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

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 50%, #667eea 100%);
    background-size: 200% 200%;
    background-attachment: fixed;
    min-height: 100vh;
    padding: 20px;
    animation: gradientShift 15s ease infinite;
}

@keyframes gradientShift {
    0%, 100% { background-position: 0% 50%; }
    50% { background-position: 100% 50%; }
}

.container {
    max-width: 900px;
    margin: 0 auto;
    background: rgba(255, 255, 255, 0.98);
    border-radius: 20px;
    box-shadow: 0 30px 80px rgba(0, 0, 0, 0.3);
    overflow: hidden;
    backdrop-filter: blur(10px);
    animation: slideUp 0.6s ease-out;
}

@keyframes slideUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

header {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    padding: 40px 30px;
    text-align: center;
    position: relative;
    overflow: hidden;
}

header::before {
    content: '';
    position: absolute;
    top: -50%;
    left: -50%;
    width: 200%;
    height: 200%;
    background: radial-gradient(circle, rgba(255,255,255,0.1) 0%, transparent 70%);
    animation: rotate 20s linear infinite;
}

@keyframes rotate {
    from { transform: rotate(0deg); }
    to { transform: rotate(360deg); }
}

header h1 {
    font-size: 2.5em;
    margin-bottom: 10px;
    position: relative;
    z-index: 1;
    text-shadow: 0 2px 10px rgba(0,0,0,0.2);
}

.subtitle {
    opacity: 0.95;
    font-size: 1.2em;
    position: relative;
    z-index: 1;
}

.status {
    padding: 15px 30px;
    margin: 20px 30px;
    border-radius: 8px;
    font-weight: 500;
}

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

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

.status.hidden {
    display: none;
}

form {
    padding: 30px;
}

.section {
    margin-bottom: 35px;
    animation: fadeIn 0.8s ease-out;
}

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

.section h2 {
    color: #667eea;
    font-size: 1.4em;
    margin-bottom: 20px;
    padding-bottom: 12px;
    border-bottom: 3px solid #f0f0f0;
    position: relative;
}

.section h2::after {
    content: '';
    position: absolute;
    bottom: -3px;
    left: 0;
    width: 60px;
    height: 3px;
    background: linear-gradient(90deg, #667eea, #764ba2);
    border-radius: 2px;
}

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

.form-group label {
    display: block;
    font-weight: 600;
    margin-bottom: 8px;
    color: #333;
}

.form-group input[type="text"],
.form-group input[type="url"],
.form-group input[type="password"],
.form-group input[type="number"],
.form-group select,
.form-group textarea {
    width: 100%;
    padding: 14px 16px;
    border: 2px solid #e8e8e8;
    border-radius: 10px;
    font-size: 1em;
    transition: all 0.3s ease;
    background: #fafafa;
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
}

.form-group textarea {
    resize: vertical;
    min-height: 100px;
    line-height: 1.6;
}

.form-group input:focus,
.form-group select:focus,
.form-group textarea:focus {
    outline: none;
    border-color: #667eea;
    background: white;
    box-shadow: 0 0 0 4px rgba(102, 126, 234, 0.1);
    transform: translateY(-2px);
}

.form-group small {
    display: block;
    margin-top: 5px;
    color: #666;
    font-size: 0.9em;
}

.form-group.checkbox {
    display: flex;
    align-items: center;
}

.form-group.checkbox input {
    width: auto;
    margin-right: 10px;
}

.form-group.checkbox label {
    margin-bottom: 0;
}

.actions {
    display: flex;
    gap: 15px;
    margin-top: 30px;
}

.btn {
    flex: 1;
    padding: 16px 32px;
    border: none;
    border-radius: 12px;
    font-size: 1.05em;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s ease;
    position: relative;
    overflow: hidden;
}

.btn::before {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    width: 0;
    height: 0;
    border-radius: 50%;
    background: rgba(255, 255, 255, 0.3);
    transform: translate(-50%, -50%);
    transition: width 0.6s, height 0.6s;
}

.btn:hover::before {
    width: 300px;
    height: 300px;
}

.btn-primary {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    box-shadow: 0 4px 15px rgba(102, 126, 234, 0.4);
}

.btn-primary:hover {
    transform: translateY(-3px);
    box-shadow: 0 8px 25px rgba(102, 126, 234, 0.5);
}

.btn-secondary {
    background: white;
    color: #667eea;
    border: 2px solid #667eea;
    box-shadow: 0 4px 15px rgba(102, 126, 234, 0.2);
}

.btn-secondary:hover {
    background: #f8f9ff;
    transform: translateY(-3px);
    box-shadow: 0 8px 25px rgba(102, 126, 234, 0.3);
}

.btn:disabled {
    opacity: 0.6;
    cursor: not-allowed;
    transform: none !important;
}

.btn:active {
    transform: translateY(-1px);
}

footer {
    background: linear-gradient(135deg, #f8f9fa 0%, #e9ecef 100%);
    padding: 25px 30px;
    text-align: center;
    color: #666;
    font-size: 0.95em;
    border-top: 1px solid #e0e0e0;
}

footer p {
    margin: 8px 0;
}

footer code {
    background: white;
    padding: 4px 10px;
    border-radius: 6px;
    font-family: 'Courier New', monospace;
    color: #667eea;
    border: 1px solid #e0e0e0;
    font-weight: 500;
}


/* 复选框美化 */
.form-group.checkbox input[type="checkbox"] {
    width: 20px;
    height: 20px;
    cursor: pointer;
    accent-color: #667eea;
}

/* 状态消息动画 */
.status {
    animation: slideDown 0.4s ease-out;
}

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

/* 响应式设计 */
@media (max-width: 768px) {
    body {
        padding: 10px;
    }
    
    .container {
        border-radius: 15px;
    }
    
    header {
        padding: 30px 20px;
    }
    
    header h1 {
        font-size: 2em;
    }
    
    form {
        padding: 20px;
    }
    
    .actions {
        flex-direction: column;
    }
    
    .btn {
        width: 100%;
        margin-bottom: 10px;
    }
}

/* 加载动画 */
@keyframes spin {
    to { transform: rotate(360deg); }
}

.btn:disabled::after {
    content: '';
    position: absolute;
    width: 16px;
    height: 16px;
    top: 50%;
    left: 50%;
    margin-left: -8px;
    margin-top: -8px;
    border: 2px solid rgba(255,255,255,0.3);
    border-radius: 50%;
    border-top-color: white;
    animation: spin 0.6s linear infinite;
}

/* 输入框图标提示 */
.form-group {
    position: relative;
}

.form-group label {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 10px;
}

.btn-reset {
    padding: 6px 12px;
    background: #f0f0f0;
    border: 1px solid #ddd;
    border-radius: 6px;
    font-size: 0.85em;
    cursor: pointer;
    transition: all 0.2s ease;
    color: #666;
    font-weight: 500;
}

.btn-reset:hover {
    background: #667eea;
    color: white;
    border-color: #667eea;
    transform: translateY(-1px);
}

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

/* 平滑滚动 */
html {
    scroll-behavior: smooth;
}

/* 选中文本样式 */
::selection {
    background: #667eea;
    color: white;
}

/* 表单行布局 - 让元素并排显示 */
.form-row {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 20px;
}

.checkbox-row {
    display: flex;
    gap: 30px;
    align-items: center;
}

.checkbox-row .form-group {
    margin-bottom: 0;
}

/* 响应式：小屏幕时恢复垂直布局 */
@media (max-width: 768px) {
    .form-row {
        grid-template-columns: 1fr;
        gap: 20px;
    }
    
    .checkbox-row {
        flex-direction: column;
        align-items: flex-start;
        gap: 15px;
    }
}