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

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    min-height: 100vh;
    padding: 20px;
    color: #333;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    background: white;
    border-radius: 20px;
    padding: 40px;
    box-shadow: 0 20px 60px rgba(0, 0, 0, 0.3);
}

header {
    text-align: center;
    margin-bottom: 40px;
}

header h1 {
    font-size: 2.5em;
    color: #667eea;
    margin-bottom: 10px;
}

.subtitle {
    color: #666;
    font-size: 1.1em;
}

.upload-section {
    margin-bottom: 60px;
}

.upload-section h2,
.history-section h2 {
    font-size: 1.8em;
    color: #333;
    margin-bottom: 20px;
    padding-bottom: 10px;
    border-bottom: 2px solid #667eea;
}

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

.form-group label {
    display: block;
    margin-bottom: 8px;
    font-weight: 600;
    color: #555;
}

.form-group input[type="file"] {
    width: 100%;
    padding: 12px;
    border: 2px dashed #ddd;
    border-radius: 8px;
    background: #f9f9f9;
    cursor: pointer;
    transition: all 0.3s;
}

.form-group input[type="file"]:hover {
    border-color: #667eea;
    background: #f0f0ff;
}

.form-group input[type="text"] {
    width: 100%;
    padding: 12px;
    border: 2px solid #ddd;
    border-radius: 8px;
    font-size: 1em;
    transition: border-color 0.3s;
}

.form-group input[type="text"]:focus {
    outline: none;
    border-color: #667eea;
}

.preview {
    margin-top: 10px;
    min-height: 100px;
}

.preview-img {
    max-width: 200px;
    max-height: 200px;
    border-radius: 8px;
    box-shadow: 0 4px 8px rgba(0, 0, 0, 0.1);
    object-fit: cover;
}

.btn-primary {
    width: 100%;
    padding: 15px;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    border: none;
    border-radius: 8px;
    font-size: 1.1em;
    font-weight: 600;
    cursor: pointer;
    transition: transform 0.2s, box-shadow 0.2s;
}

.btn-primary:hover:not(:disabled) {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(102, 126, 234, 0.4);
}

.btn-primary:disabled {
    opacity: 0.6;
    cursor: not-allowed;
}

.error-message {
    margin-top: 15px;
    padding: 12px;
    background: #fee;
    color: #c33;
    border-radius: 8px;
    border-left: 4px solid #c33;
}

.loading {
    text-align: center;
    padding: 40px;
    color: #666;
}

.history-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: 20px;
    margin-top: 20px;
}

.history-card {
    background: #f9f9f9;
    border-radius: 12px;
    overflow: hidden;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
    transition: transform 0.2s, box-shadow 0.2s;
}

.history-card:hover {
    transform: translateY(-4px);
    box-shadow: 0 8px 20px rgba(0, 0, 0, 0.15);
}

.card-image {
    width: 100%;
    height: 200px;
    overflow: hidden;
    background: #eee;
}

.card-image img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.card-info {
    padding: 15px;
}

.card-time {
    font-size: 0.9em;
    color: #666;
    margin-bottom: 5px;
}

.card-desc {
    font-size: 1em;
    color: #333;
    margin-top: 8px;
}

.card-actions {
    padding: 15px;
    display: flex;
    gap: 10px;
    border-top: 1px solid #eee;
}

.btn-view,
.btn-delete {
    flex: 1;
    padding: 10px;
    border: none;
    border-radius: 6px;
    font-size: 0.95em;
    cursor: pointer;
    text-decoration: none;
    text-align: center;
    transition: all 0.2s;
}

.btn-view {
    background: #667eea;
    color: white;
}

.btn-view:hover {
    background: #5568d3;
}

.btn-delete {
    background: #f44336;
    color: white;
}

.btn-delete:hover {
    background: #d32f2f;
}

.empty-state {
    text-align: center;
    padding: 60px 20px;
    color: #999;
    font-size: 1.1em;
}

/* 展示页面样式 */
.display-container {
    text-align: center;
    padding: 20px;
}

.display-container h1 {
    color: #667eea;
    margin-bottom: 20px;
}

.canvas-container {
    position: relative;
    display: inline-block;
    margin: 20px auto;
    border-radius: 12px;
    overflow: hidden;
    box-shadow: 0 8px 30px rgba(0, 0, 0, 0.3);
}

#displayCanvas {
    display: block;
    max-width: 100%;
    height: auto;
}

.video-container {
    position: relative;
    display: inline-block;
}

#videoElement {
    display: none;
}

.controls {
    margin-top: 20px;
}

.btn-back {
    padding: 12px 30px;
    background: #667eea;
    color: white;
    border: none;
    border-radius: 8px;
    font-size: 1em;
    cursor: pointer;
    text-decoration: none;
    display: inline-block;
    transition: background 0.2s;
}

.btn-back:hover {
    background: #5568d3;
}

.status-message {
    margin-top: 15px;
    padding: 12px;
    border-radius: 8px;
    display: none;
}

.status-message.info {
    background: #e3f2fd;
    color: #1976d2;
    border-left: 4px solid #1976d2;
}

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

/* 响应式设计 */
@media (max-width: 768px) {
    .container {
        padding: 20px;
    }

    header h1 {
        font-size: 2em;
    }

    .history-grid {
        grid-template-columns: 1fr;
    }

    .card-actions {
        flex-direction: column;
    }
}