:root {
  --color-primary: #2563eb;
  --color-primary-hover: #1d4ed8;
  --color-text: #1f2937;
  --color-text-muted: #6b7280;
  --color-bg: #ffffff;
  --color-surface: #f9fafb;
  --color-border: #e5e7eb;
  --color-card-bg: #ffffff;
  --color-input-bg: #ffffff;
  --color-input-border: #d1d5db;
  --color-footer-bg: #f3f4f6;
  --gradient-bg: linear-gradient(135deg, #e0e7ff 0%, #dbeafe 50%, #ede9fe 100%);
  --shadow-card: 0 1px 3px rgba(0,0,0,0.1);
  --shadow-lg: 0 10px 30px rgba(0,0,0,0.1);
  --transition-speed: 0.3s;
}

[data-theme="dark"] {
  --color-text: #e5e7eb;
  --color-text-muted: #9ca3af;
  --color-bg: #1a1a2e;
  --color-surface: #16213e;
  --color-border: #2d3748;
  --color-card-bg: #16213e;
  --color-input-bg: #0f3460;
  --color-input-border: #2d3748;
  --color-footer-bg: #0f0f23;
  --gradient-bg: linear-gradient(135deg, #1a1a2e 0%, #16213e 50%, #0f3460 100%);
  --shadow-card: 0 1px 3px rgba(0,0,0,0.3);
  --shadow-lg: 0 10px 30px rgba(0,0,0,0.4);
}

* {
  transition: background-color var(--transition-speed), color var(--transition-speed), border-color var(--transition-speed);
}

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
  background-color: var(--color-bg);
  color: var(--color-text);
  min-height: 100vh;
  margin: 0;
  display: flex;
  flex-direction: column;
}

.search-page {
  background: var(--gradient-bg);
}

.auth-page, .dashboard-page {
  background-color: var(--color-bg);
}

/* Theme Toggle */
.theme-toggle {
  position: fixed;
  top: 16px;
  right: 16px;
  z-index: 1000;
  width: 44px;
  height: 44px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--color-card-bg);
  border: 1px solid var(--color-border);
  box-shadow: var(--shadow-card);
  cursor: pointer;
  font-size: 1.2rem;
}

/* Top Nav */
.top-nav {
  position: fixed;
  top: 16px;
  right: 72px;
  z-index: 999;
  display: flex;
  align-items: center;
  background: var(--color-card-bg);
  padding: 6px 16px;
  border-radius: 24px;
  box-shadow: var(--shadow-card);
  border: 1px solid var(--color-border);
  font-size: 0.875rem;
}

/* Search Hero */
.search-hero {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  min-height: 80vh;
  padding-top: 60px;
}

.logo-container {
  width: 120px;
  height: 120px;
}

.logo {
  width: 100%;
  height: 100%;
}

.brand-title {
  font-size: 3rem;
  font-weight: 800;
  color: var(--color-primary);
  margin-bottom: 0.25rem;
}

.brand-subtitle {
  font-size: 1.15rem;
}

/* Search Form */
.search-form .input-group {
  max-width: 680px;
  border-radius: 12px;
  overflow: hidden;
}

.search-form .form-control {
  border: 2px solid var(--color-input-border);
  background: var(--color-input-bg);
  color: var(--color-text);
  padding: 12px 20px;
  font-size: 1.1rem;
  border-radius: 12px 0 0 12px !important;
}

.search-form .form-control:focus {
  border-color: var(--color-primary);
  box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.15);
}

.search-form .btn-primary {
  background: var(--color-primary);
  border-color: var(--color-primary);
  font-size: 1.1rem;
  font-weight: 600;
  padding: 12px 28px;
  border-radius: 0 12px 12px 0 !important;
}

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

/* Section Cards */
.section-card {
  background: var(--color-card-bg);
  border-radius: 12px;
  box-shadow: var(--shadow-card);
  border: 1px solid var(--color-border);
  padding: 20px 24px;
  max-width: 680px;
  margin-left: auto;
  margin-right: auto;
}

.section-title {
  display: flex;
  align-items: center;
  font-weight: 600;
  margin-bottom: 12px;
  color: var(--color-text);
}

.list-group-item {
  background: transparent;
  border-color: var(--color-border);
  color: var(--color-text);
}

.list-group-item:hover {
  background: var(--color-surface);
}

.history-title {
  font-weight: 500;
  color: var(--color-text);
}

/* Auth Cards */
.auth-wrapper {
  display: flex;
  align-items: center;
  justify-content: center;
  min-height: 100vh;
  padding: 20px;
}

.auth-card {
  width: 100%;
  max-width: 440px;
  border: 1px solid var(--color-border);
  border-radius: 16px;
  background: var(--color-card-bg);
}

.auth-card .form-control {
  background: var(--color-input-bg);
  border-color: var(--color-input-border);
  color: var(--color-text);
}

.auth-card .form-control:focus {
  border-color: var(--color-primary);
  box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.15);
}

/* Buttons */
.btn-primary {
  background: var(--color-primary);
  border-color: var(--color-primary);
}

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

/* Dashboard */
.dashboard-page .card {
  background: var(--color-card-bg);
  border: 1px solid var(--color-border);
  border-radius: 12px;
}

.dashboard-page .card-header {
  background: transparent;
  border-bottom-color: var(--color-border);
  font-weight: 600;
}

.dashboard-page .table {
  color: var(--color-text);
}

.dashboard-page .table thead th {
  border-bottom-color: var(--color-border);
  color: var(--color-text-muted);
  font-size: 0.8rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.dashboard-page .table td {
  border-bottom-color: var(--color-border);
  vertical-align: middle;
}

.dashboard-page .list-group-item {
  background: transparent;
  border-color: var(--color-border);
  color: var(--color-text);
}

.search-form-sm .form-control {
  background: var(--color-input-bg);
  border-color: var(--color-input-border);
  color: var(--color-text);
}

/* Footer */
.footer {
  margin-top: auto;
  text-align: center;
  padding: 24px;
  background: var(--color-footer-bg);
  border-top: 1px solid var(--color-border);
  color: var(--color-text-muted);
  font-size: 0.875rem;
}

/* Toast */
.toast-container {
  z-index: 9999;
}

/* Loading Spinner */
.spinner-overlay {
  position: fixed;
  inset: 0;
  background: rgba(0,0,0,0.3);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 10000;
}

/* Responsive */
@media (max-width: 768px) {
  .brand-title {
    font-size: 2rem;
  }

  .search-hero {
    min-height: 70vh;
  }

  .top-nav {
    right: 64px;
    padding: 4px 10px;
    font-size: 0.8rem;
  }

  .section-card {
    margin-left: 12px;
    margin-right: 12px;
  }

  .theme-toggle {
    width: 36px;
    height: 36px;
    font-size: 1rem;
  }
}

@media (max-width: 576px) {
  .search-form .input-group {
    flex-direction: column;
  }

  .search-form .form-control {
    border-radius: 12px 12px 0 0 !important;
  }

  .search-form .btn-primary {
    border-radius: 0 0 12px 12px !important;
  }
}