/* 服务条款复选框样式 */
.form-group.terms {
    margin: 20px 0;
}

.form-group.terms .checkbox-container {
    display: flex;
    align-items: center;
    cursor: pointer;
    position: relative;
    padding-left: 35px;
    margin-bottom: 12px;
    font-size: 16px;
    user-select: none;
}

.form-group.terms .checkbox-container input {
    position: absolute;
    opacity: 0;
    cursor: pointer;
    height: 0;
    width: 0;
}

.form-group.terms .checkmark {
    position: absolute;
    top: 0;
    left: 0;
    height: 24px;
    width: 24px;
    background-color: #f5f7fa;
    border: 2px solid #6c5ce7;
    border-radius: 4px;
    transition: all 0.3s;
}

.form-group.terms .checkbox-container:hover input ~ .checkmark {
    background-color: #f0f0f0;
}

.form-group.terms .checkbox-container input:checked ~ .checkmark {
    background-color: #6c5ce7;
}

.form-group.terms .checkmark:after {
    content: "";
    position: absolute;
    display: none;
}

.form-group.terms .checkbox-container input:checked ~ .checkmark:after {
    display: block;
}

.form-group.terms .checkbox-container .checkmark:after {
    left: 8px;
    top: 4px;
    width: 5px;
    height: 10px;
    border: solid white;
    border-width: 0 2px 2px 0;
    transform: rotate(45deg);
}

.form-group.terms .terms-text {
    margin-left: 10px;
    color: #333;
    transition: color 0.3s;
}

.form-group.terms .checkbox-container:hover .terms-text {
    color: #6c5ce7;
}

/* 基础重置 */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    --primary-color: #6c5ce7;
    --secondary-color: #a29bfe;
    --accent-color: #fd79a8;
    --text-color: #2d3436;
    --light-text: #f5f6fa;
    --glass-bg: rgba(255, 255, 255, 0.2);
    --glass-border: rgba(255, 255, 255, 0.3);
    --transition: all 0.3s ease;
    --border-radius: 8px;
    --box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
}

/* 基础样式 */
body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
    line-height: 1.6;
    color: var(--text-color);
    background-color: #f5f7fa;
    margin: 0;
    padding: 0;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

.main-content {
    flex: 1;
    display: flex;
    flex-direction: column;
}

/* 确保container在main-content中正确布局 */
.main-content .container {
    flex: 1;
    display: flex;
    flex-direction: column;
}

.container {
    width: 100%;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
    position: relative;
    z-index: 1;
}

/* 头部样式 */
.header {
    background: rgba(255, 255, 255, 0.8);
    backdrop-filter: blur(10px);
    padding: 1rem 0;
    box-shadow: var(--box-shadow);
    position: relative;
    z-index: 10;
}

.header .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    font-size: 1.8rem;
    font-weight: 700;
    color: var(--primary-color);
    text-decoration: none;
    display: flex;
    align-items: center;
    gap: 10px;
}

/* 主要内容区域 */
.main-content {
    flex: 1;
    padding: 2rem 0;
    position: relative;
}

/* 表单样式 */
.submission-form {
    background: rgba(255, 255, 255, 0.9);
    border-radius: var(--border-radius);
    padding: 2rem;
    box-shadow: var(--box-shadow);
    max-width: 800px;
    margin: 2rem auto;
    position: relative;
    z-index: 2;
}

.form-group {
    margin-bottom: 1.5rem;
}

.form-group label {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: 500;
    color: var(--text-color);
}

.form-control {
    width: 100%;
    padding: 0.75rem 1rem;
    border: 1px solid #ddd;
    border-radius: var(--border-radius);
    font-size: 1rem;
    transition: var(--transition);
}

.form-control:focus {
    border-color: var(--primary-color);
    outline: none;
    box-shadow: 0 0 0 2px rgba(108, 92, 231, 0.2);
}

textarea.form-control {
    min-height: 120px;
    resize: vertical;
}

.btn {
    display: inline-block;
    background: var(--primary-color);
    color: white;
    border: none;
    padding: 0.75rem 1.5rem;
    border-radius: var(--border-radius);
    font-size: 1rem;
    cursor: pointer;
    transition: var(--transition);
    text-align: center;
    text-decoration: none;
}

.btn:hover {
    background: #5a4fcf;
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(108, 92, 231, 0.3);
}

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

/* 页脚样式已移除，使用统一样式 */

/* 响应式设计 */
@media (max-width: 768px) {
    .container {
        padding: 0 15px;
    }
    
    .submission-form {
        padding: 1.5rem;
        margin: 1rem auto;
    }
    
    .btn {
        width: 100%;
    }
}

/* 动画效果 */
@keyframes fadeIn {
    from { opacity: 0; transform: translateY(20px); }
    to { opacity: 1; transform: translateY(0); }
}

.animate-fade-in {
    animation: fadeIn 0.6s ease-out forwards;
}

/* 状态消息 */
.status-message {
    padding: 1rem;
    margin: 1rem 0;
    border-radius: var(--border-radius);
    text-align: center;
    font-weight: 500;
}

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

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

/* 粒子背景 */
#particles-js {
    position: fixed;
    width: 100%;
    height: 100%;
    top: 0;
    left: 0;
    z-index: 0;
    pointer-events: none;
}

/* 加载指示器 */
.loader {
    border: 4px solid rgba(255, 255, 255, 0.3);
    border-radius: 50%;
    border-top: 4px solid var(--primary-color);
    width: 30px;
    height: 30px;
    animation: spin 1s linear infinite;
    margin: 20px auto;
    display: none;
}

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

/* 自定义复选框 */
.checkbox-container {
    display: flex;
    align-items: center;
    margin: 1rem 0;
    cursor: pointer;
}

.checkbox-container input[type="checkbox"] {
    display: none;
}

.checkbox-custom {
    width: 20px;
    height: 20px;
    border: 2px solid var(--primary-color);
    border-radius: 4px;
    margin-right: 10px;
    position: relative;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: var(--transition);
}

.checkbox-container input[type="checkbox"]:checked + .checkbox-custom {
    background-color: var(--primary-color);
}

.checkbox-custom::after {
    content: '✓';
    color: white;
    font-size: 14px;
    display: none;
}

.checkbox-container input[type="checkbox"]:checked + .checkbox-custom::after {
    display: block;
}

.checkbox-label {
    font-size: 0.9rem;
    color: var(--text-color);
}

.checkbox-label a {
    color: var(--primary-color);
    text-decoration: none;
    font-weight: 500;
}

.checkbox-label a:hover {
    text-decoration: underline;
}

/* 重复的header样式已移除，使用统一样式 */

/* 重复的title样式已移除，使用统一样式 */

/* 重复的form样式已移除，使用统一样式 */

.form-group label {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: 600;
    color: var(--text-color);
}

.form-group input[type="text"],
.form-group input[type="email"],
.form-group input[type="url"],
.form-group select,
.form-group textarea {
    width: 100%;
    padding: 0.8rem 1rem;
    border: 2px solid #e0e0e0;
    border-radius: var(--border-radius);
    font-size: 1rem;
    transition: var(--transition);
    background-color: #fff;
}

.form-group input:focus,
.form-group select:focus,
.form-group textarea:focus {
    border-color: var(--primary-color);
    outline: none;
    box-shadow: 0 0 0 3px rgba(108, 92, 231, 0.2);
}

.form-group textarea {
    min-height: 120px;
    resize: vertical;
}

.checkbox-group {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    margin: 1.5rem 0;
}

.checkbox-group input[type="checkbox"] {
    width: auto;
    margin: 0;
}

.btn {
    background: var(--primary-color);
    color: white;
    border: none;
    padding: 1rem 2rem;
    border-radius: var(--border-radius);
    font-size: 1.1rem;
    font-weight: 600;
    cursor: pointer;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
    transition: var(--transition);
    text-decoration: none;
}

.btn:hover {
    background: #5a4bc9;
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
}

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

.required {
    color: #e74c3c;
    margin-left: 0.25rem;
}

/* 响应式设计 */
@media (max-width: 768px) {
    body {
        padding: 1rem;
    }
    
    .container {
        padding: 1.5rem;
    }
    
    .title {
        font-size: 2rem;
    }
}

/* 状态消息 */
.status-message {
    margin-top: 1.5rem;
    padding: 1rem;
    border-radius: var(--border-radius);
    font-weight: 500;
    display: none;
}

.status-message.show {
    display: block;
    animation: fadeIn 0.3s ease-in-out;
}

.status-message.error {
    background-color: #ffebee;
    color: #c62828;
    border-left: 4px solid #c62828;
}

.status-message.success {
    background-color: #e8f5e9;
    color: #2e7d32;
    border-left: 4px solid #2e7d32;
}

/* 重复的fadeIn动画已移除，使用统一样式 */

/* 加载动画 */
.loading {
    display: inline-block;
    width: 1.2rem;
    height: 1.2rem;
    border: 3px solid rgba(255, 255, 255, 0.3);
    border-radius: 50%;
    border-top-color: white;
    animation: spin 1s ease-in-out infinite;
}

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

/* 页脚样式已移除，使用统一样式 */

/* 背景效果 */
.background {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: -1;
    overflow: hidden;
}

.background-overlay {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: linear-gradient(135deg, #6c5ce7 0%, #a29bfe 100%);
    opacity: 0.1;
}

.particles {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    --shadow: 0 8px 32px 0 rgba(31, 38, 135, 0.37);
    --blur: blur(12px);
}

/* 重复的body样式已移除，使用统一样式 */

/* 樱花飘落效果 */
@keyframes fall {
    0% {
        transform: translateY(-10%) rotate(0deg);
        opacity: 0;
    }
    10% {
        opacity: 1;
    }
    90% {
        opacity: 1;
    }
    100% {
        transform: translateY(100vh) rotate(360deg);
        opacity: 0;
    }
}

/* 樱花容器 */
.sakura-container {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    pointer-events: none;
    z-index: -1;
    overflow: hidden;
}

.sakura {
    position: absolute;
    color: #ffb6c1;
    font-size: 20px;
    animation: fall linear infinite;
    user-select: none;
    z-index: -1;
}

/* 白色毛玻璃背景 */
.background {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: -2;
    background: linear-gradient(135deg, #fff5f5 0%, #f0f5ff 100%);
    overflow: hidden;
}

/* 添加一些微妙的纹理 */
.background::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: 
        radial-gradient(circle at 10% 20%, rgba(255,255,255,0.3) 0%, transparent 20%),
        radial-gradient(circle at 90% 80%, rgba(200,220,255,0.3) 0%, transparent 20%),
        radial-gradient(circle at 50% 50%, rgba(255,255,255,0.5) 0%, transparent 40%);
    animation: gradientMove 15s ease infinite;
    background-size: 200% 200%;
}

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

.background-overlay {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(255, 255, 255, 0.7);
    backdrop-filter: blur(15px) saturate(180%);
    -webkit-backdrop-filter: blur(15px) saturate(180%);
    box-shadow: inset 0 0 200px rgba(255,255,255,0.5);
}

/* 重复的container样式已移除，使用统一样式 */

/* 重复的header样式已移除，使用统一样式 */

/* 重复的title样式已移除，使用统一样式 */

.subtitle {
    font-size: 1.2rem;
    color: rgba(255, 255, 255, 0.9);
    margin-top: 1rem;
}

/* 表单样式 */
.submission-form {
    background: rgba(255, 255, 255, 0.8);
    backdrop-filter: blur(12px) saturate(180%);
    -webkit-backdrop-filter: blur(12px) saturate(180%);
    border: 1px solid rgba(255, 255, 255, 0.8);
    border-radius: 15px;
    padding: 2.5rem;
    box-shadow: 0 8px 32px 0 rgba(31, 38, 135, 0.1);
    transition: all 0.3s ease;
    position: relative;
    overflow: hidden;
    color: #333;
    text-shadow: 0 1px 2px rgba(255, 255, 255, 0.8);
}

/* 添加微妙的边框高光 */
.submission-form::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 1px;
    background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.8), transparent);
}

.submission-form:hover {
    transform: translateY(-5px);
    box-shadow: 0 15px 30px rgba(0, 0, 0, 0.2);
}

.form-group {
    margin-bottom: 1.8rem;
    position: relative;
    animation: fadeIn 0.8s ease-out;
    animation-fill-mode: both;
}

.form-group:nth-child(1) { animation-delay: 0.1s; }
.form-group:nth-child(2) { animation-delay: 0.2s; }
.form-group:nth-child(3) { animation-delay: 0.3s; }
.form-group:nth-child(4) { animation-delay: 0.4s; }
.form-group:nth-child(5) { animation-delay: 0.5s; }
.form-group:nth-child(6) { animation-delay: 0.6s; }

label {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: 600;
    color: #333;
    font-size: 1.05rem;
    display: flex;
    align-items: center;
    gap: 5px;
}

.required {
    color: #ff4757;
    margin-left: 2px;
}

input[type="text"],
input[type="email"],
input[type="url"],
select,
textarea {
    width: 100%;
    padding: 12px 15px;
    border: 1px solid rgba(0, 0, 0, 0.1);
    border-radius: 8px;
    background: rgba(255, 255, 255, 0.9);
    font-size: 1rem;
    color: var(--text-color);
    transition: var(--transition);
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.05);
}

/* 表单提示文本 */
.form-hint {
    display: block;
    margin-top: 6px;
    font-size: 0.85rem;
    color: #666;
    font-style: italic;
}

input[type="text"]:focus,
input[type="email"]:focus,
select:focus,
textarea:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(108, 92, 231, 0.2);
    background: white;
}

textarea {
    resize: vertical;
    min-height: 120px;
}

/* 文件上传区域 */
.file-upload {
    margin-top: 2rem;
}

.file-upload-area {
    border: 2px dashed rgba(0, 0, 0, 0.1);
    border-radius: 12px;
    padding: 2.5rem 2rem;
    text-align: center;
    cursor: pointer;
    transition: all 0.3s ease;
    background: rgba(255, 255, 255, 0.5);
    margin-top: 1rem;
    position: relative;
    overflow: hidden;
}

.file-upload-area::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: linear-gradient(135deg, rgba(255,255,255,0.3) 0%, rgba(255,255,255,0) 100%);
    z-index: 0;
}

.file-upload-area:hover {
    background: rgba(255, 255, 255, 0.7);
    border-color: rgba(0, 0, 0, 0.2);
    transform: translateY(-2px);
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.05);
}

.file-upload-area i {
    font-size: 2.5rem;
    color: var(--light-text);
    margin-bottom: 1rem;
    display: block;
}

.file-upload-area p {
    color: var(--light-text);
    margin: 0;
}

#file {
    display: none;
}

#fileInfo {
    margin-top: 0.5rem;
    font-size: 0.9rem;
    color: var(--light-text);
}

/* Checkbox */
.checkbox-group {
    display: flex;
    align-items: center;
    margin: 1.5rem 0;
}

.checkbox-group input[type="checkbox"] {
    width: auto;
    margin-right: 10px;
    transform: scale(1.2);
}

.checkbox-group label {
    margin-bottom: 0;
    display: flex;
    align-items: center;
}

.checkbox-group a {
    color: var(--light-text);
    text-decoration: underline;
    margin: 0 3px;
    transition: var(--transition);
}

.checkbox-group a:hover {
    color: var(--accent-color);
}

/* 按钮样式 */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 14px 32px;
    background: rgba(74, 107, 255, 0.9);
    color: white;
    border: none;
    border-radius: 12px;
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    text-decoration: none;
    box-shadow: 0 4px 20px rgba(74, 107, 255, 0.2);
    overflow: hidden;
    position: relative;
    z-index: 1;
    backdrop-filter: blur(5px);
    -webkit-backdrop-filter: blur(5px);
    border: 1px solid rgba(255, 255, 255, 0.5);
}

.btn::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 0;
    height: 100%;
    background: linear-gradient(45deg, var(--accent-color), #ff9ff3);
    transition: var(--transition);
    z-index: -1;
}

.btn:hover::before {
    width: 100%;
}

.btn i {
    margin-left: 8px;
    transition: var(--transition);
}

.btn:hover {
    transform: translateY(-3px);
    box-shadow: 0 7px 20px rgba(108, 92, 231, 0.4);
}

.btn:hover i {
    transform: translateX(5px);
}

.submit-btn {
    width: 100%;
    padding: 15px;
    font-size: 1.1rem;
    margin-top: 1rem;
}

/* Success & Error Messages */
.success-message,
.error-message {
    background: rgba(255, 255, 255, 0.9);
    padding: 2rem;
    border-radius: 10px;
    text-align: center;
    margin-bottom: 2rem;
    animation: fadeIn 0.8s ease-out;
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.1);
}

.success-message {
    border-left: 5px solid #2ecc71;
}

.error-message {
    border-left: 5px solid #e74c3c;
    margin-bottom: 2rem;
}

.success-message i {
    font-size: 3rem;
    color: #2ecc71;
    margin-bottom: 1rem;
    display: block;
}

.error-message i {
    font-size: 2rem;
    color: #e74c3c;
    margin-right: 10px;
}

.error-message p {
    display: inline;
    color: #e74c3c;
    font-weight: 600;
}

/* Footer */
.footer {
    text-align: center;
    padding: 2rem 1rem;
    color: #555;
    font-size: 0.85rem;
    margin-top: auto;
    position: relative;
    z-index: 100;
    background: rgba(255, 255, 255, 0.98);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border-top: 2px solid rgba(108, 92, 231, 0.15);
    box-shadow: 0 -4px 20px rgba(0, 0, 0, 0.08);
    clear: both;
    width: 100%;
    flex-shrink: 0;
}

.footer p {
    margin: 0;
    padding: 0;
    font-weight: 500;
}

/* 类别选择弹窗样式 */
.category-modal {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.5);
    z-index: 1000;
    overflow-y: auto;
    padding: 20px 0;
}

.category-modal.show {
    display: block;
}

.category-modal .modal-content {
    background-color: #fff;
    margin: 40px auto;
    padding: 30px;
    border-radius: 15px;
    max-width: 600px;
    width: 90%;
    box-shadow: 0 10px 40px rgba(0, 0, 0, 0.2);
    animation: slideUp 0.3s ease-out;
}

.category-modal h2 {
    text-align: center;
    color: #333;
    margin-bottom: 10px;
    font-size: 1.8rem;
}

.category-modal p {
    text-align: center;
    color: #666;
    margin-bottom: 30px;
    font-size: 1rem;
}

.category-options {
    display: grid;
    gap: 20px;
    grid-template-columns: 1fr;
}

.category-btn {
    display: flex;
    align-items: center;
    padding: 20px;
    border: 2px solid #e0e0e0;
    border-radius: 12px;
    background: #fff;
    cursor: pointer;
    transition: all 0.3s ease;
    text-align: left;
}

.category-btn:hover {
    border-color: #6c5ce7;
    transform: translateY(-2px);
    box-shadow: 0 5px 20px rgba(108, 92, 231, 0.2);
}

.category-icon {
    font-size: 2rem;
    margin-right: 20px;
}

.category-title {
    font-weight: 600;
    color: #333;
    margin-bottom: 5px;
    font-size: 1.1rem;
}

.category-desc {
    color: #666;
    font-size: 0.9rem;
}

/* 移动端优化 */
@media (max-width: 480px) {
    .container {
        padding: 0 10px;
    }
    
    .category-modal .modal-content {
        margin: 10px auto;
        padding: 15px;
        width: 98%;
        max-height: 90vh;
        overflow-y: auto;
    }
    
    .category-modal h2 {
        font-size: 1.5rem;
        margin-bottom: 15px;
    }
    
    .category-modal p {
        font-size: 0.9rem;
        margin-bottom: 20px;
    }
    
    .category-options {
        grid-template-columns: 1fr;
        gap: 15px;
    }
    
    .category-btn {
        flex-direction: column;
        text-align: center;
        padding: 20px 15px;
        min-height: 120px;
    }
    
    .category-icon {
        margin-right: 0;
        margin-bottom: 10px;
        font-size: 2rem;
    }
    
    .category-title {
        font-size: 1rem;
        margin-bottom: 8px;
    }
    
    .category-desc {
        font-size: 0.8rem;
        line-height: 1.3;
    }
    
    .submission-form {
        padding: 1rem 0.5rem;
    }
    
    .form-group {
        margin-bottom: 1rem;
    }
    
    .form-group label {
        font-size: 0.9rem;
        margin-bottom: 0.3rem;
    }
    
    .form-group input,
    .form-group select,
    .form-group textarea {
        font-size: 16px; /* 防止iOS缩放 */
        padding: 12px;
        border-radius: 8px;
    }
    
    .btn {
        padding: 15px 20px;
        font-size: 16px;
        width: 100%;
        margin: 10px 0;
    }
    
    .submit-btn {
        padding: 15px;
        font-size: 16px;
        font-weight: 600;
    }
}

/* 平板端优化 */
@media (min-width: 481px) and (max-width: 768px) {
    .container {
        max-width: 700px;
        padding: 0 20px;
    }
    
    .category-options {
        grid-template-columns: repeat(2, 1fr);
        gap: 15px;
    }
    
    .category-modal .modal-content {
        padding: 25px;
        max-width: 650px;
    }
    
    .submission-form {
        padding: 2rem;
        max-width: 700px;
    }
    
    .form-group input,
    .form-group select,
    .form-group textarea {
        width: 100%;
        max-width: 400px;
    }
    
    .form-group textarea {
        max-width: 500px;
        min-height: 100px;
    }
}

/* 桌面端优化 */
@media (min-width: 769px) and (max-width: 1199px) {
    .container {
        max-width: 900px;
        padding: 0 30px;
    }
    
    .category-modal .modal-content {
        margin: 50px auto;
        padding: 35px;
        max-width: 700px;
    }
    
    .category-modal h2 {
        font-size: 2rem;
        margin-bottom: 20px;
    }
    
    .category-modal p {
        font-size: 1.1rem;
        margin-bottom: 35px;
    }
    
    .category-options {
        grid-template-columns: repeat(3, 1fr);
        gap: 20px;
    }
    
    .category-btn {
        padding: 25px 20px;
        min-height: 140px;
        transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    }
    
    .category-btn:hover {
        transform: translateY(-5px);
        box-shadow: 0 15px 40px rgba(108, 92, 231, 0.3);
        border-color: #6c5ce7;
        background: linear-gradient(135deg, rgba(108, 92, 231, 0.05), rgba(255, 255, 255, 0.95));
    }
    
    .category-icon {
        font-size: 2.5rem;
        margin-bottom: 15px;
    }
    
    .category-title {
        font-size: 1.2rem;
        margin-bottom: 10px;
        font-weight: 700;
    }
    
    .category-desc {
        font-size: 0.95rem;
        line-height: 1.5;
    }
    
    .submission-form {
        padding: 2.5rem;
        margin: 2rem auto;
        max-width: 900px;
        width: 100%;
    }
    
    .form-group {
        margin-bottom: 2rem;
    }
    
    .form-group label {
        font-size: 1rem;
        margin-bottom: 0.8rem;
        font-weight: 600;
    }
    
    .form-group input,
    .form-group select,
    .form-group textarea {
        font-size: 16px;
        padding: 15px;
        border-radius: 12px;
        border: 2px solid #e0e0e0;
        transition: all 0.3s ease;
        width: 100%;
        max-width: 700px;
    }
    
    .form-group textarea {
        max-width: 800px;
        min-height: 120px;
        resize: vertical;
    }
    
    .form-group input:focus,
    .form-group select:focus,
    .form-group textarea:focus {
        border-color: #6c5ce7;
        box-shadow: 0 0 0 3px rgba(108, 92, 231, 0.1);
        outline: none;
    }
    
    .btn {
        padding: 15px 30px;
        font-size: 16px;
        border-radius: 12px;
        font-weight: 600;
        transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    }
    
    .submit-btn {
        padding: 18px 40px;
        font-size: 18px;
        font-weight: 700;
        background: linear-gradient(135deg, #6c5ce7, #8a63ff);
        border: none;
        color: white;
    }
    
    .submit-btn:hover {
        transform: translateY(-2px);
        box-shadow: 0 10px 30px rgba(108, 92, 231, 0.4);
    }
}

/* 大屏幕桌面端优化 */
@media (min-width: 1200px) {
    .container {
        max-width: 1000px;
        padding: 0 40px;
    }
    
    .category-modal .modal-content {
        margin: 60px auto;
        padding: 45px;
        max-width: 900px;
        border-radius: 20px;
    }
    
    .category-modal h2 {
        font-size: 2.2rem;
        margin-bottom: 25px;
    }
    
    .category-modal p {
        font-size: 1.2rem;
        margin-bottom: 40px;
    }
    
    .category-options {
        gap: 30px;
    }
    
    .category-btn {
        padding: 30px 25px;
        min-height: 160px;
        border-radius: 16px;
    }
    
    .category-btn:hover {
        transform: translateY(-8px);
        box-shadow: 0 20px 50px rgba(108, 92, 231, 0.35);
    }
    
    .category-icon {
        font-size: 3rem;
        margin-bottom: 20px;
    }
    
    .category-title {
        font-size: 1.3rem;
        margin-bottom: 12px;
    }
    
    .category-desc {
        font-size: 1rem;
        line-height: 1.6;
    }
    
    .submission-form {
        padding: 3rem;
        margin: 3rem auto;
        max-width: 1000px;
        width: 100%;
        border-radius: 20px;
    }
    
    .form-group {
        margin-bottom: 2.5rem;
    }
    
    .form-group label {
        font-size: 1.1rem;
        margin-bottom: 1rem;
    }
    
    .form-group input,
    .form-group select,
    .form-group textarea {
        font-size: 16px;
        padding: 18px;
        border-radius: 14px;
        border: 2px solid #e5e5e5;
        width: 100%;
        max-width: 800px;
    }
    
    .form-group textarea {
        max-width: 900px;
        min-height: 140px;
        resize: vertical;
    }
    
    .btn {
        padding: 18px 35px;
        font-size: 17px;
        border-radius: 14px;
    }
    
    .submit-btn {
        padding: 20px 50px;
        font-size: 19px;
        font-weight: 700;
    }
    
    .submit-btn:hover {
        transform: translateY(-3px);
        box-shadow: 0 15px 40px rgba(108, 92, 231, 0.45);
    }
}

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

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

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

/* Particles.js */
#particles-js {
    position: absolute;
    width: 100%;
    height: 100%;
    z-index: -1;
}

/* 提交成功动画 */
/* 重复的fadeIn动画已移除，使用统一样式 */

@keyframes checkmark {
    0% { transform: scale(0); opacity: 0; }
    50% { transform: scale(1.2); opacity: 0.8; }
    100% { transform: scale(1); opacity: 1; }
}

.success-animation {
    text-align: center;
    padding: 40px 20px;
    background: rgba(255, 255, 255, 0.9);
    border-radius: 10px;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.1);
    max-width: 500px;
    margin: 20px auto;
    animation: fadeIn 0.6s ease-out forwards;
    backdrop-filter: blur(10px);
    border: 1px solid rgba(255, 255, 255, 0.2);
}

.success-animation .checkmark {
    width: 80px;
    height: 80px;
    border-radius: 50%;
    display: inline-block;
    background-color: #4CAF50;
    position: relative;
    margin: 20px 0;
    animation: checkmark 0.6s ease-out;
    box-shadow: 0 4px 15px rgba(76, 175, 80, 0.3);
}

.success-animation .checkmark:after {
    content: '';
    position: absolute;
    left: 28px;
    top: 15px;
    width: 25px;
    height: 40px;
    border: solid white;
    border-width: 0 4px 4px 0;
    transform: rotate(45deg);
    animation: checkmarkLine 0.6s ease-out 0.3s both;
}

.success-animation h2 {
    color: #2c3e50;
    margin: 20px 0 10px;
    font-size: 2em;
}

.success-animation p {
    color: #555;
    margin: 10px 0 25px;
    line-height: 1.6;
}

.success-animation .btn {
    background: linear-gradient(135deg, #4CAF50, #45a049);
    color: white;
    border: none;
    padding: 12px 30px;
    border-radius: 50px;
    cursor: pointer;
    font-size: 1.1em;
    transition: all 0.3s ease;
    text-decoration: none;
    display: inline-block;
    margin-top: 20px;
    box-shadow: 0 4px 15px rgba(76, 175, 80, 0.3);
}

.success-animation .btn:hover {
    transform: translateY(-3px);
    box-shadow: 0 6px 20px rgba(76, 175, 80, 0.4);
    background: linear-gradient(135deg, #45a049, #3d8b40);
}

/* 技术支持信息样式 */
.tech-info {
    margin: 20px 0;
    padding: 10px 0;
    border-top: 1px solid #e0e0e0;
    border-bottom: 1px solid #e0e0e0;
}

.tech-info p {
    color: #666;
    font-size: 14px;
    margin: 5px 0;
    font-style: italic;
}

@keyframes checkmarkLine {
    0% { height: 0; width: 0; opacity: 0; }
    100% { height: 40px; width: 25px; opacity: 1; }
}

/* Responsive Design */
@media (max-width: 768px) {
    .container {
        padding: 1rem;
        margin: 1rem auto;
    }
    
    .title {
        font-size: 2.2rem;
    }
    
    .subtitle {
        font-size: 1rem;
    }
    
    .footer {
        padding: 1.5rem 1rem;
        font-size: 0.8rem;
    }
    
    .footer p {
        line-height: 1.4;
    }
    
    .submission-form {
        padding: 1.5rem;
    }
}

/* Custom Scrollbar */
::-webkit-scrollbar {
    width: 8px;
}

::-webkit-scrollbar-track {
    background: rgba(255, 255, 255, 0.1);
}

::-webkit-scrollbar-thumb {
    background: var(--primary-color);
    border-radius: 4px;
}

::-webkit-scrollbar-thumb:hover {
    background: var(--secondary-color);
}

/* Form Validation */
input:invalid,
textarea:invalid,
select:invalid {
    border-color: #ff6b6b;
}

input:focus:invalid,
textarea:focus:invalid,
select:focus:invalid {
    box-shadow: 0 0 0 3px rgba(255, 107, 107, 0.3);
}

/* Loading Animation */
@keyframes spin {
    to { transform: rotate(360deg); }
}

.loading {
    display: inline-block;
    width: 20px;
    height: 20px;
    border: 3px solid rgba(255, 255, 255, 0.3);
    border-radius: 50%;
    border-top-color: white;
    animation: spin 1s ease-in-out infinite;
    margin-right: 8px;
}