@import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700;800&display=swap');

:root {
    --bg-primary: #0f172a;
    --bg-surface: #1e293b;
    --bg-surface-light: #ffffff;
    --bg-card: rgba(30, 41, 59, 0.7);
    --border-color: rgba(255, 255, 255, 0.1);
    --border-light: #e2e8f0;
    --text-primary: #f8fafc;
    --text-secondary: #94a3b8;
    --text-dark: #0f172a;
    --text-muted: #64748b;
    --accent-primary: #6366f1;
    --accent-hover: #4f46e5;
    --accent-gradient: linear-gradient(135deg, #6366f1 0%, #a855f7 100%);
    --success: #10b981;
    --warning: #f59e0b;
    --danger: #ef4444;
    --info: #06b6d4;
    --radius-sm: 6px;
    --radius-md: 12px;
    --radius-lg: 18px;
    --shadow-glass: 0 8px 32px 0 rgba(0, 0, 0, 0.37);
    --shadow-soft: 0 4px 20px rgba(0, 0, 0, 0.08);
}

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

body {
    font-family: 'Inter', system-ui, -apple-system, sans-serif;
    background-color: var(--bg-primary);
    color: var(--text-primary);
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
}

body.light-theme {
    background-color: #f1f5f9;
    color: var(--text-dark);
}

.container {
    width: 100%;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 24px;
}

/* Glassmorphism Card */
.glass-card {
    background: rgba(30, 41, 59, 0.75);
    backdrop-filter: blur(16px);
    -webkit-backdrop-filter: blur(16px);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-glass);
    padding: 32px;
    transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.light-theme .glass-card {
    background: #ffffff;
    border: 1px solid var(--border-light);
    box-shadow: var(--shadow-soft);
}

/* Navbar */
.navbar {
    background: rgba(15, 23, 42, 0.85);
    backdrop-filter: blur(12px);
    border-bottom: 1px solid var(--border-color);
    padding: 16px 0;
    position: sticky;
    top: 0;
    z-index: 100;
}

.light-theme .navbar {
    background: #ffffff;
    border-bottom: 1px solid var(--border-light);
}

.navbar-inner {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.brand {
    font-size: 20px;
    font-weight: 800;
    background: var(--accent-gradient);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    text-decoration: none;
    display: flex;
    align-items: center;
    gap: 10px;
}

.nav-links {
    display: flex;
    align-items: center;
    gap: 20px;
    list-style: none;
}

.nav-links a {
    color: var(--text-secondary);
    text-decoration: none;
    font-weight: 500;
    font-size: 14px;
    transition: color 0.2s;
}

.light-theme .nav-links a {
    color: var(--text-muted);
}

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

/* Buttons */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    padding: 10px 20px;
    font-weight: 600;
    font-size: 14px;
    border-radius: var(--radius-sm);
    border: none;
    cursor: pointer;
    text-decoration: none;
    transition: all 0.2s cubic-bezier(0.4, 0, 0.2, 1);
}

.btn-primary {
    background: var(--accent-gradient);
    color: #ffffff;
    box-shadow: 0 4px 14px rgba(99, 102, 241, 0.35);
}

.btn-primary:hover {
    transform: translateY(-1px);
    box-shadow: 0 6px 20px rgba(99, 102, 241, 0.5);
}

.btn-secondary {
    background: rgba(255, 255, 255, 0.08);
    color: var(--text-primary);
    border: 1px solid var(--border-color);
}

.light-theme .btn-secondary {
    background: #f1f5f9;
    color: var(--text-dark);
    border: 1px solid var(--border-light);
}

.btn-secondary:hover {
    background: rgba(255, 255, 255, 0.15);
}

.btn-sm {
    padding: 6px 12px;
    font-size: 12px;
    border-radius: var(--radius-sm);
}

.btn-danger {
    background: #ef4444;
    color: #ffffff;
}

/* Status Badges */
.badge {
    display: inline-flex;
    align-items: center;
    padding: 4px 10px;
    border-radius: 9999px;
    font-size: 12px;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.badge-pending { background: rgba(245, 158, 11, 0.15); color: #fbbf24; border: 1px solid rgba(245, 158, 11, 0.3); }
.badge-sent { background: rgba(99, 102, 241, 0.15); color: #818cf8; border: 1px solid rgba(99, 102, 241, 0.3); }
.badge-opened { background: rgba(6, 182, 212, 0.15); color: #22d3ee; border: 1px solid rgba(6, 182, 212, 0.3); }
.badge-submitted, .badge-approved { background: rgba(16, 185, 129, 0.15); color: #34d399; border: 1px solid rgba(16, 185, 129, 0.3); }
.badge-rejected { background: rgba(239, 68, 68, 0.15); color: #f87171; border: 1px solid rgba(239, 68, 68, 0.3); }
.badge-expired { background: rgba(148, 163, 184, 0.15); color: #94a3b8; border: 1px solid rgba(148, 163, 184, 0.3); }

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

.form-group label {
    display: block;
    font-size: 13px;
    font-weight: 600;
    margin-bottom: 8px;
    color: var(--text-secondary);
}

.light-theme .form-group label {
    color: var(--text-muted);
}

.form-control {
    width: 100%;
    padding: 12px 16px;
    background: rgba(15, 23, 42, 0.6);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-sm);
    color: var(--text-primary);
    font-size: 14px;
    font-family: inherit;
    transition: border-color 0.2s, box-shadow 0.2s;
}

.light-theme .form-control {
    background: #ffffff;
    border: 1px solid var(--border-light);
    color: var(--text-dark);
}

.form-control:focus {
    outline: none;
    border-color: var(--accent-primary);
    box-shadow: 0 0 0 3px rgba(99, 102, 241, 0.25);
}

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

.table {
    width: 100%;
    border-collapse: separate;
    border-spacing: 0;
    margin-top: 16px;
}

.table th, .table td {
    padding: 14px 18px;
    text-align: left;
    border-bottom: 1px solid var(--border-color);
    font-size: 14px;
}

.light-theme .table th, .light-theme .table td {
    border-bottom: 1px solid var(--border-light);
}

.table th {
    background: rgba(15, 23, 42, 0.4);
    color: var(--text-secondary);
    font-weight: 600;
    font-size: 12px;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.light-theme .table th {
    background: #f8fafc;
    color: var(--text-muted);
}

.table tbody tr {
    transition: background 0.15s;
}

.table tbody tr:hover {
    background: rgba(255, 255, 255, 0.03);
}

.light-theme .table tbody tr:hover {
    background: #f8fafc;
}

/* Canvas Signature Box */
.signature-wrapper {
    position: relative;
    border: 2px dashed rgba(99, 102, 241, 0.4);
    border-radius: var(--radius-md);
    background: rgba(15, 23, 42, 0.8);
    padding: 12px;
    text-align: center;
}

.light-theme .signature-wrapper {
    background: #ffffff;
    border-color: #cbd5e1;
}

canvas#signature-pad {
    width: 100%;
    max-width: 500px;
    height: 180px;
    background: #ffffff;
    border-radius: var(--radius-sm);
    cursor: crosshair;
    touch-action: none;
    box-shadow: inset 0 2px 4px rgba(0, 0, 0, 0.05);
}

.signature-actions {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-top: 10px;
}

/* Alerts */
.alert {
    padding: 14px 18px;
    border-radius: var(--radius-sm);
    margin-bottom: 20px;
    font-size: 14px;
    display: flex;
    align-items: center;
    gap: 12px;
}

.alert-success { background: rgba(16, 185, 129, 0.15); border: 1px solid rgba(16, 185, 129, 0.3); color: #34d399; }
.alert-danger { background: rgba(239, 68, 68, 0.15); border: 1px solid rgba(239, 68, 68, 0.3); color: #f87171; }
.alert-info { background: rgba(6, 182, 212, 0.15); border: 1px solid rgba(6, 182, 212, 0.3); color: #22d3ee; }

/* Grid Dashboard Stats */
.grid-stats {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
    gap: 20px;
    margin-bottom: 30px;
}

.stat-card {
    background: rgba(30, 41, 59, 0.8);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    padding: 20px;
    display: flex;
    flex-direction: column;
}

.stat-value {
    font-size: 28px;
    font-weight: 800;
    color: var(--text-primary);
    margin-top: 4px;
}

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

/* Modal */
.modal {
    display: none;
    position: fixed;
    top: 0; left: 0; width: 100%; height: 100%;
    background: rgba(0, 0, 0, 0.7);
    backdrop-filter: blur(4px);
    z-index: 1000;
    align-items: center;
    justify-content: center;
}

.modal.active {
    display: flex;
}

.modal-content {
    background: #1e293b;
    border: 1px solid var(--border-color);
    border-radius: var(--radius-lg);
    width: 100%;
    max-width: 540px;
    padding: 28px;
    box-shadow: var(--shadow-glass);
}

/* Responsive Form Grids */
.form-grid-4 {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 16px;
}

.form-grid-3 {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 16px;
}

.form-grid-2 {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 16px;
}

@media (max-width: 992px) {
    .form-grid-4 {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media (max-width: 768px) {
    .form-grid-4, .form-grid-3, .form-grid-2 {
        grid-template-columns: 1fr;
    }
    .glass-card {
        padding: 20px 16px;
    }
}