/* ========================================
   单位换算工具样式
   ======================================== */

/* 主内容 */
.main-content { 
    width: 100%; 
    max-width: 900px;
    height: calc(100vh - 120px); 
    display: flex; 
    align-items: center; 
    padding: 0 20px; 
    padding-bottom: 50px; 
    z-index: 10; 
}
.container { width: 100%; height: 100%; }
.tool-card { 
    background: var(--bg-card); 
    border: 1px solid var(--border-color); 
    border-radius: var(--radius-xl); 
    overflow: hidden; 
    display: flex; 
    flex-direction: column; 
    width: 100%;
    height: 100%;
    box-shadow: 0 20px 40px rgba(0, 0, 0, 0.3);
}

/* 分类标签栏 */
.settings-bar {
    background: rgba(0,0,0,0.2);
    border-bottom: 1px solid var(--border-color);
    padding: 8px 16px;
    display: flex;
    justify-content: center;
    flex-shrink: 0;
}
.category-tabs { display: flex; gap: 8px; }
.tab-btn {
    background: rgba(255,255,255,0.05);
    border: 1px solid var(--border-color);
    color: var(--text-secondary);
    padding: 8px 16px;
    border-radius: 20px;
    cursor: pointer;
    font-size: 13px;
    transition: 0.2s;
    display: flex; align-items: center; gap: 6px;
}
.tab-btn:hover { background: rgba(255,255,255,0.1); }
.tab-btn.active { background: var(--primary-color); color: white; border-color: var(--primary-color); }

/* 转换器主体 */
.converter-body {
    flex: 1;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 30px 20px;
}
.converter-group {
    display: flex;
    align-items: center;
    gap: 20px;
    width: 100%;
    max-width: 800px;
}
.input-panel, .output-panel {
    flex: 1;
    display: flex;
    flex-direction: column;
    gap: 10px;
}
.group-label { font-size: 12px; color: var(--text-muted); font-weight: 600; }

input[type="number"] {
    background: rgba(255,255,255,0.05);
    border: 1px solid var(--border-color);
    padding: 16px;
    font-size: 32px;
    color: var(--text-primary);
    font-weight: 600;
    border-radius: 12px;
    outline: none;
    font-family: var(--font-mono);
    width: 100%;
}
input[type="number"]:focus { border-color: var(--primary-color); }

.unit-select {
    background: rgba(255,255,255,0.05);
    border: 1px solid var(--border-color);
    padding: 12px;
    color: var(--text-primary);
    border-radius: 8px;
    font-size: 14px;
    outline: none;
    cursor: pointer;
}
.unit-select:focus { border-color: var(--primary-color); }

/* 交换按钮 */
.swap-container { display: flex; flex-direction: column; align-items: center; justify-content: center; padding-top: 20px; }
.btn-swap {
    width: 50px; height: 50px;
    background: rgba(255,255,255,0.05);
    border: 1px solid var(--border-color);
    border-radius: 50%;
    color: var(--text-secondary);
    cursor: pointer;
    transition: 0.2s;
    display: flex; align-items: center; justify-content: center;
    font-size: 16px;
}
.btn-swap:hover { background: var(--primary-color); color: white; border-color: var(--primary-color); transform: rotate(90deg); }

/* 公式条 */
.formula-bar {
    background: rgba(0,0,0,0.1);
    border-top: 1px solid var(--border-color);
    padding: 12px 20px;
    text-align: center;
    flex-shrink: 0;
}
.formula-content {
    color: var(--text-muted);
    font-size: 14px;
    font-family: var(--font-mono);
}
.formula-content span { color: var(--primary-color); }

/* 响应式 */
@media (max-width: 768px) {
    .converter-group { flex-direction: column; gap: 15px; }
    .swap-container { padding-top: 0; transform: rotate(90deg); }
    .btn-swap:hover { transform: rotate(180deg); }
}