/* ============================================
   DHLTU JOURNAL - Modern Light Style System
   ============================================ */

:root {
    --primary-900: #0c4a6e;
    --primary-800: #075985;
    --primary-700: #0369a1;
    --primary-600: #0284c7;
    --primary-500: #0ea5e9;
    --primary-400: #38bdf8;
    --primary-300: #7dd3fc;
    --primary-200: #bae6fd;
    --primary-100: #e0f2fe;
    --primary-50: #f0f9ff;
    
    --secondary-600: #0d9488;
    --secondary-500: #14b8a6;
    --secondary-400: #2dd4bf;
    --secondary-100: #ccfbf1;
    
    --accent-500: #f59e0b;
    --accent-400: #fbbf24;
    --accent-100: #fef3c7;
    
    --success-500: #22c55e;
    --success-100: #dcfce7;
    --success-700: #15803d;
    
    --danger-500: #ef4444;
    --danger-100: #fee2e2;
    --danger-700: #b91c1c;
    
    --warning-500: #f97316;
    --warning-100: #ffedd5;
    --warning-700: #c2410c;
    
    --info-500: #0ea5e9;
    --info-100: #e0f2fe;
    --info-700: #0369a1;
    
    --neutral-900: #0f172a;
    --neutral-800: #1e293b;
    --neutral-700: #334155;
    --neutral-600: #475569;
    --neutral-500: #64748b;
    --neutral-400: #94a3b8;
    --neutral-300: #cbd5e1;
    --neutral-200: #e2e8f0;
    --neutral-100: #f1f5f9;
    --neutral-50: #f8fafc;
    
    --gradient-primary: linear-gradient(135deg, #0369a1 0%, #0ea5e9 50%, #38bdf8 100%);
    --gradient-hero: linear-gradient(135deg, #e0f2fe 0%, #f0f9ff 30%, #ffffff 70%, #f0f9ff 100%);
    
    --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.08);
    --shadow: 0 4px 6px rgba(0, 0, 0, 0.05);
    --shadow-md: 0 10px 15px rgba(0, 0, 0, 0.08);
    --shadow-lg: 0 20px 25px rgba(0, 0, 0, 0.08);
    --shadow-xl: 0 25px 50px rgba(0, 0, 0, 0.1);
    
    --radius: 0.5rem;
    --radius-lg: 1rem;
    --radius-xl: 1.5rem;
    --radius-full: 9999px;
    
    --transition: 250ms cubic-bezier(0.4, 0, 0.2, 1);
    
    --font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
}

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

html { scroll-behavior: smooth; }

body {
    font-family: var(--font-family);
    font-size: 1rem;
    color: var(--neutral-700);
    background: #f8fafc;
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
}

h1, h2, h3, h4, h5, h6 {
    font-weight: 700;
    line-height: 1.3;
    color: var(--neutral-800);
    margin-bottom: 1rem;
}

h1 { font-size: 3rem; }
h2 { font-size: 2.25rem; }
h3 { font-size: 1.875rem; }
h4 { font-size: 1.5rem; }
h5 { font-size: 1.25rem; }
h6 { font-size: 1.125rem; }

p { margin-bottom: 1rem; color: var(--neutral-600); line-height: 1.7; }

a { color: var(--primary-600); text-decoration: none; transition: color var(--transition); }
a:hover { color: var(--primary-700); }

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 1rem;
}

/* Navbar */
.navbar {
    background: white !important;
    padding: 0.5rem 0;
    box-shadow: 0 1px 3px rgba(0,0,0,0.08);
    position: sticky;
    top: 0;
    z-index: 1030;
}

.navbar .nav-link {
    color: var(--neutral-600) !important;
    font-weight: 500;
    padding: 0.5rem 1rem !important;
    border-radius: var(--radius);
    transition: all var(--transition);
    font-size: 0.9rem;
}

.navbar .nav-link:hover,
.navbar .nav-link.active {
    background: var(--primary-50);
    color: var(--primary-600) !important;
}

/* Buttons */
.btn {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.625rem 1.5rem;
    font-weight: 600;
    border-radius: var(--radius);
    transition: all var(--transition);
    font-size: 0.9rem;
    cursor: pointer;
    border: 2px solid transparent;
    text-decoration: none;
}

.btn:hover { transform: translateY(-1px); box-shadow: var(--shadow); }

.btn-primary {
    background: var(--gradient-primary);
    color: white !important;
    border: none;
}

.btn-primary:hover { box-shadow: var(--shadow-md); }

.btn-outline-primary {
    background: transparent;
    border: 2px solid var(--primary-500);
    color: var(--primary-600) !important;
}

.btn-outline-primary:hover {
    background: var(--primary-500);
    color: white !important;
}

.btn-lg { padding: 0.75rem 2rem; font-size: 1rem; }
.btn-sm { padding: 0.4rem 1rem; font-size: 0.8rem; }

/* Cards */
.card {
    background: white;
    border: 1px solid var(--neutral-200);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-sm);
    overflow: hidden;
}

.card-header {
    background: white;
    border-bottom: 1px solid var(--neutral-100);
    padding: 1.25rem 1.5rem;
    font-weight: 600;
}

.card-body { padding: 1.5rem; }

/* Forms */
.form-label {
    display: block;
    font-weight: 600;
    color: var(--neutral-700);
    margin-bottom: 0.5rem;
    font-size: 0.875rem;
}

.form-control, .form-select {
    width: 100%;
    padding: 0.625rem 1rem;
    border: 2px solid var(--neutral-200);
    border-radius: var(--radius);
    font-size: 0.95rem;
    color: var(--neutral-700);
    background: white;
    transition: all var(--transition);
    font-family: var(--font-family);
}

.form-control:focus, .form-select:focus {
    outline: none;
    border-color: var(--primary-400);
    box-shadow: 0 0 0 3px rgba(14, 165, 233, 0.2);
}

/* Tables */
.table { width: 100%; border-collapse: separate; border-spacing: 0; }
.table thead th {
    background: var(--neutral-50);
    color: var(--neutral-600);
    font-weight: 600;
    font-size: 0.8rem;
    text-transform: uppercase;
    letter-spacing: 0.5px;
    padding: 1rem;
    border-bottom: 2px solid var(--neutral-200);
}
.table tbody td {
    padding: 1rem;
    border-bottom: 1px solid var(--neutral-100);
    font-size: 0.9rem;
}
.table tbody tr:hover { background: var(--primary-50); }

/* Badges */
.badge {
    display: inline-flex;
    align-items: center;
    gap: 0.25rem;
    padding: 0.3rem 0.75rem;
    border-radius: var(--radius-full);
    font-weight: 600;
    font-size: 0.75rem;
    letter-spacing: 0.3px;
}

.badge-primary { background: var(--primary-100); color: var(--primary-700); }
.badge-success { background: var(--success-100); color: var(--success-700); }
.badge-danger { background: var(--danger-100); color: var(--danger-700); }
.badge-warning { background: var(--warning-100); color: var(--warning-700); }

/* Alerts */
.alert {
    border: none;
    border-radius: var(--radius);
    padding: 1rem 1.25rem;
    margin-bottom: 1.5rem;
    font-size: 0.9rem;
}

.alert-success { background: var(--success-100); color: var(--success-700); border-left: 4px solid var(--success-500); }
.alert-danger { background: var(--danger-100); color: var(--danger-700); border-left: 4px solid var(--danger-500); }
.alert-warning { background: var(--warning-100); color: var(--warning-700); border-left: 4px solid var(--warning-500); }
.alert-info { background: var(--info-100); color: var(--info-700); border-left: 4px solid var(--info-500); }

/* Dashboard Layout */
.dashboard-container { display: flex; min-height: 100vh; }

.sidebar {
    width: 260px;
    background: white;
    border-right: 1px solid var(--neutral-200);
    position: fixed;
    top: 0;
    left: 0;
    height: 100vh;
    overflow-y: auto;
    z-index: 1020;
}

.main-content {
    margin-left: 260px;
    flex: 1;
    padding: 2rem;
    background: var(--neutral-50);
    min-height: 100vh;
}

/* Utility Classes */
.text-muted { color: var(--neutral-500) !important; }
.text-primary { color: var(--primary-600) !important; }
.text-success { color: var(--success-500) !important; }
.text-danger { color: var(--danger-500) !important; }

.text-center { text-align: center; }
.text-start { text-align: left; }
.text-end { text-align: right; }

.fw-bold { font-weight: 700; }
.fw-semibold { font-weight: 600; }
.fw-medium { font-weight: 500; }

.d-flex { display: flex; }
.d-block { display: block; }
.d-none { display: none; }
.justify-content-center { justify-content: center; }
.justify-content-between { justify-content: space-between; }
.align-items-center { align-items: center; }
.flex-wrap { flex-wrap: wrap; }
.gap-1 { gap: 0.5rem; }
.gap-2 { gap: 1rem; }
.gap-3 { gap: 1.5rem; }

.mt-1 { margin-top: 0.5rem; }
.mt-2 { margin-top: 1rem; }
.mt-3 { margin-top: 1.5rem; }
.mt-4 { margin-top: 2rem; }
.mt-5 { margin-top: 3rem; }
.mb-0 { margin-bottom: 0 !important; }
.mb-1 { margin-bottom: 0.5rem; }
.mb-2 { margin-bottom: 1rem; }
.mb-3 { margin-bottom: 1.5rem; }
.mb-4 { margin-bottom: 2rem; }
.mb-5 { margin-bottom: 3rem; }
.me-1 { margin-right: 0.5rem; }
.me-2 { margin-right: 1rem; }
.ms-1 { margin-left: 0.5rem; }
.ms-2 { margin-left: 1rem; }
.ms-auto { margin-left: auto; }

.p-3 { padding: 1.5rem; }
.p-4 { padding: 2rem; }
.p-5 { padding: 3rem; }
.py-5 { padding-top: 3rem; padding-bottom: 3rem; }

.w-100 { width: 100%; }
.h-100 { height: 100%; }

.bg-white { background: white; }
.bg-light { background: var(--neutral-50); }

.rounded { border-radius: var(--radius); }
.rounded-3 { border-radius: var(--radius); }
.rounded-4 { border-radius: var(--radius-lg); }
.rounded-circle { border-radius: 50%; }
.rounded-pill { border-radius: var(--radius-full); }

.shadow-sm { box-shadow: var(--shadow-sm); }
.shadow { box-shadow: var(--shadow); }
.shadow-lg { box-shadow: var(--shadow-lg); }

.border { border: 1px solid var(--neutral-200); }
.border-0 { border: none !important; }

.position-relative { position: relative; }
.position-fixed { position: fixed; }
.overflow-hidden { overflow: hidden; }

.opacity-50 { opacity: 0.5; }
.opacity-75 { opacity: 0.75; }

.small { font-size: 0.875rem; }

.list-unstyled { list-style: none; padding: 0; margin: 0; }

.dropdown-menu {
    background: white;
    border: 1px solid var(--neutral-200);
    border-radius: var(--radius);
    box-shadow: var(--shadow-lg);
    padding: 0.5rem 0;
}

.dropdown-item {
    padding: 0.5rem 1.25rem;
    color: var(--neutral-700);
    font-size: 0.9rem;
    display: flex;
    align-items: center;
    gap: 0.5rem;
    transition: all var(--transition);
}

.dropdown-item:hover {
    background: var(--neutral-50);
    color: var(--neutral-900);
}

.dropdown-divider {
    border-top: 1px solid var(--neutral-200);
    margin: 0.5rem 0;
}

/* Responsive */
@media (max-width: 992px) {
    .sidebar { transform: translateX(-100%); }
    .sidebar.show { transform: translateX(0); }
    .main-content { margin-left: 0; }
}

@media (max-width: 768px) {
    h1 { font-size: 2rem; }
    h2 { font-size: 1.75rem; }
    .container { padding: 0 1rem; }
}

@media (max-width: 576px) {
    .d-sm-none { display: none !important; }
    .d-sm-inline { display: inline !important; }
}