.txt-m3u-converter {
    font-family: "Segoe UI", "Microsoft YaHei", sans-serif;
    background: #f4f5f7;
    padding: 20px;
}
.txt-m3u-converter .converter-container {
    max-width: 1100px;
    margin: 0 auto;
    background: #fff;
    padding: 20px 30px;
    border-radius: 10px;
    box-shadow: 0 10px 30px rgba(0,0,0,0.08);
}
.txt-m3u-converter textarea {
    width: 100%;
    min-height: 180px;
    border-radius: 6px;
    border: 1px solid #dfe1e6;
    padding: 12px;
    resize: vertical;
}
.txt-m3u-converter .tabs {
    display: flex;
    gap: 10px;
    margin-bottom: 20px;
}
.txt-m3u-converter .tab-btn {
    flex: 1;
    padding: 12px;
    border: none;
    border-radius: 6px;
    background: #e9ecef;
    cursor: pointer;
    font-weight: 600;
}
.txt-m3u-converter .tab-btn.active {
    background: #1da1f2;
    color: #fff;
}
.txt-m3u-converter .panel {
    margin-bottom: 30px;
    border: 1px solid #e1e5ea;
    padding: 20px;
    border-radius: 8px;
}
.txt-m3u-converter .options,
.txt-m3u-converter .actions {
    display: flex;
    gap: 15px;
    flex-wrap: wrap;
    margin: 15px 0;
}
.txt-m3u-converter .actions button {
    padding: 10px 18px;
    border: none;
    border-radius: 6px;
    background: #1da1f2;
    color: #fff;
    cursor: pointer;
}
.txt-m3u-converter .actions button.secondary {
    background: #6c757d;
}
.txt-m3u-converter .actions button.danger {
    background: #dc3545;
}
.txt-m3u-converter .summary {
    background: #f1f5f9;
    border-radius: 6px;
    padding: 10px;
    white-space: pre-wrap;
    min-height: 80px;
    border: 1px solid #e2e8f0;
}
.txt-m3u-converter .split {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
    gap: 20px;
}
.txt-m3u-converter .tab-panel {
    display: none;
}
.txt-m3u-converter .tab-panel.active {
    display: block;
}