/* ============================================================
   5jiejie.com 五个姐姐 · 资源站落地页
   风格：暗黑极简
   ============================================================ */

/* ---------- 基础变量与重置 ---------- */
:root {
  --bg: #0b0d10;
  --bg-soft: #101318;
  --bg-card: #14171d;
  --line: #232830;
  --text: #e8eaed;
  --text-dim: #9aa0a8;
  --accent: #4f8cff;
  --accent-hover: #3b74e6;
  --radius: 14px;
  --max-w: 1080px;
  --shadow: 0 12px 40px rgba(0, 0, 0, 0.45);
}

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

html { scroll-behavior: smooth; }

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC",
    "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.6;
  overflow-x: hidden;
}

a { text-decoration: none; color: inherit; }

/* ---------- 按钮 ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 12px 22px;
  border-radius: 999px;
  font-size: 15px;
  font-weight: 600;
  cursor: pointer;
  transition: transform .2s ease, box-shadow .2s ease, background .2s ease;
  white-space: nowrap;
}

.btn-lg { padding: 15px 30px; font-size: 17px; }

.btn-primary {
  background: linear-gradient(135deg, var(--accent), #7a5bff);
  color: #fff;
  box-shadow: 0 8px 24px rgba(79, 140, 255, 0.35);
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 12px 30px rgba(79, 140, 255, 0.5);
}

.btn-ghost {
  background: transparent;
  color: var(--text);
  border: 1px solid var(--line);
}

.btn-ghost:hover { border-color: var(--accent); color: var(--accent); }

/* ---------- 顶部导航 ---------- */
.nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 50;
  padding: 16px 0;
  transition: background .3s ease, backdrop-filter .3s ease, box-shadow .3s ease;
}

.nav.scrolled {
  background: rgba(11, 13, 16, 0.82);
  backdrop-filter: blur(10px);
  box-shadow: 0 4px 20px rgba(0, 0, 0, 0.3);
}

.nav-inner {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 0 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

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

.brand-mark {
  width: 38px;
  height: 38px;
  border-radius: 10px;
  background: linear-gradient(135deg, var(--accent), #7a5bff);
  color: #fff;
  display: grid;
  place-items: center;
  font-weight: 800;
  font-size: 20px;
}

.brand-text { font-weight: 700; font-size: 18px; letter-spacing: .5px; }
.brand-text em { font-style: normal; color: var(--text-dim); font-size: 13px; margin-left: 6px; }

.nav-cta { padding: 9px 18px; font-size: 14px; }

/* ---------- 首屏 Hero ---------- */
.hero {
  position: relative;
  min-height: 92vh;
  display: flex;
  align-items: center;
  padding: 140px 24px 80px;
  overflow: hidden;
}

.hero-bg {
  position: absolute;
  inset: 0;
  z-index: 0;
  background:
    radial-gradient(ellipse at 70% -10%, rgba(79, 140, 255, 0.18), transparent 50%),
    radial-gradient(ellipse at 20% 110%, rgba(122, 91, 255, 0.12), transparent 50%),
    linear-gradient(180deg, #0d1117, #0b0d10);
}

.hero-inner { position: relative; z-index: 1; max-width: var(--max-w); margin: 0 auto; width: 100%; }

.hero-kicker {
  display: inline-block;
  padding: 6px 16px;
  border: 1px solid var(--line);
  border-radius: 999px;
  color: var(--accent);
  font-size: 14px;
  letter-spacing: 2px;
  margin-bottom: 24px;
}

.hero-title {
  font-size: clamp(36px, 6vw, 64px);
  font-weight: 800;
  line-height: 1.15;
  margin-bottom: 18px;
}

.hero-title span {
  background: linear-gradient(135deg, var(--accent), #7a5bff);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}

.hero-sub { font-size: 18px; color: var(--text-dim); max-width: 560px; margin-bottom: 34px; }

.hero-actions { display: flex; gap: 16px; flex-wrap: wrap; margin-bottom: 40px; }

.hero-points { display: flex; gap: 26px; flex-wrap: wrap; list-style: none; }

.hero-points li { color: var(--text-dim); font-size: 14px; position: relative; padding-left: 18px; }
.hero-points li::before {
  content: "◆";
  position: absolute;
  left: 0;
  color: var(--accent);
  font-size: 10px;
  top: 6px;
}

/* ---------- 首屏图片展示区 ---------- */
.hero-gallery {
  margin-top: 44px;
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 20px;
}

.hero-gallery img {
  width: 100%;
  aspect-ratio: 3 / 4;
  object-fit: cover;
  border-radius: 14px;
  border: 1px solid var(--line);
  background: var(--bg-soft);
  box-shadow: var(--shadow);
  transition: transform .25s ease, border-color .25s ease;
}

.hero-gallery img:hover {
  transform: translateY(-4px);
  border-color: rgba(79, 140, 255, 0.5);
}

/* ---------- 通用区块 ---------- */
.section {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 90px 24px;
}

.section-alt { border-top: 1px solid var(--line); }

.section-head { text-align: center; margin-bottom: 50px; }

.section-title { font-size: 34px; font-weight: 800; margin-bottom: 12px; }
.section-sub { color: var(--text-dim); font-size: 16px; }

/* ---------- 资源卡片 ---------- */
.cards {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 22px;
}

.card {
  background: var(--bg-card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 30px 26px;
  display: flex;
  flex-direction: column;
  transition: transform .25s ease, border-color .25s ease, box-shadow .25s ease;
}

.card:hover {
  transform: translateY(-6px);
  border-color: rgba(79, 140, 255, 0.5);
  box-shadow: var(--shadow);
}

.card-icon { font-size: 34px; margin-bottom: 16px; }

.card-title { font-size: 20px; font-weight: 700; margin-bottom: 10px; }

.card-desc { color: var(--text-dim); font-size: 14px; flex: 1; margin-bottom: 20px; }

.card-link { align-self: flex-start; padding: 9px 16px; font-size: 14px; }

/* ---------- 亮点 ---------- */
.features {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 22px;
}

.feature {
  background: var(--bg-soft);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 28px 24px;
}

.feature-num {
  font-size: 13px;
  color: var(--accent);
  letter-spacing: 2px;
  display: block;
  margin-bottom: 12px;
}

.feature h3 { font-size: 19px; margin-bottom: 8px; }
.feature p { color: var(--text-dim); font-size: 14px; }

/* ---------- FAQ ---------- */
.faq { max-width: 760px; }

.faq-list {
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.faq-item {
  background: var(--bg-card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  overflow: hidden;
  transition: border-color .25s ease, box-shadow .25s ease;
}

.faq-item.open { border-color: rgba(79, 140, 255, 0.5); box-shadow: var(--shadow); }

.faq-q {
  width: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 14px;
  padding: 18px 22px;
  background: transparent;
  border: 0;
  color: var(--text);
  font-size: 16px;
  font-weight: 600;
  text-align: left;
  cursor: pointer;
  font-family: inherit;
}

.faq-q:hover { color: var(--accent); }

.faq-arrow {
  font-size: 20px;
  color: var(--accent);
  transition: transform .3s ease;
}

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

.faq-a {
  max-height: 0;
  overflow: hidden;
  transition: max-height .35s ease;
}

.faq-a p { padding: 0 22px 18px; color: var(--text-dim); font-size: 14px; }

/* ---------- 底部 CTA ---------- */
.cta {
  max-width: var(--max-w);
  margin: 0 auto 30px;
  padding: 20px 24px;
}

.cta-inner {
  background:
    linear-gradient(135deg, rgba(79, 140, 255, 0.15), rgba(122, 91, 255, 0.18)),
    var(--bg-card);
  border: 1px solid var(--line);
  border-radius: 22px;
  padding: 60px 32px;
  text-align: center;
}

.cta-title { font-size: 30px; font-weight: 800; margin-bottom: 12px; }
.cta-sub { color: var(--text-dim); margin-bottom: 28px; }

/* ---------- 页脚 ---------- */
.footer { border-top: 1px solid var(--line); padding: 40px 24px; }

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

.footer p { font-size: 15px; }
.footer-muted { color: var(--text-dim); font-size: 13px; margin-top: 8px; }

/* ---------- 底部固定浮层 ---------- */
.float-cta {
  position: fixed;
  bottom: 24px;
  right: 24px;
  z-index: 60;
  transform: translateY(140%);
  transition: transform .35s ease;
}

.float-cta.show { transform: translateY(0); }

/* ---------- 响应式 ---------- */
@media (max-width: 600px) {
  .hero { min-height: 84vh; }
  .hero-actions .btn { width: 100%; }
  .float-cta { left: 24px; right: 24px; }
  .float-cta .btn { width: 100%; }
}