.ahn-container {
    max-width: 850px;
    margin: 40px auto;
    font-family: 'Inter', -apple-system, sans-serif;
}

.ahn-main-card {
    background: #fff;
    border: 1px solid #e2e8f0;
    border-radius: 20px;
    padding: 40px;
    box-shadow: 0 10px 25px rgba(0,0,0,0.05);
}

.ahn-title { font-size: 26px; font-weight: 800; margin: 0; letter-spacing: -0.02em; }
.ahn-subtitle-meta { color: #64748b; font-size: 14px; margin: 5px 0 30px; }

.ahn-row { display: grid; grid-template-columns: 1fr 1fr; gap: 20px; margin-bottom: 10px; }
@media (max-width: 600px) { .ahn-row { grid-template-columns: 1fr; } .ahn-main-card { padding: 25px; } }

.ahn-field { margin-bottom: 20px; position: relative; }
.ahn-field label { display: block; font-size: 13px; font-weight: 700; margin-bottom: 8px; color: #1e293b; }
.ahn-field input, .ahn-field select {
    width: 100%; height: 48px; border: 2px solid #f1f5f9; background: #f8fafc;
    border-radius: 10px; padding: 0 15px; font-size: 15px; transition: 0.2s; box-sizing: border-box;
}
.ahn-field input:focus { border-color: #2563eb; background: #fff; outline: none; }

/* Validation UI */
input.invalid { border-color: #ef4444 !important; background: #fffafa !important; }
.error-msg { color: #ef4444; font-size: 11px; font-weight: 600; display: none; margin-top: 4px; }

/* Bottom Summary */
.ahn-summary-section {
    background: #f1f5f9;
    padding: 25px;
    border-radius: 14px;
    margin: 30px 0;
}
.ahn-summary-grid { display: flex; justify-content: space-between; align-items: center; flex-wrap: wrap; gap: 15px; }
.sum-row { font-size: 14px; margin-bottom: 5px; color: #475569; }

.price-line.total { font-size: 13px; color: #64748b; text-align: right; }
.price-line.payable { font-size: 24px; font-weight: 900; color: #2563eb; text-align: right; }

/* Action Footer */
.ahn-check { display: flex; align-items: center; gap: 10px; cursor: pointer; font-size: 14px; margin: 20px 0; }
.ahn-check input { width: 18px; height: 18px; accent-color: #2563eb; }
.ahn-btn {
    width: 100%; height: 60px; background: #2563eb; color: #fff; border: none;
    border-radius: 12px; font-size: 18px; font-weight: 700; cursor: pointer; transition: 0.3s;
}
.ahn-btn:hover { background: #1d4ed8; transform: translateY(-2px); box-shadow: 0 8px 15px rgba(37,99,235,0.3); }
.ahn-redirect-note { text-align: center; font-size: 12px; color: #94a3b8; margin-top: 15px; }

/* Payment Plan Selector Styling */
.ahn-pay-selector {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 15px;
    margin-top: 5px;
}

.ahn-pay-card {
    cursor: pointer;
    position: relative;
}

.ahn-pay-card input {
    position: absolute;
    opacity: 0;
    width: 0;
    height: 0;
}

.ahn-pay-content {
    border: 2px solid #f1f5f9;
    background: #f8fafc;
    padding: 15px;
    border-radius: 12px;
    text-align: center;
    transition: all 0.2s ease;
    display: flex;
    flex-direction: column;
}

.ahn-pay-card input:checked + .ahn-pay-content {
    border-color: #2563eb;
    background: #eff6ff;
    box-shadow: 0 4px 12px rgba(37, 99, 235, 0.1);
}

.pay-title {
    display: block;
    font-weight: 800;
    font-size: 14px;
    color: #1e293b;
}

.pay-desc {
    font-size: 11px;
    color: #64748b;
    margin-top: 2px;
}

.ahn-pay-card input:checked + .ahn-pay-content .pay-title {
    color: #2563eb;
}

@media (max-width: 500px) {
    .ahn-pay-selector { grid-template-columns: 1fr; }
}

/* Red Highlight for Invalid Fields */
input.invalid {
    border-color: #ef4444 !important;
    background-color: #fff8f8 !important;
}