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

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background: linear-gradient(135deg, #f8fafc 0%, #eff6ff 100%);
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
}

.container {
    width: 100%;
    max-width: 1200px;
    padding: 20px;
    position: relative;
}

/* Auth Forms */
.auth-form {
    background: white;
    padding: 40px;
    border-radius: 15px;
    box-shadow: 0 20px 40px rgba(0, 0, 0, 0.1);
    max-width: 400px;
    margin: 0 auto;
    text-align: center;
}

.auth-form h2 {
    color: #333;
    margin-bottom: 30px;
    font-size: 28px;
}

.auth-form input {
    width: 100%;
    padding: 15px;
    margin-bottom: 15px;
    border: 2px solid #e1e5e9;
    border-radius: 8px;
    font-size: 16px;
    transition: border-color 0.3s ease;
}

.auth-form input:focus {
    outline: none;
    border-color: #0ea5e9;
}

.auth-form button {
    width: 100%;
    padding: 15px;
    background: linear-gradient(135deg, #3b82f6 0%, #06b6d4 100%);
    color: white;
    border: none;
    border-radius: 8px;
    font-size: 16px;
    font-weight: 600;
    cursor: pointer;
    transition: transform 0.2s ease;
}

.auth-form button:hover {
    transform: translateY(-2px);
}

.auth-form p {
    margin-top: 20px;
    color: #666;
}

.auth-form a {
    color: #0ea5e9;
    text-decoration: none;
    font-weight: 600;
}

.auth-form a:hover {
    text-decoration: underline;
}

/* Notes App */
.notes-app {
    background: white;
    border-radius: 15px;
    box-shadow: 0 20px 40px rgba(0, 0, 0, 0.1);
    overflow: hidden;
}

.app-header {
    background: linear-gradient(135deg, #60a5fa 0%, #22d3ee 100%);
    color: #ffffff;
    border-bottom: none;
    padding: 30px;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.app-header h1 {
    font-size: 32px;
    font-weight: 600;
}

.user-info {
    display: flex;
    align-items: center;
    gap: 20px;
}

.logout-btn {
    background: rgba(255, 255, 255, 0.2);
    color: #ffffff;
    border: 1px solid rgba(255, 255, 255, 0.4);
    padding: 10px 20px;
    border-radius: 6px;
    cursor: pointer;
    transition: background 0.3s ease;
}

.logout-btn:hover {
    background: rgba(255, 255, 255, 0.28);
}

/* Add Note Section */
.add-note {
    padding: 30px;
    background: #f8f9fa;
    border-bottom: 1px solid #e9ecef;
}

.add-note input,
.add-note textarea {
    width: 100%;
    padding: 15px;
    margin-bottom: 15px;
    border: 2px solid #e1e5e9;
    border-radius: 8px;
    font-size: 16px;
    font-family: inherit;
    resize: vertical;
}

.add-note input:focus,
.add-note textarea:focus {
    outline: none;
    border-color: #0ea5e9;
}

.add-note textarea {
    min-height: 100px;
}

.add-btn {
    background: linear-gradient(135deg, #3b82f6 0%, #06b6d4 100%);
    color: white;
    border: none;
    padding: 15px 30px;
    border-radius: 8px;
    font-size: 16px;
    font-weight: 600;
    cursor: pointer;
    transition: transform 0.2s ease;
}

.add-btn:hover {
    transform: translateY(-2px);
}

/* Notes Container */
.notes-container {
    padding: 30px;
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: 20px;
}

.note-card {
    background: white;
    border: 1px solid #e9ecef;
    border-radius: 12px;
    padding: 20px;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.05);
    transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.note-card:hover {
    transform: translateY(-4px);
    box-shadow: 0 8px 25px rgba(0, 0, 0, 0.1);
}

.note-card h3 {
    color: #333;
    margin-bottom: 10px;
    font-size: 18px;
    font-weight: 600;
}

.note-card p {
    color: #666;
    line-height: 1.6;
    margin-bottom: 20px;
    word-wrap: break-word;
}

.note-actions {
    display: flex;
    gap: 10px;
}

.note-actions button {
    padding: 8px 16px;
    border: none;
    border-radius: 6px;
    cursor: pointer;
    font-size: 14px;
    font-weight: 500;
    transition: background 0.3s ease;
}

.edit-btn {
    background: #28a745;
    color: white;
}

.edit-btn:hover {
    background: #218838;
}

.delete-btn {
    background: #dc3545;
    color: white;
}

.delete-btn:hover {
    background: #c82333;
}

/* Loading Spinner */
.loading {
    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;
}

.spinner {
    width: 50px;
    height: 50px;
    border: 4px solid #f3f3f3;
    border-top: 4px solid #3b82f6;
    border-radius: 50%;
    animation: spin 1s linear infinite;
}

@keyframes spin {
    0% { transform: rotate(0deg); }
    100% { transform: rotate(360deg); }
}

/* Message Display */
.message {
    position: fixed;
    top: 20px;
    right: 20px;
    padding: 15px 25px;
    border-radius: 8px;
    color: white;
    font-weight: 600;
    z-index: 1001;
    animation: slideIn 0.3s ease;
}

.message.success {
    background: #28a745;
}

.message.error {
    background: #dc3545;
}

.message.info {
    background: #17a2b8;
}

@keyframes slideIn {
    from {
        transform: translateX(100%);
        opacity: 0;
    }
    to {
        transform: translateX(0);
        opacity: 1;
    }
}

/* Modal Styles */
.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: 1002;
    animation: fadeIn 0.3s ease;
}

.modal-content {
    background: white;
    border-radius: 12px;
    width: 90%;
    max-width: 500px;
    max-height: 90vh;
    overflow: hidden;
    box-shadow: 0 20px 40px rgba(0, 0, 0, 0.15);
    animation: slideUp 0.3s ease;
}

.modal-header {
    background: linear-gradient(135deg, #60a5fa 0%, #22d3ee 100%);
    color: white;
    padding: 20px;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.modal-header h3 {
    margin: 0;
    font-size: 20px;
    font-weight: 600;
}

.close-btn {
    background: none;
    border: none;
    color: white;
    font-size: 24px;
    cursor: pointer;
    padding: 0;
    width: 30px;
    height: 30px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 50%;
    transition: background 0.3s ease;
}

.close-btn:hover {
    background: rgba(255, 255, 255, 0.2);
}

.modal-body {
    padding: 25px;
}

.modal-body input,
.modal-body textarea {
    width: 100%;
    padding: 15px;
    margin-bottom: 15px;
    border: 2px solid #e1e5e9;
    border-radius: 8px;
    font-size: 16px;
    font-family: inherit;
    resize: vertical;
}

.modal-body input:focus,
.modal-body textarea:focus {
    outline: none;
    border-color: #0ea5e9;
}

.modal-body textarea {
    min-height: 120px;
}

.modal-body p {
    color: #666;
    margin-bottom: 15px;
    line-height: 1.6;
}

.note-preview {
    background: #f8f9fa;
    padding: 15px;
    border-radius: 8px;
    border-left: 4px solid #0ea5e9;
    font-style: italic;
    color: #555;
}

.modal-footer {
    padding: 20px 25px;
    background: #f8f9fa;
    border-top: 1px solid #e9ecef;
    display: flex;
    gap: 15px;
    justify-content: flex-end;
}

.modal-footer button {
    padding: 12px 24px;
    border: none;
    border-radius: 8px;
    font-size: 16px;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s ease;
}

.cancel-btn {
    background: #6c757d;
    color: white;
}

.cancel-btn:hover {
    background: #5a6268;
}

.save-btn {
    background: linear-gradient(135deg, #3b82f6 0%, #06b6d4 100%);
    color: white;
}

.save-btn:hover {
    transform: translateY(-2px);
}

.delete-confirm-btn {
    background: #dc3545;
    color: white;
}

.delete-confirm-btn:hover {
    background: #c82333;
}

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

@keyframes slideUp {
    from {
        transform: translateY(50px);
        opacity: 0;
    }
    to {
        transform: translateY(0);
        opacity: 1;
    }
}

/* Utility Classes */
.hidden {
    display: none !important;
}

/* Responsive Design */
@media (max-width: 768px) {
    .container {
        padding: 10px;
    }
    
    .auth-form {
        padding: 30px 20px;
    }
    
    .app-header {
        padding: 20px;
        flex-direction: column;
        gap: 15px;
        text-align: center;
    }
    
    .notes-container {
        grid-template-columns: 1fr;
        padding: 20px;
    }
    
    .add-note {
        padding: 20px;
    }
}