/* ============================================
   Qitu (栖途) — Product Landing Page
   人生路上的灵魂笔记
   ============================================ */

:root {
  --bg-deep: #1a1612;
  --bg-surface: #211c16;
  --bg-card: #2a2318;
  --bg-elevated: #332b1f;
  --accent-primary: #c17f34;
  --accent-warm: #d4a25a;
  --accent-light: #e8c9a0;
  --text-primary: #f0e6d8;
  --text-secondary: #b8a890;
  --text-muted: #8a7e70;
  --border-subtle: rgba(193, 127, 52, 0.1);
  --border-default: rgba(193, 127, 52, 0.15);

  --brand-blue: #378ADD;
  --brand-green: #639922;

  --max-width: 960px;
  --nav-height: 64px;
  --radius-sm: 8px;
  --radius-md: 12px;
  --radius-lg: 16px;
  --radius-xl: 24px;

  --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  --font-serif: 'Noto Serif SC', Georgia, 'Times New Roman', serif;

  --ease-out: cubic-bezier(0.16, 1, 0.3, 1);
  --duration: 0.3s;
}

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

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

body {
  font-family: var(--font-sans);
  background-color: var(--bg-deep);
  color: var(--text-primary);
  line-height: 1.7;
  overflow-x: hidden;
}

a { color: var(--accent-primary); text-decoration: none; transition: color var(--duration) var(--ease-out); }
a:hover { color: var(--accent-warm); }

.container { max-width: var(--max-width); margin: 0 auto; padding: 0 24px; }

/* ============================================
   Navigation — 栖途版
   ============================================ */
.navbar {
  position: fixed; top: 0; left: 0; right: 0; height: var(--nav-height); z-index: 1000;
  background: rgba(26, 22, 18, 0.85); backdrop-filter: blur(20px); -webkit-backdrop-filter: blur(20px);
  border-bottom: 1px solid var(--border-subtle); transition: background var(--duration) var(--ease-out);
}

.nav-container {
  max-width: var(--max-width); margin: 0 auto; padding: 0 24px;
  height: 100%; display: flex; align-items: center; justify-content: space-between;
}

.nav-logo {
  display: flex; align-items: center; gap: 10px;
  color: var(--text-primary) !important; font-weight: 500; font-size: 15px;
}

.logo-sub { font-size: 11px; color: var(--accent-primary); font-weight: 500; letter-spacing: 0.15em; }

.nav-brand {
  display: flex; align-items: center; gap: 8px;
}

.nav-parent {
  font-size: 12px; color: var(--text-muted) !important; font-weight: 400;
  white-space: nowrap; letter-spacing: 0.02em;
}

.nav-parent:hover { color: var(--accent-primary) !important; }

.nav-sep {
  font-size: 14px; color: var(--text-muted); opacity: 0.35;
  line-height: 1; user-select: none;
}

.logo-img {
  width: 28px;
  height: 28px;
  object-fit: contain;
  display: block;
  border-radius: 6px;
  background: transparent;
}

.logo-img-large {
  width: 80px;
  height: 80px;
  border-radius: 12px;
}

.nav-links { display: flex; gap: 28px; }

.nav-link {
  color: var(--text-secondary) !important; font-size: 14px; font-weight: 400;
  transition: color var(--duration) var(--ease-out); position: relative;
}

.nav-link::after {
  content: ''; position: absolute; bottom: -4px; left: 0; width: 0; height: 1px;
  background: var(--accent-primary); transition: width var(--duration) var(--ease-out);
}

.nav-link:hover { color: var(--text-primary) !important; }
.nav-link:hover::after { width: 100%; }

.nav-toggle {
  display: none; flex-direction: column; gap: 5px; background: none; border: none; cursor: pointer; padding: 4px;
}

.nav-toggle span {
  width: 20px; height: 1.5px; background: var(--text-secondary); border-radius: 1px;
  transition: all var(--duration) var(--ease-out);
}

.nav-toggle.active span:nth-child(1) { transform: translateY(6.5px) rotate(45deg); }
.nav-toggle.active span:nth-child(2) { opacity: 0; }
.nav-toggle.active span:nth-child(3) { transform: translateY(-6.5px) rotate(-45deg); }

@media (max-width: 768px) {
  .nav-toggle { display: flex; }
  .nav-links {
    position: fixed; top: var(--nav-height); left: 0; right: 0;
    background: rgba(26, 22, 18, 0.98); backdrop-filter: blur(20px);
    flex-direction: column; align-items: center; padding: 24px 0; gap: 20px;
    border-bottom: 1px solid var(--border-subtle);
    transform: translateY(-100%); opacity: 0; pointer-events: none;
    transition: all var(--duration) var(--ease-out);
  }
  .nav-links.active { transform: translateY(0); opacity: 1; pointer-events: auto; }
}

/* ============================================
   Hero — 栖途版
   ============================================ */
.hero {
  position: relative; min-height: 100vh; display: flex; align-items: center;
  padding: calc(var(--nav-height) + 60px) 0 80px; overflow: hidden;
}

.hero-bg { position: absolute; inset: 0; pointer-events: none; }

.hero-glow {
  position: absolute; border-radius: 50%; filter: blur(100px);
}

.hero-glow-1 {
  width: 600px; height: 600px; top: -15%; right: -10%;
  background: radial-gradient(circle, rgba(193, 127, 52, 0.1), transparent 70%);
}

.hero-glow-2 {
  width: 400px; height: 400px; bottom: 20%; left: -10%;
  background: radial-gradient(circle, rgba(212, 162, 90, 0.06), transparent 70%);
}

.hero-glow-3 {
  width: 300px; height: 300px; top: 40%; left: 30%;
  background: radial-gradient(circle, rgba(193, 127, 52, 0.04), transparent 70%);
}

/* 星空粒子 */
.stars {
  position: absolute; inset: 0;
  background-image:
    radial-gradient(1px 1px at 10% 15%, rgba(232, 201, 160, 0.3), transparent),
    radial-gradient(1px 1px at 25% 8%, rgba(232, 201, 160, 0.2), transparent),
    radial-gradient(1.5px 1.5px at 40% 20%, rgba(212, 162, 90, 0.25), transparent),
    radial-gradient(1px 1px at 55% 5%, rgba(232, 201, 160, 0.3), transparent),
    radial-gradient(1px 1px at 70% 18%, rgba(232, 201, 160, 0.15), transparent),
    radial-gradient(1.2px 1.2px at 85% 12%, rgba(212, 162, 90, 0.2), transparent),
    radial-gradient(1px 1px at 15% 30%, rgba(232, 201, 160, 0.2), transparent),
    radial-gradient(0.8px 0.8px at 60% 28%, rgba(232, 201, 160, 0.15), transparent),
    radial-gradient(1px 1px at 90% 35%, rgba(212, 162, 90, 0.2), transparent),
    radial-gradient(1.3px 1.3px at 35% 40%, rgba(232, 201, 160, 0.18), transparent),
    radial-gradient(1px 1px at 5% 45%, rgba(232, 201, 160, 0.15), transparent),
    radial-gradient(0.8px 0.8px at 78% 42%, rgba(232, 201, 160, 0.2), transparent);
}

.hero-content { position: relative; max-width: 580px; }

.hero-tag {
  font-size: 13px; color: var(--accent-primary); font-weight: 500;
  letter-spacing: 0.12em; margin-bottom: 20px;
}

.hero-title {
  font-family: var(--font-serif); font-size: clamp(30px, 5vw, 44px);
  font-weight: 400; line-height: 1.4; letter-spacing: -0.02em; margin-bottom: 24px;
}

.hero-highlight {
  background: linear-gradient(135deg, var(--accent-primary), var(--accent-warm), var(--accent-light));
  -webkit-background-clip: text; -webkit-text-fill-color: transparent; background-clip: text;
}

.hero-desc { font-size: 16px; color: var(--text-secondary); line-height: 1.8; margin-bottom: 36px; }

.hero-actions { display: flex; gap: 16px; flex-wrap: wrap; margin-bottom: 32px; }

.hero-meta { display: flex; align-items: center; gap: 12px; }

.meta-item {
  display: inline-flex; align-items: center; gap: 6px;
  font-size: 13px; color: var(--text-muted);
}

.meta-divider { color: var(--text-muted); opacity: 0.3; }

.btn {
  display: inline-flex; align-items: center; justify-content: center;
  padding: 12px 28px; border-radius: var(--radius-sm); font-size: 14px; font-weight: 500;
  font-family: var(--font-sans); cursor: pointer; transition: all var(--duration) var(--ease-out);
  border: none; text-decoration: none !important;
}

.btn-primary { background: var(--accent-primary); color: #1a1612 !important; }
.btn-primary:hover { background: var(--accent-warm); transform: translateY(-1px); box-shadow: 0 8px 24px rgba(193, 127, 52, 0.25); }

.btn-ghost { background: transparent; color: var(--text-secondary) !important; border: 1px solid var(--border-default); }
.btn-ghost:hover { border-color: var(--accent-primary); color: var(--accent-primary) !important; }

/* ============================================
   Sections
   ============================================ */
.section { padding: 100px 0; }

.section-header { text-align: center; margin-bottom: 60px; }

.section-tag {
  display: inline-block; font-size: 12px; color: var(--accent-primary); font-weight: 500;
  letter-spacing: 0.12em; margin-bottom: 12px; padding: 4px 14px;
  background: rgba(193, 127, 52, 0.08); border-radius: 20px;
}

.section-title {
  font-family: var(--font-serif); font-size: clamp(22px, 3.5vw, 30px);
  font-weight: 400; letter-spacing: -0.01em; margin-bottom: 16px;
}

.section-desc { font-size: 15px; color: var(--text-muted); max-width: 460px; margin: 0 auto; }

/* ============================================
   Features — 核心功能
   ============================================ */
.features { background: var(--bg-surface); }

.feature-grid {
  display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px;
}

.feature-card {
  padding: 28px; background: var(--bg-card); border-radius: var(--radius-lg);
  border: 1px solid var(--border-subtle); transition: all var(--duration) var(--ease-out);
}

.feature-card:hover {
  border-color: var(--border-default); transform: translateY(-3px);
  box-shadow: 0 12px 32px rgba(0, 0, 0, 0.2);
}

.feature-icon { margin-bottom: 18px; }

.feature-name {
  font-family: var(--font-serif); font-size: 18px; font-weight: 400;
  margin-bottom: 10px; letter-spacing: -0.01em;
}

.feature-desc { font-size: 14px; color: var(--text-secondary); line-height: 1.7; }

@media (max-width: 768px) {
  .feature-grid { grid-template-columns: 1fr; max-width: 400px; margin: 0 auto; }
}

@media (min-width: 769px) and (max-width: 1024px) {
  .feature-grid { grid-template-columns: repeat(2, 1fr); }
}

/* ============================================
   Modules — 五大功能模块
   ============================================ */
.module-grid {
  display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px;
}

.module-card {
  padding: 28px; background: var(--bg-card); border-radius: var(--radius-lg);
  border: 1px solid var(--border-subtle); transition: all var(--duration) var(--ease-out);
  display: flex; flex-direction: column;
}

.module-card:hover {
  border-color: var(--border-default); transform: translateY(-3px);
  box-shadow: 0 12px 32px rgba(0, 0, 0, 0.2);
}

.module-emoji { font-size: 28px; display: block; margin-bottom: 14px; }

.module-name {
  font-family: var(--font-serif); font-size: 18px; font-weight: 400;
  margin-bottom: 10px; letter-spacing: -0.01em; color: var(--text-primary);
}

.module-desc {
  font-size: 14px; color: var(--text-secondary); line-height: 1.7;
  flex: 1; margin-bottom: 14px;
}

.module-tags { display: flex; flex-wrap: wrap; gap: 6px; }

.module-tag {
  font-size: 11px; color: var(--accent-primary); font-weight: 500;
  padding: 3px 10px; background: rgba(193, 127, 52, 0.08);
  border-radius: 12px; border: 1px solid rgba(193, 127, 52, 0.1);
}

@media (max-width: 768px) {
  .module-grid { grid-template-columns: 1fr; max-width: 420px; margin: 0 auto; }
}

@media (min-width: 769px) and (max-width: 1024px) {
  .module-grid { grid-template-columns: repeat(2, 1fr); }
}

/* ============================================
   Moods — 心境标签
   ============================================ */
.moods { background: var(--bg-surface); }

.mood-grid {
  display: flex; flex-wrap: wrap; justify-content: center; gap: 16px;
  max-width: 640px; margin: 0 auto;
}

.mood-card {
  display: flex; align-items: center; gap: 10px;
  padding: 14px 22px; background: var(--bg-deep);
  border-radius: var(--radius-xl); border: 1px solid var(--border-subtle);
  transition: all var(--duration) var(--ease-out);
  cursor: default;
}

.mood-card:hover {
  border-color: var(--border-default); transform: translateY(-2px);
  box-shadow: 0 8px 20px rgba(0, 0, 0, 0.15);
}

.mood-emoji { font-size: 20px; line-height: 1; }
.mood-label { font-size: 15px; color: var(--text-secondary); font-weight: 400; }

/* ============================================
   Badges — 荣誉徽章
   ============================================ */
.badges { background: var(--bg-surface); }

.badge-grid {
  display: grid; grid-template-columns: repeat(4, 1fr); gap: 16px;
  max-width: 800px; margin: 0 auto;
}

.badge-card {
  text-align: center; padding: 28px 16px; background: var(--bg-card);
  border-radius: var(--radius-lg); border: 1px solid var(--border-subtle);
  transition: all var(--duration) var(--ease-out);
}

.badge-card:hover {
  border-color: var(--border-default); transform: translateY(-3px);
  box-shadow: 0 8px 24px rgba(0, 0, 0, 0.2);
}

.badge-emoji { display: block; font-size: 32px; margin-bottom: 12px; }

.badge-name {
  display: block; font-family: var(--font-serif); font-size: 16px;
  color: var(--text-primary); margin-bottom: 8px; letter-spacing: -0.01em;
}

.badge-condition { display: block; font-size: 12px; color: var(--text-muted); line-height: 1.5; }

@media (max-width: 768px) {
  .badge-grid { grid-template-columns: repeat(2, 1fr); }
}

@media (max-width: 400px) {
  .badge-grid { grid-template-columns: 1fr; max-width: 280px; }
}

/* ============================================
   Principles — 底线
   ============================================ */
.principles { background: var(--bg-surface); }

.principle-grid {
  display: grid; grid-template-columns: repeat(4, 1fr); gap: 12px;
  max-width: 720px; margin: 0 auto;
}

.principle-card {
  display: flex; align-items: center; gap: 8px;
  padding: 14px 16px; background: var(--bg-card);
  border-radius: var(--radius-md); border: 1px solid var(--border-subtle);
}

.principle-x { color: var(--accent-primary); font-size: 14px; font-weight: 600; opacity: 0.7; flex-shrink: 0; }
.principle-text { font-size: 13px; color: var(--text-muted); }

@media (max-width: 640px) {
  .principle-grid { grid-template-columns: repeat(2, 1fr); }
}

/* ============================================
   CTA — 走入旷野
   ============================================ */
.cta {
  background: var(--bg-surface);
  text-align: center;
  padding: 80px 0;
}

.cta-content {
  max-width: 500px;
  margin: 0 auto;
}

.cta-title {
  font-family: var(--font-serif);
  font-size: clamp(24px, 4vw, 34px);
  font-weight: 400;
  letter-spacing: -0.01em;
  color: var(--accent-light);
  margin-bottom: 32px;
  line-height: 1.5;
}

.btn-cta {
  padding: 16px 40px;
  font-size: 16px;
  font-weight: 500;
}

/* ============================================
   Download — 下载
   ============================================ */
.download-card {
  text-align: center; padding: 60px 40px; background: var(--bg-surface);
  border-radius: var(--radius-xl); border: 1px solid var(--border-subtle);
  position: relative; overflow: hidden;
}

.download-card::before {
  content: ''; position: absolute; top: -50%; left: -50%; width: 200%; height: 200%;
  background: radial-gradient(circle at center, rgba(193, 127, 52, 0.04), transparent 50%);
  pointer-events: none;
}

.download-icon { margin-bottom: 24px; }

.download-title {
  font-family: var(--font-serif); font-size: clamp(22px, 3vw, 28px);
  font-weight: 400; margin-bottom: 12px; position: relative;
}

.download-desc {
  font-size: 15px; color: var(--text-muted); margin-bottom: 32px; position: relative;
}

.download-buttons {
  display: flex; gap: 16px; justify-content: center; flex-wrap: wrap; position: relative;
}

.btn-download {
  padding: 14px 32px; font-size: 15px; gap: 10px;
}

@media (max-width: 480px) {
  .download-card { padding: 40px 24px; }
  .download-buttons { flex-direction: column; align-items: center; }
}

/* ============================================
   Footer — 栖途版
   ============================================ */
.footer { padding: 40px 0; border-top: 1px solid var(--border-subtle); }

.footer-content {
  display: flex; justify-content: space-between; align-items: center; margin-bottom: 24px;
}

.footer-logo { font-family: var(--font-serif); font-size: 16px; color: var(--text-primary); }
.footer-sub { font-size: 11px; color: var(--accent-primary); font-weight: 500; letter-spacing: 0.15em; }
.footer-brand p { font-size: 13px; color: var(--text-muted); margin-top: 4px; }
.footer-links { display: flex; gap: 24px; }
.footer-links a { font-size: 13px; color: var(--text-muted) !important; }
.footer-links a:hover { color: var(--accent-primary) !important; }
.footer-bottom p { font-size: 12px; color: var(--text-muted); text-align: center; }

@media (max-width: 768px) {
  .footer-content { flex-direction: column; gap: 20px; text-align: center; }
}

/* ============================================
   Animations
   ============================================ */
.fade-in {
  opacity: 0; transform: translateY(20px);
  transition: opacity 0.6s var(--ease-out), transform 0.6s var(--ease-out);
}

.fade-in.visible { opacity: 1; transform: translateY(0); }