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

body {
    font-family: Arial, sans-serif;
    line-height: 1.6;
    background-color: #f5f5f5;
    padding: 20px;
}

.container {
    max-width: 800px;
    margin: 0 auto;
    background: white;
    padding: 30px;
    border-radius: 5px;
    box-shadow: 0 2px 5px rgba(0,0,0,0.1);
}

h1, h2 {
    color: #333;
    margin-bottom: 20px;
    text-align: center;
}

.form-group {
    margin-bottom: 15px;
}

label {
    display: block;
    margin-bottom: 5px;
    font-weight: bold;
    color: #555;
}

input, select {
    width: 100%;
    padding: 10px;
    border: 1px solid #ddd;
    border-radius: 4px;
    font-size: 16px;
}

input:focus, select:focus {
    outline: none;
    border-color: #007bff;
}

button {
    background-color: #007bff;
    color: white;
    padding: 12px 20px;
    border: none;
    border-radius: 4px;
    cursor: pointer;
    font-size: 16px;
    width: 100%;
}

button:hover {
    background-color: #0056b3;
}

button.danger {
    background-color: #dc3545;
}

button.danger:hover {
    background-color: #c82333;
}

.nav {
    display: flex;
    gap: 10px;
    margin-bottom: 20px;
    justify-content: space-between;
    align-items: stretch;
    flex-wrap: wrap;
}

.nav a {
    padding: 12px 16px;
    background: #6c757d;
    color: white;
    text-decoration: none;
    border-radius: 4px;
    text-align: center;
    flex: 1;
    min-width: 120px;
    font-size: 14px;
    display: flex;
    align-items: center;
    justify-content: center;
    line-height: 1.4;
}

.nav a:hover {
    background: #545b62;
}

.nav button {
    background-color: #dc3545;
    color: white;
    padding: 12px 16px;
    border: none;
    border-radius: 4px;
    cursor: pointer;
    font-size: 14px;
    flex: 1;
    min-width: 120px;
    display: flex;
    align-items: center;
    justify-content: center;
    line-height: 1.4;
}

.nav button:hover {
    background-color: #c82333;
}

.message {
    padding: 15px;
    margin: 15px 0;
    border-radius: 4px;
    text-align: center;
}

.message.success {
    background-color: #d4edda;
    color: #155724;
    border: 1px solid #c3e6cb;
}

.message.error {
    background-color: #f8d7da;
    color: #721c24;
    border: 1px solid #f5c6cb;
}

.hidden {
    display: none !important;
}

.user-info {
    background: #f8f9fa;
    padding: 15px;
    border-radius: 4px;
    margin-bottom: 20px;
    text-align: center;
}

.section {
    margin: 30px 0;
    padding: 20px;
    border: 1px solid #ddd;
    border-radius: 4px;
}

/* Анимация загрузки */
@keyframes pulse {
    0% { opacity: 1; }
    50% { opacity: 0.5; }
    100% { opacity: 1; }
}

.loading {
    text-align: center;
    padding: 40px;
    color: #6c757d;
    font-style: italic;
    animation: pulse 1.5s ease-in-out infinite;
}

/* Улучшения для форм */
.form-group input:invalid {
    border-color: #dc3545;
}

.form-group input:valid {
    border-color: #28a745;
}

/* Стили для отключенных кнопок */
button:disabled {
    background-color: #6c757d;
    cursor: not-allowed;
    opacity: 0.6;
}

button:disabled:hover {
    background-color: #6c757d;
}

/* Адаптивность для мобильных */
@media (max-width: 768px) {
    .nav {
        flex-direction: column;
    }
    
    .nav a,
    .nav button {
        width: 100%;
        min-width: auto;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 15px;
    }
    
    .section {
        padding: 15px;
    }
    
    .nav a,
    .nav button {
        font-size: 13px;
        padding: 10px 12px;
    }
}