.fvc-calculator,
.fvc-calculator * {
    box-sizing: border-box;
}

.fvc-calculator {
    --fvc-bg: #050714;
    --fvc-panel: rgba(12, 18, 38, .86);
    --fvc-cyan: #20f7ff;
    --fvc-green: #72ff79;
    --fvc-pink: #ff3bd4;
    --fvc-yellow: #ffe86a;
    --fvc-text: #f6fbff;
    --fvc-muted: #aebbd0;
    position: relative;
    isolation: isolate;
    width: min(100%, 920px);
    margin: 28px auto;
    padding: clamp(20px, 4vw, 38px);
    overflow: hidden;
    color: var(--fvc-text);
    font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
    background:
        linear-gradient(135deg, rgba(32,247,255,.09), transparent 36%),
        linear-gradient(315deg, rgba(255,59,212,.09), transparent 42%),
        var(--fvc-bg);
    border: 1px solid rgba(32,247,255,.42);
    border-radius: 26px;
    box-shadow: 0 0 28px rgba(32,247,255,.16), 0 24px 70px rgba(0,0,0,.4);
}

.fvc-calculator::before {
    content: "";
    position: absolute;
    inset: 0;
    z-index: -2;
    background-image:
        linear-gradient(rgba(255,255,255,.025) 1px, transparent 1px),
        linear-gradient(90deg, rgba(255,255,255,.025) 1px, transparent 1px);
    background-size: 28px 28px;
    mask-image: linear-gradient(to bottom, #000, transparent 92%);
}

.fvc-glow {
    position: absolute;
    z-index: -1;
    width: 250px;
    height: 250px;
    border-radius: 50%;
    filter: blur(85px);
    opacity: .2;
    pointer-events: none;
}
.fvc-glow-one { top: -100px; left: -80px; background: var(--fvc-cyan); }
.fvc-glow-two { right: -90px; bottom: -100px; background: var(--fvc-pink); }

.fvc-header {
    display: grid;
    grid-template-columns: auto 1fr auto;
    gap: 16px;
    align-items: start;
    margin-bottom: 22px;
}

.fvc-icon {
    display: grid;
    place-items: center;
    width: 58px;
    height: 58px;
    font-size: 30px;
    border: 1px solid rgba(114,255,121,.55);
    border-radius: 18px;
    background: rgba(114,255,121,.09);
    box-shadow: inset 0 0 18px rgba(114,255,121,.09), 0 0 20px rgba(114,255,121,.12);
}

.fvc-kicker {
    margin: 0 0 4px;
    color: var(--fvc-green);
    font-size: 12px;
    font-weight: 800;
    letter-spacing: .16em;
    text-transform: uppercase;
}

.fvc-header h2 {
    margin: 0;
    color: #fff;
    font-size: clamp(26px, 5vw, 42px);
    line-height: 1.06;
    text-shadow: 0 0 16px rgba(32,247,255,.35);
}

.fvc-header p:last-child {
    max-width: 660px;
    margin: 9px 0 0;
    color: var(--fvc-muted);
    line-height: 1.65;
}

.fvc-sound {
    display: grid;
    place-items: center;
    width: 44px;
    height: 44px;
    padding: 0;
    color: #fff;
    font-size: 19px;
    cursor: pointer;
    border: 1px solid rgba(255,255,255,.16);
    border-radius: 14px;
    background: rgba(255,255,255,.07);
    transition: .2s ease;
}
.fvc-sound:hover { transform: translateY(-2px); border-color: var(--fvc-cyan); box-shadow: 0 0 16px rgba(32,247,255,.18); }

.fvc-formula {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    justify-content: center;
    gap: 10px;
    margin: 0 0 24px;
    padding: 18px;
    color: var(--fvc-cyan);
    font-size: clamp(25px, 5vw, 39px);
    font-weight: 900;
    border: 1px solid rgba(32,247,255,.25);
    border-radius: 20px;
    background: linear-gradient(90deg, rgba(32,247,255,.06), rgba(255,59,212,.055));
    box-shadow: inset 0 0 24px rgba(32,247,255,.045);
}
.fvc-formula b { color: var(--fvc-pink); }
.fvc-formula small {
    flex-basis: 100%;
    color: var(--fvc-muted);
    font-size: 13px;
    font-weight: 600;
    text-align: center;
    letter-spacing: .03em;
}

.fvc-grid {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 18px;
}

.fvc-input-card {
    padding: 18px;
    border: 1px solid rgba(255,255,255,.11);
    border-radius: 18px;
    background: var(--fvc-panel);
    box-shadow: inset 0 1px rgba(255,255,255,.04);
}

.fvc-input-card label {
    display: block;
    margin-bottom: 10px;
    color: #fff;
    font-size: 14px;
    font-weight: 800;
}

.fvc-input-row {
    display: grid;
    grid-template-columns: minmax(0, 1fr) minmax(138px, .72fr);
    gap: 10px;
}

.fvc-input-row input,
.fvc-input-row select {
    width: 100%;
    min-height: 50px;
    color: #fff;
    font: inherit;
    border: 1px solid rgba(32,247,255,.22);
    border-radius: 13px;
    outline: none;
    background: #080d1f;
    transition: border-color .2s ease, box-shadow .2s ease, transform .2s ease;
}
.fvc-input-row input { padding: 0 15px; font-size: 17px; font-weight: 750; }
.fvc-input-row select { padding: 0 12px; color-scheme: dark; cursor: pointer; }
.fvc-input-row input::placeholder { color: #71809b; }
.fvc-input-row input:focus,
.fvc-input-row select:focus {
    border-color: var(--fvc-cyan);
    box-shadow: 0 0 0 3px rgba(32,247,255,.11), 0 0 18px rgba(32,247,255,.12);
}

.fvc-actions {
    display: flex;
    gap: 12px;
    margin-top: 20px;
}

.fvc-btn {
    min-height: 52px;
    padding: 0 22px;
    color: #061018;
    font: inherit;
    font-weight: 900;
    cursor: pointer;
    border: 0;
    border-radius: 15px;
    transition: transform .18s ease, box-shadow .18s ease, filter .18s ease;
}
.fvc-btn:hover { transform: translateY(-2px); filter: brightness(1.06); }
.fvc-btn:active { transform: translateY(0) scale(.985); }
.fvc-calculate {
    flex: 1;
    background: linear-gradient(90deg, var(--fvc-cyan), var(--fvc-green));
    box-shadow: 0 0 22px rgba(32,247,255,.22);
}
.fvc-reset {
    color: #fff;
    background: linear-gradient(90deg, #8c2cff, var(--fvc-pink));
    box-shadow: 0 0 20px rgba(255,59,212,.18);
}

.fvc-alert {
    margin-top: 16px;
    padding: 13px 15px;
    color: #ffd4df;
    font-weight: 700;
    border: 1px solid rgba(255,82,128,.5);
    border-radius: 13px;
    background: rgba(255,45,100,.1);
}

.fvc-results {
    margin-top: 22px;
    animation: fvc-rise .36s ease both;
}
@keyframes fvc-rise { from { opacity: 0; transform: translateY(9px); } to { opacity: 1; transform: translateY(0); } }

.fvc-result-main {
    position: relative;
    padding: 25px 86px 25px 25px;
    overflow: hidden;
    border: 1px solid rgba(114,255,121,.36);
    border-radius: 20px;
    background: linear-gradient(135deg, rgba(114,255,121,.11), rgba(32,247,255,.075));
    box-shadow: inset 0 0 28px rgba(114,255,121,.045), 0 0 24px rgba(114,255,121,.08);
}
.fvc-result-main p { margin: 0 0 8px; color: var(--fvc-muted); font-weight: 750; }
.fvc-main-value { display: flex; flex-wrap: wrap; align-items: baseline; gap: 10px; }
.fvc-main-value strong {
    color: var(--fvc-green);
    font-size: clamp(36px, 8vw, 61px);
    line-height: 1;
    text-shadow: 0 0 16px rgba(114,255,121,.28);
    overflow-wrap: anywhere;
}
.fvc-main-value span { color: #fff; font-size: 21px; font-weight: 900; }
.fvc-copy {
    position: absolute;
    top: 20px;
    right: 20px;
    min-height: 38px;
    padding: 0 12px;
    color: #fff;
    font: inherit;
    font-size: 13px;
    font-weight: 800;
    cursor: pointer;
    border: 1px solid rgba(255,255,255,.16);
    border-radius: 11px;
    background: rgba(255,255,255,.075);
}

.fvc-conversions {
    display: grid;
    grid-template-columns: repeat(4, minmax(0, 1fr));
    gap: 12px;
    margin-top: 14px;
}
.fvc-conversions article {
    min-width: 0;
    padding: 16px;
    border: 1px solid rgba(255,255,255,.1);
    border-radius: 16px;
    background: rgba(10,15,31,.78);
}
.fvc-conversions span { display: block; color: var(--fvc-pink); font-size: 12px; font-weight: 900; text-transform: uppercase; letter-spacing: .1em; }
.fvc-conversions strong { display: block; margin: 6px 0; color: var(--fvc-yellow); font-size: 22px; overflow-wrap: anywhere; }
.fvc-conversions small { color: var(--fvc-muted); line-height: 1.35; }

.fvc-steps {
    margin-top: 14px;
    padding: 20px;
    border-left: 4px solid var(--fvc-cyan);
    border-radius: 4px 16px 16px 4px;
    background: rgba(32,247,255,.055);
}
.fvc-steps h3 { margin: 0 0 11px; color: #fff; font-size: 16px; }
.fvc-steps p { margin: 7px 0; color: #cbd6e8; line-height: 1.55; overflow-wrap: anywhere; }
.fvc-step-answer { color: var(--fvc-green) !important; font-weight: 850; }

.fvc-footer {
    margin-top: 18px;
    padding-top: 16px;
    color: #8491aa;
    font-size: 12px;
    line-height: 1.55;
    border-top: 1px solid rgba(255,255,255,.08);
}

@media (max-width: 720px) {
    .fvc-header { grid-template-columns: auto 1fr; }
    .fvc-sound { grid-column: 2; grid-row: 1; justify-self: end; }
    .fvc-grid { grid-template-columns: 1fr; }
    .fvc-conversions { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}

@media (max-width: 520px) {
    .fvc-calculator { padding: 18px; border-radius: 20px; }
    .fvc-header { gap: 12px; }
    .fvc-icon { width: 48px; height: 48px; font-size: 24px; border-radius: 15px; }
    .fvc-input-row { grid-template-columns: 1fr; }
    .fvc-actions { flex-direction: column; }
    .fvc-btn { width: 100%; }
    .fvc-result-main { padding: 22px 18px; }
    .fvc-copy { position: static; margin-top: 16px; }
    .fvc-conversions { grid-template-columns: 1fr; }
}