:root {
  --bg-primary: #0f172a;
  --bg-secondary: #1e293b;
  --accent: #3b82f6;
  --accent-hover: #2563eb;
  --text-primary: #f8fafc;
  --text-secondary: #94a3b8;
  --success: #10b981;
  --warning: #f59e0b;
  --danger: #ef4444;
}

* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
  font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
}

body {
  background-color: var(--bg-primary);
  color: var(--text-primary);
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

header {
  background-color: var(--bg-secondary);
  border-bottom: 1px solid #334155;
  position: sticky;
  top: 0;
  z-index: 100;
}

.nav-container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 1rem 2rem;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.logo-link {
  text-decoration: none;
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.logo-text {
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--accent);
  letter-spacing: 1px;
}

.nav-menu {
  display: flex;
  list-style: none;
  gap: 1.5rem;
}

.nav-link {
  color: var(--text-secondary);
  text-decoration: none;
  font-weight: 500;
  transition: color 0.2s ease;
}

.nav-link:hover, .nav-link.active {
  color: var(--text-primary);
  border-bottom: 2px solid var(--accent);
  padding-bottom: 0.25rem;
}

.status-badge {
  background-color: var(--success);
  color: #fff;
  padding: 0.25rem 0.75rem;
  border-radius: 9999px;
  font-size: 0.8rem;
  font-weight: bold;
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.status-badge.offline {
  background-color: var(--warning);
}

main {
  flex: 1;
  max-width: 1200px;
  margin: 0 auto;
  padding: 3rem 2rem;
  width: 100%;
}

.hero {
  text-align: center;
  padding: 3rem 0;
}

.hero h1 {
  font-size: 3rem;
  margin-bottom: 1rem;
  background: linear-gradient(135deg, #60a5fa, #3b82f6);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.hero p {
  font-size: 1.25rem;
  color: var(--text-secondary);
  max-width: 600px;
  margin: 0 auto 2rem;
}

.grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 2rem;
  margin-top: 2rem;
}

.card {
  background-color: var(--bg-secondary);
  border: 1px solid #334155;
  border-radius: 12px;
  padding: 2rem;
  transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.card:hover {
  transform: translateY(-5px);
  box-shadow: 0 10px 15px -3px rgba(0, 0, 0, 0.3);
}

.card h2 {
  margin-bottom: 1rem;
  color: var(--text-primary);
}

.card p {
  color: var(--text-secondary);
  line-height: 1.6;
}

/* Offline Task Workspace feature css */
.workspace {
  background-color: var(--bg-secondary);
  padding: 2rem;
  border-radius: 12px;
  border: 1px solid #334155;
  margin-top: 3rem;
}

.workspace-title {
  margin-bottom: 1rem;
}

.input-group {
  display: flex;
  gap: 0.5rem;
  margin-bottom: 1.5rem;
}

input, textarea {
  width: 100%;
  padding: 0.75rem 1rem;
  border-radius: 8px;
  border: 1px solid #334155;
  background-color: var(--bg-primary);
  color: var(--text-primary);
  font-size: 1rem;
}

input:focus, textarea:focus {
  outline: none;
  border-color: var(--accent);
}

button {
  background-color: var(--accent);
  color: white;
  border: none;
  padding: 0.75rem 1.5rem;
  border-radius: 8px;
  font-weight: 600;
  cursor: pointer;
  transition: background-color 0.2s ease;
}

button:hover {
  background-color: var(--accent-hover);
}

.notes-list {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1rem;
}

.note-item {
  background-color: var(--bg-primary);
  padding: 1rem;
  border-radius: 8px;
  border-left: 4px solid var(--accent);
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.note-item button {
  background-color: var(--danger);
  padding: 0.4rem 0.8rem;
  font-size: 0.8rem;
}

.note-item button:hover {
  background-color: #dc2626;
}

form.contact-form {
  display: flex;
  flex-direction: column;
  gap: 1rem;
  max-width: 600px;
  margin: 0 auto;
}

footer {
  background-color: var(--bg-secondary);
  border-top: 1px solid #334155;
  padding: 1.5rem 2rem;
  text-align: center;
  color: var(--text-secondary);
  margin-top: auto;
}

@media (max-width: 768px) {
  .nav-container {
    flex-direction: column;
    gap: 1rem;
  }
  .nav-menu {
    width: 100%;
    justify-content: center;
  }
}