:root {
    --bg-color: #f9fafb;
    --card-bg: #ffffff;
    --text-primary: #111827;
    --text-secondary: #4b5563;
    --accent-color: #000000;
    --accent-hover: #1f2937;
    --border-color: #e5e7eb;
    --success-color: #10b981;
    --danger-color: #ef4444;
    --spacing-sm: 0.5rem;
    --spacing-md: 1rem;
    --spacing-lg: 1.5rem;
    --spacing-xl: 2rem;
    --max-width: 1200px;
}

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

body {
    font-family: 'Inter', system-ui, -apple-system, sans-serif;
    color: var(--text-primary);
    background-color: var(--bg-color);
    line-height: 1.5;
    -webkit-font-smoothing: antialiased;
}

.container {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: var(--spacing-xl);
}

.hidden {
    display: none !important;
}

/* Header */
header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding-bottom: var(--spacing-xl);
    border-bottom: 1px solid var(--border-color);
    margin-bottom: var(--spacing-xl);
}

.logo {
    font-size: 1.5rem;
    font-weight: 800;
    letter-spacing: -1px;
    text-transform: lowercase;
}

.header-actions {
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
}

.user-info {
    font-size: 0.9rem;
    color: var(--text-secondary);
    font-weight: 600;
}

/* Buttons */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 0.75rem 1.5rem;
    border-radius: 9999px;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.2s ease;
    border: none;
    font-size: 0.9rem;
}

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

.btn-primary:hover {
    background-color: var(--accent-hover);
    transform: translateY(-1px);
}

.btn-secondary {
    background-color: #f3f4f6;
    color: var(--text-primary);
}

.btn-secondary:hover {
    background-color: #e5e7eb;
}

.btn-sm {
    padding: 0.5rem 1rem;
    font-size: 0.8rem;
}

/* Typography */
h1 {
    font-size: 2.5rem;
    font-weight: 800;
    letter-spacing: -0.02em;
    margin-bottom: var(--spacing-lg);
}

h2 {
    font-size: 1.5rem;
    font-weight: 700;
    margin-bottom: var(--spacing-md);
}

h3 {
    font-size: 0.875rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    color: var(--text-secondary);
    margin-bottom: 0.5rem;
}

/* Metrics Grid */
.metrics-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
    gap: var(--spacing-lg);
    margin-bottom: var(--spacing-xl);
}

.metric-card {
    background: var(--card-bg);
    padding: var(--spacing-lg);
    border-radius: 20px;
    border: 1px solid var(--border-color);
    transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.metric-card:hover {
    transform: translateY(-2px);
    box-shadow: 0 10px 20px rgba(0, 0, 0, 0.05);
}

.metric-card p {
    font-size: 2rem;
    font-weight: 800;
    letter-spacing: -0.02em;
    margin-bottom: 0.25rem;
}

.metric-sub {
    font-size: 0.75rem;
    color: var(--text-secondary);
}

.metric-card.highlight {
    background: var(--accent-color);
    color: white;
    border-color: var(--accent-color);
}

.metric-card.highlight h3,
.metric-card.highlight .metric-sub {
    color: rgba(255, 255, 255, 0.7);
}

/* Section Card */
.section-card {
    background: var(--card-bg);
    padding: var(--spacing-lg);
    border-radius: 20px;
    border: 1px solid var(--border-color);
}

/* Table */
.table-responsive {
    overflow-x: auto;
}

table {
    width: 100%;
    border-collapse: collapse;
    text-align: left;
    font-size: 0.95rem;
}

th, td {
    padding: var(--spacing-md);
    border-bottom: 1px solid var(--border-color);
}

th {
    font-weight: 600;
    color: var(--text-secondary);
    font-size: 0.85rem;
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

tbody tr:hover {
    background-color: #f9fafb;
}

.badge {
    display: inline-flex;
    padding: 0.25rem 0.5rem;
    border-radius: 9999px;
    font-size: 0.75rem;
    font-weight: 600;
    text-transform: uppercase;
}

.badge-monthly {
    background-color: #e0f2fe;
    color: #0369a1;
}

.badge-single {
    background-color: #fef3c7;
    color: #b45309;
}

/* Login Overlay */
.overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(255, 255, 255, 0.8);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 9999;
    transition: opacity 0.3s ease;
}

.login-card {
    background: var(--card-bg);
    padding: 3rem;
    border-radius: 32px;
    border: 1px solid var(--border-color);
    box-shadow: 0 20px 40px rgba(0, 0, 0, 0.1);
    max-width: 400px;
    width: 90%;
    text-align: center;
}

.login-card .logo {
    font-size: 2rem;
    margin-bottom: 1.5rem;
}

.login-card h2 {
    margin-bottom: 0.5rem;
}

.login-card p {
    color: var(--text-secondary);
    margin-bottom: 2rem;
    font-size: 0.95rem;
}

form {
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

input[type="password"] {
    padding: 0.75rem 1rem;
    border-radius: 9999px;
    border: 1px solid var(--border-color);
    font-size: 1rem;
    text-align: center;
    transition: border-color 0.2s ease;
}

input[type="password"]:focus {
    outline: none;
    border-color: var(--accent-color);
}

.error-message {
    color: var(--danger-color);
    font-size: 0.85rem;
    margin-top: 0.5rem;
    font-weight: 600;
}

/* Responsive */
@media (max-width: 768px) {
    .container {
        padding: var(--spacing-md);
    }
    
    h1 {
        font-size: 2rem;
    }
    
    .login-card {
        padding: 2rem;
    }
}

/* Inline Form */
.inline-form {
    display: flex;
    flex-wrap: wrap;
    gap: var(--spacing-md);
    align-items: center;
}

.inline-form input,
.inline-form select {
    padding: 0.75rem 1rem;
    border-radius: 9999px;
    border: 1px solid var(--border-color);
    font-size: 0.9rem;
    min-width: 150px;
    flex: 1;
}

.inline-form input:focus,
.inline-form select:focus {
    outline: none;
    border-color: var(--accent-color);
}

@media (max-width: 768px) {
    .inline-form {
        flex-direction: column;
        align-items: stretch;
    }
    .inline-form input,
    .inline-form select {
        width: 100%;
    }
}