/* === 基础变量 (局部化) === */
#translate-tool-root {
    --trans-primary: #49b1f5;
    --trans-glass-bg: rgba(255, 255, 255, 0.7);
    --trans-glass-border: 1px solid rgba(255, 255, 255, 0.6);
    --trans-shadow: 0 8px 32px 0 rgba(31, 38, 135, 0.15);
    --trans-text: #333;
    --trans-radius: 12px;
    --bg-color: #fff;
    --panel-bg: #f8f9fa;
    
    max-width: 1000px;
    margin: 0 auto;
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
    padding: 20px;
    background: var(--bg-color);
    border-radius: 12px;
    box-shadow: 0 4px 24px rgba(0,0,0,0.05);
    box-sizing: border-box;
}

[data-theme="dark"] #translate-tool-root {
    --trans-glass-bg: rgba(30, 30, 30, 0.6);
    --trans-glass-border: 1px solid rgba(255, 255, 255, 0.1);
    --trans-text: #e0e0e0;
    --trans-primary: #52a7e0;
    --bg-color: #1e1e1e;
    --panel-bg: #2d2d2d;
}

/* === 头部布局 === */
#translate-tool-root .trans-header {
    display: flex;
    justify-content: center;
    align-items: center;
    gap: 15px;
    margin-bottom: 20px;
    padding: 15px;
    background: var(--trans-glass-bg);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    border-radius: var(--trans-radius);
    border: var(--trans-glass-border);
    box-shadow: var(--trans-shadow);
}

#translate-tool-root .trans-select {
    padding: 8px 12px;
    border-radius: 8px;
    border: 1px solid rgba(128, 128, 128, 0.3);
    background: rgba(255, 255, 255, 0.5);
    color: var(--trans-text);
    font-size: 15px;
    outline: none;
    cursor: pointer;
    transition: all 0.3s;
    width: 140px; 
    text-align: center;
    text-align-last: center; 
}

[data-theme="dark"] #translate-tool-root .trans-select {
    background: rgba(0, 0, 0, 0.3);
}

[data-theme="dark"] #translate-tool-root .trans-select option {
    background: #333;
}

#translate-tool-root .trans-swap-btn {
    width: 36px;
    height: 36px;
    border-radius: 50%;
    border: 1px solid rgba(128, 128, 128, 0.2);
    background: rgba(255, 255, 255, 0.5);
    color: var(--trans-primary);
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all 0.3s;
    font-size: 18px;
    flex-shrink: 0;
}

[data-theme="dark"] #translate-tool-root .trans-swap-btn {
    background: rgba(255, 255, 255, 0.1);
}

#translate-tool-root .trans-swap-btn:hover {
    transform: rotate(180deg);
    background: var(--trans-primary);
    color: white;
}

/* === 主体与输入框 === */
#translate-tool-root .trans-body { display: flex; gap: 20px; min-height: 350px; }
#translate-tool-root .trans-box { flex: 1; display: flex; flex-direction: column; background: var(--trans-glass-bg); backdrop-filter: blur(10px); -webkit-backdrop-filter: blur(10px); border-radius: var(--trans-radius); border: var(--trans-glass-border); box-shadow: var(--trans-shadow); position: relative; transition: transform 0.2s; }
#translate-tool-root .trans-box:focus-within { border-color: var(--trans-primary); }
#translate-tool-root .trans-textarea { flex: 1; width: 100%; padding: 20px; border: none; background: transparent; resize: none; outline: none; font-size: 16px; line-height: 1.6; color: var(--trans-text); box-sizing: border-box; }
#translate-tool-root .trans-tools { padding: 10px 15px; display: flex; justify-content: space-between; align-items: center; border-top: 1px solid rgba(128, 128, 128, 0.1); }
#translate-tool-root .trans-btn-icon { display: flex; align-items: center; gap: 5px; padding: 6px 12px; border-radius: 6px; cursor: pointer; font-size: 13px; color: #888; transition: all 0.2s; background: transparent; border: none; }
#translate-tool-root .trans-btn-icon:hover { background: rgba(128, 128, 128, 0.1); color: var(--trans-primary); }
#translate-tool-root .trans-btn-icon.copied { background: #67c23a; color: white; }

/* === 底部按钮 === */
#translate-tool-root .trans-action { margin-top: 25px; text-align: center; }
#translate-tool-root .trans-btn-main { background: var(--trans-primary); color: white; border: none; padding: 12px 60px; border-radius: 30px; font-size: 18px; font-weight: 600; cursor: pointer; box-shadow: 0 4px 15px rgba(73, 177, 245, 0.4); transition: all 0.3s; }
#translate-tool-root .trans-btn-main:hover { transform: translateY(-2px); box-shadow: 0 6px 20px rgba(73, 177, 245, 0.6); }
#translate-tool-root .trans-btn-main:disabled { background: #ccc; cursor: not-allowed; transform: none; box-shadow: none; }

/* ============================================================
   移动端响应式布局适配
============================================================ */
@media (max-width: 768px) {
    #translate-tool-root .trans-body { flex-direction: column; }
    #translate-tool-root .trans-box { min-height: 200px; }
}

@media (max-width: 500px) {
    /* 使用 Grid 布局剥离 DOM 顺序，实现“左侧按钮、右侧上下框” */
    #translate-tool-root .trans-header {
        display: grid;
        grid-template-columns: auto 1fr; /* 左侧自适应按钮宽度，右侧占据剩余全部空间 */
        grid-template-rows: auto auto;   /* 上下两行 */
        gap: 12px 15px;                  /* 行间距 12px，列间距 15px */
        padding: 15px;
    }
    
    /* 强制源语言框在：第2列，第1行 */
    #translate-tool-root #tr-srcLang {
        grid-column: 2;
        grid-row: 1;
        width: 100%; 
    }
    
    /* 强制目标语言框在：第2列，第2行 */
    #translate-tool-root #tr-tgtLang {
        grid-column: 2;
        grid-row: 2;
        width: 100%;
    }

    /* 强制按钮在：第1列，跨越第1和第2行，并居中对齐 */
    #translate-tool-root .trans-swap-btn {
        grid-column: 1;
        grid-row: 1 / span 2;
        align-self: center;   /* 垂直居中 */
        justify-self: center; /* 水平居中 */
        transform: rotate(90deg); /* 顺时针旋转，箭头指向上和下 */
    }
    
    /* 悬浮动效 */
    #translate-tool-root .trans-swap-btn:hover {
        transform: rotate(270deg);
    }
}