/* ===== ROI Calculator — Kaiten ===== */
/* Design tokens */
:root {
  --radius: 0.625rem;

  --background: oklch(1 0 0);
  --foreground: oklch(0.22 0.02 280);
  --card: oklch(1 0 0);
  --muted-foreground: oklch(0.55 0.02 280);
  --border: oklch(0.92 0.01 280);
  --surface: oklch(0.975 0.005 280);
  --ink-3: oklch(0.62 0.02 280);

  --primary: oklch(0.52 0.19 295);
  --primary-foreground: oklch(1 0 0);
  --primary-soft: oklch(0.96 0.02 295);
  --primary-dark: oklch(0.44 0.20 295);

  --calc-success: #4CAF51;
  --calc-error: #F44336;

  --shadow-card: 0 4px 20px -8px oklch(0 0 0 / 0.08);
}

/* Reset */
*, *::before, *::after { box-sizing: border-box; }
* { margin: 0; padding: 0; border: 0 solid var(--border); }
html, body {
  font-family: 'Roboto', system-ui, -apple-system, sans-serif;
  font-size: 16px;
  font-weight: 400;
  background-color: var(--surface);
  color: var(--foreground);
  -webkit-font-smoothing: antialiased;
  line-height: 1.5;
}
h1, h2, h3, h4 { font-weight: 600; letter-spacing: -0.01em; }
button { font: inherit; cursor: pointer; background: none; }
a { text-decoration: none; color: inherit; }
img { display: block; max-width: 100%; }

/* Layout */
.page {
  min-height: 100vh;
  background: linear-gradient(135deg, oklch(0.97 0.025 295) 0%, oklch(0.97 0.02 280) 50%, oklch(0.97 0.02 200) 100%);
}
.container { max-width: 1080px; margin: 0 auto; padding: 0 16px; }
@media (min-width: 640px) { .container { padding: 0 32px; } }

/* Header */
.header { background: var(--background); border-bottom: 1px solid var(--border); }
.header__inner { height: 64px; display: flex; align-items: center; gap: 32px; }
.header__logo img { height: 36px; width: auto; }
.header__spacer { flex: 1; }
.header__actions { display: flex; align-items: center; gap: 10px; }

/* Buttons */
.btn {
  display: inline-flex; align-items: center; justify-content: center;
  font-size: 13px; font-weight: 500;
  border-radius: var(--radius);
  transition: background-color .15s, color .15s, border-color .15s;
  white-space: nowrap;
}
.btn--primary { background: var(--primary); color: var(--primary-foreground); padding: 10px 20px; }
.btn--primary:hover { background: var(--primary-dark); }
.btn--outline {
  background: var(--background); color: var(--primary);
  border: 1.5px solid var(--primary); padding: 8px 16px;
}
.btn--outline:hover { background: var(--primary-soft); }
.btn--ghost {
  background: var(--background); color: var(--muted-foreground);
  border: 1.5px solid var(--border); padding: 10px 16px; font-size: 14px;
}
.btn--lg { padding: 12px 24px; font-size: 14px; }
.btn--block { width: 100%; }
.btn--flex { flex: 1; }

@media (max-width: 639px) {
  .hide-mobile { display: none !important; }
}

/* Hero */
.hero { padding: 48px 0 16px; }
@media (min-width: 640px) { .hero { padding: 56px 0 24px; } }
.tag {
  display: inline-flex; align-items: center; gap: 6px;
  font-size: 11px; font-weight: 600; text-transform: uppercase; letter-spacing: 0.06em;
  padding: 4px 12px; border-radius: 9999px;
  color: var(--primary); background: var(--primary-soft);
  border: 1px solid oklch(0.78 0.1 295);
  margin-bottom: 20px;
}
.hero__title {
  font-size: 1.8rem; font-weight: 700; line-height: 1.15;
  letter-spacing: -0.01em; max-width: 640px; margin-bottom: 14px;
}
.hero__title em { font-style: normal; color: var(--primary); }
.hero__sub {
  font-size: 16px; color: var(--muted-foreground);
  white-space: nowrap; overflow: hidden; text-overflow: ellipsis;
}
@media (min-width: 640px) { .hero__title { font-size: 2.5rem; } }
@media (min-width: 768px) { .hero__title { font-size: 2.75rem; } }

/* Main */
.main { padding: 32px 0 48px; }

/* Progress */
.progress { display: flex; align-items: center; margin-bottom: 24px; }
.progress__step { display: flex; align-items: center; flex: 1; }
.progress__step:last-child { flex: none; }
.progress__circle {
  width: 28px; height: 28px; border-radius: 9999px;
  font-size: 12px; font-weight: 600;
  display: inline-flex; align-items: center; justify-content: center;
  background: var(--surface); color: var(--ink-3);
  transition: background .2s, color .2s;
}
.progress__label {
  display: none; margin-left: 8px;
  font-size: 16px; color: var(--ink-3);
}
@media (min-width: 640px) { .progress__label { display: inline; } }
.progress__line { flex: 1; height: 1px; margin: 0 8px; background: var(--border); }

.progress__step.is-active .progress__circle { background: var(--primary); color: #fff; }
.progress__step.is-active .progress__label { color: var(--foreground); font-weight: 500; }
.progress__step.is-done .progress__circle { background: var(--calc-success); color: #fff; }
.progress__step.is-done .progress__label { color: var(--calc-success); }

/* Card */
.card {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 20px;
  box-shadow: var(--shadow-card);
}
.card--step { padding: 50px 16px; }
@media (min-width: 640px) { .card--step { padding: 50px 60px; } }
@media (min-width: 1024px) { .card--step { padding: 50px 140px; } }

/* Step blocks */
.q {
  font-size: 1.1rem; font-weight: 600;
  margin-bottom: 20px; padding: 20px 0;
  line-height: 1.3; letter-spacing: -0.01em;
}
@media (min-width: 640px) { .q { font-size: 18px; } }
.field-label {
  margin-bottom: 4px; padding: 20px 0;
  font-size: 18px; font-weight: 700; color: var(--foreground);
}
.big-val {
  font-weight: 700; color: var(--primary);
  font-size: 3rem; line-height: 1; letter-spacing: -0.01em;
  margin-bottom: 8px;
}
.sub { margin: 6px 0 16px; font-size: 14px; color: var(--ink-3); }

/* Range */
.roi-range {
  -webkit-appearance: none; appearance: none;
  width: 100%; height: 4px;
  background: oklch(0.93 0.01 280);
  border-radius: 2px; outline: none; cursor: pointer;
  margin: 14px 0 22px;
}
.roi-range::-webkit-slider-thumb {
  -webkit-appearance: none;
  width: 20px; height: 20px; border-radius: 50%;
  background: var(--primary); border: 3px solid #fff;
  box-shadow: 0 0 0 1.5px var(--primary), 0 2px 6px oklch(0.52 0.19 295 / 0.3);
  cursor: pointer; transition: transform .12s;
}
.roi-range::-webkit-slider-thumb:hover { transform: scale(1.12); }
.roi-range::-moz-range-thumb {
  width: 20px; height: 20px; border-radius: 50%;
  background: var(--primary); border: 3px solid #fff; cursor: pointer;
}

/* Chips */
.chips { display: flex; flex-wrap: wrap; gap: 6px; margin-bottom: 20px; }
.chip {
  padding: 6px 12px; font-size: 16px;
  border-radius: 9999px;
  background: var(--background);
  border: 1.5px solid var(--border);
  color: var(--muted-foreground);
  transition: background .15s, color .15s, border-color .15s;
}
.chip:hover {
  background: var(--primary-soft);
  border-color: oklch(0.78 0.1 295);
  color: var(--primary);
}

/* Step nav */
.step-nav { display: flex; justify-content: center; gap: 10px; margin-top: 16px; }
.step-nav .btn { width: 224px; padding: 12px 0; }

/* Tools grid */
.tools-grid {
  display: grid; grid-template-columns: 1fr; gap: 8px;
  margin-bottom: 12px;
}
@media (min-width: 640px) { .tools-grid { grid-template-columns: 1fr 1fr; } }
.tool {
  display: flex; align-items: center; gap: 8px;
  padding: 10px 12px; border-radius: var(--radius);
  background: #F5F5F5; border: 1.5px solid var(--border);
  text-align: left; transition: background .15s, border-color .15s;
}
.tool__name { flex: 1; font-size: 16px; color: var(--foreground); }
.tool__price { font-size: 16px; white-space: nowrap; color: var(--ink-3); }
.tool.is-active { background: var(--primary-soft); border-color: var(--primary); }
.tool.is-active .tool__name { color: var(--primary); font-weight: 500; }
.tool.is-active .tool__price { color: var(--primary-dark); }

.selected-info {
  padding: 8px 12px; border-radius: var(--radius);
  font-size: 14px; line-height: 1.5; margin-bottom: 8px;
  background: var(--primary-soft);
  border: 1px solid oklch(0.78 0.1 295);
  color: var(--muted-foreground);
}
.selected-info strong { color: var(--foreground); }
.selected-info .accent { color: var(--primary); }

/* Result */
.result__grid {
  display: grid; grid-template-columns: 1fr;
  gap: 8px; margin-bottom: 12px; align-items: stretch;
}
@media (min-width: 768px) {
  .result__grid { grid-template-columns: 1fr auto 1fr; gap: 0; }
}
.result__arrow {
  display: flex; align-items: center; justify-content: center;
  font-size: 18px; color: var(--ink-3);
}
@media (min-width: 768px) { .result__arrow { padding: 0 12px; } }
.result__arrow span { display: inline-block; padding: 4px 0; transform: rotate(90deg); }
@media (min-width: 768px) { .result__arrow span { transform: none; } }

.result__cell {
  text-align: center;
  padding: 32px 24px;
  border-radius: 20px;
  display: flex; flex-direction: column; justify-content: center;
  box-shadow: var(--shadow-card);
}
@media (min-width: 640px) { .result__cell { padding: 36px 24px; } }
.result__cell--loss { background: #FFF5F5; border: 1px solid var(--calc-error); }
.result__cell--gain { background: #F7F4FC; border: 1px solid var(--primary); }
.result__caption {
  font-size: 16px; margin-bottom: 8px;
  display: inline-flex; align-items: center; justify-content: center; gap: 6px;
  color: var(--ink-3);
}
.result__amount {
  font-weight: 700; line-height: 1; letter-spacing: -0.01em;
  font-size: clamp(2.2rem, 8vw, 3.75rem);
  color: var(--calc-error);
}
.result__amount--gain {
  color: var(--primary-dark);
  font-size: clamp(1.75rem, 6vw, 2.75rem);
}
.result__note { font-size: 16px; margin-top: 8px; color: var(--ink-3); line-height: 1.3; }
.result__note strong { color: var(--primary-dark); }

/* Compare */
.compare__col {
  padding: 16px;
  border-radius: 20px;
}
.compare__col--now { background: var(--card); border: 1px solid var(--border); }
.compare__col--kaiten { background: #EAF5EA; border: 1px solid var(--calc-success); }
.compare__title {
  font-size: 11px; font-weight: 600;
  text-transform: uppercase; letter-spacing: 0.06em;
  margin-bottom: 12px; color: var(--ink-3);
}
.compare__col--kaiten .compare__title { color: var(--calc-success); }
.res-row {
  display: flex; align-items: flex-start; gap: 6px;
  margin-bottom: 8px; font-size: 16px; line-height: 1.3;
  color: var(--muted-foreground);
}
.res-row:last-child { margin-bottom: 0; }
.res-row__icon { flex-shrink: 0; margin-top: 2px; width: 18px; height: 18px; }
.res-row__icon--warn { color: var(--calc-error); }
.res-row--green .res-row__icon { color: var(--calc-success); }

/* Tools saved block */
.tools-saved {
  border-radius: 20px;
  padding: 12px 16px;
  margin-bottom: 12px;
  background: var(--surface);
  border: 1px solid var(--border);
}
.tools-saved__label {
  font-size: 11px; font-weight: 600;
  text-transform: uppercase; letter-spacing: 0.06em;
  margin-bottom: 4px; color: var(--ink-3);
}
.tools-saved__row {
  display: flex; justify-content: space-between; align-items: baseline;
  gap: 8px; font-size: 16px; color: var(--muted-foreground);
}
.tools-saved__row span { overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.tools-saved__row strong { color: var(--primary-dark); white-space: nowrap; }

/* CTA */
.cta {
  background: var(--card); border: 1px solid var(--border);
  border-radius: 20px; padding: 24px; margin-bottom: 12px;
  box-shadow: var(--shadow-card);
}
@media (min-width: 640px) { .cta { padding: 28px; } }
.cta__title {
  font-size: 18px; font-weight: 600; margin-bottom: 6px;
  line-height: 1.3; letter-spacing: -0.01em;
}
.cta__sub { font-size: 16px; margin-bottom: 20px; line-height: 1.5; color: var(--ink-3); }
.cta__actions { display: flex; flex-direction: column; gap: 12px; }
@media (min-width: 640px) { .cta__actions { flex-direction: row; } }
.cta__actions .btn { padding: 12px 24px; }

.restart-wrap { text-align: center; margin-top: 16px; }

/* Icons (lucide-style) */
.icon { width: 16px; height: 16px; flex-shrink: 0; }

/* Animations */
@keyframes fade-up {
  from { opacity: 0; transform: translateY(14px); }
  to { opacity: 1; transform: translateY(0); }
}
.fade-up { animation: fade-up .45s cubic-bezier(.16, 1, .3, 1); }

/* Hidden helper */
[hidden] { display: none !important; }

/* ===== Scaling for large screens (2K/4K+) ===== */
/* Auto-generated overrides: values scale with viewport using calc(N * (100vw / 2560)) */
@media (min-width: 2560px) {
  html, body {
    font-size: calc(16 * (100vw / 2560));
  }
  .container {
    max-width: calc(1080 * (100vw / 2560));
    padding: 0 calc(16 * (100vw / 2560));
  }
  .header {
    border-bottom: calc(1 * (100vw / 2560)) solid var(--border);
  }
  .header__inner {
    height: calc(64 * (100vw / 2560));
    gap: calc(32 * (100vw / 2560));
  }
  .header__logo img {
    height: calc(36 * (100vw / 2560));
  }
  .header__actions {
    gap: calc(10 * (100vw / 2560));
  }
  .btn {
    font-size: calc(13 * (100vw / 2560));
  }
  .btn--primary {
    padding: calc(10 * (100vw / 2560)) calc(20 * (100vw / 2560));
  }
  .btn--outline {
    border: calc(1.5 * (100vw / 2560)) solid var(--primary);
    padding: calc(8 * (100vw / 2560)) calc(16 * (100vw / 2560));
  }
  .btn--ghost {
    border: calc(1.5 * (100vw / 2560)) solid var(--border);
    padding: calc(10 * (100vw / 2560)) calc(16 * (100vw / 2560));
    font-size: calc(14 * (100vw / 2560));
  }
  .btn--lg {
    padding: calc(12 * (100vw / 2560)) calc(24 * (100vw / 2560));
    font-size: calc(14 * (100vw / 2560));
  }
  .hero {
    padding: calc(48 * (100vw / 2560)) 0 calc(16 * (100vw / 2560));
  }
  .tag {
    gap: calc(6 * (100vw / 2560));
    font-size: calc(11 * (100vw / 2560));
    padding: calc(4 * (100vw / 2560)) calc(12 * (100vw / 2560));
    border-radius: calc(9999 * (100vw / 2560));
    border: calc(1 * (100vw / 2560)) solid oklch(0.78 0.1 295);
    margin-bottom: calc(20 * (100vw / 2560));
  }
  .hero__title {
    font-size: calc(28.8 * (100vw / 2560));
    max-width: calc(640 * (100vw / 2560));
    margin-bottom: calc(14 * (100vw / 2560));
  }
  .hero__sub {
    font-size: calc(16 * (100vw / 2560));
  }
  .main {
    padding: calc(32 * (100vw / 2560)) 0 calc(48 * (100vw / 2560));
  }
  .progress {
    margin-bottom: calc(24 * (100vw / 2560));
  }
  .progress__circle {
    width: calc(28 * (100vw / 2560));
    height: calc(28 * (100vw / 2560));
    border-radius: calc(9999 * (100vw / 2560));
    font-size: calc(12 * (100vw / 2560));
  }
  .progress__label {
    margin-left: calc(8 * (100vw / 2560));
    font-size: calc(16 * (100vw / 2560));
  }
  .progress__line {
    height: calc(1 * (100vw / 2560));
    margin: 0 calc(8 * (100vw / 2560));
  }
  .card {
    border: calc(1 * (100vw / 2560)) solid var(--border);
    border-radius: calc(20 * (100vw / 2560));
  }
  .card--step {
    padding: calc(50 * (100vw / 2560)) calc(16 * (100vw / 2560));
  }
  .q {
    font-size: calc(17.6 * (100vw / 2560));
    margin-bottom: calc(20 * (100vw / 2560));
    padding: calc(20 * (100vw / 2560)) 0;
  }
  .field-label {
    margin-bottom: calc(4 * (100vw / 2560));
    padding: calc(20 * (100vw / 2560)) 0;
    font-size: calc(18 * (100vw / 2560));
  }
  .big-val {
    font-size: calc(48 * (100vw / 2560));
    margin-bottom: calc(8 * (100vw / 2560));
  }
  .sub {
    margin: calc(6 * (100vw / 2560)) 0 calc(16 * (100vw / 2560));
    font-size: calc(14 * (100vw / 2560));
  }
  .roi-range {
    height: calc(4 * (100vw / 2560));
    border-radius: calc(2 * (100vw / 2560));
    margin: calc(14 * (100vw / 2560)) 0 calc(22 * (100vw / 2560));
  }
  .roi-range::-webkit-slider-thumb {
    width: calc(20 * (100vw / 2560));
    height: calc(20 * (100vw / 2560));
    border: calc(3 * (100vw / 2560)) solid #fff;
    box-shadow: 0 0 0 calc(1.5 * (100vw / 2560)) var(--primary), 0 calc(2 * (100vw / 2560)) calc(6 * (100vw / 2560)) oklch(0.52 0.19 295 / 0.3);
  }
  .roi-range::-moz-range-thumb {
    width: calc(20 * (100vw / 2560));
    height: calc(20 * (100vw / 2560));
    border: calc(3 * (100vw / 2560)) solid #fff;
  }
  .chips {
    gap: calc(6 * (100vw / 2560));
    margin-bottom: calc(20 * (100vw / 2560));
  }
  .chip {
    padding: calc(6 * (100vw / 2560)) calc(12 * (100vw / 2560));
    font-size: calc(16 * (100vw / 2560));
    border-radius: calc(9999 * (100vw / 2560));
    border: calc(1.5 * (100vw / 2560)) solid var(--border);
  }
  .step-nav {
    gap: calc(10 * (100vw / 2560));
    margin-top: calc(16 * (100vw / 2560));
  }
  .step-nav .btn {
    width: calc(224 * (100vw / 2560));
    padding: calc(12 * (100vw / 2560)) 0;
  }
  .tools-grid {
    gap: calc(8 * (100vw / 2560));
    margin-bottom: calc(12 * (100vw / 2560));
  }
  .tool {
    gap: calc(8 * (100vw / 2560));
    padding: calc(10 * (100vw / 2560)) calc(12 * (100vw / 2560));
    border: calc(1.5 * (100vw / 2560)) solid var(--border);
  }
  .tool__name {
    font-size: calc(16 * (100vw / 2560));
  }
  .tool__price {
    font-size: calc(16 * (100vw / 2560));
  }
  .selected-info {
    padding: calc(8 * (100vw / 2560)) calc(12 * (100vw / 2560));
    font-size: calc(14 * (100vw / 2560));
    margin-bottom: calc(8 * (100vw / 2560));
    border: calc(1 * (100vw / 2560)) solid oklch(0.78 0.1 295);
  }
  .result__grid {
    gap: calc(8 * (100vw / 2560));
    margin-bottom: calc(12 * (100vw / 2560));
  }
  .result__arrow {
    font-size: calc(18 * (100vw / 2560));
  }
  .result__arrow span {
    padding: calc(4 * (100vw / 2560)) 0;
  }
  .result__cell {
    padding: calc(32 * (100vw / 2560)) calc(24 * (100vw / 2560));
    border-radius: calc(20 * (100vw / 2560));
  }
  .result__cell--loss {
    border: calc(1 * (100vw / 2560)) solid var(--calc-error);
  }
  .result__cell--gain {
    border: calc(1 * (100vw / 2560)) solid var(--primary);
  }
  .result__caption {
    font-size: calc(16 * (100vw / 2560));
    margin-bottom: calc(8 * (100vw / 2560));
    gap: calc(6 * (100vw / 2560));
  }
  .result__amount {
    font-size: clamp(calc(35.2 * (100vw / 2560)), 8vw, calc(60 * (100vw / 2560)));
  }
  .result__amount--gain {
    font-size: clamp(calc(28 * (100vw / 2560)), 6vw, calc(44 * (100vw / 2560)));
  }
  .result__note {
    font-size: calc(16 * (100vw / 2560));
    margin-top: calc(8 * (100vw / 2560));
  }
  .compare__col {
    padding: calc(16 * (100vw / 2560));
    border-radius: calc(20 * (100vw / 2560));
  }
  .compare__col--now {
    border: calc(1 * (100vw / 2560)) solid var(--border);
  }
  .compare__col--kaiten {
    border: calc(1 * (100vw / 2560)) solid var(--calc-success);
  }
  .compare__title {
    font-size: calc(11 * (100vw / 2560));
    margin-bottom: calc(12 * (100vw / 2560));
  }
  .res-row {
    gap: calc(6 * (100vw / 2560));
    margin-bottom: calc(8 * (100vw / 2560));
    font-size: calc(16 * (100vw / 2560));
  }
  .res-row__icon {
    margin-top: calc(2 * (100vw / 2560));
    width: calc(18 * (100vw / 2560));
    height: calc(18 * (100vw / 2560));
  }
  .tools-saved {
    border-radius: calc(20 * (100vw / 2560));
    padding: calc(12 * (100vw / 2560)) calc(16 * (100vw / 2560));
    margin-bottom: calc(12 * (100vw / 2560));
    border: calc(1 * (100vw / 2560)) solid var(--border);
  }
  .tools-saved__label {
    font-size: calc(11 * (100vw / 2560));
    margin-bottom: calc(4 * (100vw / 2560));
  }
  .tools-saved__row {
    gap: calc(8 * (100vw / 2560));
    font-size: calc(16 * (100vw / 2560));
  }
  .cta {
    border: calc(1 * (100vw / 2560)) solid var(--border);
    border-radius: calc(20 * (100vw / 2560));
    padding: calc(24 * (100vw / 2560));
    margin-bottom: calc(12 * (100vw / 2560));
  }
  .cta__title {
    font-size: calc(18 * (100vw / 2560));
    margin-bottom: calc(6 * (100vw / 2560));
  }
  .cta__sub {
    font-size: calc(16 * (100vw / 2560));
    margin-bottom: calc(20 * (100vw / 2560));
  }
  .cta__actions {
    gap: calc(12 * (100vw / 2560));
  }
  .cta__actions .btn {
    padding: calc(12 * (100vw / 2560)) calc(24 * (100vw / 2560));
  }
  .restart-wrap {
    margin-top: calc(16 * (100vw / 2560));
  }
  .icon {
    width: calc(16 * (100vw / 2560));
    height: calc(16 * (100vw / 2560));
  }
  /* from @media (min-width: 640px) */
  .container {
    padding: 0 calc(32 * (100vw / 2560));
  }
  .hero {
    padding: calc(56 * (100vw / 2560)) 0 calc(24 * (100vw / 2560));
  }
  .hero__title {
    font-size: calc(40 * (100vw / 2560));
  }
  .card--step {
    padding: calc(50 * (100vw / 2560)) calc(60 * (100vw / 2560));
  }
  .q {
    font-size: calc(18 * (100vw / 2560));
  }
  .result__cell {
    padding: calc(36 * (100vw / 2560)) calc(24 * (100vw / 2560));
  }
  .cta {
    padding: calc(28 * (100vw / 2560));
  }
  /* from @media (min-width: 768px) */
  .hero__title {
    font-size: calc(44 * (100vw / 2560));
  }
  .result__arrow {
    padding: 0 calc(12 * (100vw / 2560));
  }
  /* from @media (min-width: 1024px) */
  .card--step {
    padding: calc(50 * (100vw / 2560)) calc(140 * (100vw / 2560));
  }
}