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

.bk-calculator {
    --bk-primary: #667ee5;
    --bk-primary-dark: #435cc2;
    --bk-primary-soft: #eef1ff;
    --bk-text: #666b74;
    --bk-heading: #657ee4;
    --bk-line: #d8dbe2;
    --bk-surface: rgba(255, 255, 255, .96);
    --bk-muted: #eeeeef;
    --bk-success: #55b800;
    --bk-danger: #ea3737;
    position: relative;
    width: 100%;
    min-height: 760px;
    overflow: hidden;
    isolation: isolate;
    font-family: Arial, Helvetica, sans-serif;
    color: var(--bk-text);
    background:
        linear-gradient(180deg, rgba(222, 238, 250, .76), rgba(239, 246, 255, .88)),
        radial-gradient(circle at 12% 22%, rgba(92, 207, 188, .45), transparent 27%),
        radial-gradient(circle at 82% 26%, rgba(105, 142, 204, .42), transparent 32%),
        linear-gradient(112deg, #d4e9f3 0%, #f8fbff 48%, #b9d2e4 100%);
}

.bk-calculator::before,
.bk-calculator::after {
    content: "";
    position: absolute;
    inset: 78px -4% -12%;
    z-index: -1;
    pointer-events: none;
}

.bk-calculator::before {
    opacity: .7;
    filter: blur(20px);
    background:
        linear-gradient(90deg, transparent 0 7%, rgba(255,255,255,.76) 7% 13%, transparent 13% 20%, rgba(75,132,161,.34) 20% 27%, transparent 27% 46%, rgba(255,255,255,.75) 46% 62%, transparent 62% 72%, rgba(51,94,126,.34) 72% 79%, transparent 79%),
        linear-gradient(180deg, transparent 0 17%, rgba(255,255,255,.72) 17% 27%, transparent 27% 50%, rgba(35,85,113,.28) 50% 57%, transparent 57% 72%, rgba(255,255,255,.8) 72% 82%, transparent 82%);
    transform: scale(1.08);
}

.bk-calculator::after {
    background: linear-gradient(180deg, transparent 65%, rgba(236,244,255,.88));
}

.bk-calculator__titlebar {
    display: flex;
    min-height: 82px;
    align-items: center;
    justify-content: center;
    padding: 18px 24px;
    color: #fff;
    font-size: clamp(16px, 2vw, 22px);
    font-weight: 700;
    letter-spacing: .035em;
    text-align: center;
    text-transform: uppercase;
    background: linear-gradient(90deg, #5374df, #315abb 45%, #5572d7);
    box-shadow: inset 0 -3px rgba(31, 81, 175, .55);
}

.bk-calculator__stage {
    display: flex;
    justify-content: center;
    padding: clamp(70px, 8vw, 110px) 24px 90px;
}

.bk-calculator__panel {
    width: min(1080px, 100%);
    overflow: hidden;
    background: var(--bk-surface);
    border: 1px solid rgba(255,255,255,.9);
    border-radius: 0 0 16px 16px;
    box-shadow: 0 5px 18px rgba(37, 58, 83, .28), 0 22px 70px rgba(65, 111, 145, .18);
    backdrop-filter: blur(8px);
}

.bk-progress {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    min-height: 104px;
    background: #e9e9ea;
}

.bk-progress__step {
    position: relative;
    z-index: 1;
    min-width: 0;
    margin: 0 -17px 0 0;
    padding: 18px 28px 18px 40px;
    border: 0;
    color: #969696;
    font: inherit;
    font-size: clamp(13px, 1.5vw, 17px);
    font-weight: 700;
    text-align: left;
    cursor: default;
    background: #e9e9ea;
    clip-path: polygon(0 0, calc(100% - 18px) 0, 100% 50%, calc(100% - 18px) 100%, 0 100%, 18px 50%);
}

.bk-progress__step:first-child { padding-left: 28px; clip-path: polygon(0 0, calc(100% - 18px) 0, 100% 50%, calc(100% - 18px) 100%, 0 100%); }
.bk-progress__step:last-child { margin-right: 0; clip-path: polygon(0 0, 100% 0, 100% 100%, 0 100%, 18px 50%); }
.bk-progress__step:not(:last-child)::after { content: ""; position: absolute; top: 0; right: 17px; width: 2px; height: 100%; background: rgba(255,255,255,.8); transform: skewX(-19deg); }
.bk-progress__step.is-active { z-index: 3; color: #fff; background: var(--bk-primary); }
.bk-progress__step.is-complete { color: #747474; }
.bk-progress__step span { margin-right: 4px; }

.bk-form { padding: 36px clamp(34px, 6vw, 90px) 42px; }
.bk-step[hidden] { display: none !important; }
.bk-step { animation: bk-fade .22s ease; }
@keyframes bk-fade { from { opacity: 0; transform: translateY(6px); } to { opacity: 1; transform: none; } }

.bk-step > h2,
.bk-section-title,
.bk-summary-title {
    margin: 0 0 30px;
    color: var(--bk-heading);
    font-size: clamp(20px, 2.4vw, 25px);
    line-height: 1.2;
    text-align: center;
}
.bk-section-title { margin-top: 48px; }
.bk-step-intro { max-width: 720px; margin: -12px auto 30px; text-align: center; line-height: 1.6; }

.bk-grid { display: grid; gap: 24px; }
.bk-grid--2 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
.bk-grid--3 { grid-template-columns: repeat(3, minmax(0, 1fr)); }
.bk-grid--email { align-items: end; }

.bk-field { position: relative; margin-bottom: 24px; }
.bk-field label { display: block; margin: 0 0 9px; color: #6d6f75; font-size: 14px; font-weight: 700; }
.bk-field label span { color: var(--bk-danger); }
.bk-field input,
.bk-field select,
.bk-field textarea {
    width: 100%;
    min-height: 44px;
    padding: 10px 15px;
    border: 2px solid var(--bk-line);
    border-radius: 8px;
    outline: none;
    color: #333;
    background: rgba(255,255,255,.85);
    font: inherit;
    font-size: 16px;
    transition: border-color .18s ease, box-shadow .18s ease, background .18s ease;
}
.bk-field textarea { min-height: 100px; resize: vertical; }
.bk-field input:focus,
.bk-field select:focus,
.bk-field textarea:focus,
.bk-field.is-focused input { border-color: var(--bk-primary); box-shadow: 0 0 0 3px rgba(102,126,229,.12); background: #fff; }
.bk-field.is-valid input { border-color: var(--bk-success); }
.bk-field.is-invalid input,
.bk-field.is-invalid select,
.bk-field.is-invalid textarea { border-color: var(--bk-danger); }
.bk-validation-icon { position: absolute; right: 14px; bottom: 12px; color: var(--bk-success); font-weight: 800; }
.bk-field-error { min-height: 18px; margin: 5px 0 0; color: var(--bk-danger); font-size: 13px; }

.bk-field--range { margin-bottom: 30px; }
.bk-field--range label { margin-bottom: 20px; }
.bk-field--range input[type="range"] {
    --bk-range-progress: 0%;
    display: block;
    min-height: auto;
    height: 8px;
    padding: 0;
    border: 0;
    border-radius: 99px;
    appearance: none;
    background: linear-gradient(90deg, var(--bk-primary) 0 var(--bk-range-progress), #d7d7d8 var(--bk-range-progress) 100%);
}
.bk-field--range input[type="range"]::-webkit-slider-thumb { width: 28px; height: 28px; border: 0; border-radius: 50%; appearance: none; cursor: pointer; background: var(--bk-primary); box-shadow: 0 3px 10px rgba(67,92,194,.3); }
.bk-field--range input[type="range"]::-moz-range-thumb { width: 28px; height: 28px; border: 0; border-radius: 50%; cursor: pointer; background: var(--bk-primary); box-shadow: 0 3px 10px rgba(67,92,194,.3); }
.bk-range-output { position: absolute; top: 36px; left: clamp(20px, var(--bk-output-left, 0%), calc(100% - 20px)); transform: translateX(-50%); min-width: 45px; padding: 4px 7px; border-radius: 20px; color: #fff; background: var(--bk-primary-dark); font-size: 11px; font-weight: 700; text-align: center; pointer-events: none; }
.bk-range-ticks { display: grid; grid-template-columns: repeat(10, 1fr); gap: 0; margin-top: 22px; color: #73767b; font-size: 12px; font-weight: 700; text-align: center; }
.bk-range-ticks span:first-child { text-align: left; }
.bk-range-ticks span:last-child { text-align: right; }

.bk-check { display: flex; align-items: flex-start; gap: 10px; color: #6d6f75; font-size: 14px; font-weight: 700; line-height: 1.45; cursor: pointer; }
.bk-check input { width: 19px; height: 19px; flex: 0 0 auto; margin: 0; accent-color: var(--bk-primary); }
.bk-check a { color: var(--bk-primary); font-weight: 700; text-decoration: none; }
.bk-check a:hover { text-decoration: underline; }
.bk-check--standalone { margin: 6px 0 28px; }
.bk-check--consent { padding-bottom: 28px; }
.bk-check--final { margin: 18px 0 0; }

.bk-years { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 22px; margin-bottom: 6px; }

.bk-package-grid { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 28px; }
.bk-package {
    display: flex;
    min-width: 0;
    flex-direction: column;
    align-items: center;
    padding: 24px 16px 18px;
    border: 2px solid transparent;
    border-radius: 9px;
    outline: none;
    background: #fff;
    box-shadow: 0 2px 10px rgba(37, 44, 61, .28);
    text-align: center;
    transition: transform .16s ease, border-color .16s ease, box-shadow .16s ease;
}
.bk-package:hover,
.bk-package:focus-visible { transform: translateY(-2px); border-color: rgba(102,126,229,.5); box-shadow: 0 8px 22px rgba(49,69,133,.22); }
.bk-package.is-selected { border-color: var(--bk-primary-dark); box-shadow: 0 8px 24px rgba(67,92,194,.25); }
.bk-package.is-disabled { opacity: .58; pointer-events: none; }
.bk-package__brand { min-height: 43px; display: flex; align-items: center; color: #2a6a60; font-size: 20px; font-weight: 800; font-style: italic; }
.bk-package__rating { margin: 6px 0 4px; color: var(--bk-primary); font-size: 19px; letter-spacing: 2px; }
.bk-package__name { color: var(--bk-primary); font-size: 14px; }
.bk-package__divider { width: 100%; height: 1px; margin: 12px 0; background: #d9d9d9; }
.bk-package__meta { color: #777; font-size: 11px; text-transform: uppercase; }
.bk-package__price { margin-top: 4px; color: var(--bk-primary); font-size: 20px; }
.bk-package__per-person { min-height: 17px; margin-top: 2px; color: #8a8d93; font-size: 11px; }
.bk-package__duration { color: var(--bk-primary); font-size: 18px; }
.bk-package__info { color: var(--bk-primary); font-size: 13px; font-weight: 700; text-decoration: none; }
.bk-package__choose { width: 82%; min-height: 40px; margin-top: 22px; border: 0; border-radius: 3px; color: #fff; background: var(--bk-primary); font-weight: 800; text-transform: uppercase; cursor: pointer; box-shadow: 0 3px 0 var(--bk-primary-dark); }
.bk-package__choose:hover { background: var(--bk-primary-dark); }
.bk-package small { margin-top: 14px; color: #999; font-size: 9px; text-transform: uppercase; }

.bk-validation-demo { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 28px; margin-top: 24px; }
.bk-validation-demo .bk-field { margin-bottom: 0; }

.bk-summary-title { margin-top: 34px; text-transform: uppercase; }
.bk-summary { margin: 0 -90px; }
.bk-summary__row { display: grid; grid-template-columns: minmax(240px, 1fr) minmax(220px, 1fr); gap: 24px; min-height: 42px; align-items: center; padding: 8px 90px; }
.bk-summary__row:nth-child(odd) { background: rgba(232,235,241,.66); }
.bk-summary dt { font-weight: 700; }
.bk-summary dd { margin: 0; color: var(--bk-primary); font-weight: 700; text-align: right; }

.bk-actions { display: flex; justify-content: space-between; gap: 18px; margin-top: 40px; }
.bk-button { min-width: min(340px, 46%); min-height: 48px; padding: 12px 28px; border: 0; border-radius: 7px; color: #fff; font: inherit; font-size: 15px; font-weight: 800; letter-spacing: .04em; text-transform: uppercase; cursor: pointer; transition: transform .14s ease, filter .14s ease; }
.bk-button:hover { transform: translateY(-1px); filter: brightness(.96); }
.bk-button:disabled { opacity: .6; cursor: wait; transform: none; }
.bk-button--primary { margin-left: auto; background: var(--bk-primary); box-shadow: 0 3px 0 var(--bk-primary-dark); }
.bk-button--secondary { color: #fff; background: #bdbdbd; box-shadow: 0 3px 0 #a5a5a5; }

.bk-alert { margin: 0 0 24px; padding: 13px 16px; border: 1px solid #ffd2d2; border-radius: 8px; color: #8b2020; background: #fff5f5; }
.bk-alert.is-success { border-color: #b8dfc1; color: #176b2f; background: #f2fff5; }
.bk-honeypot { position: absolute !important; left: -10000px !important; width: 1px !important; height: 1px !important; overflow: hidden !important; }

@media (max-width: 980px) {
    .bk-package-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
    .bk-years { grid-template-columns: repeat(2, minmax(0, 1fr)); }
    .bk-progress { min-height: 84px; }
    .bk-progress__step { padding-left: 30px; font-size: 13px; }
    .bk-summary { margin-inline: -45px; }
    .bk-summary__row { padding-inline: 45px; }
}

@media (max-width: 680px) {
    .bk-calculator { min-height: 0; }
    .bk-calculator__titlebar { min-height: 68px; font-size: 15px; }
    .bk-calculator__stage { padding: 34px 12px 54px; }
    .bk-calculator__panel { border-radius: 0 0 12px 12px; }
    .bk-progress { grid-template-columns: 1fr; min-height: 68px; }
    .bk-progress__step { display: none; min-height: 68px; margin: 0; padding: 16px 22px; clip-path: none !important; text-align: center; }
    .bk-progress__step.is-active { display: block; }
    .bk-progress__step::after { display: none; }
    .bk-form { padding: 28px 20px 30px; }
    .bk-grid--2,
    .bk-grid--3,
    .bk-years,
    .bk-validation-demo { grid-template-columns: 1fr; gap: 0; }
    .bk-package-grid { grid-template-columns: 1fr; gap: 20px; }
    .bk-package { max-width: 380px; width: 100%; margin-inline: auto; }
    .bk-range-ticks { font-size: 0; }
    .bk-range-ticks span:nth-child(1),
    .bk-range-ticks span:nth-child(5),
    .bk-range-ticks span:nth-child(10) { font-size: 11px; }
    .bk-summary { margin-inline: -20px; }
    .bk-summary__row { grid-template-columns: 1fr; gap: 3px; padding: 10px 20px; }
    .bk-summary dd { text-align: left; }
    .bk-actions { flex-direction: column-reverse; }
    .bk-button { width: 100%; min-width: 0; }
}