.pog-calculator {
    max-width: 500px;
    margin: 20px auto;
    padding: 20px;
    border: 1px solid #e5e5e5;
    border-radius: 4px;
    background: linear-gradient(135deg, #f5f5f5, #ffffff);
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.1);
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen-Sans, Ubuntu, Cantarell, 'Helvetica Neue', sans-serif;
    color: #333;
}
.calculator-heading {
    color: #005177;
    text-align: center;
    margin-bottom: 20px;
    font-size: 1.8em;
    font-weight: 800;
    padding: 10px;
    background: linear-gradient(135deg, rgba(0, 115, 170, 0.1), rgba(0, 115, 170, 0.05));
    border-radius: 4px;
    box-shadow: 0 0 10px rgba(0, 115, 170, 0.3);
    animation: headingFadeIn 0.8s ease-in-out;
}
@keyframes headingFadeIn {
    from { opacity: 0; transform: scale(0.95); }
    to { opacity: 1; transform: scale(1); }
}
.pog-calculator h4 {
    color: #0073aa;
    margin: 15px 0 10px;
    font-size: 1.1em;
}
.pog-calculator label {
    display: block;
    margin: 10px 0 5px;
    color: #444;
    font-weight: 600;
    cursor: help;
}
.pog-calculator input {
    width: 100%;
    padding: 8px 12px;
    margin-bottom: 10px;
    border: 1px solid #ddd;
    border-radius: 4px;
    background: #fff;
    color: #333;
    transition: border-color 0.3s, box-shadow 0.3s, transform 0.2s;
}
.pog-calculator input:focus {
    border-color: #0073aa;
    outline: none;
    box-shadow: 0 0 5px rgba(0, 115, 170, 0.3);
    transform: scale(1.01);
}
.ultrasound-inputs {
    display: flex;
    gap: 10px;
}
.ultrasound-inputs input {
    width: 50%;
}
.button-container {
    display: flex;
    justify-content: flex-end;
    padding: 2px 0;
    background: #f9f9f9;
    background: linear-gradient(135deg, rgba(0, 0, 0, 0.05), #f9f9f9);
}
.pog-calculator button {
    padding: 10px 20px;
    border: none;
    border-radius: 4px;
    cursor: pointer;
    font-size: 1em;
    font-weight: 600;
    background: linear-gradient(135deg, #0073aa, #005177);
    color: #fff;
    box-shadow: 0 0 12px rgba(0, 115, 170, 0.4);
    transition: all 0.3s ease;
}
.pog-calculator button:hover {
    background: linear-gradient(135deg, #0073aa, #005177);
    box-shadow: 0 0 12px rgba(0, 115, 170, 0.4);
}
.pog-calculator p {
    margin: 5px 0;
    color: #444;
    line-height: 1.5;
}
.disclaimer {
    font-size: 0.85em;
    color: #666;
    margin-top: 10px;
}
.pog-calculator progress {
    width: 100%;
    height: 6px;
    margin: 5px 0;
    border-radius: 3px;
    background: #e5e5e5;
}
.results {
    padding: 10px;
    background: #fff;
    border: 1px solid #e5e5e5;
    border-radius: 4px;
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.1);
    margin-top: 15px;
    opacity: 0;
}
.results.fade-in {
    animation: fadeIn 0.5s forwards;
    opacity: 1;
}
@keyframes fadeIn {
    from { opacity: 0; }
    to { opacity: 1; }
}
.milestone-timeline {
    margin-top: 15px;
}
.timeline {
    display: flex;
    justify-content: space-between;
    position: relative;
    margin: 10px 0;
}
.timeline::before {
    content: '';
    position: absolute;
    top: 10px;
    left: 0;
    right: 0;
    height: 2px;
    background: #e5e5e5;
}
.milestone {
    text-align: center;
    width: 16%;
}
.milestone .week {
    display: block;
    font-size: 0.85em;
    color: #666;
    font-weight: 500;
}
.milestone .text {
    display: block;
    font-size: 0.75em;
    color: #666;
    margin-top: 3px;
}
.milestone.active .week, .milestone.active .text {
    color: #0073aa;
    font-weight: 600;
}
.milestone.active::before {
    content: '';
    display: block;
    width: 6px;
    height: 6px;
    background: #0073aa;
    border-radius: 50%;
    margin: 6px auto;
}
@media (max-width: 600px) {
    .pog-calculator {
        padding: 15px;
        margin: 10px;
    }
    .ultrasound-inputs {
        flex-direction: column;
    }
    .ultrasound-inputs input {
        width: 100%;
    }
    .button-container {
        justify-content: center;
    }
}