:root {
  --bg: #18191a;
  --sidebar: #222327;
  --card: #23272f;
  --accent: #1da1f2;
  --text: #f5f6fa;
  --muted: #8899a6;
  --border: #2f3336;
  --radius: 18px;
  --shadow: 0 2px 16px 0 rgba(0, 0, 0, 0.12);
}

body {
  margin: 0;
  font-family: 'Inter', 'Segoe UI', Arial, sans-serif;
  background: var(--bg);
  color: var(--text);
  min-height: 100vh;
  display: flex;
}

.sidebar {
  background: var(--sidebar);
  width: 260px;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  padding: 32px 24px 24px 24px;
  box-shadow: var(--shadow);
}
.logo {
  font-size: 2rem;
  font-weight: 700;
  margin-bottom: 40px;
  letter-spacing: -1px;
}
.sidebar nav ul {
  list-style: none;
  padding: 0;
  margin: 0 0 60px 0;
}
.sidebar nav ul li {
  margin-bottom: 18px;
}
.sidebar nav ul li a {
  color: var(--text);
  text-decoration: none;
  font-size: 1.1rem;
  opacity: 0.85;
  transition: color 0.2s;
}
.sidebar nav ul li a:hover {
  color: var(--accent);
}
.cta {
  background: var(--accent);
  color: #fff;
  border: none;
  border-radius: var(--radius);
  padding: 14px 0;
  width: 100%;
  font-size: 1.1rem;
  font-weight: 600;
  cursor: pointer;
  margin-top: 0;
  margin-bottom: 0;
  box-shadow: var(--shadow);
  transition: background 0.2s;
}
.cta:hover {
  background: #0d8ddb;
}

.main-content {
  flex: 1;
  padding: 48px 0 0 0;
  max-width: 800px;
  margin: 0 auto;
}
.hero {
  text-align: left;
  margin-bottom: 48px;
}
.hero h1 {
  font-size: 2.8rem;
  font-weight: 800;
  margin-bottom: 12px;
  letter-spacing: -2px;
}
.subtitle {
  color: var(--muted);
  font-size: 1.2rem;
  margin-bottom: 28px;
}
.main-cta {
  max-width: 220px;
  margin-top: 8px;
}
.features {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 32px 24px;
  margin-bottom: 56px;
}
.feature h2 {
  font-size: 1.1rem;
  margin-bottom: 6px;
  color: var(--accent);
}
.feature p {
  color: var(--muted);
  font-size: 1rem;
  margin: 0;
}
.preview {
  display: flex;
  justify-content: center;
  align-items: flex-start;
}
.mockup-card {
  background: var(--card);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 24px 22px 18px 22px;
  width: 370px;
  margin-top: 12px;
  border: 1px solid var(--border);
}
.mockup-header {
  display: flex;
  align-items: center;
  margin-bottom: 12px;
}
.mockup-avatar {
  width: 48px;
  height: 48px;
  border-radius: 50%;
  background: linear-gradient(135deg, #1da1f2 40%, #23272f 100%);
  margin-right: 14px;
}
.mockup-name {
  font-weight: 700;
  font-size: 1.1rem;
  margin-right: 8px;
}
.mockup-handle {
  color: var(--muted);
  font-size: 0.98rem;
}
.mockup-body {
  font-size: 1.08rem;
  margin-bottom: 14px;
}
.mockup-footer {
  color: var(--muted);
  font-size: 0.95rem;
  display: flex;
  gap: 8px;
  align-items: center;
}
@media (max-width: 900px) {
  .main-content {
    padding: 32px 8px 0 0;
  }
  .features {
    grid-template-columns: 1fr;
  }
  .sidebar {
    width: 70px;
    padding: 24px 8px;
  }
  .logo {
    font-size: 1.2rem;
    margin-bottom: 24px;
  }
  .sidebar nav ul li {
    margin-bottom: 10px;
  }
  .cta {
    font-size: 1rem;
    padding: 10px 0;
  }
}
@media (max-width: 600px) {
  body {
    flex-direction: column;
  }
  .sidebar {
    width: 100vw;
    flex-direction: row;
    align-items: center;
    justify-content: space-between;
    min-height: 0;
    padding: 10px 12px;
  }
  .main-content {
    padding: 18px 4px 0 4px;
  }
  .features {
    gap: 18px 0;
  }
  .mockup-card {
    width: 98vw;
  }
}