/* 咖啡云 (kafeiyun.click) 官方顶级视觉设计系统 v2.2 - 全页咖啡背景版 */

:root {
  --bg-dark: #0d0b0a;
  --bg-card: rgba(30, 24, 20, 0.88);
  --bg-card-hover: rgba(48, 38, 32, 0.95);
  --primary-gold: #ffb703;
  --primary-warm: #e6a15c;
  --text-bright: #ffffff;
  --text-main: #f3eae1;
  --text-readable: #e2d5c7;
  --text-muted: #b8a898;
  --border-color: rgba(230, 161, 92, 0.35);
  --border-glow: rgba(255, 183, 3, 0.7);
  --gradient-gold: linear-gradient(135deg, #ffb703 0%, #e6a15c 100%);
  --gradient-card: linear-gradient(180deg, rgba(38, 30, 25, 0.92) 0%, rgba(18, 14, 12, 0.95) 100%);
  --shadow-glow: 0 10px 30px rgba(230, 161, 92, 0.25);
  --radius-lg: 16px;
  --radius-md: 10px;
  --font-sans: 'Inter', system-ui, -apple-system, 'Segoe UI', Roboto, 'PingFang SC', 'Microsoft YaHei', sans-serif;
}

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

html {
  scroll-behavior: smooth;
  font-family: var(--font-sans);
  background-color: var(--bg-dark);
  color: var(--text-main);
  line-height: 1.6;
}

/* 核心指令修改：背景图咖啡覆盖整个页面 (fixed 全屏平铺) */
body {
  overflow-x: hidden;
  position: relative;
  background: url('../images/coffee_bg.jpg') center/cover no-repeat fixed;
  color: var(--text-main);
  min-height: 100vh;
}

/* 全页渐变遮罩 (保证全页背景沉浸感同时文字高清可读) */
body::before {
  content: "";
  position: fixed;
  inset: 0;
  background: radial-gradient(circle at center, rgba(13, 11, 10, 0.6) 0%, rgba(13, 11, 10, 0.92) 85%);
  z-index: 0;
  pointer-events: none;
}

/* 保证所有子元素在渐变遮罩之上 */
header, main, section, footer, .hero-wrapper {
  position: relative;
  z-index: 1;
}

/* 咖啡冒烟 Canvas (全页层) */
#smoke-canvas {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  z-index: 2;
  pointer-events: none;
  opacity: 0.85;
}

/* 顶部 Hero 容器 */
.hero-wrapper {
  position: relative;
  min-height: 85vh;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  background: transparent;
}

/* Header & Nav */
header {
  position: relative;
  z-index: 10;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 1.25rem 5%;
  background: rgba(13, 11, 10, 0.75);
  backdrop-filter: blur(14px);
  border-bottom: 1px solid var(--border-color);
}

.logo-container {
  display: flex;
  align-items: center;
  gap: 12px;
  text-decoration: none;
}

.logo-img {
  width: 44px;
  height: 44px;
  border-radius: 50%;
  box-shadow: 0 0 15px rgba(230, 161, 92, 0.4);
  border: 1.5px solid var(--primary-gold);
}

.logo-text {
  font-size: 1.5rem;
  font-weight: 800;
  background: var(--gradient-gold);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  letter-spacing: 1px;
}

nav {
  display: flex;
  gap: 2rem;
  align-items: center;
}

nav a {
  color: var(--text-main);
  text-decoration: none;
  font-weight: 500;
  transition: color 0.3s;
}

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

.btn-primary {
  background: var(--gradient-gold);
  color: #0d0b0a;
  padding: 0.75rem 1.75rem;
  border-radius: 50px;
  font-weight: 800;
  text-decoration: none;
  box-shadow: var(--shadow-glow);
  transition: transform 0.3s, box-shadow 0.3s;
  display: inline-flex;
  align-items: center;
  gap: 8px;
  border: none;
  cursor: pointer;
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 12px 35px rgba(255, 183, 3, 0.45);
}

/* Hero Content */
.hero-content {
  position: relative;
  z-index: 5;
  text-align: center;
  max-width: 900px;
  margin: auto;
  padding: 4rem 1.5rem;
}

.hero-tag {
  display: inline-block;
  padding: 0.35rem 1.2rem;
  background: rgba(230, 161, 92, 0.2);
  border: 1px solid var(--border-color);
  border-radius: 30px;
  color: var(--primary-gold);
  font-size: 0.9rem;
  font-weight: 600;
  margin-bottom: 1.5rem;
}

.hero-title {
  font-size: 3.2rem;
  font-weight: 900;
  line-height: 1.25;
  margin-bottom: 1.5rem;
  color: var(--text-bright);
}

.hero-title span {
  background: var(--gradient-gold);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.hero-subtitle {
  font-size: 1.2rem;
  color: var(--text-readable);
  margin-bottom: 2.5rem;
  max-width: 750px;
  margin-left: auto;
  margin-right: auto;
}

.hero-actions {
  display: flex;
  justify-content: center;
  gap: 1.25rem;
  flex-wrap: wrap;
}

.btn-secondary {
  background: rgba(255, 255, 255, 0.08);
  border: 1px solid var(--border-color);
  color: var(--text-bright);
  padding: 0.75rem 1.75rem;
  border-radius: 50px;
  font-weight: 600;
  text-decoration: none;
  transition: all 0.3s;
}

.btn-secondary:hover {
  background: rgba(230, 161, 92, 0.25);
  border-color: var(--primary-gold);
  color: #ffffff;
}

/* Section 通用容器 */
.section {
  padding: 5rem 5%;
  max-width: 1250px;
  margin: 0 auto;
  position: relative;
}

.section-title {
  text-align: center;
  margin-bottom: 3.5rem;
}

.section-title h2 {
  font-size: 2.4rem;
  font-weight: 800;
  margin-bottom: 0.75rem;
  color: var(--text-bright);
}

.section-title p {
  color: var(--text-readable);
  font-size: 1.1rem;
}

/* H2 页面区域：实时下载人数与节点速度（直排上下展示） */
.metrics-section {
  background: var(--gradient-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 3rem 2rem;
  margin-top: -2rem;
  position: relative;
  z-index: 10;
  box-shadow: 0 15px 40px rgba(0, 0, 0, 0.5);
  backdrop-filter: blur(12px);
}

.metrics-vertical-stack {
  display: flex;
  flex-direction: column;
  gap: 2rem;
  max-width: 800px;
  margin: 0 auto;
}

.metric-card-vertical {
  background: rgba(18, 14, 12, 0.85);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 1.75rem 2rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  transition: transform 0.3s, border-color 0.3s;
}

.metric-card-vertical:hover {
  transform: translateY(-3px);
  border-color: var(--primary-gold);
}

.metric-info {
  display: flex;
  align-items: center;
  gap: 1.25rem;
}

.metric-icon {
  width: 52px;
  height: 52px;
  border-radius: 12px;
  background: rgba(230, 161, 92, 0.2);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.6rem;
  color: var(--primary-gold);
}

.metric-details h3 {
  font-size: 1.25rem;
  font-weight: 700;
  margin-bottom: 0.25rem;
  color: var(--text-bright);
}

.metric-details p {
  font-size: 0.92rem;
  color: var(--text-readable);
}

.metric-val {
  font-size: 2.3rem;
  font-weight: 900;
  color: var(--primary-gold);
  font-family: monospace;
}

/* 核心优势: 平排动态展示 */
.features-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 1.5rem;
}

.feature-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 2rem 1.5rem;
  backdrop-filter: blur(12px);
  transition: all 0.4s cubic-bezier(0.165, 0.84, 0.44, 1);
  position: relative;
  overflow: hidden;
  display: flex;
  flex-direction: column;
}

.feature-card::before {
  content: "";
  position: absolute;
  top: 0;
  left: -100%;
  width: 100%;
  height: 3px;
  background: var(--gradient-gold);
  transition: left 0.5s ease;
}

.feature-card:hover {
  background: var(--bg-card-hover);
  border-color: var(--border-glow);
  transform: translateY(-8px);
  box-shadow: 0 15px 35px rgba(230, 161, 92, 0.25);
}

.feature-card:hover::before {
  left: 0;
}

.feature-icon-box {
  width: 52px;
  height: 52px;
  border-radius: 14px;
  background: var(--gradient-gold);
  color: #0d0b0a;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.6rem;
  margin-bottom: 1.25rem;
  font-weight: bold;
  box-shadow: 0 4px 15px rgba(255, 183, 3, 0.3);
  transition: transform 0.3s;
}

.feature-card:hover .feature-icon-box {
  transform: scale(1.1) rotate(5deg);
}

.feature-card h3 {
  font-size: 1.25rem;
  margin-bottom: 0.75rem;
  color: var(--text-bright);
  font-weight: 700;
}

.feature-card p {
  color: var(--text-readable);
  font-size: 0.95rem;
  line-height: 1.65;
}

/* 更多配套选择 */
.pricing-tabs {
  display: flex;
  justify-content: center;
  gap: 1rem;
  margin-bottom: 2.5rem;
  flex-wrap: wrap;
}

.pricing-tab-btn {
  background: rgba(255, 255, 255, 0.08);
  border: 1px solid var(--border-color);
  color: var(--text-readable);
  padding: 0.6rem 1.5rem;
  border-radius: 30px;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.3s;
}

.pricing-tab-btn.active, .pricing-tab-btn:hover {
  background: var(--gradient-gold);
  color: #0d0b0a;
  border-color: var(--primary-gold);
  font-weight: 700;
}

.pricing-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 1.75rem;
  margin-top: 1rem;
}

.pricing-card {
  background: var(--gradient-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 2.25rem 1.75rem;
  position: relative;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  backdrop-filter: blur(12px);
  transition: all 0.3s;
}

.pricing-card:hover {
  border-color: var(--primary-gold);
  transform: translateY(-5px);
  box-shadow: 0 12px 30px rgba(230, 161, 92, 0.25);
}

.pricing-card.featured {
  border: 2px solid var(--primary-gold);
  box-shadow: 0 10px 40px rgba(255, 183, 3, 0.35);
  transform: scale(1.03);
}

.badge-popular {
  position: absolute;
  top: -14px;
  right: 20px;
  background: var(--gradient-gold);
  color: #0d0b0a;
  font-size: 0.8rem;
  font-weight: 800;
  padding: 4px 14px;
  border-radius: 20px;
  text-transform: uppercase;
}

.badge-tag {
  position: absolute;
  top: -14px;
  left: 20px;
  background: rgba(230, 161, 92, 0.3);
  border: 1px solid var(--primary-gold);
  color: var(--primary-gold);
  font-size: 0.75rem;
  font-weight: 700;
  padding: 3px 10px;
  border-radius: 15px;
}

.pricing-header h3 {
  font-size: 1.4rem;
  font-weight: 700;
  margin-bottom: 0.5rem;
  color: var(--text-bright);
}

.pricing-price {
  font-size: 2.6rem;
  font-weight: 900;
  color: var(--primary-gold);
  margin: 0.75rem 0;
}

.pricing-price span {
  font-size: 0.95rem;
  color: var(--text-readable);
  font-weight: 400;
}

.pricing-features {
  list-style: none;
  margin: 1.25rem 0 1.75rem 0;
}

.pricing-features li {
  padding: 0.55rem 0;
  color: var(--text-readable);
  border-bottom: 1px dashed rgba(255, 255, 255, 0.1);
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 0.92rem;
}

.pricing-features li::before {
  content: "✓";
  color: var(--primary-gold);
  font-weight: bold;
}

/* 直排教学区 (教学直排上下展示) */
.tutorial-vertical-stack {
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
  max-width: 850px;
  margin: 0 auto;
}

.tutorial-step-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 2rem;
  display: flex;
  align-items: flex-start;
  gap: 1.5rem;
  backdrop-filter: blur(12px);
  transition: all 0.3s;
}

.tutorial-step-card:hover {
  border-color: var(--primary-gold);
  background: var(--bg-card-hover);
}

.step-num {
  width: 45px;
  height: 45px;
  min-width: 45px;
  border-radius: 50%;
  background: var(--gradient-gold);
  color: #0d0b0a;
  font-weight: 900;
  font-size: 1.3rem;
  display: flex;
  align-items: center;
  justify-content: center;
}

.step-content {
  flex: 1;
}

.step-content h3 {
  font-size: 1.25rem;
  margin-bottom: 0.5rem;
  color: var(--text-bright);
}

.step-content p {
  color: var(--text-readable);
  font-size: 0.95rem;
  margin-bottom: 0.75rem;
}

.step-tags {
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
  align-items: center;
}

.step-tag {
  background: rgba(230, 161, 92, 0.18);
  color: var(--primary-gold);
  border: 1px solid rgba(230, 161, 92, 0.4);
  padding: 2px 10px;
  border-radius: 12px;
  font-size: 0.8rem;
  font-weight: 600;
}

.step-action-link {
  margin-left: auto;
  color: var(--primary-gold);
  text-decoration: none;
  font-weight: 700;
  font-size: 0.9rem;
  display: inline-flex;
  align-items: center;
  gap: 4px;
  transition: transform 0.3s;
}

.step-action-link:hover {
  transform: translateX(4px);
  color: #ffffff;
}

/* 全卡片整体可点击 (a.article-card) */
.articles-preview-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(340px, 1fr));
  gap: 1.75rem;
}

a.article-card {
  text-decoration: none !important;
  color: inherit !important;
  display: flex !important;
  flex-direction: column !important;
  justify-content: space-between !important;
  cursor: pointer !important;
  background: rgba(30, 24, 20, 0.92);
  border: 1px solid rgba(230, 161, 92, 0.35);
  border-radius: var(--radius-lg);
  padding: 1.85rem;
  backdrop-filter: blur(12px);
  transition: transform 0.3s, border-color 0.3s, box-shadow 0.3s;
  box-shadow: 0 6px 20px rgba(0, 0, 0, 0.4);
}

a.article-card:hover {
  transform: translateY(-6px);
  border-color: var(--primary-gold);
  box-shadow: 0 12px 30px rgba(255, 183, 3, 0.3);
  background: rgba(48, 38, 32, 0.98);
}

a.article-card h3 {
  font-size: 1.2rem;
  margin-bottom: 0.85rem;
  line-height: 1.45;
  font-weight: 800;
  color: #ffffff !important;
  transition: color 0.3s;
}

a.article-card:hover h3 {
  color: var(--primary-gold) !important;
}

a.article-card p {
  color: #e2d5c7 !important;
  font-size: 0.94rem;
  line-height: 1.65;
  margin-bottom: 1.25rem;
  font-weight: 400;
}

.article-meta {
  font-size: 0.85rem;
  color: #ffb703 !important;
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-weight: 700;
  border-top: 1px dashed rgba(230, 161, 92, 0.25);
  padding-top: 0.85rem;
}

.read-more-btn {
  color: var(--primary-gold);
  display: inline-flex;
  align-items: center;
  gap: 4px;
  transition: transform 0.3s;
}

a.article-card:hover .read-more-btn {
  transform: translateX(5px);
  color: #ffffff;
}

/* 客户评论直排自动上下展示 */
.reviews-ticker-wrapper {
  max-width: 850px;
  margin: 0 auto;
  height: 380px;
  overflow: hidden;
  position: relative;
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  background: var(--bg-card);
  backdrop-filter: blur(12px);
  padding: 1.5rem 1rem;
}

.reviews-ticker-wrapper::before,
.reviews-ticker-wrapper::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  height: 40px;
  z-index: 5;
  pointer-events: none;
}

.reviews-ticker-wrapper::before {
  top: 0;
  background: linear-gradient(180deg, rgba(13, 11, 10, 0.95) 0%, rgba(13, 11, 10, 0) 100%);
}

.reviews-ticker-wrapper::after {
  bottom: 0;
  background: linear-gradient(0deg, rgba(13, 11, 10, 0.95) 0%, rgba(13, 11, 10, 0) 100%);
}

.reviews-scroll-container {
  display: flex;
  flex-direction: column;
  gap: 1.25rem;
  animation: scrollVertical 22s linear infinite;
}

.reviews-scroll-container:hover {
  animation-play-state: paused;
}

@keyframes scrollVertical {
  0% { transform: translateY(0); }
  100% { transform: translateY(-50%); }
}

.review-item-card {
  background: rgba(18, 14, 12, 0.85);
  border: 1px solid rgba(230, 161, 92, 0.25);
  border-radius: var(--radius-md);
  padding: 1.25rem 1.5rem;
}

.review-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 0.5rem;
}

.review-user {
  display: flex;
  align-items: center;
  gap: 10px;
}

.avatar-circle {
  width: 36px;
  height: 36px;
  border-radius: 50%;
  background: var(--gradient-gold);
  color: #0d0b0a;
  font-weight: bold;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 0.9rem;
}

.user-name {
  font-weight: 700;
  font-size: 0.95rem;
  color: var(--text-bright);
}

.user-role {
  font-size: 0.75rem;
  color: var(--text-readable);
}

.stars {
  color: #ffb703;
  letter-spacing: 2px;
  font-size: 0.9rem;
}

.review-text {
  font-size: 0.92rem;
  color: var(--text-readable);
  line-height: 1.55;
}

/* FAQ 常见问题 */
.faq-container {
  max-width: 850px;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  gap: 1rem;
}

.faq-item {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  overflow: hidden;
  backdrop-filter: blur(12px);
  transition: border-color 0.3s;
}

.faq-item:hover {
  border-color: var(--primary-gold);
}

.faq-question {
  padding: 1.25rem 1.5rem;
  font-weight: 700;
  font-size: 1.05rem;
  cursor: pointer;
  display: flex;
  justify-content: space-between;
  align-items: center;
  user-select: none;
  color: var(--text-bright);
}

.faq-question::after {
  content: "+";
  font-size: 1.4rem;
  color: var(--primary-gold);
  transition: transform 0.3s;
}

.faq-item.active .faq-question::after {
  content: "−";
}

.faq-answer {
  padding: 0 1.5rem 1.25rem 1.5rem;
  color: var(--text-readable);
  font-size: 0.95rem;
  display: none;
  line-height: 1.6;
}

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

/* 页脚 PBN 传输 */
footer {
  background: rgba(7, 6, 5, 0.9);
  border-top: 1px solid var(--border-color);
  padding: 3rem 5% 2rem 5%;
  text-align: center;
  color: var(--text-readable);
  font-size: 0.9rem;
  backdrop-filter: blur(14px);
}

.footer-content {
  max-width: 1000px;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 1.5rem;
}

.footer-links {
  display: flex;
  gap: 1.5rem;
  flex-wrap: wrap;
  justify-content: center;
}

.footer-links a {
  color: var(--text-readable);
  text-decoration: none;
  transition: color 0.3s;
}

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

/* 核心要求：低调美观小字号 PBN 友情链接区 */
.pbn-friend-links {
  margin-top: 1rem;
  padding-top: 1.25rem;
  border-top: 1px dashed rgba(230, 161, 92, 0.2);
  font-size: 0.78rem;
  color: rgba(220, 208, 194, 0.75);
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 1.2rem;
  flex-wrap: wrap;
}

.pbn-friend-links span {
  font-weight: 600;
  color: rgba(255, 183, 3, 0.6);
}

.pbn-friend-links a {
  color: rgba(220, 208, 194, 0.85);
  text-decoration: none;
  transition: color 0.3s;
}

.pbn-friend-links a:hover {
  color: var(--primary-gold);
  text-decoration: underline;
}

/* SEO 文章页专用样式 */
.article-page-container {
  max-width: 900px;
  margin: 3rem auto;
  padding: 0 1.5rem;
}

.article-header {
  margin-bottom: 2.5rem;
  border-bottom: 1px solid var(--border-color);
  padding-bottom: 1.5rem;
}

.article-header h1 {
  font-size: 2.4rem;
  font-weight: 800;
  margin-bottom: 1rem;
  line-height: 1.3;
  background: var(--gradient-gold);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.author-box {
  display: flex;
  align-items: center;
  gap: 1rem;
  margin-top: 1rem;
  background: rgba(230, 161, 92, 0.12);
  padding: 0.75rem 1.25rem;
  border-radius: var(--radius-md);
  border: 1px solid var(--border-color);
}

.author-avatar {
  width: 42px;
  height: 42px;
  border-radius: 50%;
  background: var(--gradient-gold);
  color: #0d0b0a;
  font-weight: bold;
  display: flex;
  align-items: center;
  justify-content: center;
}

.author-info h4 {
  font-size: 0.95rem;
  color: var(--text-bright);
}

.author-info p {
  font-size: 0.8rem;
  color: var(--text-readable);
}

.article-body {
  line-height: 1.85;
  font-size: 1.05rem;
  color: #ece1d6;
}

.article-body h2 {
  font-size: 1.6rem;
  color: var(--primary-gold);
  margin: 2rem 0 1rem 0;
}

.article-body h3 {
  font-size: 1.25rem;
  color: var(--text-bright);
  margin: 1.5rem 0 0.75rem 0;
}

.article-body p {
  margin-bottom: 1.25rem;
}

.article-body ul, .article-body ol {
  margin: 1rem 0 1.5rem 1.5rem;
}

.article-body li {
  margin-bottom: 0.5rem;
}

.internal-link-box {
  background: var(--gradient-card);
  border: 1px solid var(--primary-gold);
  border-radius: var(--radius-md);
  padding: 1.5rem;
  margin: 2.5rem 0;
  text-align: center;
}

.internal-link-box h4 {
  color: var(--primary-gold);
  font-size: 1.2rem;
  margin-bottom: 0.5rem;
}

.internal-link-box a {
  color: var(--text-bright);
  text-decoration: underline;
  font-weight: bold;
}

/* 响应式自适应 */
@media (max-width: 1024px) {
  .features-grid { grid-template-columns: repeat(2, 1fr); }
}

@media (max-width: 768px) {
  .features-grid { grid-template-columns: 1fr; }
  .hero-title { font-size: 2.2rem; }
  .metric-card-vertical { flex-direction: column; text-align: center; gap: 1rem; }
  .tutorial-step-card { flex-direction: column; text-align: center; }
  .step-num { margin: 0 auto; }
  nav { display: none; }
}