:root {
    --primary-color: #6c5ce7;
    --secondary-color: #5649d6;
    --light-bg: #f8f9ff;
    --dark-text: #2d3436;
    --border-color: #dfe6e9;
    --accent-color: #00cec9;
    --shadow-sm: 0 1px 3px rgba(0,0,0,0.12);
    --shadow-md: 0 4px 6px rgba(0,0,0,0.1);
    --transition: all 0.3s cubic-bezier(0.25, 0.8, 0.25, 1);
}

html, body {
    margin: 0;
    padding: 0;
    width: 100%;
    height: 100%;
    overflow: hidden;
    font-family: 'Segoe UI', system-ui, sans-serif;
    background-color: var(--light-bg);
    color: var(--dark-text);
}

.container {
    display: flex;
    height: 100vh;
    padding: 20px;
    box-sizing: border-box;
    gap: 20px;
}

.word-bank {
    width: 300px;
    background: white;
    border-radius: 16px;
    box-shadow: var(--shadow-md);
    display: flex;
    flex-direction: column;
    overflow: hidden;
    transition: var(--transition);
    border: 1px solid rgba(0,0,0,0.05);
}

.search-box {
    padding: 20px;
    background: transparent;
    box-sizing: border-box;
}

.search-box-container {
    position: relative;
    width: calc(100% - 40px);
    margin: 0 auto;
}

.search-box input {
    width: 100%;
    padding: 12px 45px 12px 15px;
    border: 1px solid var(--border-color);
    border-radius: 20px;
    font-size: 14px;
    background: white;
    transition: all 0.3s ease;
    box-shadow: none;
    box-sizing: border-box;
}

.search-box input:focus {
    outline: none;
    border-color: var(--accent-color);
    box-shadow: 0 0 0 3px rgba(0,206,201,0.1);
}

.search-icon {
    position: absolute;
    right: 15px;
    top: 50%;
    transform: translateY(-50%);
    color: var(--accent-color);
    pointer-events: none;
}

.word-list {
    flex: 1;
    padding: 15px;
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 12px;
    overflow-y: auto;
}

.word-thumb {
    background: white;
    border-radius: 12px;
    padding: 12px;
    cursor: pointer;
    transition: var(--transition);
    text-align: center;
    box-shadow: var(--shadow-sm);
    border: 1px solid rgba(0,0,0,0.03);
    background: linear-gradient(135deg, #f5f7fa 0%, #ffffff 100%);
    position: relative;
    overflow: hidden;
}

.word-thumb:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 8px rgba(0,0,0,0.1);
}

.word-thumb img {
    max-width: 100%;
    height: 60px;
    object-fit: contain;
    transition: opacity 0.3s ease;
    opacity: 0;
}

.word-thumb img.loaded {
    opacity: 1;
}

/* 加载动画 */
@keyframes shimmer {
    0% { background-position: -468px 0 }
    100% { background-position: 468px 0 }
}

.word-thumb .loading-placeholder {
    position: absolute;
    top: 12px;
    left: 12px;
    right: 12px;
    height: 60px;
    background: linear-gradient(to right, #f6f7f8 0%, #edeef1 20%, #f6f7f8 40%, #f6f7f8 100%);
    background-size: 800px 104px;
    animation: shimmer 1.5s infinite linear;
    border-radius: 4px;
}

.canvas-container {
    flex: 1;
    display: flex;
    flex-direction: column;
    height: 100%;
    position: relative;
    padding: 0;
    margin: 0;
}

.canvas-wrapper {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: white;
    padding: 0;
    margin: 0;
    border-radius: 12px;
    box-shadow: 0 4px 20px rgba(0,0,0,0.08);
    transition: all 0.3s ease;
    border: 1px solid rgba(0,0,0,0.05);
}

.canvas-wrapper:hover {
    box-shadow: 0 8px 25px rgba(0,0,0,0.12);
    transform: translateY(-1px);
}

#canvas {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    display: block;
    background: white;
}

.button-group {
    position: absolute;
    bottom: 20px;
    right: 20px;
    z-index: 10;
    display: flex;
    gap: 10px;
}

.export-btn {
    align-self: flex-end;
    background: var(--primary-color);
    color: white;
    border: none;
    padding: 12px 24px;
    border-radius: 8px;
    cursor: pointer;
    font-weight: 600;
    transition: var(--transition);
    box-shadow: var(--shadow-sm);
    text-transform: uppercase;
    letter-spacing: 0.5px;
    margin: 20px;
}

.export-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 7px 14px rgba(0,0,0,0.1);
}

.export-btn:hover {
    background: var(--secondary-color);
}