:root {
  --primary-color: #5d5fef;
  --secondary-color: #a5a6f6;
  --text-color: #1e293b;
  --text-muted: #64748b;
  --bg-color: #ffffff;
  --bg-card: #ffffff;
  --bg-soft: #f8fafc;
  --border: #e2e8f0;
  --border-light: #f1f5f9;
  --gradient-title: linear-gradient(90deg, #60a5fa, #c084fc);
  --gradient-btn: linear-gradient(135deg, #5d5fef, #a5a6f6);
  --gradient-glow: radial-gradient(circle, rgba(93, 95, 239, 0.3) 0%, rgba(192, 132, 252, 0.2) 40%, transparent 70%);
  --radius: 16px;
  --shadow: 0 10px 30px rgba(0, 0, 0, 0.05);
  --shadow-glow: 0 20px 40px rgba(93, 95, 239, 0.15);
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  min-height: 100vh;
  background-color: var(--bg-color);
  background-image: radial-gradient(circle at top right, rgba(93, 95, 239, 0.08), transparent 45%);
  color: var(--text-color);
  font-family: "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Segoe UI", system-ui, sans-serif;
  line-height: 1.75;
}

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

a:hover {
  color: #4346d3;
}

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

.container {
  width: min(1140px, calc(100% - 32px));
  margin: 0 auto;
}

/* Header */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  background: rgba(255, 255, 255, 0.98);
  border-bottom: 1px solid rgba(0, 0, 0, 0.08);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  padding: 16px 0;
}

.brand {
  display: flex;
  align-items: center;
  gap: 10px;
  color: var(--primary-color);
  font-size: 17px;
  font-weight: 800;
  text-decoration: none;
  letter-spacing: -0.02em;
}

.brand:hover {
  color: var(--primary-color);
  opacity: 0.85;
}

.brand-icon {
  width: 32px;
  height: 32px;
  border-radius: 8px;
  object-fit: contain;
  flex-shrink: 0;
  display: block;
}

.site-nav {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  justify-content: flex-end;
}

.site-nav a {
  padding: 8px 16px;
  border-radius: 999px;
  color: var(--text-color);
  font-size: 14px;
  font-weight: 600;
  border: 1px solid transparent;
  text-decoration: none;
}

.site-nav a:hover,
.site-nav a.active {
  color: var(--primary-color);
  background: rgba(93, 95, 239, 0.08);
  border-color: rgba(93, 95, 239, 0.15);
}

/* Hero */
.hero {
  position: relative;
  padding: 72px 0 56px;
  text-align: center;
  overflow: hidden;
}

.hero::before {
  content: "";
  position: absolute;
  inset: 0;
  background: radial-gradient(circle at top right, rgba(93, 95, 239, 0.1), transparent 42%);
  pointer-events: none;
}

.hero::after {
  content: "";
  position: absolute;
  top: 10%;
  left: 50%;
  width: 480px;
  height: 480px;
  transform: translateX(-50%);
  background: var(--gradient-glow);
  filter: blur(60px);
  opacity: 0.55;
  pointer-events: none;
}

.hero .container {
  position: relative;
  z-index: 1;
}

.hero-badge {
  display: inline-block;
  padding: 6px 16px;
  margin-bottom: 20px;
  border-radius: 999px;
  background: rgba(93, 95, 239, 0.08);
  border: 1px solid rgba(93, 95, 239, 0.2);
  color: var(--primary-color);
  font-size: 13px;
  letter-spacing: 0.04em;
}

.hero h1 {
  margin: 0 0 20px;
  font-size: clamp(2rem, 5vw, 3.2rem);
  font-weight: 800;
  line-height: 1.2;
  background: var(--gradient-title);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero .lead {
  max-width: 680px;
  margin: 0 auto 32px;
  color: var(--text-muted);
  font-size: 1.1rem;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  justify-content: center;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 14px 28px;
  border-radius: 12px;
  font-size: 15px;
  font-weight: 600;
  text-decoration: none;
  transition: transform 0.2s, box-shadow 0.2s, background 0.2s;
  cursor: pointer;
  border: none;
}

.btn-primary {
  background: var(--primary-color);
  color: #fff;
  box-shadow: 0 4px 16px rgba(93, 95, 239, 0.35);
}

.btn-primary:hover {
  color: #fff;
  background: #4346d3;
  transform: translateY(-2px);
  box-shadow: var(--shadow-glow);
}

.btn-outline {
  background: #f0f0f0;
  color: var(--text-color);
  border: 1px solid var(--border);
}

.btn-outline:hover {
  background: #e5e5e5;
  color: var(--text-color);
}

/* Features */
.section {
  padding: 56px 0;
}

.section-title {
  text-align: center;
  margin-bottom: 40px;
}

.section-title h2 {
  margin: 0 0 12px;
  font-size: 1.75rem;
  font-weight: 700;
  color: var(--text-color);
}

.section-title p {
  margin: 0;
  color: var(--text-muted);
}

.feature-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 24px;
}

.feature-card {
  padding: 28px;
  border-radius: var(--radius);
  background: var(--bg-card);
  border: 1px solid var(--border);
  box-shadow: var(--shadow);
  transition: border-color 0.2s, transform 0.2s, box-shadow 0.2s;
}

.feature-card:hover {
  border-color: rgba(93, 95, 239, 0.35);
  box-shadow: 0 20px 40px rgba(93, 95, 239, 0.1);
  transform: translateY(-4px);
}

.feature-icon {
  width: 48px;
  height: 48px;
  margin-bottom: 16px;
  border-radius: 12px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 22px;
  background: rgba(93, 95, 239, 0.08);
}

.feature-card h3 {
  margin: 0 0 10px;
  font-size: 1.15rem;
  color: var(--text-color);
}

.feature-card p {
  margin: 0;
  color: var(--text-muted);
  font-size: 0.95rem;
}

/* Download cards */
.download-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 20px;
}

.download-card {
  padding: 24px;
  border-radius: var(--radius);
  background: var(--bg-card);
  border: 1px solid var(--border);
  box-shadow: var(--shadow);
  text-align: center;
}

.download-card h3 {
  margin: 0 0 8px;
  font-size: 1.1rem;
  color: var(--text-color);
}

.download-card p {
  margin: 0 0 16px;
  color: var(--text-muted);
  font-size: 0.9rem;
}

.download-card .btn {
  width: 100%;
}

/* Content blocks */
.content-block {
  padding: 32px;
  margin-bottom: 24px;
  border-radius: var(--radius);
  background: var(--bg-card);
  border: 1px solid var(--border);
  box-shadow: var(--shadow);
}

.content-block h2 {
  margin: 0 0 16px;
  font-size: 1.4rem;
  color: var(--text-color);
}

.content-block h3 {
  margin: 24px 0 10px;
  font-size: 1.1rem;
  color: var(--text-color);
}

.content-block p,
.content-block li {
  color: var(--text-muted);
}

.content-block ul,
.content-block ol {
  padding-left: 1.4em;
}

/* Articles */
.article-list {
  display: grid;
  gap: 20px;
}

.article-item {
  display: block;
  padding: 24px;
  border-radius: var(--radius);
  background: var(--bg-card);
  border: 1px solid var(--border);
  box-shadow: var(--shadow);
  text-decoration: none;
  transition: border-color 0.2s, box-shadow 0.2s;
}

.article-item:hover {
  border-color: rgba(93, 95, 239, 0.35);
  box-shadow: 0 12px 32px rgba(93, 95, 239, 0.1);
}

.article-item h3 {
  margin: 0 0 8px;
  color: var(--text-color);
  font-size: 1.15rem;
}

.article-item p {
  margin: 0 0 10px;
  color: var(--text-muted);
  font-size: 0.95rem;
}

.article-meta {
  color: var(--text-muted);
  font-size: 0.85rem;
}

.article-body h2 {
  margin: 32px 0 12px;
  font-size: 1.3rem;
  color: var(--text-color);
}

.article-body h3 {
  margin: 24px 0 10px;
  font-size: 1.05rem;
  color: var(--text-color);
}

.article-body p,
.article-body li {
  color: var(--text-muted);
}

.daily-tip {
  padding: 20px 24px;
  margin-bottom: 28px;
  border-radius: var(--radius);
  background: linear-gradient(135deg, rgba(93, 95, 239, 0.08), rgba(192, 132, 252, 0.1));
  border: 1px solid rgba(93, 95, 239, 0.2);
}

.daily-tip h3 {
  margin: 0 0 8px;
  font-size: 1rem;
  color: var(--primary-color);
}

.daily-tip p {
  margin: 0;
  color: var(--text-muted);
  font-size: 0.95rem;
}

/* FAQ */
.faq-item {
  padding: 20px 0;
  border-bottom: 1px solid var(--border-light);
}

.faq-item:last-child {
  border-bottom: none;
}

.faq-item h3 {
  margin: 0 0 8px;
  font-size: 1.05rem;
  color: var(--text-color);
}

.faq-item p {
  margin: 0;
  color: var(--text-muted);
}

/* Footer */
.site-footer {
  margin-top: 64px;
  padding: 32px 0;
  border-top: 1px solid var(--border-light);
  background: var(--bg-soft);
  text-align: center;
}

.site-footer p {
  margin: 0 0 8px;
  color: var(--text-muted);
  font-size: 0.9rem;
}

.footer-links {
  display: flex;
  flex-wrap: wrap;
  gap: 16px;
  justify-content: center;
  margin-bottom: 16px;
}

.footer-links a {
  color: var(--text-muted);
  font-size: 0.9rem;
}

.breadcrumb {
  padding: 16px 0;
  color: var(--text-muted);
  font-size: 0.9rem;
}

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

.page-header {
  padding: 40px 0 24px;
}

.page-header h1 {
  margin: 0 0 12px;
  font-size: clamp(1.6rem, 4vw, 2.2rem);
  color: var(--text-color);
}

.page-header .lead {
  margin: 0;
  color: var(--text-muted);
  max-width: 720px;
}

@media (max-width: 640px) {
  .site-nav a {
    padding: 6px 12px;
    font-size: 13px;
  }

  .hero {
    padding: 48px 0 40px;
  }

  .content-block {
    padding: 20px;
  }
}