.ytb-pct-header {
    background: #8B5CF6;
    color: #fff;
    font-size: 22px;
    font-weight: 700;
    padding: 16px 20px;
    border-radius: 8px 8px 0 0;
}

.ytb-pct-card {
    background: #fff;
    border: 1px solid #E0E0E0;
    border-top: none;
    border-radius: 0 0 8px 8px;
    padding: 20px;
    box-shadow: 0 2px 6px rgba(0,0,0,0.06);
    margin-bottom: 8px;
}

.ytb-pct-tabs {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
    margin-bottom: 20px;
}
.ytb-pct-tab {
    flex: 1;
    min-width: 140px;
    padding: 10px 8px;
    border: 1.5px solid #E0E0E0;
    background: #FAFAFA;
    border-radius: 6px;
    font-size: 12.5px;
    font-weight: 600;
    color: #616161;
    cursor: pointer;
}
.ytb-pct-tab.is-active {
    border-color: #8B5CF6;
    background: #F5F3FF;
    color: #7C3AED;
}

.ytb-pct-fields {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(140px, 1fr));
    gap: 14px;
    margin-bottom: 8px;
}
.ytb-pct-field label {
    display: block;
    font-size: 13px;
    color: #424242;
    margin-bottom: 6px;
}
.ytb-pct-field input {
    width: 100%;
    padding: 10px 12px;
    border: 1px solid #CFD8DC;
    border-radius: 6px;
    font-size: 14px;
    box-sizing: border-box;
}

.ytb-pct-example {
    font-size: 12.5px;
    color: #9E9E9E;
    margin: 0 0 6px;
    font-style: italic;
}

.ytb-pct-btn {
    width: 100%;
    background: #8B5CF6;
    color: #fff;
    border: none;
    padding: 12px;
    border-radius: 6px;
    font-size: 15px;
    font-weight: 700;
    cursor: pointer;
    margin-top: 10px;
}
.ytb-pct-btn:hover { background: #7C3AED; }

.ytb-pct-result {
    margin-top: 22px;
    padding-top: 18px;
    border-top: 1px solid #EEE;
    text-align: center;
}
.ytb-pct-result-value {
    font-size: 36px;
    font-weight: 800;
    color: #7C3AED;
    margin-bottom: 8px;
}
.ytb-pct-result-formula {
    font-size: 13.5px;
    color: #757575;
}

@media (max-width: 480px) {
    .ytb-pct-fields { grid-template-columns: 1fr; }
    .ytb-pct-tab { min-width: 100%; }
}