.npb-calc {
    --npb-accent: #3f9baa;
    --npb-accent-dark: #2d7280;
    --npb-blue-soft: #a8cee8;
    --npb-green-soft: #c7e4b5;
    --npb-line: #cbd9dd;
    --npb-text: #34444a;
    --npb-muted: #6c7c82;
    box-sizing: border-box;
    width: 100%;
    max-width: 1180px;
    margin: 28px auto;
    color: var(--npb-text);
    font-family: Roboto, Arial, sans-serif;
    font-size: 15px;
    line-height: 1.45;
}
.npb-calc *, .npb-calc *::before, .npb-calc *::after { box-sizing: inherit; }
.npb-calc__hero {
    display: flex;
    gap: 18px;
    align-items: center;
    padding: 24px 28px;
    color: #fff;
    background: linear-gradient(135deg, var(--npb-accent), #4fa8b5);
    border-radius: 8px 8px 0 0;
}
.npb-calc__hero h2 {
    margin: 0 0 6px;
    color: #fff;
    font-family: Georgia, "Times New Roman", serif;
    font-size: clamp(25px, 3vw, 39px);
    font-weight: 400;
    letter-spacing: .035em;
    text-transform: uppercase;
}
.npb-calc__intro, .npb-calc__intro p { margin: 0; color: rgba(255,255,255,.88); }
.npb-calc__reticle {
    position: relative;
    flex: 0 0 58px;
    width: 58px;
    height: 58px;
    border: 2px solid rgba(255,255,255,.85);
    border-radius: 50%;
}
.npb-calc__reticle::before, .npb-calc__reticle::after {
    position: absolute;
    content: "";
    background: rgba(255,255,255,.85);
}
.npb-calc__reticle::before { top: 27px; left: -7px; width: 68px; height: 2px; }
.npb-calc__reticle::after { top: -7px; left: 27px; width: 2px; height: 68px; }
.npb-calc__notice {
    padding: 12px 18px;
    color: #385142;
    background: var(--npb-green-soft);
    border-right: 1px solid #b5d29f;
    border-left: 1px solid #b5d29f;
}
.npb-calc__form {
    padding: 20px;
    background: #f7fafb;
    border-right: 1px solid var(--npb-line);
    border-left: 1px solid var(--npb-line);
}
.npb-primary {
    overflow: hidden;
    background: #fff;
    border: 1px solid var(--npb-line);
    border-radius: 7px;
}
.npb-primary__title {
    padding: 11px 16px;
    color: #fff;
    font-weight: 700;
    letter-spacing: .02em;
    background: var(--npb-accent-dark);
}
.npb-primary__grid {
    display: grid;
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 0;
}
.npb-control {
    display: flex;
    min-width: 0;
    flex-direction: column;
    gap: 7px;
    padding: 14px 16px;
    background: #fff;
    border-right: 1px solid #e0e8eb;
    border-bottom: 1px solid #e0e8eb;
}
.npb-control--hot { background: linear-gradient(180deg, #fff, #f8fcfd); }
.npb-control--wide { grid-column: span 3; }
.npb-control > span { color: #324f58; font-weight: 700; }
.npb-control small { color: var(--npb-muted); font-size: 12px; }
.npb-control input, .npb-control select, .npb-row input, .npb-row select {
    width: 100%;
    min-height: 40px;
    padding: 8px 10px;
    color: #2e3f45;
    font: inherit;
    background: #fff;
    border: 1px solid #b9cbd1;
    border-radius: 4px;
    outline: none;
}
.npb-control input:focus, .npb-control select:focus, .npb-row input:focus, .npb-row select:focus {
    border-color: var(--npb-accent);
    box-shadow: 0 0 0 2px rgba(63,155,170,.14);
}
.npb-input-line { display: grid; grid-template-columns: minmax(0, 1fr) 94px; gap: 8px; align-items: center; }
.npb-input-line--brand { grid-template-columns: 1fr 1.2fr; }
.npb-prefix { display: none; }
.npb-sections {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 16px;
    margin-top: 18px;
}
.npb-box {
    min-width: 0;
    margin: 0;
    padding: 16px;
    background: #fff;
    border: 1px solid var(--npb-line);
    border-radius: 7px;
}
.npb-box legend {
    padding: 0 8px;
    color: var(--npb-accent-dark);
    font-weight: 700;
}
.npb-box--full { grid-column: 1 / -1; }
.npb-box-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 12px 18px; }
.npb-row {
    display: grid;
    grid-template-columns: minmax(170px, 1fr) minmax(110px, 160px);
    gap: 14px;
    align-items: center;
    margin-bottom: 10px;
}
.npb-row:last-child { margin-bottom: 0; }
.npb-row > span { color: #43585f; }
.npb-actions {
    display: flex;
    gap: 10px;
    margin-top: 18px;
}
.npb-button {
    min-height: 45px;
    padding: 10px 18px;
    color: #35515a;
    font: inherit;
    font-weight: 700;
    cursor: pointer;
    background: #fff;
    border: 1px solid #b8cbd0;
    border-radius: 4px;
}
.npb-button--primary {
    flex: 1 1 auto;
    color: #fff;
    background: var(--npb-accent);
    border-color: var(--npb-accent);
}
.npb-button:hover { filter: brightness(.97); }
.npb-results {
    padding: 20px;
    background: #fff;
    border: 1px solid var(--npb-line);
    border-top: 7px solid var(--npb-blue-soft);
    border-radius: 0 0 8px 8px;
    box-shadow: 0 12px 28px rgba(48,85,96,.09);
}
.npb-results__head {
    display: flex;
    gap: 18px;
    align-items: center;
    justify-content: space-between;
    margin-bottom: 16px;
}
.npb-results__head span { color: var(--npb-muted); font-size: 12px; text-transform: uppercase; letter-spacing: .08em; }
.npb-results__head h3 { margin: 3px 0 0; color: #3f6b78; font-family: Georgia, "Times New Roman", serif; font-size: 23px; font-weight: 400; }
.npb-chip { padding: 7px 11px; color: #2e6370; font-weight: 700; background: #e8f3f6; border: 1px solid #c7dfe4; border-radius: 999px; }
.npb-metrics { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 12px; }
.npb-metric { padding: 14px; background: #f8fbfc; border: 1px solid #d8e4e7; border-radius: 6px; }
.npb-metric span { display: block; min-height: 34px; color: var(--npb-muted); font-size: 12px; }
.npb-metric strong { display: block; margin: 5px 0 10px; color: #325d68; font-size: 17px; }
.npb-meter { height: 7px; overflow: hidden; background: #dce8eb; border-radius: 999px; }
.npb-meter i { display: block; width: 50%; height: 100%; background: linear-gradient(90deg, var(--npb-accent), #81bd84); transition: width .25s ease; }
.npb-chart-wrap { margin-top: 14px; padding: 10px; background: #fbfdfe; border: 1px solid #d8e4e7; border-radius: 6px; }
.npb-chart-wrap canvas { display: block; width: 100%; height: 310px; }
.npb-summary { margin: 14px 0 0; color: #536a72; }
@media (max-width: 900px) {
    .npb-primary__grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
    .npb-control--wide { grid-column: span 2; }
    .npb-metrics { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}
@media (max-width: 680px) {
    .npb-calc { margin: 16px auto; }
    .npb-calc__hero { padding: 20px 16px; }
    .npb-calc__reticle { display: none; }
    .npb-calc__form, .npb-results { padding: 14px; }
    .npb-primary__grid, .npb-sections, .npb-box-grid { grid-template-columns: 1fr; }
    .npb-control--wide, .npb-box--full { grid-column: auto; }
    .npb-row { grid-template-columns: 1fr; gap: 5px; }
    .npb-input-line, .npb-input-line--brand { grid-template-columns: 1fr; }
    .npb-actions { flex-direction: column; }
    .npb-results__head { align-items: flex-start; flex-direction: column; }
    .npb-metrics { grid-template-columns: 1fr; }
}

/* v2.1.0: блок патрона сразу после основных параметров и видимый статус расчёта */
.npb-ammo-extra {
    margin: 0;
    padding: 16px;
    background: #f5fbf7;
    border: 0;
    border-top: 4px solid var(--npb-green-soft);
}
.npb-ammo-extra legend {
    padding: 0 8px;
    color: var(--npb-accent-dark);
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: .025em;
}
.npb-ammo-extra__grid {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 5px 20px;
}
.npb-ammo-extra__hint {
    display: block;
    margin-top: 8px;
    color: var(--npb-muted);
}
.npb-calc-status {
    display: inline-flex;
    min-height: 45px;
    align-items: center;
    padding: 8px 12px;
    color: #65777d;
    background: #eef3f4;
    border: 1px solid #d0dde0;
    border-radius: 4px;
}
.npb-calc-status--ok {
    color: #2f6540;
    background: #e8f5e9;
    border-color: #b8d9bd;
}
.npb-missing {
    margin-top: 15px;
    padding: 14px 16px;
    color: #654f29;
    background: #fff8e6;
    border: 1px solid #ead7a5;
    border-radius: 6px;
}
.npb-missing strong {
    display: block;
    margin-bottom: 6px;
    color: #6c5220;
}
.npb-missing ul {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 3px 22px;
    margin: 7px 0 8px 20px;
}
.npb-missing p {
    margin: 0;
    color: #75623c;
    font-size: 13px;
}
.npb-missing--complete {
    color: #2f6540;
    background: #eaf6ec;
    border-color: #b8d9bd;
}
.npb-missing--complete strong,
.npb-missing--complete p {
    display: none;
}
.npb-missing--complete ul {
    display: block;
    margin: 0 0 0 20px;
}
@media (max-width: 680px) {
    .npb-ammo-extra__grid,
    .npb-missing ul {
        grid-template-columns: 1fr;
    }
    .npb-calc-status {
        justify-content: center;
        width: 100%;
    }
}


/* v2.2.0: ярко выделенный блок результата */
.npb-results {
    position: relative;
    margin-top: 0;
    background: #fffdf4;
    border: 4px solid #e7a92f;
    border-top-width: 4px;
    border-radius: 8px;
    box-shadow: 0 14px 34px rgba(110, 78, 19, .18);
}
.npb-result-banner {
    display: flex;
    gap: 14px;
    align-items: center;
    margin: -20px -20px 18px;
    padding: 15px 20px;
    color: #2f3b3f;
    background: #ffd866;
    border-bottom: 1px solid #d9a92a;
}
.npb-result-banner__label {
    flex: 0 0 auto;
    padding: 8px 13px;
    color: #fff;
    font-size: 18px;
    font-weight: 800;
    letter-spacing: .08em;
    background: #b75b16;
    border-radius: 4px;
}
.npb-result-banner strong,
.npb-result-banner span {
    display: block;
}
.npb-result-banner strong {
    font-size: 18px;
}
.npb-result-banner span {
    margin-top: 2px;
    color: #5c4a1f;
    font-size: 13px;
}
.npb-results--active {
    animation: npbResultFlash .75s ease-out;
}
@keyframes npbResultFlash {
    0% { box-shadow: 0 0 0 0 rgba(231, 169, 47, .75), 0 14px 34px rgba(110, 78, 19, .18); }
    100% { box-shadow: 0 0 0 18px rgba(231, 169, 47, 0), 0 14px 34px rgba(110, 78, 19, .18); }
}
.npb-sight-note {
    display: grid;
    grid-template-columns: minmax(170px, .8fr) minmax(220px, 1.2fr);
    gap: 5px 18px;
    align-items: center;
    margin-top: 14px;
    padding: 15px 16px;
    color: #533e18;
    background: #fff1be;
    border: 2px solid #dfaa2d;
    border-radius: 6px;
}
.npb-sight-note > span {
    font-weight: 700;
}
.npb-sight-note > strong {
    color: #a24810;
    font-size: 18px;
}
.npb-sight-note p {
    grid-column: 1 / -1;
    margin: 2px 0 0;
    color: #6b572c;
    font-size: 13px;
}
@media (max-width: 680px) {
    .npb-result-banner {
        margin: -14px -14px 16px;
        align-items: flex-start;
        flex-direction: column;
    }
    .npb-sight-note {
        grid-template-columns: 1fr;
    }
    .npb-sight-note p {
        grid-column: auto;
    }
}

/* v2.3.0: три обязательных поля и однозначный запуск расчёта */
.npb-required-note {
    display: grid;
    gap: 4px;
    margin-bottom: 16px;
    padding: 14px 16px;
    color: #573d16;
    background: #fff2bf;
    border: 2px solid #e4aa24;
    border-radius: 7px;
}
.npb-required-note strong {
    font-size: 16px;
}
.npb-required-note em,
.npb-required-star {
    color: #c52222;
    font-style: normal;
    font-weight: 900;
}
.npb-control--required,
.npb-row--required {
    position: relative;
}
.npb-control--required {
    box-shadow: inset 0 4px 0 rgba(197, 34, 34, .78);
}
.npb-row--required {
    padding: 8px;
    background: #fff8f8;
    border: 1px solid #efc4c4;
    border-radius: 5px;
}
.npb-required-error {
    background: #fff0f0 !important;
    box-shadow: inset 0 0 0 2px #c52222;
}
.npb-required-error input {
    border-color: #c52222 !important;
    box-shadow: 0 0 0 2px rgba(197, 34, 34, .12) !important;
}
.npb-calc-status--error {
    color: #8f1e1e;
    background: #fff0f0;
    border-color: #dda8a8;
}
.npb-results--waiting {
    background: #fafafa;
    border-color: #b9c5c8;
    box-shadow: none;
}
.npb-results--waiting .npb-result-banner {
    background: #e9eef0;
    border-bottom-color: #c2ced1;
}
.npb-results--waiting .npb-result-banner__label {
    background: #71848a;
}
.npb-results--waiting .npb-result-banner span {
    color: #596a70;
}
.npb-results--complete {
    background: #fffdf4;
    border-color: #e7a92f;
    box-shadow: 0 14px 34px rgba(110, 78, 19, .18);
}
.npb-secondary-metrics {
    display: grid;
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 10px;
    margin-top: 12px;
}
.npb-secondary-metrics > div {
    display: flex;
    justify-content: space-between;
    gap: 12px;
    padding: 11px 13px;
    background: #f5f9fa;
    border: 1px solid #d8e4e7;
    border-radius: 5px;
}
.npb-secondary-metrics span {
    color: var(--npb-muted);
    font-size: 12px;
}
.npb-secondary-metrics strong {
    color: #325d68;
    text-align: right;
}
@media (max-width: 680px) {
    .npb-secondary-metrics {
        grid-template-columns: 1fr;
    }
    .npb-row--required {
        padding: 10px;
    }
}


/* v2.4.0: физические показатели и отдельный конвертер уже известной поправки */
.npb-metrics--six {
    grid-template-columns: repeat(3, minmax(0, 1fr));
}
.npb-sight-note {
    margin-top: 15px;
    padding: 15px 16px;
    color: #5d4b25;
    background: #fff4c9;
    border: 2px solid #e7a92f;
    border-radius: 6px;
}
.npb-sight-note span,
.npb-sight-note strong {
    display: block;
}
.npb-sight-note span { font-weight: 700; }
.npb-sight-note strong { margin-top: 3px; color: #b75b17; font-size: 17px; }
.npb-sight-note p { margin: 6px 0 0; }
.npb-converter {
    margin-top: 18px;
    padding: 20px;
    background: #f6fbfc;
    border: 3px solid var(--npb-accent);
    border-radius: 8px;
}
.npb-converter__head {
    display: flex;
    gap: 14px;
    align-items: flex-start;
    margin-bottom: 16px;
}
.npb-converter__badge {
    flex: 0 0 auto;
    padding: 9px 12px;
    color: #fff;
    font-weight: 800;
    letter-spacing: .04em;
    background: var(--npb-accent-dark);
    border-radius: 4px;
}
.npb-converter__head h3 {
    margin: 0;
    color: var(--npb-accent-dark);
    font-family: Georgia, "Times New Roman", serif;
    font-size: 24px;
    font-weight: 400;
}
.npb-converter__head p { margin: 4px 0 0; color: var(--npb-muted); }
.npb-converter__grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 14px;
}
.npb-converter__control {
    display: flex;
    flex-direction: column;
    gap: 7px;
    padding: 14px;
    background: #fff;
    border: 1px solid var(--npb-line);
    border-radius: 6px;
}
.npb-converter__control > span { font-weight: 700; color: #39545d; }
.npb-converter__control input,
.npb-converter__control select {
    width: 100%;
    min-height: 40px;
    padding: 8px 10px;
    color: #2e3f45;
    font: inherit;
    background: #fff;
    border: 1px solid #b9cbd1;
    border-radius: 4px;
}
.npb-converter__control input[aria-invalid="true"] {
    border-color: #c84d3d;
    box-shadow: 0 0 0 2px rgba(200,77,61,.13);
}
.npb-converter__actions {
    grid-column: 1 / -1;
    display: flex;
    gap: 10px;
}
.npb-button--converter {
    flex: 1 1 auto;
    color: #fff;
    background: var(--npb-accent-dark);
    border-color: var(--npb-accent-dark);
}
.npb-converter__results {
    display: grid;
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 12px;
    margin-top: 15px;
}
.npb-converter__results article {
    padding: 15px;
    background: #fff;
    border: 1px solid #cddde1;
    border-radius: 6px;
}
.npb-converter__results span { display: block; color: var(--npb-muted); font-size: 12px; }
.npb-converter__results strong { display: block; margin-top: 7px; color: #315f6a; font-size: 19px; }
.npb-converter__status {
    margin: 12px 0 0;
    padding: 10px 12px;
    color: #596c72;
    background: #eaf2f4;
    border-radius: 4px;
}
.npb-converter--ok .npb-converter__status { color: #2f6540; background: #e8f5e9; }
.npb-converter--error .npb-converter__status { color: #8a352a; background: #fdecea; }
@media (max-width: 900px) {
    .npb-metrics--six { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}
@media (max-width: 680px) {
    .npb-metrics--six,
    .npb-converter__grid,
    .npb-converter__results { grid-template-columns: 1fr; }
    .npb-converter__head { flex-direction: column; }
    .npb-converter__actions { grid-column: auto; flex-direction: column; }
}