/* 91PO官方网站 - 全局样式 */
:root {
  --primary: #ff9900;
  --primary-dark: #e68a00;
  --bg-dark: #0d0d0d;
  --bg-card: #1a1a1a;
  --bg-section: #141414;
  --text-primary: #ffffff;
  --text-secondary: #b0b0b0;
  --text-muted: #777777;
  --border: #2a2a2a;
  --accent-purple: #7c5cfc;
  --max-width: 1200px;
  --header-height: 64px;
}

*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  scroll-behavior: smooth;
  font-size: 16px;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  background: var(--bg-dark);
  color: var(--text-primary);
  line-height: 1.7;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

a {
  color: var(--primary);
  text-decoration: none;
  transition: color 0.2s;
}

a:hover {
  color: var(--primary-dark);
}

img {
  max-width: 100%;
  height: auto;
  display: block;
}

/* Header */
.site-header {
  position: sticky;
  top: 0;
  z-index: 1000;
  background: rgba(13, 13, 13, 0.95);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--border);
  height: var(--header-height);
}

.header-inner {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 20px;
  height: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.logo-link {
  display: flex;
  align-items: center;
  gap: 10px;
}

.logo-link img {
  height: 40px;
  width: auto;
}

.logo-text {
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--text-primary);
}

.logo-text span {
  color: var(--primary);
}

.main-nav {
  display: flex;
  gap: 28px;
  list-style: none;
}

.main-nav a {
  color: var(--text-secondary);
  font-size: 0.95rem;
  font-weight: 500;
  padding: 4px 0;
  border-bottom: 2px solid transparent;
}

.main-nav a:hover,
.main-nav a.active {
  color: var(--primary);
  border-bottom-color: var(--primary);
}

.nav-toggle {
  display: none;
  background: none;
  border: none;
  color: var(--text-primary);
  font-size: 1.5rem;
  cursor: pointer;
  padding: 4px;
}

/* Hero */
.hero {
  background: linear-gradient(135deg, #1a0a00 0%, var(--bg-dark) 50%, #0a0a1a 100%);
  padding: 60px 20px 80px;
  text-align: center;
}

.hero-inner {
  max-width: var(--max-width);
  margin: 0 auto;
}

.hero h1 {
  font-size: 2.2rem;
  line-height: 1.3;
  margin-bottom: 16px;
  font-weight: 800;
}

.hero h1 em {
  color: var(--primary);
  font-style: normal;
}

.hero-desc {
  font-size: 1.1rem;
  color: var(--text-secondary);
  max-width: 700px;
  margin: 0 auto 32px;
}

.btn-primary {
  display: inline-block;
  background: var(--primary);
  color: #000;
  font-weight: 700;
  font-size: 1.05rem;
  padding: 14px 40px;
  border-radius: 8px;
  border: none;
  cursor: pointer;
  transition: background 0.2s, transform 0.2s;
}

.btn-primary:hover {
  background: var(--primary-dark);
  color: #000;
  transform: translateY(-2px);
}

.btn-secondary {
  display: inline-block;
  border: 2px solid var(--primary);
  color: var(--primary);
  font-weight: 600;
  padding: 12px 32px;
  border-radius: 8px;
  margin-left: 12px;
  transition: background 0.2s;
}

.btn-secondary:hover {
  background: rgba(255, 153, 0, 0.1);
  color: var(--primary);
}

/* Sections */
.section {
  padding: 60px 20px;
}

.section-alt {
  background: var(--bg-section);
}

.section-inner {
  max-width: var(--max-width);
  margin: 0 auto;
}

.section-title {
  font-size: 1.75rem;
  font-weight: 700;
  margin-bottom: 12px;
  text-align: center;
}

.section-subtitle {
  text-align: center;
  color: var(--text-secondary);
  margin-bottom: 40px;
  font-size: 1rem;
}

/* Feature Grid */
.feature-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.feature-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: 12px;
  overflow: hidden;
  transition: transform 0.2s, border-color 0.2s;
}

.feature-card:hover {
  transform: translateY(-4px);
  border-color: var(--primary);
}

.feature-card img {
  width: 100%;
  aspect-ratio: 9/16;
  object-fit: cover;
  object-position: top;
}

.feature-card-body {
  padding: 16px;
}

.feature-card h3 {
  font-size: 1.05rem;
  margin-bottom: 8px;
  color: var(--primary);
}

.feature-card p {
  font-size: 0.9rem;
  color: var(--text-secondary);
  line-height: 1.6;
}

/* Category Tags */
.tag-grid {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin: 20px 0;
}

.tag {
  background: var(--bg-card);
  border: 1px solid var(--border);
  color: var(--text-secondary);
  padding: 6px 14px;
  border-radius: 20px;
  font-size: 0.85rem;
}

/* Content Article */
.article-content {
  max-width: 860px;
  margin: 0 auto;
}

.article-content h2 {
  font-size: 1.5rem;
  margin: 36px 0 14px;
  color: var(--primary);
  padding-bottom: 8px;
  border-bottom: 1px solid var(--border);
}

.article-content h3 {
  font-size: 1.2rem;
  margin: 24px 0 10px;
  color: var(--text-primary);
}

.article-content p {
  margin-bottom: 16px;
  color: var(--text-secondary);
  text-align: justify;
}

.article-content ul,
.article-content ol {
  margin: 12px 0 16px 24px;
  color: var(--text-secondary);
}

.article-content li {
  margin-bottom: 8px;
}

.article-content a {
  text-decoration: underline;
  text-underline-offset: 3px;
}

/* Showcase */
.showcase-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 40px;
  align-items: center;
  margin-bottom: 48px;
}

.showcase-row.reverse {
  direction: rtl;
}

.showcase-row.reverse > * {
  direction: ltr;
}

.showcase-img {
  border-radius: 12px;
  border: 1px solid var(--border);
  overflow: hidden;
}

.showcase-img img {
  width: 100%;
}

.showcase-text h3 {
  font-size: 1.4rem;
  margin-bottom: 12px;
  color: var(--primary);
}

.showcase-text p {
  color: var(--text-secondary);
  margin-bottom: 12px;
}

/* Download Section */
.download-box {
  background: linear-gradient(135deg, #1a1000, #1a1a1a);
  border: 1px solid var(--primary);
  border-radius: 16px;
  padding: 40px;
  text-align: center;
  margin: 40px 0;
}

.download-box h2 {
  font-size: 1.6rem;
  margin-bottom: 12px;
}

.download-box p {
  color: var(--text-secondary);
  margin-bottom: 24px;
}

.download-steps {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
  margin-top: 32px;
}

.step-item {
  background: var(--bg-card);
  border-radius: 10px;
  padding: 20px 16px;
  border: 1px solid var(--border);
}

.step-num {
  display: inline-block;
  width: 32px;
  height: 32px;
  background: var(--primary);
  color: #000;
  border-radius: 50%;
  font-weight: 700;
  line-height: 32px;
  margin-bottom: 10px;
}

.step-item h4 {
  font-size: 0.95rem;
  margin-bottom: 6px;
}

.step-item p {
  font-size: 0.82rem;
  color: var(--text-muted);
  margin: 0;
}

/* FAQ */
.faq-list {
  max-width: 860px;
  margin: 0 auto;
}

.faq-item {
  border: 1px solid var(--border);
  border-radius: 10px;
  margin-bottom: 12px;
  overflow: hidden;
}

.faq-question {
  background: var(--bg-card);
  padding: 16px 20px;
  font-weight: 600;
  cursor: pointer;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.faq-answer {
  padding: 0 20px;
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.3s, padding 0.3s;
  color: var(--text-secondary);
}

.faq-item.open .faq-answer {
  padding: 16px 20px;
  max-height: 500px;
}

/* Breadcrumb */
.breadcrumb {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 16px 20px 0;
  font-size: 0.85rem;
  color: var(--text-muted);
}

.breadcrumb a {
  color: var(--text-secondary);
}

.breadcrumb span {
  margin: 0 6px;
}

/* Page Header */
.page-header {
  padding: 40px 20px 20px;
  text-align: center;
  border-bottom: 1px solid var(--border);
  margin-bottom: 40px;
}

.page-header h1 {
  font-size: 2rem;
  margin-bottom: 8px;
}

.page-header p {
  color: var(--text-secondary);
}

/* Error Pages */
.error-page {
  flex: 1;
  display: flex;
  align-items: center;
  justify-content: center;
  text-align: center;
  padding: 60px 20px;
}

.error-code {
  font-size: 6rem;
  font-weight: 900;
  color: var(--primary);
  line-height: 1;
}

.error-page h1 {
  font-size: 1.5rem;
  margin: 16px 0 8px;
}

.error-page p {
  color: var(--text-secondary);
  margin-bottom: 24px;
}

/* Footer */
.site-footer {
  background: var(--bg-section);
  border-top: 1px solid var(--border);
  padding: 48px 20px 24px;
  margin-top: auto;
}

.footer-inner {
  max-width: var(--max-width);
  margin: 0 auto;
}

.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: 32px;
  margin-bottom: 32px;
}

.footer-brand img {
  height: 36px;
  margin-bottom: 12px;
}

.footer-brand p {
  color: var(--text-muted);
  font-size: 0.88rem;
  line-height: 1.6;
}

.footer-col h4 {
  font-size: 0.95rem;
  margin-bottom: 14px;
  color: var(--primary);
}

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

.footer-col li {
  margin-bottom: 8px;
}

.footer-col a {
  color: var(--text-secondary);
  font-size: 0.88rem;
}

.footer-col a:hover {
  color: var(--primary);
}

.footer-bottom {
  border-top: 1px solid var(--border);
  padding-top: 20px;
  text-align: center;
  color: var(--text-muted);
  font-size: 0.82rem;
}

/* Mobile Nav */
@media (max-width: 768px) {
  .nav-toggle {
    display: block;
  }

  .main-nav {
    display: none;
    position: absolute;
    top: var(--header-height);
    left: 0;
    right: 0;
    background: var(--bg-dark);
    flex-direction: column;
    padding: 16px 20px;
    border-bottom: 1px solid var(--border);
    gap: 0;
  }

  .main-nav.open {
    display: flex;
  }

  .main-nav li {
    border-bottom: 1px solid var(--border);
  }

  .main-nav a {
    display: block;
    padding: 14px 0;
  }

  .hero h1 {
    font-size: 1.5rem;
  }

  .hero-desc {
    font-size: 0.95rem;
  }

  .btn-secondary {
    margin-left: 0;
    margin-top: 12px;
    display: block;
  }

  .feature-grid {
    grid-template-columns: repeat(2, 1fr);
    gap: 16px;
  }

  .showcase-row {
    grid-template-columns: 1fr;
    gap: 20px;
  }

  .showcase-row.reverse {
    direction: ltr;
  }

  .download-steps {
    grid-template-columns: repeat(2, 1fr);
  }

  .footer-grid {
    grid-template-columns: 1fr 1fr;
    gap: 24px;
  }

  .section {
    padding: 40px 16px;
  }
}

@media (max-width: 480px) {
  .feature-grid {
    grid-template-columns: 1fr;
  }

  .download-steps {
    grid-template-columns: 1fr;
  }

  .footer-grid {
    grid-template-columns: 1fr;
  }
}