font-size: 20px;
  color: var(--text-dark);
  margin-bottom: 14px;
  display: flex;
  align-items: center;
  gap: 10px;
}
.page-block h2 .pb-icon { font-size: 20px; }
.page-block p {
  font-size: 14.5px;
  color: var(--text-muted);
  margin-bottom: 12px;
  line-height: 2;
}
.page-block p:last-child { margin-bottom: 0; }
.page-block ul, .page-block ol { padding-left: 22px; margin: 12px 0; }
.page-block li {
  font-size: 14.5px;
  color: var(--text-muted);
  margin-bottom: 8px;
  line-height: 1.9;
  list-style: disc;
}
.page-block li b, .page-block p b { color: var(--text-dark); }

/* 使用教程：步骤 */
.tutorial-step {
  display: flex;
  gap: 18px;
  padding: 18px 0;
  border-bottom: 1px dashed var(--border);
}
.tutorial-step:last-child { border-bottom: none; padding-bottom: 0; }
.tutorial-step__num {
  flex-shrink: 0;
  width: 44px; height: 44px;
  border-radius: 12px;
  background: linear-gradient(135deg, var(--primary), var(--accent));
  color: #fff;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 17px;
  font-weight: 800;
  box-shadow: 0 6px 16px rgba(255, 105, 0, 0.3);
}
.tutorial-step__body h3 {
  font-size: 16px;
  color: var(--text-dark);
  margin-bottom: 6px;
}

/* 常见问题：手风琴 */
.faq-item {
  position: relative;   /* 给线条动效定位 */
  background: var(--card-bg);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  margin-bottom: 14px;
  overflow: hidden;
  box-shadow: var(--shadow);
}
.faq-item:hover { border-color: rgba(255, 105, 0, 0.3); }
.faq-item summary {
  cursor: pointer;
  list-style: none;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  padding: 18px 24px;
  font-size: 15px;
  font-weight: 600;
  color: var(--text-dark);
}
.faq-item summary::-webkit-details-marker { display: none; }
.faq-item summary::after {
  content: '+';
  font-size: 22px;
  font-weight: 400;
  color: var(--primary);
  transition: transform 0.3s ease;
  flex-shrink: 0;
}
.faq-item[open] summary::after { transform: rotate(45deg); }
.faq-item[open] summary { border-bottom: 1px solid var(--border); }
.faq-item__a {
  padding: 16px 24px 20px;
  font-size: 14.5px;
  color: var(--text-muted);
  line-height: 2;
}

/* 售后保障：服务卡片 */
.service-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 18px;
  margin-top: 6px;
}
.service-card {
  position: relative;   /* 给线条动效定位 */
  background: var(--card-bg);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 26px 22px;
  text-align: center;
  box-shadow: var(--shadow);
  transition: all var(--transition);
}
.service-card:hover { transform: translateY(-5px); box-shadow: var(--shadow-hover); border-color: rgba(255, 105, 0, 0.3); }
.service-card__icon { font-size: 34px; margin-bottom: 12px; }
.service-card__icon--center {
  display: flex;
  justify-content: center;
  align-items: center;
}
.service-card h3 { font-size: 16px; color: var(--text-dark); margin-bottom: 8px; }
.service-card p { font-size: 13.5px; color: var(--text-muted); line-height: 1.8; }

/* 子页面底部 CTA */
.page-cta {
  background: linear-gradient(135deg, var(--bg-dark), var(--bg-dark-2));
  color: #fff;
  text-align: center;
  padding: 48px 28px;
  border-radius: var(--radius);
}
.page-cta h2 { font-size: 23px; margin-bottom: 10px; }
.page-cta p { color: var(--text-muted-l); margin-bottom: 24px; font-size: 14.5px; }

/* ============================================================
   滚动进入动画
   ============================================================ */
.reveal {
  opacity: 0;
  transform: translateY(28px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}
.reveal.visible { opacity: 1; transform: translateY(0); }

/* ============================================================
   响应式
   ============================================================ */
@media (max-width: 1024px) {
  .hero__inner { grid-template-columns: 1fr; text-align: center; }
  .hero__text { display: flex; flex-direction: column; align-items: center; }
  .hero__subtitle { margin-left: auto; margin-right: auto; }
  .hero__features, .hero__actions { justify-content: center; }
  .hero__visual { margin-top: 16px; }
  .advantages__grid { grid-template-columns: repeat(2, 1fr); }
  .scenes__grid, .steps__grid { grid-template-columns: repeat(2, 1fr); }
  .step-card:not(:last-child)::after { display: none; }
  .product__inner { grid-template-columns: 1fr; gap: 44px; }
  .about__grid { grid-template-columns: 1fr; gap: 36px; }
  .contact__grid { grid-template-columns: 1fr; }
  .hero__title { font-size: 42px; }
  .hero__badge { font-size: 24px; padding: 8px 22px; }
  .footer__top { grid-template-columns: 1fr; gap: 32px; }
  .footer__cols { grid-template-columns: repeat(2, 1fr); gap: 24px; }
}

@media (max-width: 768px) {
  .nav {
    position: fixed;
    top: 92px; left: 0; right: 0;
    flex-direction: column;
    align-items: stretch;
    background: rgba(250, 247, 242, 0.98);  /* 米白色 */
    padding: 14px 20px 20px;
    gap: 6px;
    display: none;
    border-bottom: 1px solid var(--border);
  }
  .nav.open { display: flex; }
  .nav__link--cta { margin-left: 0; text-align: center; }
  .menu-toggle { display: flex; }

  /* 移动端：服务支持下拉直接展开为普通列表 */
  .nav__item { width: 100%; }
  .nav__link--drop { width: 100%; justify-content: space-between; }
  .nav__dropdown {
    position: static;
    transform: none;
    opacity: 1;
    visibility: visible;
    min-width: 0;
    width: auto;
    background: rgba(15, 23, 42, 0.04);
    border: none;
    border-radius: 12px;
    box-shadow: none;
    padding: 6px 8px;
    margin: 2px 0 4px 6px;
  }
  .nav__dropdown::before { display: none; }
  .nav__item:hover .nav__dropdown,
  .nav__item.open .nav__dropdown { transform: none; }
  .nav__dropdown a { white-space: normal; }

  .hero { padding-top: 110px; }
  .hero__title { font-size: 32px; }
  .hero__badge { font-size: 18px; padding: 7px 18px; }
  .hero__stats { grid-template-columns: repeat(2, 1fr); gap: 20px; }
  .eco__grid { grid-template-columns: 1fr; }
  .eco__points { grid-template-columns: 1fr; }
  .section { padding: 60px 0; }
  .section__title { font-size: 26px; }
  .form-row { grid-template-columns: 1fr; }
  .hero__img { max-width: 320px; }
  .hero__chip--1 { right: 0; }
  .hero__chip--2 { left: 0; }
  .page-hero { padding: 120px 0 44px; }
  .page-hero__title { font-size: 30px; }
  .service-grid { grid-template-columns: 1fr; }
}

@media (max-width: 520px) {
  .advantages__grid, .scenes__grid, .steps__grid { grid-template-columns: 1fr; }
  .hero__title { font-size: 27px; }
  .hero__badge { font-size: 15px; padding: 6px 14px; }
  .hero__subtitle { font-size: 15px; }
  .stat__num { font-size: 24px; }
  .footer__bottom { flex-direction: column; text-align: center; }
  .contact-form, .contact-info { padding: 26px 20px; }
  .page-hero { padding: 108px 0 38px; }
  .page-hero__title { font-size: 25px; }
  .page-block { padding: 24px 20px; }
  .tutorial-step { flex-direction: column; gap: 10px; }
}