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

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background: linear-gradient(135deg, #1a1a2e 0%, #16213e 100%);
    color: #ffffff;
    min-height: 100vh;
    line-height: 1.6;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 20px;
}

/* Header */
header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 40px;
    padding-bottom: 20px;
    border-bottom: 2px solid #2a2a54;
}

header h1 {
    font-size: 2.5rem;
    font-weight: 700;
    color: #64ffda;
    text-shadow: 0 0 20px rgba(100, 255, 218, 0.3);
}

header h1 i {
    margin-right: 15px;
    color: #ff6b6b;
}

/* Buttons */
.btn {
    padding: 12px 24px;
    border: none;
    border-radius: 8px;
    cursor: pointer;
    font-size: 1rem;
    font-weight: 600;
    transition: all 0.3s ease;
    text-decoration: none;
    display: inline-flex;
    align-items: center;
    gap: 8px;
}

.btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 25px rgba(0, 0, 0, 0.3);
}

.admin-btn {
    background: linear-gradient(45deg, #667eea 0%, #764ba2 100%);
    color: white;
}

.admin-btn:hover {
    background: linear-gradient(45deg, #764ba2 0%, #667eea 100%);
}

.btn-primary {
    background: linear-gradient(45deg, #64ffda 0%, #4ecdc4 100%);
    color: #1a1a2e;
    width: 100%;
}

.btn-primary:hover {
    background: linear-gradient(45deg, #4ecdc4 0%, #64ffda 100%);
}

.btn-upload {
    background: linear-gradient(45deg, #ff6b6b 0%, #ee5a52 100%);
    color: white;
    width: 100%;
    font-size: 1.1rem;
    padding: 15px 30px;
}

.btn-upload:hover {
    background: linear-gradient(45deg, #ee5a52 0%, #ff6b6b 100%);
}

.btn-download {
    background: linear-gradient(45deg, #4ecdc4 0%, #44a08d 100%);
    color: white;
    padding: 10px 20px;
    font-size: 0.9rem;
}

.btn-download:hover {
    background: linear-gradient(45deg, #44a08d 0%, #4ecdc4 100%);
}

.btn-secondary {
    background: linear-gradient(45deg, #6c757d 0%, #495057 100%);
    color: white;
    margin-top: 20px;
}

.btn-secondary:hover {
    background: linear-gradient(45deg, #495057 0%, #6c757d 100%);
}

.btn-delete {
    background: linear-gradient(45deg, #dc3545 0%, #c82333 100%);
    color: white;
    padding: 10px 20px;
    font-size: 0.9rem;
    margin-left: 10px;
}

.btn-delete:hover {
    background: linear-gradient(45deg, #c82333 0%, #dc3545 100%);
}

.file-actions {
    display: flex;
    align-items: center;
    flex-wrap: wrap;
    gap: 10px;
}

/* Modal */
.modal {
    display: none;
    position: fixed;
    z-index: 1000;
    left: 0;
    top: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.8);
    backdrop-filter: blur(5px);
}

.modal-content {
    background: linear-gradient(135deg, #2a2a54 0%, #1a1a2e 100%);
    margin: 10% auto;
    padding: 30px;
    border-radius: 15px;
    width: 90%;
    max-width: 400px;
    box-shadow: 0 20px 60px rgba(0, 0, 0, 0.5);
    border: 1px solid #444;
}

.close {
    color: #aaa;
    float: right;
    font-size: 28px;
    font-weight: bold;
    cursor: pointer;
    transition: color 0.3s ease;
}

.close:hover {
    color: #ff6b6b;
}

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

.form-group label {
    display: block;
    margin-bottom: 8px;
    font-weight: 600;
    color: #64ffda;
}

.form-group input {
    width: 100%;
    padding: 12px;
    border: 2px solid #444;
    border-radius: 8px;
    background: rgba(255, 255, 255, 0.1);
    color: white;
    font-size: 1rem;
    transition: border-color 0.3s ease;
}

.form-group input:focus {
    outline: none;
    border-color: #64ffda;
    box-shadow: 0 0 10px rgba(100, 255, 218, 0.3);
}

.form-group small {
    color: #aaa;
    font-size: 0.85rem;
    margin-top: 5px;
    display: block;
}

/* Admin Panel */
.admin-panel {
    background: linear-gradient(135deg, #2a2a54 0%, #1a1a2e 100%);
    padding: 30px;
    border-radius: 15px;
    margin-bottom: 40px;
    border: 2px solid #444;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.3);
}

.admin-panel h2 {
    color: #64ffda;
    margin-bottom: 25px;
    font-size: 1.8rem;
}

/* Upload Status */
.upload-status {
    margin-top: 20px;
    padding: 15px;
    border-radius: 8px;
    font-weight: 600;
}

.upload-status.success {
    background: rgba(76, 175, 80, 0.2);
    border: 1px solid #4caf50;
    color: #4caf50;
}

.upload-status.error {
    background: rgba(244, 67, 54, 0.2);
    border: 1px solid #f44336;
    color: #f44336;
}

.upload-status.loading {
    background: rgba(255, 193, 7, 0.2);
    border: 1px solid #ffc107;
    color: #ffc107;
}

/* Files List */
.files-list {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(350px, 1fr));
    gap: 25px;
    margin-top: 30px;
}

.file-item {
    background: linear-gradient(135deg, #2a2a54 0%, #1e1e42 100%);
    padding: 25px;
    border-radius: 15px;
    border: 2px solid #444;
    transition: all 0.3s ease;
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.3);
}

.file-item:hover {
    transform: translateY(-5px);
    box-shadow: 0 15px 35px rgba(0, 0, 0, 0.5);
    border-color: #64ffda;
}

.file-header {
    display: flex;
    align-items: center;
    gap: 15px;
    margin-bottom: 15px;
}

.file-icon {
    font-size: 2.5rem;
    width: 60px;
    height: 60px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 12px;
}

.file-icon.pdf {
    background: linear-gradient(45deg, #ff4757, #ff3838);
    color: white;
}

.file-icon.docx {
    background: linear-gradient(45deg, #2e86de, #54a0ff);
    color: white;
}

.file-icon.mp4 {
    background: linear-gradient(45deg, #5f27cd, #8e44ad);
    color: white;
}

.file-icon.pptx {
    background: linear-gradient(45deg, #ff6348, #ff4757);
    color: white;
}

.file-icon.xlsx {
    background: linear-gradient(45deg, #00d2d3, #01a3a4);
    color: white;
}

.file-icon.default {
    background: linear-gradient(45deg, #6c757d, #495057);
    color: white;
}

.file-info h3 {
    color: #ffffff;
    font-size: 1.3rem;
    margin-bottom: 5px;
    word-break: break-word;
}

.file-meta {
    color: #aaa;
    font-size: 0.9rem;
    display: flex;
    gap: 15px;
    margin-bottom: 15px;
}

/* Main Header */
.main-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 30px;
    padding-bottom: 15px;
    border-bottom: 1px solid #444;
}

.main-header h2 {
    color: #64ffda;
    font-size: 1.8rem;
    margin: 0;
}

/* Loading and Empty States */
.loading {
    text-align: center;
    padding: 60px 20px;
    color: #64ffda;
    font-size: 1.2rem;
}

.loading i {
    font-size: 2rem;
    margin-bottom: 15px;
}

.empty-state {
    text-align: center;
    padding: 80px 20px;
    color: #aaa;
}

.empty-state i {
    font-size: 4rem;
    margin-bottom: 20px;
    color: #444;
}

.empty-state h3 {
    margin-bottom: 10px;
    color: #666;
}

/* Responsive Design */
@media (max-width: 768px) {
    .container {
        padding: 15px;
    }
    
    header {
        flex-direction: column;
        gap: 20px;
        text-align: center;
    }
    
    header h1 {
        font-size: 2rem;
    }
    
    .files-list {
        grid-template-columns: 1fr;
        gap: 20px;
    }
    
    .modal-content {
        margin: 20% auto;
        padding: 20px;
    }
    
    .file-meta {
        flex-direction: column;
        gap: 5px;
    }
}

@media (max-width: 480px) {
    header h1 {
        font-size: 1.6rem;
    }
    
    .file-item {
        padding: 20px;
    }
    
    .file-header {
        flex-direction: column;
        text-align: center;
    }
    
    .file-icon {
        font-size: 2rem;
        width: 50px;
        height: 50px;
    }
}