/* ==========================================
   btbhy.com.cn — 比特币合约 · 欧易股票交易
   企业级服务专家 视觉系统 v1.0
   Awwwards 级设计语言：数字野兽派 + 渐变流体
   ========================================== */

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

body {
  font-family: system-ui, 'PingFang SC', 'Microsoft YaHei', sans-serif;
  overflow-x: hidden;
  background: #0b0d15;
  color: #e4e6f0;
  line-height: 1.6;
}

/* ----- 核心容器 ----- */
.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 24px;
}

.section {
  padding: 100px 0;
  position: relative;
}

.section:nth-child(even) {
  background: #11141f;
}

/* ----- 导航 — 固定 + 毛玻璃 ----- */
.site-header {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  z-index: 1000;
  background: rgba(11, 13, 21, 0.88);
  backdrop-filter: blur(18px) saturate(180%);
  border-bottom: 1px solid rgba(255, 215, 0, 0.15);
  transition: background 0.3s;
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 72px;
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 24px;
}

.logo {
  display: flex;
  align-items: center;
  gap: 12px;
  font-weight: 800;
  font-size: 1.4rem;
  text-decoration: none;
  color: #f5d742;
  letter-spacing: -0.02em;
}

.logo-icon {
  width: 42px;
  height: 42px;
  border-radius: 12px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.4rem;
  background: linear-gradient(145deg, #f5d742, #d4a017);
  color: #0b0d15;
  box-shadow: 0 0 20px rgba(245, 215, 66, 0.3);
}

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

.main-nav a {
  text-decoration: none;
  font-size: 0.9rem;
  font-weight: 600;
  color: #b0b8d0;
  letter-spacing: 0.5px;
  position: relative;
  transition: color 0.25s;
}

.main-nav a::after {
  content: '';
  position: absolute;
  left: 0;
  bottom: -6px;
  width: 0;
  height: 2px;
  background: #f5d742;
  transition: width 0.3s ease;
}

.main-nav a:hover {
  color: #f5d742;
}

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

.nav-cta {
  padding: 10px 24px;
  border-radius: 40px;
  color: #0b0d15 !important;
  font-weight: 700;
  background: linear-gradient(135deg, #f5d742, #e6b800);
  box-shadow: 0 4px 20px rgba(245, 215, 66, 0.25);
  transition: transform 0.2s, box-shadow 0.2s;
}

.nav-cta:hover {
  transform: scale(1.04);
  box-shadow: 0 6px 30px rgba(245, 215, 66, 0.4);
}

.nav-cta::after {
  display: none !important;
}

.menu-toggle {
  display: none;
  background: none;
  border: none;
  color: #f5d742;
  font-size: 1.6rem;
  cursor: pointer;
}

/* ----- 首页 Hero — 数字野兽派 ----- */
.hero {
  min-height: 85vh;
  display: flex;
  align-items: center;
  position: relative;
  overflow: hidden;
  background: radial-gradient(ellipse 80% 60% at 20% 30%, rgba(245, 215, 66, 0.08), transparent 70%),
              radial-gradient(ellipse 60% 50% at 90% 70%, rgba(230, 184, 0, 0.05), transparent 60%);
}

.hero::before {
  content: '';
  position: absolute;
  top: -30%;
  right: -10%;
  width: 600px;
  height: 600px;
  border-radius: 50%;
  background: radial-gradient(circle, rgba(245, 215, 66, 0.06), transparent 70%);
  pointer-events: none;
}

.hero-content {
  max-width: 760px;
  position: relative;
  z-index: 2;
}

.hero-eyebrow {
  display: inline-block;
  font-size: 0.8rem;
  font-weight: 700;
  padding: 6px 20px;
  border-radius: 40px;
  margin-bottom: 20px;
  background: rgba(245, 215, 66, 0.12);
  color: #f5d742;
  letter-spacing: 2px;
  border: 1px solid rgba(245, 215, 66, 0.2);
  backdrop-filter: blur(4px);
}

.hero h1 {
  font-size: 3.4rem;
  line-height: 1.1;
  margin-bottom: 24px;
  font-weight: 900;
  letter-spacing: -0.03em;
  background: linear-gradient(135deg, #f5d742 0%, #ffec80 50%, #f5d742 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  text-shadow: 0 0 60px rgba(245, 215, 66, 0.15);
}

.hero p {
  font-size: 1.15rem;
  opacity: 0.7;
  max-width: 600px;
  margin-bottom: 36px;
  color: #b0b8d0;
  line-height: 1.7;
}

.hero-buttons {
  display: flex;
  gap: 16px;
}

.hero-image {
  border-radius: 16px;
  overflow: hidden;
  box-shadow: 0 20px 60px rgba(0,0,0,0.5);
  border: 1px solid rgba(245, 215, 66, 0.1);
}

.hero-image img {
  width: 100%;
  height: auto;
  display: block;
}

/* ----- 按钮系统 ----- */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  padding: 14px 32px;
  border-radius: 40px;
  font-weight: 700;
  cursor: pointer;
  border: none;
  text-decoration: none;
  transition: all 0.25s ease;
  font-size: 0.95rem;
  letter-spacing: 0.3px;
}

.btn-primary {
  color: #0b0d15;
  background: linear-gradient(135deg, #f5d742, #e6b800);
  box-shadow: 0 4px 24px rgba(245, 215, 66, 0.3);
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 36px rgba(245, 215, 66, 0.45);
}

.btn-outline {
  background: transparent;
  border: 1.5px solid rgba(245, 215, 66, 0.5);
  color: #f5d742;
}

.btn-outline:hover {
  background: rgba(245, 215, 66, 0.08);
  border-color: #f5d742;
  transform: translateY(-2px);
}

/* ----- 标签 / 标题 ----- */
.section-label {
  display: inline-block;
  font-size: 0.75rem;
  font-weight: 700;
  letter-spacing: 3px;
  margin-bottom: 14px;
  color: #f5d742;
  text-transform: uppercase;
  padding: 4px 0;
  border-bottom: 2px solid rgba(245, 215, 66, 0.3);
}

.section-title {
  font-size: 2.6rem;
  margin-bottom: 16px;
  font-weight: 800;
  letter-spacing: -0.02em;
  color: #f0f2fa;
}

.section-desc {
  max-width: 640px;
  opacity: 0.65;
  margin-bottom: 48px;
  color: #9aa2be;
  font-size: 1.05rem;
}

/* ----- 卡片网格 — 玻璃态 ----- */
.cards-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 28px;
}

.category-card {
  border-radius: 16px;
  padding: 32px;
  background: rgba(255, 255, 255, 0.03);
  border: 1px solid rgba(245, 215, 66, 0.08);
  backdrop-filter: blur(8px);
  transition: all 0.35s cubic-bezier(0.25, 0.46, 0.45, 0.94);
  position: relative;
  overflow: hidden;
}

.category-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: linear-gradient(145deg, rgba(245, 215, 66, 0.04), transparent 60%);
  opacity: 0;
  transition: opacity 0.4s;
}

.category-card:hover {
  transform: translateY(-6px);
  border-color: rgba(245, 215, 66, 0.25);
  box-shadow: 0 12px 40px rgba(0,0,0,0.4), 0 0 30px rgba(245, 215, 66, 0.05);
}

.category-card:hover::before {
  opacity: 1;
}

.card-icon {
  width: 52px;
  height: 52px;
  border-radius: 14px;
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 20px;
  font-size: 1.5rem;
  background: rgba(245, 215, 66, 0.1);
  color: #f5d742;
  border: 1px solid rgba(245, 215, 66, 0.15);
}

.card-link {
  font-weight: 700;
  font-size: 0.85rem;
  text-decoration: none;
  color: #f5d742;
  display: inline-flex;
  align-items: center;
  gap: 6px;
  transition: gap 0.2s;
}

.card-link:hover {
  gap: 12px;
}

/* ----- 特性块 ----- */
.feature-block {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 60px;
  align-items: center;
}

.feature-image {
  border-radius: 16px;
  overflow: hidden;
  border: 1px solid rgba(245, 215, 66, 0.1);
  box-shadow: 0 16px 48px rgba(0,0,0,0.4);
}

.feature-image img {
  width: 100%;
  height: auto;
  display: block;
}

.feature-text {
  position: relative;
}

.feature-list {
  list-style: none;
  margin-top: 8px;
}

.feature-list li {
  padding: 10px 0;
  display: flex;
  align-items: center;
  gap: 12px;
  font-size: 1.05rem;
  color: #c8cee0;
}

.feature-list li::before {
  content: '◆';
  font-weight: 700;
  color: #f5d742;
  font-size: 0.7rem;
}

/* ----- 数据条 ----- */
.stats-bar {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
  text-align: center;
}

.stat-item {
  padding: 32px 20px;
  border-radius: 16px;
  background: rgba(255, 255, 255, 0.02);
  border: 1px solid rgba(245, 215, 66, 0.08);
  transition: border-color 0.3s, transform 0.3s;
}

.stat-item:hover {
  border-color: rgba(245, 215, 66, 0.25);
  transform: translateY(-4px);
}

.stat-number {
  font-size: 2.8rem;
  font-weight: 900;
  background: linear-gradient(135deg, #f5d742, #ffec80);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  line-height: 1.2;
}

.stat-label {
  font-size: 0.9rem;
  opacity: 0.55;
  margin-top: 8px;
  color: #9aa2be;
  letter-spacing: 0.5px;
}

/* ----- 内容墙 — 杂志风网格 ----- */
.content-wall {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
  gap: 28px;
}

.content-wall-item {
  border-radius: 16px;
  overflow: hidden;
  background: rgba(255, 255, 255, 0.02);
  border: 1px solid rgba(245, 215, 66, 0.06);
  transition: all 0.35s ease;
}

.content-wall-item:hover {
  transform: translateY(-5px);
  border-color: rgba(245, 215, 66, 0.2);
  box-shadow: 0 12px 40px rgba(0,0,0,0.35);
}

.content-wall-item img {
  width: 100%;
  height: 220px;
  object-fit: cover;
  display: block;
  transition: transform 0.5s;
}

.content-wall-item:hover img {
  transform: scale(1.03);
}

.content-wall-body {
  padding: 24px;
}

.content-wall-body h3 {
  font-size: 1.2rem;
  margin-bottom: 8px;
  color: #f0f2fa;
}

/* ----- FAQ ----- */
.faq-list {
  max-width: 820px;
  margin: 0 auto;
}

.faq-item {
  border: 1px solid rgba(245, 215, 66, 0.1);
  border-radius: 14px;
  margin-bottom: 10px;
  overflow: hidden;
  cursor: pointer;
  background: rgba(255, 255, 255, 0.02);
  transition: border-color 0.3s;
}

.faq-item:hover {
  border-color: rgba(245, 215, 66, 0.2);
}

.faq-item .faq-question {
  padding: 18px 24px;
  font-weight: 700;
  display: flex;
  justify-content: space-between;
  align-items: center;
  color: #e4e6f0;
  font-size: 1.05rem;
}

.faq-item .faq-question::after {
  content: '+';
  font-size: 1.4rem;
  color: #f5d742;
  transition: transform 0.3s;
}

.faq-item.open .faq-question::after {
  transform: rotate(45deg);
}

.faq-item .faq-answer {
  padding: 0 24px 20px;
  display: none;
  opacity: 0.75;
  color: #b0b8d0;
  line-height: 1.7;
}

.faq-item.open .faq-answer {
  display: block;
  animation: fadeSlide 0.3s ease;
}

@keyframes fadeSlide {
  from { opacity: 0; transform: translateY(-8px); }
  to   { opacity: 0.75; transform: translateY(0); }
}

/* ----- CTA 横幅 — 渐变流体 ----- */
.cta-banner {
  padding: 64px 32px;
  text-align: center;
  border-radius: 20px;
  color: #0b0d15;
  background: linear-gradient(145deg, #f5d742, #e6b800, #f5d742);
  position: relative;
  overflow: hidden;
  box-shadow: 0 16px 60px rgba(245, 215, 66, 0.25);
}

.cta-banner::before {
  content: '';
  position: absolute;
  top: -50%;
  left: -50%;
  width: 200%;
  height: 200%;
  background: radial-gradient(circle at 30% 40%, rgba(255,255,255,0.15), transparent 60%);
  pointer-events: none;
}

.cta-banner h2 {
  color: #0b0d15;
  font-size: 2.2rem;
  font-weight: 900;
  position: relative;
  z-index: 2;
}

.cta-banner .btn-primary {
  background: #0b0d15;
  color: #f5d742;
  box-shadow: 0 4px 24px rgba(0,0,0,0.2);
}

.cta-banner .btn-primary:hover {
  background: #1a1e2e;
  transform: translateY(-2px);
}

/* ----- 页脚 ----- */
.site-footer {
  padding: 64px 0 32px;
  background: #0b0d15;
  border-top: 1px solid rgba(245, 215, 66, 0.06);
}

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

.footer-brand {
  color: #b0b8d0;
  font-size: 0.95rem;
  line-height: 1.7;
}

.footer-col h4 {
  color: #f5d742;
  font-size: 0.9rem;
  margin-bottom: 16px;
  font-weight: 700;
  letter-spacing: 1px;
}

.footer-col a {
  display: block;
  color: #9aa2be;
  text-decoration: none;
  padding: 5px 0;
  font-size: 0.9rem;
  transition: color 0.2s;
}

.footer-col a:hover {
  color: #f5d742;
}

.footer-bottom {
  border-top: 1px solid rgba(245, 215, 66, 0.08);
  margin-top: 48px;
  padding-top: 24px;
  text-align: center;
  font-size: 0.85rem;
  color: #6a7290;
}

/* ----- 工具类 ----- */
.text-accent {
  color: #f5d742;
}

.text-center {
  text-align: center;
}

.seo-description {
  max-width: 640px;
  margin: 0 auto 48px;
  opacity: 0.65;
  color: #9aa2be;
  font-size: 1.05rem;
}

.mt-0 { margin-top: 0; }
.mb-0 { margin-bottom: 0; }

/* ----- 响应式 ----- */
@media (max-width: 1024px) {
  .hero h1 { font-size: 2.8rem; }
  .section-title { font-size: 2.2rem; }
  .footer-grid { grid-template-columns: 1fr 1fr; gap: 32px; }
}

@media (max-width: 768px) {
  .feature-block { grid-template-columns: 1fr; gap: 40px; }
  .stats-bar { grid-template-columns: repeat(2, 1fr); }
  .footer-grid { grid-template-columns: 1fr 1fr; }
  .main-nav { display: none; }
  .menu-toggle { display: flex; }
  .main-nav.open {
    display: flex;
    flex-direction: column;
    position: absolute;
    top: 72px;
    left: 0;
    width: 100%;
    background: rgba(11, 13, 21, 0.98);
    backdrop-filter: blur(20px);
    padding: 28px 24px;
    gap: 20px;
    border-bottom: 1px solid rgba(245, 215, 66, 0.1);
    animation: navSlide 0.25s ease;
  }
  @keyframes navSlide {
    from { opacity: 0; transform: translateY(-8px); }
    to   { opacity: 1; transform: translateY(0); }
  }
  .hero h1 { font-size: 2.4rem; }
  .hero { min-height: 70vh; }
  .section-title { font-size: 1.9rem; }
  .cta-banner h2 { font-size: 1.7rem; }
}

@media (max-width: 480px) {
  .cards-grid,
  .content-wall,
  .stats-bar { grid-template-columns: 1fr; }
  .footer-grid { grid-template-columns: 1fr; }
  .hero-buttons { flex-direction: column; }
  .hero h1 { font-size: 2rem; }
  .section-title { font-size: 1.6rem; }
  .stat-number { font-size: 2.2rem; }
  .container { padding: 0 16px; }
  .section { padding: 64px 0; }
}