:root {
  --primary: #5C7CFA;
  --primary-light: #7B93FF;
  --primary-dark: #3D5AFE;
  --bg: #F8F9FA;
  --bg-white: #FFFFFF;
  --text: #212529;
  --text-secondary: #6C757D;
  --text-light: #ADB5BD;
  --border: #DEE2E6;
  --max-width: 1100px;
  --radius: 12px;
}

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

html {
  scroll-behavior: smooth;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  color: var(--text);
  background: var(--bg);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

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

a:hover {
  text-decoration: underline;
}

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

/* ── Navigation ── */

.nav {
  position: sticky;
  top: 0;
  background: var(--bg-white);
  border-bottom: 1px solid var(--border);
  z-index: 100;
}

.nav-inner {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 24px;
  height: 60px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.nav-logo {
  font-size: 1.4rem;
  font-weight: 700;
  color: var(--primary);
  text-decoration: none;
}

.nav-logo:hover {
  text-decoration: none;
}

.nav-links {
  display: flex;
  gap: 24px;
  list-style: none;
}

.nav-links a {
  color: var(--text-secondary);
  font-size: 0.95rem;
  font-weight: 500;
  transition: color 0.2s;
}

.nav-links a:hover {
  color: var(--primary);
  text-decoration: none;
}

/* ── Hero ── */

.hero {
  background: linear-gradient(135deg, var(--primary) 0%, var(--primary-light) 100%);
  color: #fff;
  text-align: center;
  padding: 80px 24px 64px;
}

.hero h1 {
  font-size: 2.8rem;
  font-weight: 800;
  line-height: 1.15;
  margin-bottom: 16px;
}

.hero p {
  font-size: 1.15rem;
  max-width: 560px;
  margin: 0 auto 32px;
  opacity: 0.92;
}

.hero-badge {
  display: inline-block;
  transition: opacity 0.2s;
}

.hero-badge:hover {
  opacity: 0.85;
}

.hero-badge img {
  height: 56px;
}

/* ── Section shared ── */

.section {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 64px 24px;
}

.section-title {
  text-align: center;
  font-size: 1.8rem;
  font-weight: 700;
  margin-bottom: 40px;
}

/* ── Features ── */

.features-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(240px, 1fr));
  gap: 24px;
}

.feature-card {
  background: var(--bg-white);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 28px 24px;
  transition: box-shadow 0.2s;
}

.feature-card:hover {
  box-shadow: 0 4px 20px rgba(0, 0, 0, 0.06);
}

.feature-icon {
  font-size: 1.6rem;
  margin-bottom: 12px;
}

.feature-card h3 {
  font-size: 1.05rem;
  font-weight: 600;
  margin-bottom: 8px;
}

.feature-card p {
  color: var(--text-secondary);
  font-size: 0.92rem;
  line-height: 1.55;
}

/* ── Platforms ── */

.platforms {
  text-align: center;
  background: var(--bg-white);
  border-top: 1px solid var(--border);
  border-bottom: 1px solid var(--border);
}

.platform-icons {
  display: flex;
  justify-content: center;
  gap: 48px;
  flex-wrap: wrap;
  margin-bottom: 20px;
}

.platform-item {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 8px;
  color: var(--text-secondary);
  font-size: 0.9rem;
  font-weight: 500;
}

.platform-item svg {
  width: 40px;
  height: 40px;
  fill: var(--primary);
}

.platforms p {
  color: var(--text-secondary);
  font-size: 0.95rem;
}

/* ── Footer ── */

.footer {
  background: var(--text);
  color: var(--text-light);
  text-align: center;
  padding: 40px 24px;
  font-size: 0.88rem;
}

.footer a {
  color: var(--text-light);
}

.footer a:hover {
  color: #fff;
}

.footer-links {
  margin-bottom: 12px;
  display: flex;
  justify-content: center;
  gap: 24px;
}

/* ── Privacy Policy page ── */

.privacy {
  max-width: 780px;
  margin: 0 auto;
  padding: 48px 24px 80px;
}

.privacy h1 {
  font-size: 2rem;
  font-weight: 700;
  margin-bottom: 8px;
}

.privacy .effective-date {
  color: var(--text-secondary);
  margin-bottom: 32px;
  font-size: 0.95rem;
}

.privacy h2 {
  font-size: 1.3rem;
  font-weight: 600;
  margin-top: 36px;
  margin-bottom: 12px;
  color: var(--text);
}

.privacy h3 {
  font-size: 1.05rem;
  font-weight: 600;
  margin-top: 20px;
  margin-bottom: 8px;
}

.privacy p,
.privacy li {
  color: var(--text-secondary);
  font-size: 0.95rem;
  line-height: 1.7;
  margin-bottom: 12px;
}

.privacy ul,
.privacy ol {
  padding-left: 24px;
  margin-bottom: 12px;
}

.privacy li {
  margin-bottom: 6px;
}

.privacy a {
  word-break: break-word;
}

.privacy .toc {
  background: var(--bg-white);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 20px 24px;
  margin-bottom: 32px;
}

.privacy .toc h2 {
  font-size: 1.05rem;
  margin-top: 0;
  margin-bottom: 12px;
}

.privacy .toc ol {
  margin-bottom: 0;
}

.privacy .toc li {
  margin-bottom: 4px;
}

/* ── 404 ── */

.error-page {
  min-height: 60vh;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  text-align: center;
  padding: 64px 24px;
}

.error-page h1 {
  font-size: 4rem;
  font-weight: 800;
  color: var(--primary);
  margin-bottom: 8px;
}

.error-page p {
  color: var(--text-secondary);
  font-size: 1.1rem;
  margin-bottom: 24px;
}

.btn {
  display: inline-block;
  background: var(--primary);
  color: #fff;
  padding: 12px 28px;
  border-radius: 8px;
  font-weight: 600;
  font-size: 0.95rem;
  text-decoration: none;
  transition: background 0.2s;
}

.btn:hover {
  background: var(--primary-dark);
  text-decoration: none;
}

/* ── Responsive ── */

@media (max-width: 768px) {
  .hero h1 {
    font-size: 2rem;
  }

  .hero p {
    font-size: 1rem;
  }

  .section-title {
    font-size: 1.5rem;
  }

  .features-grid {
    grid-template-columns: 1fr;
  }

  .platform-icons {
    gap: 32px;
  }

  .nav-links {
    gap: 16px;
  }
}