/* caveplayer.css */
/* ---------- 全局重置 & 基础变量  ---------- */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
  font-family: "Inter", system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
}

body {
  background-color: #000000;
  color: #ffffff;
  line-height: 1.5;
}

/* ---------- 吸顶导航 ---------- */
.sticky-nav {
  position: sticky;
  top: 0;
  z-index: 100;
  background-color: #000000;
  border-bottom: 0px solid rgba(255, 255, 255, 0.051);
  box-shadow: 0 4px 30px rgba(0, 0, 0, 0.9);
}

.nav-container {
  max-width: 1280px;
  margin: 0 auto;
  padding: 0.7rem 1.2rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
}

.logo-area {
  font-size: 1.3rem;
  font-weight: 400;
  letter-spacing: 1px;
  color: #ffffff;
  text-shadow: 0 2px 5px rgba(0, 0, 0, 0.5);
  white-space: nowrap;
  cursor: pointer;
}

.nav-links {
  display: flex;
  gap: 1rem;
  align-items: center;
  flex-wrap: wrap;
  justify-content: flex-end;
}

.nav-links a {
  color: #f0f0f0;
  text-decoration: none;
  font-weight: 500;
  font-size: 1rem;
  padding: 0.3rem 0;
  border-bottom: 2px solid transparent;
  transition: border-color 0.2s, color 0.2s;
  white-space: nowrap;
  text-shadow: 0 1px 4px rgba(0, 0, 0, 0.5);
}
/* 当前活动页面的样式 */
.nav-links a.active {
  border-bottom-color: #3f96ff !important;
  color: #ffffff;
  font-weight: 600;
}
@media (max-width: 420px) {
  .nav-links a {
    font-size: 0.7rem;
  }
  .logo-area {
    font-size: 1.1rem;
  }
}

.nav-links a:hover {
  border-bottom-color: #b0e0ff;
  color: #ffffff;
}

/* ----- 标语区域 (导航正下方，斜体 + 渐变背景卡片) ----- */
.slogan-card {
  max-width: 1280px;
  margin: 1.5rem auto 0.8rem auto;
  padding: 0 1.2rem;
}

.slogan-card-inner {
  background: linear-gradient(145deg, #0e1a2a, #07111f);
  border-radius: 8px;
  padding: 1.6rem 2rem;
  border: 1px solid rgba(255, 255, 255, 0.1);
  box-shadow: 0 25px 40px -20px #000000, 0 0 0 1px rgba(63, 150, 255, 0.2) inset;
  backdrop-filter: blur(4px);
  transition: all 0.3s ease;
}

.slogan-card-inner:hover {
  border-color: rgba(63, 150, 255, 0.5);
  box-shadow: 0 30px 50px -20px #0a2a4a, 0 0 0 1px rgba(63, 150, 255, 0.5) inset;
}

.slogan-text {
  font-size: 1.2rem;
  font-weight: 350;
  font-style: italic;
  letter-spacing: 0.5px;
  color: #ffffff;
  text-shadow: 0 2px 15px rgba(0, 160, 255, 0.5);
  background: linear-gradient(135deg, #f0f9ff, #b8dcff);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  line-height: 1.4;
  word-break: break-word;
}

@media (max-width: 680px) {
  .slogan-text {
    font-size: 1.6rem;
  }
  .slogan-card-inner {
    padding: 1.2rem 1.5rem;
  }
}
@media (max-width: 420px) {
  .slogan-text {
    font-size: 1.3rem;
  }
}

/* ----- 两列视频教学区 ----- */
.video-grid-section {
  max-width: 1280px;
  margin: 2rem auto 2rem auto;
  padding: 0 1.2rem;
}

.two-column-grid {
  display: grid;
  grid-template-columns: 1.25fr 1fr;
  gap: 2rem;
  background: transparent;
}

.video-col {
  background: rgba(10, 15, 25, 0);
  backdrop-filter: blur(8px);
  border: 0px solid rgba(63, 150, 255, 0.2);
  border-radius: 8px;
  padding: 1.6rem 1.8rem;
  box-shadow: 0 20px 30px -15px #000000;
  transition: border-color 0.2s ease, box-shadow 0.2s ease;
}

.col-title {
  font-size: 1.1rem;
  font-weight: 350;
  letter-spacing: 1px;
  margin-bottom: 1.5rem;
  padding-bottom: 0.5rem;
  border-bottom: 2px solid #3f96ff;
  display: inline-block;
  color: #ffffff;
  text-shadow: 0 2px 6px rgba(63, 149, 255, 0);
}

.video-links-list {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 0.55rem;
}

.video-links-list li {
  border-bottom: 1px dashed rgba(255, 255, 255, 0.259);
  padding-bottom: 0.2rem;
}

.video-links-list a {
  color: #f5f8fc;
  text-decoration: none;
  font-size: 1rem;
  display: inline-flex;
  align-items: center;
  gap: 0.6rem;
  transition: color 0.2s, transform 0.2s;
  background: rgba(255,255,255,0.02);
  padding: 0.2rem 0.6rem;
  border-radius: 30px;
  width: 100%;
}

.video-links-list a i {
  color: #3f96ff;
  font-size: 0.85rem;
  width: 1.4rem;
  text-align: center;
}

.video-links-list a:hover {
  color: #ffffff;
  background: rgba(63,150,255,0.1);
  transform: translateX(6px);
  border-radius: 30px;
}

@media (max-width: 700px) {
  .two-column-grid {
    grid-template-columns: 1fr;
    gap: 1.5rem;
  }
  .col-title {
    font-size: 1.4rem;
  }
}

/* ----- 新增卡片：留言支持卡片 (黑色到紫色渐变) ----- */
.support-card-section {
  max-width: 1280px;
  margin: 2rem auto 2rem auto;
  padding: 0 1.2rem;
}

.support-card {
  background: linear-gradient(165deg, #000000 0%, #2e0044 80%, #330256 100%);
  border-radius: 8px;
  padding: 1.8rem 2.2rem;
  border: 1px solid rgba(200, 130, 255, 0.3);
  box-shadow: 0 25px 40px -18px #b200ff55, 0 0 0 1px rgba(180, 100, 255, 0.2) inset;
  backdrop-filter: blur(6px);
  transition: all 0.35s ease;
  cursor: pointer;
  text-decoration: none;
  display: block;
  color: inherit;
}

.support-card:hover {
  border-color: #c77dff;
  box-shadow: none;
  transform: scale(1.01) translateY(-2px);
  background: linear-gradient(145deg, #0d0015 0%, #3a015c 70%, #5e00a3 100%);
}

.support-card p {
  font-size: 1.25rem;
  font-weight: 350;
  line-height: 1.5;
  color: #ffffff;
  text-shadow: 0 2px 15px rgba(180, 90, 255, 0.7);
  letter-spacing: 0.02em;
  word-break: break-word;
  display: flex;
  align-items: center;
  gap: 0.8rem;
}

.support-card i {
  font-size: 2rem;
  color: #d9b0ff;
  filter: drop-shadow(0 0 8px #b266ff);
  transition: transform 0.2s;
}

.support-card:hover i {
  transform: rotate(4deg) scale(1.05);
  color: #f0dcff;
}

@media (max-width: 600px) {
  .support-card p {
    font-size: 1rem;
    flex-wrap: wrap;
  }
  .support-card {
    padding: 1.3rem 1.5rem;
  }
  .support-card i {
    font-size: 1.8rem;
  }
}

/* ----- CavePlayer 功能介绍区域 ----- */
.feature-section {
  max-width: 1280px;
  margin: 2rem auto 2rem auto;
  padding: 0 1.2rem;
}

.feature-card {
  background: rgba(12, 18, 28, 0.75);
  backdrop-filter: blur(8px);
  border: 1px solid rgba(63, 150, 255, 0.2);
  border-radius: 8px;
  padding: 2rem 2rem;
  box-shadow: 0 25px 40px -20px #000000;
  transition: border-color 0.2s ease;
}

.feature-header {
  display: flex;
  align-items: center;
  gap: 0.8rem;
  margin-bottom: 1.8rem;
  border-bottom: 1px solid rgba(255,255,255,0.15);
  padding-bottom: 0.8rem;
}

.feature-header h2 {
  font-size: 1.2rem;
  font-weight: 350;
  letter-spacing: 1px;
  color: #ffffff;
  text-shadow: 0 2px 8px rgba(63,150,255,0.3);
}

.feature-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 1rem 1.8rem;
}

.feature-item {
  border-bottom: 1px dashed rgba(255, 255, 255, 0.15);
  padding: 0.4rem 0 0.4rem 0.2rem;
  transition: background 0.2s;
  border-radius: 8px;
}

.feature-item a {
  color: #f0f4fa;
  text-decoration: none;
  font-size: 1rem;
  display: flex;
  align-items: flex-start;
  gap: 0.75rem;
  line-height: 1.4;
  word-break: break-word;
  white-space: normal;
  padding: 0.25rem 0.25rem 0.25rem 0;
}

.feature-item a i {
  color: #3f96ff;
  font-size: 0.9rem;
  min-width: 1.4rem;
  margin-top: 0.2rem;
  flex-shrink: 0;
}

.feature-item a:hover {
  color: #ffffff;
  border-radius: 30px;
  padding-left: 0.8rem;
  transform: translateX(4px);
  transition: all 0.2s;
}

@media (max-width: 680px) {
  .feature-grid {
    grid-template-columns: 1fr;
    gap: 0.8rem;
  }
  .feature-header h2 {
    font-size: 1.3rem;
  }
  .feature-card {
    padding: 1.5rem 1.2rem;
  }
}

/* ----- 底部扩展信息区 (完全保留自首页，仅微调) ----- */
.footer-extended {
  max-width: 1280px;
  margin: 2rem auto 1rem auto;
  padding: 2rem 1rem 1.5rem;
  background: linear-gradient(145deg, #0b0b0f 0%, #040109 100%);
  border: 1px solid rgba(255, 255, 255, 0.08);
  border-radius: 24px;
  box-shadow: 0 30px 40px -20px #000000;
  backdrop-filter: blur(2px);
  color: #dddddd;
}

.footer-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.8rem 1.2rem;
}

.footer-contact-text {
  display: flex;
  align-items: center;
  gap: 0.7rem;
  font-size: 0.9rem;
  color: #b0b0b0;
  text-decoration: none;
  cursor: default;
}
.footer-contact-text i {
  width: 1.2rem;
  color: #6a8cff;
  font-size: 1rem;
}

@media (max-width: 900px) {
  .footer-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}
@media (max-width: 480px) {
  .footer-grid {
    grid-template-columns: 1fr;
  }
}

.footer-col {
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
}

.footer-col h4 {
  color: #ffffff;
  font-weight: 500;
  font-size: 1.1rem;
  margin-bottom: 0.25rem;
  letter-spacing: 0.3px;
  border-left: 4px solid #3f96ff;
  padding-left: 0.7rem;
}

.footer-contact-item {
  display: flex;
  align-items: center;
  gap: 0.7rem;
  font-size: 0.9rem;
  color: #b0b0b0;
  text-decoration: none;
  transition: color 0.2s;
}
.footer-contact-item i {
  width: 1.2rem;
  color: #6a8cff;
  font-size: 1rem;
}
.footer-contact-item:hover {
  color: #ffffff;
}
.footer-contact-item:hover i {
  color: #97b9ff;
}

.footer-download-links {
  display: flex;
  flex-direction: column;
  gap: 0.6rem;
}
.footer-download-link {
  background: rgba(255, 255, 255, 0.03);
  border: 1px solid rgba(255, 255, 255, 0.1);
  border-radius: 40px;
  padding: 0.45rem 1rem;
  color: #d0d0ff;
  text-decoration: none;
  font-size: 0.9rem;
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  width: fit-content;
  transition: all 0.2s;
}
.footer-download-link i {
  font-size: 0.9rem;
  color: #97b4ff;
}
.footer-download-link:hover {
  background: #3f96ff20;
  border-color: #3f96ff80;
  color: #ffffff;
  transform: translateX(3px);
}

.footer-copyright {
  margin-top: 2rem;
  padding-top: 1.2rem;
  border-top: 1px solid rgba(255, 255, 255, 0.1);
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  align-items: center;
  font-size: 0.8rem;
  color: #888;
}

.footer-copyright a {
  color: #aaa;
  text-decoration: none;
  border-bottom: 1px dotted #444;
}
.footer-copyright a:hover {
  color: #3f96ff;
  border-bottom-color: #3f96ff;
}

.footer-note {
  text-align: center;
  color: rgba(255, 255, 255, 0.4);
  padding: 1.5rem 1rem;
  font-size: 0.8rem;
  z-index: 5;
  background: transparent;
  border-top: 1px solid rgba(255, 255, 255, 0.1);
  margin-top: 1rem;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: center;
  gap: 1rem;
}

.back-to-top-footer {
  display: inline-flex;
  align-items: center;
  gap: 0.3rem;
  color: rgba(255, 255, 255, 0.5);
  text-decoration: none;
  font-size: 0.85rem;
  transition: color 0.2s;
}
.back-to-top-footer:hover {
  color: #3f96ff;
}

/* 右侧悬浮返回顶部链接 */
.back-to-top-side {
  position: fixed;
  bottom: 2.5rem;
  right: 1.2rem;
  z-index: 999;
  background: rgba(20, 20, 25, 0.85);
  backdrop-filter: blur(8px);
  color: #ffffff;
  width: 48px;
  height: 48px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  text-decoration: none;
  box-shadow: 0 8px 20px rgba(0, 0, 0, 0.6);
  border: 1px solid rgba(255, 255, 255, 0.2);
  transition: background 0.2s, transform 0.2s;
  font-size: 1.4rem;
}

.back-to-top-side:hover {
  background: #3f96ff;
  transform: scale(1.08);
  border-color: #3f96ff;
}

.back-to-top-side i {
  color: white;
}

@media (max-width: 600px) {
  .back-to-top-side {
    bottom: 1.5rem;
    right: 1rem;
    width: 42px;
    height: 42px;
    font-size: 1.2rem;
  }
}