/* ============================================
   南京执名知识产权有限公司 - 官方网站
   设计主题：科技 · 低碳 · 绿色 · 电力
   三端响应式适配：1024px / 768px / 480px
   ============================================ */

/* ===== CSS 变量 ===== */
:root {
  /* 科技蓝 */
  --tech: #0d47a1;
  --tech-deep: #071e3d;
  --tech-mid: #1565c0;
  --tech-glow: #42a5f5;
  /* 低碳绿 */
  --green: #00c853;
  --green-deep: #00a844;
  --green-glow: #69f0ae;
  --green-mist: rgba(0,200,83,0.08);
  /* 能源金 */
  --energy: #ffa000;
  --energy-warm: #ff6f00;
  /* 电力靛 */
  --electric: #7c4dff;
  --electric-glow: #b388ff;

  /* 背景系 */
  --bg: #f0f4f8;
  --bg-card: #ffffff;
  --bg-dark: #07121e;
  --bg-dark2: #0c1f35;

  --text: #0d1b2a;
  --text-mid: #4a5568;
  --text-light: #8899aa;
  --border: #e2e8f0;
  --border-glow: rgba(13,71,161,0.15);

  --shadow-sm: 0 2px 8px rgba(0,0,0,0.06);
  --shadow-md: 0 4px 20px rgba(0,0,0,0.10);
  --shadow-lg: 0 12px 40px rgba(0,0,0,0.14);
  --shadow-glow: 0 0 30px rgba(0,200,83,0.15);

  --radius: 12px;
  --radius-sm: 8px;
  --max-w: 1200px;
  --header-h: 70px;
  --trans: 0.3s cubic-bezier(0.25,0.46,0.45,0.94);
}

/* ===== Reset ===== */
*,*::before,*::after { margin:0;padding:0;box-sizing:border-box; }
html { scroll-behavior:smooth;font-size:16px;-webkit-text-size-adjust:100%; }
body {
  font-family: -apple-system,BlinkMacSystemFont,"Segoe UI","PingFang SC","Microsoft YaHei","Noto Sans SC",sans-serif;
  color:var(--text);background:var(--bg);line-height:1.75;overflow-x:hidden;
}
a { text-decoration:none;color:inherit; }
ul { list-style:none; }
img { max-width:100%;display:block; }
.container { max-width:var(--max-w);margin:0 auto;padding:0 24px; }

/* ===== 按钮 ===== */
.btn {
  display:inline-flex;align-items:center;gap:8px;
  padding:12px 30px;border-radius:50px;
  font-size:0.95rem;font-weight:600;cursor:pointer;
  transition:all var(--trans);border:none;
  position:relative;overflow:hidden;
}
.btn-primary {
  background:linear-gradient(135deg,var(--tech),var(--tech-mid));
  color:#fff;box-shadow:0 4px 16px rgba(13,71,161,0.3);
}
.btn-primary:hover { transform:translateY(-2px);box-shadow:0 8px 28px rgba(13,71,161,0.45); }
.btn-accent {
  background:linear-gradient(135deg,var(--green),var(--green-deep));
  color:#fff;box-shadow:0 4px 16px rgba(0,200,83,0.3);
}
.btn-accent:hover { transform:translateY(-2px);box-shadow:0 8px 28px rgba(0,200,83,0.45); }
.btn-outline {
  background:transparent;border:2px solid rgba(255,255,255,0.6);color:#fff;
}
.btn-outline:hover { background:rgba(255,255,255,0.1);border-color:#fff; }
.btn-ghost {
  background:transparent;border:2px solid var(--tech);color:var(--tech);
}
.btn-ghost:hover { background:var(--tech);color:#fff; }

/* ===== 顶部导航 ===== */
.header {
  position:fixed;top:0;left:0;right:0;z-index:1000;
  background:rgba(255,255,255,0.88);backdrop-filter:blur(18px) saturate(140%);
  -webkit-backdrop-filter:blur(18px) saturate(140%);
  border-bottom:1px solid rgba(0,0,0,0.04);
  height:var(--header-h);
}
.header .container { display:flex;align-items:center;justify-content:space-between;height:100%; }
.logo { display:flex;align-items:center;gap:10px;font-weight:800;font-size:1.3rem;color:var(--tech); }
.logo-icon {
  width:40px;height:40px;border-radius:var(--radius-sm);
  background:linear-gradient(135deg,var(--tech),var(--green));
  display:flex;align-items:center;justify-content:center;
  color:#fff;font-size:1.1rem;font-weight:700;
}
.nav { display:flex;gap:2px; }
.nav a {
  padding:8px 16px;border-radius:8px;font-size:0.92rem;font-weight:500;
  color:var(--text-mid);transition:all var(--trans);white-space:nowrap;
}
.nav a:hover,.nav a.active { color:var(--tech);background:rgba(13,71,161,0.06); }
.menu-toggle { display:none;background:none;border:none;font-size:1.5rem;cursor:pointer;color:var(--text);padding:4px 8px; }

/* ===== Hero ===== */
.hero {
  min-height:100vh;display:flex;align-items:center;padding-top:var(--header-h);
  background:radial-gradient(ellipse at 20% 50%, #0a2a4a 0%, #07121e 60%, #041a10 100%);
  color:#fff;position:relative;overflow:hidden;
}
/* 科技网格背景 */
.hero::before {
  content:'';position:absolute;inset:0;
  background-image:
    linear-gradient(rgba(66,165,245,0.06) 1px,transparent 1px),
    linear-gradient(90deg,rgba(66,165,245,0.06) 1px,transparent 1px);
  background-size:60px 60px;
}
/* 光晕 */
.hero::after {
  content:'';position:absolute;top:-50%;right:-20%;
  width:600px;height:600px;border-radius:50%;
  background:radial-gradient(circle,rgba(0,200,83,0.15),transparent 70%);
  pointer-events:none;
}
.hero .container { position:relative;z-index:2; }
.hero-content { max-width:680px; }
.hero h1 { font-size:3.5rem;font-weight:900;line-height:1.15;margin-bottom:22px;letter-spacing:-0.02em; }
.hero h1 span { 
  background:linear-gradient(135deg,var(--green-glow),var(--tech-glow));
  -webkit-background-clip:text;-webkit-text-fill-color:transparent;
}
.hero p { font-size:1.15rem;opacity:0.88;margin-bottom:40px;line-height:1.85;max-width:560px; }
.hero-btns { display:flex;gap:16px;flex-wrap:wrap; }

/* 浮动几何装饰 */
.hero-deco {
  position:absolute;right:8%;top:50%;transform:translateY(-50%);
  display:grid;grid-template-columns:1fr 1fr;gap:24px;
  opacity:0.15;pointer-events:none;
}
.hero-deco .deco-item {
  width:80px;height:80px;border-radius:20px;
}
.hero-deco .deco-item:nth-child(1) { background:var(--tech-glow); }
.hero-deco .deco-item:nth-child(2) { background:var(--green-glow); }
.hero-deco .deco-item:nth-child(3) { background:var(--energy); }
.hero-deco .deco-item:nth-child(4) { background:var(--electric-glow); }

/* ===== Section ===== */
.section { padding:100px 0; }
.section-header { text-align:center;margin-bottom:60px; }
.section-header h2 { font-size:2.4rem;font-weight:800;color:var(--text);margin-bottom:14px; }
.section-header p { font-size:1.05rem;color:var(--text-mid);max-width:640px;margin:0 auto;line-height:1.8; }
.section-tag {
  display:inline-block;padding:5px 18px;border-radius:50px;
  font-size:0.82rem;font-weight:700;margin-bottom:10px;
  background:linear-gradient(135deg,rgba(13,71,161,0.08),rgba(0,200,83,0.08));
  color:var(--tech);border:1px solid rgba(13,71,161,0.12);
}

/* ===== 业务卡片 ===== */
.card-grid {
  display:grid;grid-template-columns:repeat(auto-fit,minmax(270px,1fr));gap:24px;
}
.card {
  background:var(--bg-card);border-radius:var(--radius);padding:40px 28px 32px;
  box-shadow:var(--shadow-sm);border:1px solid var(--border);
  transition:all var(--trans);position:relative;overflow:hidden;
}
.card::before {
  content:'';position:absolute;top:0;left:0;right:0;height:3px;
  transition:all var(--trans);opacity:0;
}
.card:hover {
  transform:translateY(-8px);box-shadow:var(--shadow-lg);
  border-color:transparent;
}
.card:nth-child(1):hover::before { background:linear-gradient(90deg,var(--tech),var(--tech-glow));opacity:1; }
.card:nth-child(2):hover::before { background:linear-gradient(90deg,var(--green),var(--green-glow));opacity:1; }
.card:nth-child(3):hover::before { background:linear-gradient(90deg,var(--energy),#ffc107);opacity:1; }
.card:nth-child(4):hover::before { background:linear-gradient(90deg,var(--electric),var(--electric-glow));opacity:1; }

.card-icon {
  width:52px;height:52px;border-radius:14px;margin-bottom:20px;
  display:flex;align-items:center;justify-content:center;font-size:1.5rem;
}
.card-icon.c-blue { background:rgba(13,71,161,0.12);color:var(--tech); }
.card-icon.c-green { background:rgba(0,200,83,0.12);color:var(--green-deep); }
.card-icon.c-gold { background:rgba(255,160,0,0.12);color:var(--energy-warm); }
.card-icon.c-purple { background:rgba(124,77,255,0.12);color:var(--electric); }

.card h3 { font-size:1.2rem;font-weight:700;margin-bottom:10px; }
.card > p { color:var(--text-mid);font-size:0.93rem;line-height:1.7; }
.card .card-tags {
  display:flex;flex-wrap:wrap;gap:8px;margin-top:16px;padding-top:16px;border-top:1px solid var(--border);
}
.card .card-tags span {
  padding:4px 14px;border-radius:50px;font-size:0.8rem;font-weight:500;
  background:var(--green-mist);color:var(--green-deep);
}

/* ===== 数据亮点 ===== */
.stats {
  display:grid;grid-template-columns:repeat(4,1fr);gap:20px;margin-top:64px;
}
.stat-item {
  text-align:center;padding:32px 16px;background:var(--bg-card);
  border-radius:var(--radius);border:1px solid var(--border);
  transition:all var(--trans);
}
.stat-item:hover { border-color:var(--tech);box-shadow:var(--shadow-glow); }
.stat-item .num {
  font-size:2.6rem;font-weight:900;
  background:linear-gradient(135deg,var(--tech),var(--green));
  -webkit-background-clip:text;-webkit-text-fill-color:transparent;
}
.stat-item .label { color:var(--text-mid);font-size:0.9rem;margin-top:6px; }

/* ===== 为什么选择我们 ===== */
.about-grid { display:grid;grid-template-columns:1fr 1fr;gap:60px;align-items:center; }
.about-text h2 { font-size:2rem;font-weight:800;margin-bottom:22px; }
.about-text p { color:var(--text-mid);margin-bottom:18px;line-height:1.9;font-size:1rem; }
.about-img {
  border-radius:var(--radius);overflow:hidden;box-shadow:var(--shadow-lg);
  aspect-ratio:4/3;display:flex;align-items:center;justify-content:center;font-size:5rem;
  background:linear-gradient(135deg,#e3f2fd,#c8e6c9,#fff9c4);
}
.values { display:grid;grid-template-columns:repeat(4,1fr);gap:18px;margin-top:50px; }
.value-item {
  text-align:center;padding:24px 14px;border-radius:var(--radius);
  border:2px solid var(--border);transition:all var(--trans);background:var(--bg-card);
}
.value-item:hover { border-color:var(--green);box-shadow:var(--shadow-glow); }
.value-item .v-icon { font-size:2rem;margin-bottom:10px; }
.value-item h4 { font-size:0.95rem;font-weight:700;margin-bottom:4px; }
.value-item p { font-size:0.85rem;color:var(--text-mid); }

/* ===== 页内 Hero ===== */
.page-hero {
  padding:150px 0 80px;background:var(--bg-dark);
  color:#fff;text-align:center;position:relative;overflow:hidden;
}
.page-hero::before {
  content:'';position:absolute;inset:0;
  background-image:
    linear-gradient(rgba(66,165,245,0.05) 1px,transparent 1px),
    linear-gradient(90deg,rgba(66,165,245,0.05) 1px,transparent 1px);
  background-size:50px 50px;
}
.page-hero .container { position:relative;z-index:2; }
.page-hero h1 { font-size:2.8rem;font-weight:900;margin-bottom:14px; }
.page-hero h1 span {
  background:linear-gradient(135deg,var(--green-glow),var(--tech-glow));
  -webkit-background-clip:text;-webkit-text-fill-color:transparent;
}
.page-hero p { font-size:1.1rem;opacity:0.82;max-width:620px;margin:0 auto;line-height:1.75; }

/* ===== 子业务详情 ===== */
.sub-service {
  display:grid;grid-template-columns:1fr 1fr;gap:48px;align-items:center;margin-bottom:64px;
}
.sub-service:last-child { margin-bottom:0; }
.sub-service.reverse { direction:rtl; }
.sub-service.reverse > * { direction:ltr; }
.sub-service-img {
  border-radius:var(--radius);overflow:hidden;box-shadow:var(--shadow-lg);
  aspect-ratio:4/3;display:flex;align-items:center;justify-content:center;font-size:4rem;
  background:linear-gradient(135deg,#e8eaf6,#e8f5e9);
}
.sub-service-content h3 { font-size:1.7rem;font-weight:800;margin-bottom:16px;color:var(--text); }
.sub-service-content p { color:var(--text-mid);margin-bottom:18px;line-height:1.85;font-size:1rem; }
.sub-service-content ul { margin-bottom:22px; }
.sub-service-content ul li {
  padding:7px 0;color:var(--text-mid);display:flex;align-items:flex-start;gap:10px;
}
.sub-service-content ul li::before {
  content:'';width:6px;height:6px;border-radius:50%;background:var(--green);
  flex-shrink:0;margin-top:10px;
}

/* ===== 联系信息 ===== */
.contact-grid { display:grid;grid-template-columns:repeat(3,1fr);gap:24px; }
.contact-card {
  text-align:center;padding:36px 20px;background:var(--bg-card);
  border-radius:var(--radius);box-shadow:var(--shadow-sm);border:1px solid var(--border);
  transition:all var(--trans);
}
.contact-card:hover { transform:translateY(-4px);box-shadow:var(--shadow-lg);border-color:var(--tech); }
.contact-card .c-icon { font-size:2.2rem;margin-bottom:14px; }
.contact-card h4 { font-size:1.05rem;font-weight:700;margin-bottom:6px; }
.contact-card p { color:var(--text-mid);font-size:0.95rem; }

/* ===== Footer ===== */
.footer {
  background:var(--bg-dark);color:rgba(255,255,255,0.7);padding:60px 0 30px;
}
.footer-grid { display:grid;grid-template-columns:2fr 1fr 1fr 1fr;gap:40px; }
.footer-brand h3 { color:#fff;font-size:1.3rem;font-weight:800;margin-bottom:12px; }
.footer-brand p { font-size:0.9rem;line-height:1.7; }
.footer-col h4 { color:#fff;font-size:1rem;font-weight:700;margin-bottom:16px; }
.footer-col a { display:block;font-size:0.9rem;padding:5px 0;color:rgba(255,255,255,0.58);transition:color var(--trans); }
.footer-col a:hover { color:var(--green-glow); }
.footer-bottom {
  margin-top:40px;padding-top:20px;border-top:1px solid rgba(255,255,255,0.08);
  text-align:center;font-size:0.85rem;
}
.footer-bottom a { color:var(--green-glow); }

/* ===== 图片占位 ===== */
.img-placeholder { width:100%;height:100%;display:flex;align-items:center;justify-content:center;font-size:5rem;opacity:0.55; }

/* ===== 业务架构图（首页） ===== */
.arch-flow { display:flex;flex-wrap:wrap;justify-content:center;align-items:center;gap:16px;margin-top:48px;padding:28px;background:linear-gradient(135deg,rgba(13,71,161,0.03),rgba(0,200,83,0.03));border-radius:var(--radius); }
.arch-node { padding:14px 22px;border-radius:var(--radius-sm);font-weight:600;font-size:0.9rem;background:var(--bg-card);box-shadow:var(--shadow-sm);border:1px solid var(--border);white-space:nowrap; }
.arch-node.hl { background:linear-gradient(135deg,var(--tech),var(--tech-mid));color:#fff;border:none; }
.arch-arrow { color:var(--green);font-weight:700;font-size:1.2rem; }

/* ===== 亮点横幅 ===== */
.highlight-bar {
  background:linear-gradient(135deg,var(--tech),var(--green-deep));
  color:#fff;padding:24px 0;text-align:center;font-size:1.05rem;font-weight:600;
}

/* ===== 行业背景卡片 ===== */
.insight-card {
  background:var(--bg-card);border-radius:var(--radius);padding:32px;
  border:1px solid var(--border);box-shadow:var(--shadow-sm);
}
.insight-card h3 { font-size:1.1rem;font-weight:700;margin-bottom:10px;color:var(--tech); }
.insight-card p { color:var(--text-mid);font-size:0.95rem;line-height:1.75; }


/* ============================================
   响应式 - 平板 (max-width: 1024px)
   ============================================ */
@media (max-width:1024px) {
  .hero h1 { font-size:2.6rem; }
  .hero-deco { display:none; }
  .sub-service { grid-template-columns:1fr;gap:28px; }
  .sub-service.reverse { direction:ltr; }
  .sub-service-img { max-height:280px; }
  .stats { grid-template-columns:repeat(2,1fr); }
  .about-grid { grid-template-columns:1fr;gap:40px; }
  .about-img { max-height:300px; }
  .values { grid-template-columns:repeat(2,1fr); }
  .footer-grid { grid-template-columns:1fr 1fr; }
  .arch-flow { gap:10px; }
  .arch-node { padding:10px 16px;font-size:0.82rem; }
}

/* ============================================
   响应式 - 手机 (max-width: 768px)
   ============================================ */
@media (max-width:768px) {
  :root { --header-h:60px; }
  .header .container { padding:0 16px; }

  .menu-toggle { display:block; }
  .nav {
    position:fixed;top:var(--header-h);left:0;right:0;
    background:rgba(255,255,255,0.97);backdrop-filter:blur(20px);
    -webkit-backdrop-filter:blur(20px);
    flex-direction:column;padding:12px;box-shadow:var(--shadow-lg);
    display:none;z-index:999;
  }
  .nav.open { display:flex; }
  .nav a { padding:14px 16px;font-size:1rem;border-radius:var(--radius-sm); }

  .hero { text-align:center;min-height:auto;padding:120px 0 80px; }
  .hero h1 { font-size:2rem; }
  .hero p { font-size:0.98rem; }
  .hero-btns { justify-content:center; }

  .section { padding:64px 0; }
  .section-header h2 { font-size:1.7rem; }
  .section-header p { font-size:0.95rem; }

  .card-grid { grid-template-columns:1fr; }
  .stats { grid-template-columns:repeat(2,1fr);gap:12px; }
  .stat-item .num { font-size:1.8rem; }

  .page-hero { padding:110px 0 50px; }
  .page-hero h1 { font-size:1.9rem; }

  .sub-service-content h3 { font-size:1.35rem; }
  .about-text h2 { font-size:1.6rem; }
  .values { grid-template-columns:repeat(2,1fr);gap:10px; }
  .contact-grid { grid-template-columns:1fr; }
  .footer-grid { grid-template-columns:1fr;gap:28px; }
  .arch-flow { flex-direction:column;padding:20px; }
  .arch-arrow { transform:rotate(90deg); }
}

/* ============================================
   响应式 - 小手机 (max-width: 480px)
   ============================================ */
@media (max-width:480px) {
  .hero h1 { font-size:1.7rem; }
  .hero p { font-size:0.9rem; }
  .btn { padding:10px 22px;font-size:0.88rem; }
  .stats { grid-template-columns:1fr 1fr;gap:8px; }
  .stat-item { padding:20px 10px; }
  .stat-item .num { font-size:1.5rem; }
  .page-hero h1 { font-size:1.6rem; }
  .section-header h2 { font-size:1.5rem; }
  .values { grid-template-columns:1fr 1fr; }
  .card { padding:28px 20px; }
}

/* ========= 暗色模式支持（可选） ========= */
@media (prefers-color-scheme:dark) {
  /* 保留亮色主题为主，不做强制 dark mode */
}