/* ============================================
   S9S URL Shortener - Main Styles
   ============================================ */

:root {
    --primary: #2563eb;
    --primary-dark: #1d4ed8;
    --secondary: #64748b;
    --success: #22c55e;
    --danger: #ef4444;
    --warning: #f59e0b;
    
    --bg-dark: #0f172a;
    --bg-card: #1e293b;
    --bg-hover: #334155;
    
    --text-primary: #f8fafc;
    --text-secondary: #94a3b8;
    --text-muted: #64748b;
    
    --border: #334155;
    --radius: 8px;
    --radius-lg: 12px;
    
    --sidebar-width: 260px;
}

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

html, body {
    height: 100%;
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, sans-serif;
    background: var(--bg-dark);
    color: var(--text-primary);
    line-height: 1.6;
}

/* ============================================
   Layout
   ============================================ */

.app-container {
    display: flex;
    min-height: 100vh;
}

.sidebar {
    width: var(--sidebar-width);
    background: var(--bg-card);
    border-right: 1px solid var(--border);
    display: flex;
    flex-direction: column;
    position: fixed;
    height: 100vh;
}

.sidebar-header {
    padding: 24px;
    border-bottom: 1px solid var(--border);
}

.logo {
    text-decoration: none;
    display: flex;
    flex-direction: column;
}

.logo-text {
    font-size: 28px;
    font-weight: 700;
    color: var(--primary);
    letter-spacing: -1px;
}

.logo-subtext {
    font-size: 12px;
    color: var(--text-secondary);
    text-transform: uppercase;
    letter-spacing: 1px;
}

.nav-menu {
    list-style: none;
    padding: 16px 0;
    flex: 1;
}

.nav-menu li a {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 12px 24px;
    color: var(--text-secondary);
    text-decoration: none;
    transition: all 0.2s;
}

.nav-menu li a:hover {
    background: var(--bg-hover);
    color: var(--text-primary);
}

.nav-menu li a.active {
    background: var(--primary);
    color: white;
}

.nav-icon {
    font-size: 18px;
}

.sidebar-footer {
    padding: 16px 24px;
    border-top: 1px solid var(--border);
}

.user-info {
    display: flex;
    flex-direction: column;
    gap: 8px;
}

.user-name {
    font-size: 14px;
    color: var(--text-primary);
}

.sign-out {
    font-size: 12px;
    color: var(--text-muted);
    text-decoration: none;
}

.sign-out:hover {
    color: var(--danger);
}

.main-content {
    flex: 1;
    margin-left: var(--sidebar-width);
    padding: 32px;
    max-width: 1400px;
}

/* ============================================
   Cards
   ============================================ */

.card {
    background: var(--bg-card);
    border-radius: var(--radius-lg);
    padding: 24px;
    border: 1px solid var(--border);
}

.card-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 20px;
}

.card-title {
    font-size: 18px;
    font-weight: 600;
}

/* ============================================
   Stats Grid
   ============================================ */

.stats-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 20px;
    margin-bottom: 32px;
}

.stat-card {
    background: var(--bg-card);
    border-radius: var(--radius-lg);
    padding: 20px;
    border: 1px solid var(--border);
}

.stat-label {
    font-size: 14px;
    color: var(--text-secondary);
    margin-bottom: 8px;
}

.stat-value {
    font-size: 32px;
    font-weight: 700;
    color: var(--text-primary);
}

.stat-change {
    font-size: 12px;
    margin-top: 8px;
}

.stat-change.positive {
    color: var(--success);
}

.stat-change.negative {
    color: var(--danger);
}

/* ============================================
   Forms
   ============================================ */

.form-group {
    margin-bottom: 20px;
}

.form-label {
    display: block;
    font-size: 14px;
    font-weight: 500;
    color: var(--text-secondary);
    margin-bottom: 8px;
}

.form-input {
    width: 100%;
    padding: 12px 16px;
    background: var(--bg-dark);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    color: var(--text-primary);
    font-size: 14px;
    transition: border-color 0.2s;
}

.form-input:focus {
    outline: none;
    border-color: var(--primary);
}

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

textarea.form-input {
    resize: vertical;
    min-height: 120px;
    font-family: monospace;
}

/* ============================================
   Buttons
   ============================================ */

.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    padding: 12px 24px;
    border-radius: var(--radius);
    font-size: 14px;
    font-weight: 500;
    cursor: pointer;
    transition: all 0.2s;
    border: none;
    text-decoration: none;
}

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

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

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

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

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

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

.btn-sm {
    padding: 8px 16px;
    font-size: 12px;
}

.btn:disabled {
    opacity: 0.5;
    cursor: not-allowed;
}

/* ============================================
   Tables
   ============================================ */

.table-container {
    overflow-x: auto;
}

table {
    width: 100%;
    border-collapse: collapse;
}

th, td {
    padding: 12px 16px;
    text-align: left;
    border-bottom: 1px solid var(--border);
}

th {
    font-size: 12px;
    font-weight: 600;
    text-transform: uppercase;
    color: var(--text-secondary);
    letter-spacing: 0.5px;
}

td {
    font-size: 14px;
}

tr:hover {
    background: var(--bg-hover);
}

/* ============================================
   Alerts
   ============================================ */

.alert {
    padding: 16px 20px;
    border-radius: var(--radius);
    margin-bottom: 20px;
    display: flex;
    align-items: center;
    gap: 12px;
}

.alert-success {
    background: rgba(34, 197, 94, 0.1);
    border: 1px solid var(--success);
    color: var(--success);
}

.alert-error {
    background: rgba(239, 68, 68, 0.1);
    border: 1px solid var(--danger);
    color: var(--danger);
}

.alert-warning {
    background: rgba(245, 158, 11, 0.1);
    border: 1px solid var(--warning);
    color: var(--warning);
}

/* ============================================
   Short URL Display
   ============================================ */

.short-url-display {
    display: flex;
    align-items: center;
    gap: 12px;
    background: var(--bg-dark);
    padding: 16px;
    border-radius: var(--radius);
    margin: 20px 0;
}

.short-url-display a {
    color: var(--primary);
    font-size: 18px;
    font-weight: 500;
    text-decoration: none;
}

.short-url-display a:hover {
    text-decoration: underline;
}

.copy-btn {
    padding: 8px 12px;
    background: var(--bg-hover);
    border: none;
    border-radius: var(--radius);
    color: var(--text-primary);
    cursor: pointer;
    font-size: 14px;
}

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

/* ============================================
   Loading
   ============================================ */

.loading {
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 40px;
}

.spinner {
    width: 40px;
    height: 40px;
    border: 3px solid var(--border);
    border-top-color: var(--primary);
    border-radius: 50%;
    animation: spin 1s linear infinite;
}

@keyframes spin {
    to { transform: rotate(360deg); }
}

/* ============================================
   Page Headers
   ============================================ */

.page-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 32px;
}

.page-title {
    font-size: 28px;
    font-weight: 700;
}

.page-subtitle {
    color: var(--text-secondary);
    margin-top: 4px;
}

/* ============================================
   URL Truncation
   ============================================ */

.url-truncate {
    max-width: 300px;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
}

/* ============================================
   Empty State
   ============================================ */

.empty-state {
    text-align: center;
    padding: 60px 20px;
    color: var(--text-secondary);
}

.empty-state-icon {
    font-size: 48px;
    margin-bottom: 16px;
}

.empty-state-title {
    font-size: 18px;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 8px;
}

/* ============================================
   Responsive
   ============================================ */

@media (max-width: 768px) {
    .sidebar {
        width: 100%;
        height: auto;
        position: relative;
    }
    
    .main-content {
        margin-left: 0;
        padding: 16px;
    }
    
    .app-container {
        flex-direction: column;
    }
    
    .stats-grid {
        grid-template-columns: 1fr;
    }
}