/* Reset & Base - Dark Mode */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

:root {
  --primary: #00b4d8;
  --primary-dark: #0096c7;
  --primary-light: #48cae4;
  --success: #22c55e;
  --warning: #f59e0b;
  --danger: #ef4444;
  --bg-dark: #0a0a0f;
  --bg-card: #12121a;
  --bg-input: #1a1a24;
  --border: #2a2a3a;
  --text: #e4e4e7;
  --text-muted: #a1a1aa;
  --text-dim: #71717a;
  --radius: 8px;
  --shadow: 0 4px 6px rgba(0, 0, 0, 0.3);
  --shadow-lg: 0 10px 25px rgba(0, 0, 0, 0.4);
}

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  background: var(--bg-dark);
  color: var(--text);
  line-height: 1.5;
  min-height: 100vh;
}

.hidden { display: none !important; }

/* Navigation */
nav {
  background: var(--bg-card);
  border-bottom: 1px solid var(--border);
  padding: 0.1rem 2rem;
  display: flex;
  justify-content: space-between;
  align-items: center;
  position: sticky;
  top: 0;
  z-index: 100;
}

.nav-brand {
  display: flex;
  align-items: center;
}

.nav-logo {
  height: 110px;
  width: auto;
}

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

.nav-links a {
  color: var(--text-muted);
  text-decoration: none;
  transition: color 0.2s;
}

.nav-links a:hover {
  color: var(--primary);
}

/* Footer */
footer {
  text-align: center;
  padding: 2rem;
  color: var(--text-dim);
  font-size: 0.875rem;
}

footer strong {
  color: var(--primary);
}

/* Auth Pages */
.auth-container {
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 2rem;
  background: linear-gradient(135deg, var(--bg-dark) 0%, #0d1117 100%);
}

.auth-box {
  background: var(--bg-card);
  border: 1px solid var(--border);
  padding: 3rem;
  border-radius: var(--radius);
  box-shadow: var(--shadow-lg);
  width: 100%;
  max-width: 500px;
  text-align: center;
}

.auth-logo {
  width: 350px;
  margin-bottom: 2rem;
}

.auth-box h1 {
  color: var(--text);
  margin-bottom: 0.25rem;
}

.auth-box .subtitle {
  color: var(--text-muted);
  margin-bottom: 2rem;
}

.auth-box form {
  text-align: left;
}

.auth-footer {
  margin-top: 2rem;
  color: var(--text-dim);
  font-size: 0.75rem;
}

.auth-footer strong {
  color: var(--primary);
}

/* Container & Layout */
.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 2rem;
}

.page-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 2rem;
  flex-wrap: wrap;
  gap: 1rem;
}

.page-header h1 {
  font-size: 1.75rem;
  color: var(--text);
}

.page-header .subtitle {
  color: var(--text-muted);
  width: 100%;
}

.header-actions {
  display: flex;
  gap: 1rem;
  align-items: center;
}

/* Cards */
.card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 1.5rem;
  margin-bottom: 1.5rem;
}

.card h2 {
  font-size: 1.125rem;
  margin-bottom: 1rem;
  color: var(--text);
}

/* Stats Grid */
.stats-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
  gap: 1rem;
}

.stat-item {
  text-align: center;
  padding: 1rem;
  background: var(--bg-input);
  border-radius: var(--radius);
  border: 1px solid var(--border);
}

.stat-value {
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--text);
}

.stat-value.positive { color: var(--success); }
.stat-value.negative { color: var(--danger); }
.stat-value.warning { color: var(--warning); }

.stat-label {
  font-size: 0.75rem;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  margin-top: 0.25rem;
}

/* Forms */
.form-group {
  margin-bottom: 1.25rem;
}

.form-group label {
  display: block;
  font-weight: 500;
  margin-bottom: 0.5rem;
  color: var(--text-muted);
}

.form-group input,
.form-group select {
  width: 100%;
  padding: 0.75rem 1rem;
  background: var(--bg-input);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  font-size: 1rem;
  color: var(--text);
  transition: border-color 0.2s, box-shadow 0.2s;
}

.form-group input:focus,
.form-group select:focus {
  outline: none;
  border-color: var(--primary);
  box-shadow: 0 0 0 3px rgba(0, 180, 216, 0.15);
}

.form-group input::placeholder {
  color: var(--text-dim);
}

.form-row {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 1rem;
}

.or-divider {
  display: block;
  text-align: center;
  color: var(--text-dim);
  margin: 0.5rem 0;
  font-size: 0.875rem;
}

.form-actions {
  margin-top: 2rem;
  display: flex;
  gap: 1rem;
}

/* File Upload */
.file-upload {
  position: relative;
}

.file-upload input[type="file"] {
  position: absolute;
  width: 100%;
  height: 100%;
  opacity: 0;
  cursor: pointer;
}

.file-upload-label {
  border: 2px dashed var(--border);
  border-radius: var(--radius);
  padding: 2rem;
  text-align: center;
  color: var(--text-muted);
  transition: border-color 0.2s, background 0.2s;
}

.file-upload-label.file-selected {
  border-color: var(--primary);
  background: rgba(0, 180, 216, 0.1);
}

.file-upload:hover .file-upload-label {
  border-color: var(--primary);
  background: var(--bg-input);
}

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0.75rem 1.5rem;
  border: none;
  border-radius: var(--radius);
  font-size: 1rem;
  font-weight: 500;
  cursor: pointer;
  transition: all 0.2s;
  text-decoration: none;
}

.btn-primary {
  background: var(--primary);
  color: #000;
}

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

.btn-secondary {
  background: var(--bg-input);
  color: var(--text);
  border: 1px solid var(--border);
}

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

.btn-danger {
  background: var(--danger);
  color: white;
}

.btn-danger:hover {
  background: #dc2626;
}

.btn-link {
  background: none;
  color: var(--primary);
  padding: 0.5rem;
}

.btn-link:hover {
  text-decoration: underline;
}

.btn-block {
  width: 100%;
}

.btn-sm {
  padding: 0.4rem 0.8rem;
  font-size: 0.875rem;
}

/* Tables */
.data-table {
  width: 100%;
  border-collapse: collapse;
}

.data-table th,
.data-table td {
  padding: 0.75rem 1rem;
  text-align: left;
  border-bottom: 1px solid var(--border);
}

.data-table th {
  background: var(--bg-input);
  font-weight: 600;
  color: var(--text-muted);
  font-size: 0.75rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.data-table tbody tr:hover {
  background: var(--bg-input);
}

.data-table .floor-penalty {
  background: rgba(239, 68, 68, 0.15);
}

.data-table .alpha-cell {
  font-weight: 700;
}

.data-table .positive { color: var(--success); }
.data-table .negative { color: var(--danger); }

/* Shift Select in Table */
.data-table select {
  padding: 0.5rem;
  background: var(--bg-input);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  font-size: 0.875rem;
  color: var(--text);
  min-width: 140px;
}

/* Batch List */
.batch-list {
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
}

.batch-item {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 1rem;
  background: var(--bg-input);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  transition: background 0.2s;
}

.batch-item:hover {
  background: var(--border);
}

.batch-info h3 {
  font-size: 1rem;
  margin-bottom: 0.25rem;
  color: var(--text);
}

.batch-meta {
  font-size: 0.875rem;
  color: var(--text-muted);
}

/* Analysis Text */
.analysis-text {
  white-space: pre-wrap;
  line-height: 1.7;
  color: var(--text-muted);
}

.analysis-text strong,
.analysis-text em {
  color: var(--text);
}

/* Messages */
.error {
  background: rgba(239, 68, 68, 0.15);
  border: 1px solid var(--danger);
  color: var(--danger);
  padding: 1rem;
  border-radius: var(--radius);
  margin-top: 1rem;
}

.success {
  background: rgba(34, 197, 94, 0.15);
  border: 1px solid var(--success);
  color: var(--success);
  padding: 1rem;
  border-radius: var(--radius);
  margin-top: 1rem;
}

.loading {
  text-align: center;
  color: var(--text-muted);
  padding: 2rem;
}

/* Empty State */
.empty-state {
  text-align: center;
  padding: 3rem;
  color: var(--text-muted);
}

.empty-state h3 {
  margin-bottom: 0.5rem;
  color: var(--text);
}

/* Responsive */
@media (max-width: 768px) {
  .container {
    padding: 1rem;
  }
  
  nav {
    padding: 0.75rem 1rem;
  }
  
  .nav-logo {
    height: 32px;
  }
  
  .page-header {
    flex-direction: column;
    align-items: flex-start;
  }
  
  .data-table {
    font-size: 0.875rem;
  }
  
  .data-table th,
  .data-table td {
    padding: 0.5rem;
  }
  
  .stats-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}