:root {
  --primary: #2563EB;
  --primary-hover: #1D4ED8;
  --bg: #F8FAFC;
  --surface: #FFFFFF;
  --text-main: #0F172A;
  --text-muted: #64748B;
  --border: #E2E8F0;
  
  --success: #16A34A;
  --warning: #F59E0B;
  --danger: #DC2626;
  --info: #3B82F6;
  
  --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.05);
  --shadow: 0 4px 6px -1px rgb(0 0 0 / 0.1), 0 2px 4px -2px rgb(0 0 0 / 0.1);
  --radius: 12px;
  --radius-sm: 8px;
}

[data-theme="dark"] {
  --bg: #0F172A;
  --surface: #1E293B;
  --text-main: #F8FAFC;
  --text-muted: #94A3B8;
  --border: #334155;
  --shadow: 0 4px 6px -1px rgb(0 0 0 / 0.3);
}

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

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  background-color: var(--bg);
  color: var(--text-main);
  line-height: 1.6;
  transition: background-color 0.3s, color 0.3s;
}

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

header {
  background-color: var(--surface);
  border-bottom: 1px solid var(--border);
  position: sticky;
  top: 0;
  z-index: 50;
}

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

.logo {
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--primary);
  display: flex;
  align-items: center;
  gap: 0.5rem;
  text-decoration: none !important;
}

.nav-links {
  display: flex;
  gap: 1.5rem;
  align-items: center;
}

.nav-links a {
  color: var(--text-main);
  font-weight: 500;
}
.nav-links a:hover {
  color: var(--primary);
  text-decoration: none;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0.75rem 1.5rem;
  background-color: var(--primary);
  color: white !important;
  border: none;
  border-radius: var(--radius-sm);
  font-weight: 600;
  cursor: pointer;
  transition: background-color 0.2s;
  text-decoration: none !important;
  gap: 0.5rem;
  font-size: 1rem;
}

.btn:hover {
  background-color: var(--primary-hover);
}

.btn-outline {
  background-color: transparent;
  border: 1px solid var(--primary);
  color: var(--primary) !important;
}
.btn-outline:hover {
  background-color: var(--primary);
  color: white !important;
}

.main-container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 2rem 1rem;
  min-height: calc(100vh - 200px);
}

.hero {
  text-align: center;
  padding: 4rem 1rem;
}

.hero h1 {
  font-size: 3rem;
  font-weight: 800;
  margin-bottom: 1rem;
  color: var(--text-main);
}

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

.card {
  background-color: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 1.5rem;
  box-shadow: var(--shadow-sm);
  transition: transform 0.2s, box-shadow 0.2s;
  display: flex;
  flex-direction: column;
}

.card:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow);
}

.card-icon {
  width: 48px;
  height: 48px;
  background-color: rgb(37 99 235 / 0.1);
  color: var(--primary);
  border-radius: var(--radius-sm);
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 1rem;
}
.card-icon svg {
  width: 24px;
  height: 24px;
}

.card h3 {
  font-size: 1.25rem;
  margin-bottom: 0.5rem;
  color: var(--text-main);
}

.card p {
  color: var(--text-muted);
  margin-bottom: 1.5rem;
  flex-grow: 1;
}

.grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
  gap: 1.5rem;
}

/* Tool Page Specifics */
.tool-header {
  margin-bottom: 2rem;
}

.tool-header h1 {
  font-size: 2rem;
  margin-bottom: 0.5rem;
}

.form-group {
  margin-bottom: 1.5rem;
}

.form-group label {
  display: block;
  font-weight: 500;
  margin-bottom: 0.5rem;
}

.form-control {
  width: 100%;
  padding: 0.75rem;
  background-color: var(--bg);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  color: var(--text-main);
  font-family: inherit;
  font-size: 1rem;
}
.form-control:focus {
  outline: none;
  border-color: var(--primary);
  box-shadow: 0 0 0 2px rgb(37 99 235 / 0.2);
}

textarea.form-control {
  min-height: 120px;
  resize: vertical;
}

.result-box {
  margin-top: 2rem;
  padding: 1.5rem;
  background-color: var(--bg);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  display: none;
}
.result-box.active {
  display: block;
}

.badge {
  display: inline-block;
  padding: 0.25rem 0.5rem;
  border-radius: 999px;
  font-size: 0.75rem;
  font-weight: 600;
  text-transform: uppercase;
}
.badge.success { background-color: rgb(22 163 74 / 0.1); color: var(--success); }
.badge.warning { background-color: rgb(245 158 11 / 0.1); color: var(--warning); }
.badge.danger { background-color: rgb(220 38 38 / 0.1); color: var(--danger); }
.badge.info { background-color: rgb(59 130 246 / 0.1); color: var(--info); }

footer {
  background-color: var(--surface);
  border-top: 1px solid var(--border);
  padding: 3rem 1rem 1rem;
  margin-top: 4rem;
}

.footer-grid {
  max-width: 1200px;
  margin: 0 auto;
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 2rem;
  margin-bottom: 2rem;
}

.footer-col h4 {
  margin-bottom: 1rem;
  color: var(--text-main);
}
.footer-col ul {
  list-style: none;
}
.footer-col ul li {
  margin-bottom: 0.5rem;
}
.footer-col ul a {
  color: var(--text-muted);
}
.footer-col ul a:hover {
  color: var(--primary);
}

.copyright {
  text-align: center;
  color: var(--text-muted);
  border-top: 1px solid var(--border);
  padding-top: 1rem;
  max-width: 1200px;
  margin: 0 auto;
}

.theme-toggle {
  background: none;
  border: none;
  color: var(--text-main);
  cursor: pointer;
  padding: 0.5rem;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: 50%;
}
.theme-toggle:hover {
  background-color: var(--bg);
}

.hamburger {
  display: none;
  background: none;
  border: none;
  color: var(--text-main);
  font-size: 1.5rem;
  cursor: pointer;
}

.search-bar {
  display: flex;
  margin-bottom: 2rem;
  gap: 0.5rem;
}

.search-bar input {
  flex-grow: 1;
}

/* Category Filters */
.filters {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  margin-bottom: 2rem;
}
.filter-btn {
  padding: 0.5rem 1rem;
  background-color: var(--surface);
  border: 1px solid var(--border);
  border-radius: 999px;
  color: var(--text-main);
  cursor: pointer;
  font-size: 0.875rem;
}
.filter-btn.active, .filter-btn:hover {
  background-color: var(--primary);
  color: white;
  border-color: var(--primary);
}

@media (max-width: 768px) {
  .nav-links {
    display: none;
    flex-direction: column;
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    background-color: var(--surface);
    border-bottom: 1px solid var(--border);
    padding: 1rem;
  }
  .nav-links.active {
    display: flex;
  }
  .hamburger {
    display: block;
  }
  .hero h1 {
    font-size: 2rem;
  }
}