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

:root {
    --primary-color: #4f46e5;
    --secondary-color: #6b7280;
    --success-color: #10b981;
    --danger-color: #ef4444;
    --warning-color: #f59e0b;
    --info-color: #3b82f6;
    --bg-color: #f9fafb;
    --card-bg: #ffffff;
    --text-color: #1f2937;
    --border-color: #e5e7eb;
    --shadow: 0 1px 3px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 10px 25px rgba(0, 0, 0, 0.1);
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: var(--text-color);
    min-height: 100vh;
    line-height: 1.6;
}

/* Login Page Styles */
.login-container {
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
    padding: 20px;
}

.login-box {
    background: var(--card-bg);
    padding: 40px;
    border-radius: 16px;
    box-shadow: var(--shadow-lg);
    max-width: 450px;
    width: 100%;
    animation: fadeInUp 0.5s ease;
}

.login-box h1 {
    color: var(--primary-color);
    margin-bottom: 10px;
    font-size: 2rem;
    text-align: center;
}

.subtitle {
    text-align: center;
    color: var(--secondary-color);
    margin-bottom: 30px;
    font-size: 0.95rem;
}

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

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

.form-group input {
    width: 100%;
    padding: 12px 16px;
    border: 2px solid var(--border-color);
    border-radius: 8px;
    font-size: 1rem;
    transition: all 0.3s ease;
}

.form-group input:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(79, 70, 229, 0.1);
}

.error-message {
    background: #fee2e2;
    color: var(--danger-color);
    padding: 12px;
    border-radius: 8px;
    margin-bottom: 20px;
    display: none;
    border-left: 4px solid var(--danger-color);
}

.login-info {
    margin-top: 30px;
    padding-top: 20px;
    border-top: 1px solid var(--border-color);
    font-size: 0.9rem;
    color: var(--secondary-color);
}

.login-info code {
    background: var(--bg-color);
    padding: 2px 8px;
    border-radius: 4px;
    color: var(--primary-color);
    font-weight: 600;
}

/* Home Page Styles */
.container {
    max-width: 1400px;
    margin: 0 auto;
    padding: 20px;
}

.header {
    background: var(--card-bg);
    padding: 25px 30px;
    border-radius: 12px;
    box-shadow: var(--shadow);
    margin-bottom: 30px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: 15px;
}

.header h1 {
    color: var(--primary-color);
    font-size: 1.8rem;
}

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

.user-info span {
    color: var(--secondary-color);
}

/* Upload Section */
.upload-section {
    background: var(--card-bg);
    padding: 30px;
    border-radius: 12px;
    box-shadow: var(--shadow);
    margin-bottom: 30px;
}

.upload-section h2 {
    color: var(--text-color);
    margin-bottom: 20px;
    font-size: 1.5rem;
}

.upload-area {
    border: 3px dashed var(--border-color);
    border-radius: 12px;
    padding: 50px 20px;
    text-align: center;
    transition: all 0.3s ease;
    cursor: pointer;
    background: var(--bg-color);
}

.upload-area:hover,
.upload-area.dragover {
    border-color: var(--primary-color);
    background: rgba(79, 70, 229, 0.05);
}

.upload-icon {
    font-size: 3rem;
    margin-bottom: 15px;
}

.upload-text {
    font-size: 1.1rem;
    color: var(--text-color);
    margin-bottom: 8px;
}

.upload-hint {
    color: var(--secondary-color);
    font-size: 0.9rem;
    margin-bottom: 20px;
}

.file-list {
    margin-top: 20px;
}

.file-item {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 12px 16px;
    background: var(--bg-color);
    border-radius: 8px;
    margin-bottom: 10px;
    border: 1px solid var(--border-color);
}

.file-item-info {
    display: flex;
    align-items: center;
    gap: 10px;
    flex: 1;
}

.file-item-name {
    font-weight: 500;
    color: var(--text-color);
}

.file-item-size {
    color: var(--secondary-color);
    font-size: 0.9rem;
}

.file-item-remove {
    background: var(--danger-color);
    color: white;
    border: none;
    padding: 6px 12px;
    border-radius: 6px;
    cursor: pointer;
    font-size: 0.9rem;
    transition: all 0.3s ease;
}

.file-item-remove:hover {
    background: #dc2626;
}

/* Table Section */
.table-section {
    background: var(--card-bg);
    padding: 30px;
    border-radius: 12px;
    box-shadow: var(--shadow);
}

.table-section h2 {
    color: var(--text-color);
    margin-bottom: 20px;
    font-size: 1.5rem;
}

.message {
    padding: 12px 16px;
    border-radius: 8px;
    margin-bottom: 20px;
    display: none;
}

.message.success {
    background: #d1fae5;
    color: var(--success-color);
    border-left: 4px solid var(--success-color);
    display: block;
}

.message.error {
    background: #fee2e2;
    color: var(--danger-color);
    border-left: 4px solid var(--danger-color);
    display: block;
}

.table-responsive {
    overflow-x: auto;
}

.file-table {
    width: 100%;
    border-collapse: collapse;
    font-size: 0.95rem;
}

.file-table thead {
    background: var(--bg-color);
}

.file-table th {
    padding: 14px 12px;
    text-align: left;
    font-weight: 600;
    color: var(--text-color);
    border-bottom: 2px solid var(--border-color);
    white-space: nowrap;
}

.file-table td {
    padding: 12px;
    border-bottom: 1px solid var(--border-color);
    vertical-align: middle;
}

.file-table tbody tr {
    transition: all 0.2s ease;
}

.file-table tbody tr:hover {
    background: var(--bg-color);
}

.hash {
    font-family: 'Courier New', monospace;
    font-size: 0.85rem;
    background: var(--bg-color);
    padding: 4px 8px;
    border-radius: 4px;
    color: var(--primary-color);
}

.action-buttons {
    display: flex;
    gap: 8px;
    flex-wrap: wrap;
}

/* Buttons */
.btn {
    padding: 10px 20px;
    border: none;
    border-radius: 8px;
    font-size: 1rem;
    font-weight: 500;
    cursor: pointer;
    transition: all 0.3s ease;
    text-decoration: none;
    display: inline-block;
    text-align: center;
}

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

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

.btn-primary:hover:not(:disabled) {
    background: #4338ca;
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(79, 70, 229, 0.4);
}

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

.btn-secondary:hover {
    background: #4b5563;
}

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

.btn-success:hover:not(:disabled) {
    background: #059669;
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(16, 185, 129, 0.4);
}

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

.btn-danger:hover {
    background: #dc2626;
}

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

.btn-warning:hover {
    background: #d97706;
}

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

.btn-info:hover {
    background: #2563eb;
}

.btn-sm {
    padding: 6px 12px;
    font-size: 0.9rem;
}

/* Animations */
@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

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

.loading {
    display: inline-block;
    width: 16px;
    height: 16px;
    border: 2px solid rgba(255, 255, 255, 0.3);
    border-top-color: white;
    border-radius: 50%;
    animation: spin 0.6s linear infinite;
}

/* Responsive */
@media (max-width: 768px) {
    .header {
        text-align: center;
    }
    
    .header h1 {
        font-size: 1.5rem;
    }
    
    .user-info {
        flex-direction: column;
        width: 100%;
    }
    
    .table-responsive {
        font-size: 0.85rem;
    }
    
    .file-table th,
    .file-table td {
        padding: 8px 6px;
    }
    
    .action-buttons {
        flex-direction: column;
    }
    
    .upload-section,
    .table-section {
        padding: 20px;
    }
}