/* Reset & Base Styles */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    min-height: 100vh;
}

.screen {
    width: 100%;
    min-height: 100vh;
}

.hidden {
    display: none !important;
}

/* Login Screen */
.login-container {
    max-width: 400px;
    margin: 100px auto;
    background: white;
    padding: 40px;
    border-radius: 20px;
    box-shadow: 0 20px 60px rgba(0,0,0,0.3);
    text-align: center;
}

.login-container h1 {
    color: #4f46e5;
    margin-bottom: 10px;
    font-size: 2.5em;
}

.subtitle {
    color: #6b7280;
    margin-bottom: 30px;
}

.login-form {
    margin-top: 30px;
}

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

.form-group label {
    display: block;
    margin-bottom: 8px;
    color: #374151;
    font-weight: 600;
}

.form-input, select {
    width: 100%;
    padding: 12px;
    border: 2px solid #e5e7eb;
    border-radius: 10px;
    font-size: 16px;
    transition: all 0.3s;
}

.form-input:focus, select:focus {
    outline: none;
    border-color: #4f46e5;
    box-shadow: 0 0 0 3px rgba(79, 70, 229, 0.1);
}

textarea.form-input {
    min-height: 100px;
    resize: vertical;
}

/* Buttons */
.btn-primary {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    border: none;
    padding: 14px 28px;
    border-radius: 10px;
    font-size: 16px;
    font-weight: 600;
    cursor: pointer;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 10px;
    transition: all 0.3s;
    width: 100%;
}

.btn-primary:hover:not(:disabled) {
    transform: translateY(-2px);
    box-shadow: 0 10px 20px rgba(0,0,0,0.2);
}

.btn-primary:disabled {
    opacity: 0.6;
    cursor: not-allowed;
}

.btn-secondary {
    background: #f3f4f6;
    color: #374151;
    border: 1px solid #d1d5db;
    padding: 10px 20px;
    border-radius: 8px;
    cursor: pointer;
    display: inline-flex;
    align-items: center;
    gap: 8px;
    font-weight: 600;
    transition: all 0.3s;
}

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

.tip {
    margin-top: 20px;
    color: #6b7280;
    font-size: 14px;
    padding: 10px;
    background: #f3f4f6;
    border-radius: 8px;
    line-height: 1.5;
}

/* App Header */
.app-header {
    background: white;
    padding: 15px 30px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
    position: sticky;
    top: 0;
    z-index: 100;
}

.header-left, .header-right {
    display: flex;
    align-items: center;
    gap: 15px;
}

.icon-btn {
    background: none;
    border: none;
    font-size: 20px;
    cursor: pointer;
    color: #4f46e5;
    padding: 8px;
    border-radius: 8px;
    display: none;
}

.icon-btn:hover {
    background: #f3f4f6;
}

.role-badge {
    background: #4f46e5;
    color: white;
    padding: 4px 12px;
    border-radius: 20px;
    font-size: 12px;
    font-weight: 600;
}

/* Sidebar */
.sidebar {
    width: 250px;
    background: white;
    min-height: calc(100vh - 70px);
    border-right: 1px solid #e5e7eb;
    position: fixed;
    left: 0;
    top: 70px;
    transition: transform 0.3s;
}

.sidebar-nav {
    padding: 20px 0;
}

.nav-link {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 15px 25px;
    color: #374151;
    text-decoration: none;
    font-weight: 500;
    transition: all 0.3s;
    border-left: 4px solid transparent;
}

.nav-link:hover {
    background: #f3f4f6;
    color: #4f46e5;
}

.nav-link.active {
    background: #eef2ff;
    color: #4f46e5;
    border-left-color: #4f46e5;
    font-weight: 600;
}

/* Main Content */
.main-content {
    margin-left: 250px;
    padding: 30px;
    min-height: calc(100vh - 70px);
    background: #f9fafb;
}

.view {
    display: none;
    animation: fadeIn 0.5s;
}

.view.active {
    display: block;
}

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(10px); }
    to { opacity: 1; transform: translateY(0); }
}

.view-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 30px;
    flex-wrap: wrap;
    gap: 15px;
}

.view-header h2 {
    color: #374151;
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 24px;
}

/* Stats Grid */
.stats-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 20px;
    margin-bottom: 30px;
}

.stat-card {
    background: white;
    padding: 25px;
    border-radius: 15px;
    box-shadow: 0 5px 15px rgba(0,0,0,0.05);
    text-align: center;
    transition: transform 0.3s;
}

.stat-card:hover {
    transform: translateY(-5px);
}

.stat-card h3 {
    color: #6b7280;
    font-size: 14px;
    margin-bottom: 10px;
    text-transform: uppercase;
    letter-spacing: 1px;
}

.stat-card p {
    color: #4f46e5;
    font-size: 32px;
    font-weight: 700;
}

/* Cards Container */
.cards-container {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: 20px;
}

.card {
    background: white;
    padding: 20px;
    border-radius: 15px;
    box-shadow: 0 5px 15px rgba(0,0,0,0.05);
    border: 1px solid #e5e7eb;
}

.card h4 {
    color: #374151;
    margin-bottom: 10px;
}

.card p {
    color: #6b7280;
    font-size: 14px;
    line-height: 1.5;
}

/* Action Buttons */
.action-buttons {
    display: flex;
    gap: 15px;
    margin-top: 30px;
    flex-wrap: wrap;
}

.action-buttons .btn-primary {
    width: auto;
}

/* Modals */
.modal {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0,0,0,0.5);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 1000;
}

.modal-content {
    background: white;
    padding: 30px;
    border-radius: 15px;
    max-width: 500px;
    width: 90%;
    max-height: 90vh;
    overflow-y: auto;
}

.modal-content h3 {
    margin-bottom: 20px;
    color: #374151;
}

.modal-buttons {
    display: flex;
    gap: 10px;
    justify-content: flex-end;
    margin-top: 20px;
}

/* Loading Overlay */
.loading-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(255,255,255,0.9);
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    z-index: 2000;
}

.loading-spinner {
    width: 50px;
    height: 50px;
    border: 5px solid #e5e7eb;
    border-top-color: #4f46e5;
    border-radius: 50%;
    animation: spin 1s linear infinite;
    margin-bottom: 20px;
}

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

/* Empty State */
.empty-state {
    text-align: center;
    color: #9ca3af;
    padding: 40px;
    grid-column: 1 / -1;
    font-style: italic;
}

.empty-state i {
    font-size: 48px;
    margin-bottom: 15px;
    opacity: 0.5;
}

/* Profile Card */
.profile-card {
    background: white;
    padding: 30px;
    border-radius: 15px;
    max-width: 500px;
    box-shadow: 0 5px 15px rgba(0,0,0,0.05);
}

/* Responsive */
@media (max-width: 768px) {
    .sidebar {
        transform: translateX(-100%);
        z-index: 100;
    }
    
    .sidebar.open {
        transform: translateX(0);
    }
    
    .main-content {
        margin-left: 0;
        padding: 20px;
    }
    
    .app-header {
        padding: 15px 20px;
    }
    
    .stats-grid {
        grid-template-columns: 1fr 1fr;
    }
    
    .cards-container {
        grid-template-columns: 1fr;
    }
    
    .action-buttons {
        flex-direction: column;
    }
}