.tool-container{max-width:960px;margin:0 auto;padding:30px 20px;}
.calc-box{background:#fff;border-radius:16px;padding:25px 30px;}
.group-title{font-size:16px;font-weight:600;color:#2d6ff7;margin:25px 0 15px;padding-bottom:8px;border-bottom:1px solid #eee;}
.fast-box{background:#f0f6ff;padding:20px;border-radius:12px;margin-bottom:25px;}
.fast-title{font-weight:600;margin-bottom:15px;color:#222;}
.btn-fast{padding:5px 10px;font-size:13px;border:none;border-radius:4px;background:#fff;color:#333;border:1px solid #ccc;margin:0 6px 6px 0;cursor:pointer;}
.btn-fast.active{background:#2d6ff7;color:#fff;border-color:#2d6ff7;}
.btn-grade{padding:5px 10px;font-size:13px;border:1px solid #ccc;background:#fff;color:#333;border-radius:4px;margin:0 6px 6px 0;cursor:pointer;}
.btn-grade.active{background:#2d6ff7;color:#fff;border-color:#2d6ff7;}
.item-row{display:flex;flex-wrap:wrap;gap:15px;margin-bottom:18px;align-items:center;}
.item-item{flex:1;min-width:220px;}
.item-item label{display:block;margin-bottom:6px;color:#333;font-size:14px;}
.item-item input{width:100%;height:42px;padding:0 12px;border:1px solid #ddd;border-radius:8px;outline:none;font-size:14px;}
.btn-wrap{display:flex;gap:15px;margin-top:10px;}
.btn-submit{background:#2d6ff7;color:#fff;border:none;padding:12px 30px;border-radius:8px;font-size:15px;cursor:pointer;}
.btn-submit:hover{background:#255ed9;}
.btn-reset{background:#f5f7fa;color:#666;border:none;padding:12px 30px;border-radius:8px;font-size:15px;cursor:pointer;}
.result-box{margin-top:25px;padding:22px;background:#f8faff;border-radius:10px;display:none;}
.result-item{font-size:15px;margin:12px 0;color:#333;}
.result-item strong{color:#2d6ff7;font-size:16px;}
.result-h{font-size:17px;font-weight:600;margin:15px 0 5px;color:#111;}
.tip-text{font-size:13px;color:#888;margin-top:12px;line-height:1.7;}
.copy-btn{margin-top:15px;padding:8px 16px;border:none;border-radius:6px;background:#e8f0fe;color:#2d6ff7;cursor:pointer;}