* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Segoe UI', 'Microsoft YaHei', sans-serif;
}

body {
    background-color: #f8f9fa;
    color: #333;
    line-height: 1.6;
    padding: 20px;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    background-image: linear-gradient(135deg, #f5f7fa 0%, #e4edf5 100%);
}

.container {
    width: 100%;
    max-width: 800px;
    margin: 0 auto;
    padding: 20px;
}

header {
    text-align: center;
    margin-bottom: 40px;
    padding: 20px;
    border-radius: 12px;
    background: rgba(255, 255, 255, 0.9);
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.05);
    border: 1px solid rgba(255, 255, 255, 0.8);
}

h1 {
    color: #2c3e50;
    font-size: 2.5rem;
    margin-bottom: 10px;
    font-weight: 600;
}

.subtitle {
    color: #7f8c8d;
    font-size: 1.1rem;
    margin-bottom: 15px;
}

.author-note {
    background-color: #f8f9fa;
    padding: 15px;
    border-radius: 8px;
    border-left: 4px solid #3498db;
    margin-top: 15px;
    font-style: italic;
    color: #555;
}

.form-container {
    background-color: white;
    padding: 30px;
    border-radius: 12px;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.08);
    margin-bottom: 30px;
    transition: all 0.3s ease;
}

.form-container:hover {
    box-shadow: 0 15px 35px rgba(0, 0, 0, 0.1);
}

.form-group {
    margin-bottom: 25px;
}

label {
    display: block;
    margin-bottom: 8px;
    color: #2c3e50;
    font-weight: 500;
}

input, textarea {
    width: 100%;
    padding: 14px;
    border: 1px solid #ddd;
    border-radius: 8px;
    font-size: 16px;
    transition: border 0.3s;
}

input:focus, textarea:focus {
    outline: none;
    border-color: #3498db;
    box-shadow: 0 0 0 2px rgba(52, 152, 219, 0.2);
}

textarea {
    min-height: 200px;
    resize: vertical;
}

.required::after {
    content: " *";
    color: #e74c3c;
}

.submit-btn {
    background-color: #3498db;
    color: white;
    border: none;
    padding: 16px 32px;
    font-size: 18px;
    border-radius: 8px;
    cursor: pointer;
    transition: background-color 0.3s, transform 0.2s;
    width: 100%;
    font-weight: 600;
    letter-spacing: 1px;
}

.submit-btn:hover {
    background-color: #2980b9;
    transform: translateY(-2px);
    box-shadow: 0 5px 15px rgba(52, 152, 219, 0.3);
}

.submit-btn:active {
    transform: translateY(0);
}

.submit-btn:disabled {
    background-color: #95a5a6;
    cursor: not-allowed;
    transform: none;
    box-shadow: none;
}

.thank-you {
    text-align: center;
    padding: 30px;
    background-color: white;
    border-radius: 12px;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.08);
    display: none;
    margin-top: 20px;
    animation: fadeIn 0.8s ease;
}

.thank-you.show {
    display: block;
}

.thank-you h2 {
    color: #27ae60;
    font-size: 2rem;
    margin-bottom: 15px;
}

.thank-you p {
    font-size: 1.1rem;
    color: #555;
    margin-bottom: 10px;
}

.signature {
    margin-top: 25px;
    font-style: italic;
    color: #7f8c8d;
    font-size: 1.2rem;
}

.signature .name {
    font-weight: bold;
    color: #2c3e50;
}

footer {
    text-align: center;
    margin-top: 40px;
    color: #7f8c8d;
    font-size: 0.9rem;
}

.counter {
    text-align: right;
    font-size: 14px;
    color: #7f8c8d;
    margin-top: 5px;
}

.error-message {
    color: #e74c3c;
    background-color: #fdf2f2;
    padding: 12px;
    border-radius: 8px;
    margin-top: 15px;
    border-left: 4px solid #e74c3c;
    display: none;
}

.error-message.show {
    display: block;
}

.loading {
    display: inline-block;
    width: 20px;
    height: 20px;
    border: 3px solid rgba(255,255,255,.3);
    border-radius: 50%;
    border-top-color: #fff;
    animation: spin 1s ease-in-out infinite;
    margin-right: 10px;
}

.success-message {
    color: #27ae60;
    background-color: #f0f9f0;
    padding: 12px;
    border-radius: 8px;
    margin-top: 15px;
    border-left: 4px solid #27ae60;
    display: none;
}

.success-message.show {
    display: block;
}

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

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(20px); }
    to { opacity: 1; transform: translateY(0); }
}

@media (max-width: 768px) {
    .container {
        padding: 10px;
    }
    
    h1 {
        font-size: 2rem;
    }
    
    .form-container {
        padding: 20px;
    }
}

.icon {
    margin-right: 8px;
    color: #3498db;
}