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

:root {
    --primary: #4A6FA5;
    --secondary: #D5E3F0;
    --accent: #F2C14E;
    --background: #F8FAFD;
    --text: #1B1B1B;
    --white: #FFFFFF;
    --gray: #6c757d;
    --light-gray: #e9ecef;
    --success: #28a745;
    --danger: #dc3545;
    --warning: #ffc107;
    --info: #17a2b8;
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background-color: var(--background);
    color: var(--text);
    line-height: 1.6;
}

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

/* Sidebar */
.sidebar {
    width: 250px;
    background: var(--primary);
    color: var(--white);
    transition: all 0.3s ease;
    position: fixed;
    height: 100vh;
    overflow-y: auto;
    z-index: 1000;
}

.sidebar-header {
    padding: 20px;
    text-align: center;
    border-bottom: 1px solid rgba(255,255,255,0.1);
}

.sidebar-header h2 {
    color: var(--accent);
    font-size: 1.5rem;
}

.sidebar-menu {
    list-style: none;
    padding: 0;
    margin: 20px 0;
}

.sidebar-menu li {
    margin: 5px 0;
}

.sidebar-menu a {
    display: flex;
    align-items: center;
    padding: 12px 20px;
    color: var(--white);
    text-decoration: none;
    transition: all 0.3s ease;
    border-left: 3px solid transparent;
}

.sidebar-menu a:hover {
    background: rgba(255,255,255,0.1);
    border-left-color: var(--accent);
    padding-left: 25px;
}

.sidebar-menu a.active {
    background: rgba(255,255,255,0.15);
    border-left-color: var(--accent);
}

.sidebar-menu i {
    margin-right: 10px;
    width: 20px;
    text-align: center;
}

/* Main Content */
.main-content {
    flex: 1;
    margin-left: 250px;
    transition: all 0.3s ease;
}

/* Header */
.header {
    background: var(--white);
    padding: 15px 30px;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.user-info {
    display: flex;
    align-items: center;
    gap: 15px;
}

.user-info span {
    font-weight: 500;
}

/* Content Area */
.content {
    padding: 30px;
}

/* Cards */
.card {
    background: var(--white);
    border-radius: 10px;
    box-shadow: 0 5px 15px rgba(0,0,0,0.08);
    margin-bottom: 20px;
    transition: all 0.3s ease;
    border: none;
}

.card:hover {
    transform: translateY(-5px);
    box-shadow: 0 8px 25px rgba(0,0,0,0.15);
}

.card-header {
    background: var(--white);
    border-bottom: 1px solid var(--light-gray);
    padding: 20px;
    font-weight: 600;
    color: var(--primary);
}

.card-body {
    padding: 20px;
}

/* Buttons */
.btn {
    padding: 10px 20px;
    border: none;
    border-radius: 6px;
    cursor: pointer;
    text-decoration: none;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    transition: all 0.3s ease;
    font-weight: 500;
    position: relative;
    overflow: hidden;
}

.btn:after {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    width: 5px;
    height: 5px;
    background: rgba(255, 255, 255, 0.5);
    opacity: 0;
    border-radius: 100%;
    transform: scale(1, 1) translate(-50%);
    transform-origin: 50% 50%;
}

.btn:focus:not(:active)::after {
    animation: ripple 1s ease-out;
}

@keyframes ripple {
    0% {
        transform: scale(0, 0);
        opacity: 0.5;
    }
    100% {
        transform: scale(20, 20);
        opacity: 0;
    }
}

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

.btn-primary:hover {
    background: #3a5a85;
    transform: translateY(-2px);
}

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

.btn-warning {
    background: var(--warning);
    color: var(--text);
}

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

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

.btn-sm {
    padding: 6px 12px;
    font-size: 0.875rem;
}

/* Tables */
.table {
    width: 100%;
    background: var(--white);
    border-radius: 10px;
    overflow: hidden;
    box-shadow: 0 5px 15px rgba(0,0,0,0.08);
}

.table th {
    background: var(--primary);
    color: var(--white);
    padding: 15px;
    font-weight: 600;
    text-align: left;
}

.table td {
    padding: 15px;
    border-bottom: 1px solid var(--light-gray);
}

.table tr:hover {
    background: var(--secondary);
}

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

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

.form-control {
    width: 100%;
    padding: 12px 15px;
    border: 2px solid var(--light-gray);
    border-radius: 6px;
    font-size: 16px;
    transition: all 0.3s ease;
}

.form-control:focus {
    outline: none;
    border-color: var(--primary);
    box-shadow: 0 0 0 3px rgba(74, 111, 165, 0.1);
}

/* Alerts */
.alert {
    padding: 15px 20px;
    border-radius: 6px;
    margin-bottom: 20px;
    border-left: 4px solid;
}

.alert-success {
    background: #d4edda;
    border-color: var(--success);
    color: #155724;
}

.alert-danger {
    background: #f8d7da;
    border-color: var(--danger);
    color: #721c24;
}

.alert-warning {
    background: #fff3cd;
    border-color: var(--warning);
    color: #856404;
}

/* Dashboard Stats */
.stats-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 20px;
    margin-bottom: 30px;
}

.stat-card {
    background: linear-gradient(135deg, var(--primary), #3a5a85);
    color: var(--white);
    padding: 25px;
    border-radius: 10px;
    text-align: center;
    transition: all 0.3s ease;
}

.stat-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 10px 25px rgba(0,0,0,0.2);
}

.stat-card h3 {
    font-size: 2rem;
    margin-bottom: 10px;
}

.stat-card p {
    opacity: 0.9;
}

/* Book Cover */
.book-cover {
    width: 60px;
    height: 80px;
    object-fit: cover;
    border-radius: 4px;
    box-shadow: 0 2px 5px rgba(0,0,0,0.2);
}

/* Login Page */
.login-container {
    min-height: 100vh;
    display: flex;
    align-items: center;
}

.login-card {
    background: var(--white);
    padding: 40px;
    border-radius: 15px;
    box-shadow: 0 20px 40px rgba(0,0,0,0.1);
    width: 100%;
    max-width: 400px;
    animation: slideUp 0.5s ease;
}

@keyframes slideUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.login-header {
    text-align: center;
    margin-bottom: 30px;
}

.login-header h2 {
    color: var(--primary);
    margin-bottom: 10px;
}


/* Responsive */
@media (max-width: 768px) {
    .sidebar {
        width: 70px;
    }
    
    .sidebar-header h2,
    .sidebar-menu span {
        display: none;
    }
    
    .sidebar-menu a {
        justify-content: center;
        padding: 15px;
    }
    
    .sidebar-menu i {
        margin-right: 0;
        font-size: 1.2rem;
    }
    
    .main-content {
        margin-left: 70px;
    }
    
    .stats-grid {
        grid-template-columns: 1fr;
    }
}

/* Animation classes */
.fade-in {
    animation: fadeIn 0.5s ease;
}

@keyframes fadeIn {
    from { opacity: 0; }
    to { opacity: 1; }
}

.slide-in-left {
    animation: slideInLeft 0.5s ease;
}

@keyframes slideInLeft {
    from {
        opacity: 0;
        transform: translateX(-30px);
    }
    to {
        opacity: 1;
        transform: translateX(0);
    }
}