.tool-page { background: #f4f7fb; }
.tool-page .site-header { background: rgba(255,255,255,.96); }

.tool-hero { position: relative; overflow: hidden; padding: 82px 0 70px; background: #07172e; color: #fff; }
.tool-hero-grid-bg { position: absolute; inset: 0; opacity: .15; background-image: linear-gradient(rgba(98,167,255,.17) 1px, transparent 1px), linear-gradient(90deg, rgba(98,167,255,.17) 1px, transparent 1px); background-size: 36px 36px; mask-image: linear-gradient(to bottom, #000, transparent 90%); }
.tool-hero::before { content: ""; position: absolute; width: 520px; height: 520px; right: -130px; top: -250px; border-radius: 50%; background: radial-gradient(circle, rgba(40,130,255,.28), transparent 68%); }
.tool-hero-grid { position: relative; display: grid; grid-template-columns: 1.2fr .8fr; gap: 56px; align-items: end; }
.breadcrumb { display: inline-flex; margin-bottom: 26px; color: #9eb2cb; font-size: .92rem; }
.breadcrumb:hover { color: #fff; }
.tool-hero h1 { max-width: 760px; font-size: clamp(2.9rem, 6vw, 5.3rem); line-height: .98; letter-spacing: -.05em; }
.tool-hero h1 sup { color: #4da3ff; font-size: .55em; vertical-align: top; position: relative; top: .1em; }
.tool-hero-lead { max-width: 760px; margin: 25px 0 0; color: #bdc9d8; font-size: 1.13rem; }
.tool-hero-pills { display: flex; gap: 9px; flex-wrap: wrap; margin-top: 28px; }
.tool-hero-pills span { padding: 7px 10px; border: 1px solid rgba(255,255,255,.16); border-radius: 999px; color: #cdd8e6; font-size: .78rem; }
.equation-panel { padding: 26px; border: 1px solid rgba(123,178,242,.24); border-radius: 18px; background: rgba(8,29,56,.76); box-shadow: 0 22px 70px rgba(0,0,0,.22); backdrop-filter: blur(12px); }
.equation-label, .panel-code { display: block; font-size: .72rem; font-weight: 800; letter-spacing: .16em; color: #4da3ff; }
.big-equation { margin: 14px 0 22px; font-size: clamp(1.8rem, 3vw, 2.5rem); font-weight: 800; letter-spacing: -.03em; }
.big-equation > span { display: inline-block; padding: 0 4px 3px; border-bottom: 2px solid #91bdeb; }
.equation-lines { display: grid; gap: 8px; }
.equation-lines div { display: flex; justify-content: space-between; gap: 18px; padding-top: 9px; border-top: 1px solid rgba(255,255,255,.09); color: #b7c8da; }
.equation-lines b { color: #fff; font-weight: 600; }

.calculator-section { padding: 62px 0 82px; }
.calculator-layout { display: grid; grid-template-columns: minmax(0, 1.15fr) minmax(360px, .85fr); gap: 24px; align-items: start; }
.calculator-card, .results-card { border: 1px solid #dce4ee; border-radius: 20px; background: #fff; box-shadow: 0 18px 50px rgba(21,45,77,.07); }
.calculator-card { padding: 28px; }
.results-card { position: sticky; top: 92px; overflow: hidden; }
.calculator-head, .results-head { display: flex; justify-content: space-between; align-items: center; gap: 20px; }
.calculator-head h2 { margin-top: 4px; font-size: 1.8rem; }
.reset-button, .copy-button { appearance: none; border: 1px solid #d1dbe7; background: #fff; color: #3f5168; border-radius: 10px; padding: 9px 12px; cursor: pointer; font-weight: 700; }
.reset-button:hover, .copy-button:hover { border-color: #9eb3c9; color: #07172e; }

.preset-block, .model-block, .target-block { margin-top: 26px; padding-top: 24px; border-top: 1px solid #e4eaf1; }
.field-label { display: block; margin-bottom: 8px; color: #25374e; font-size: .86rem; font-weight: 800; }
.field-label i { font-family: Georgia, serif; font-weight: 400; }
.field-help, .target-note { display: block; margin: 7px 0 0; color: #748298; font-size: .78rem; line-height: 1.45; }
.segmented { display: flex; gap: 6px; padding: 5px; border: 1px solid #d8e1eb; border-radius: 12px; background: #f6f9fc; }
.preset-button, .target-button { appearance: none; border: 0; background: transparent; color: #5b6d83; border-radius: 8px; padding: 9px 12px; cursor: pointer; font-weight: 800; }
.preset-button { flex: 1; }
.preset-button.active, .target-button.active { background: #0b66d8; color: #fff; box-shadow: 0 5px 14px rgba(15,103,216,.18); }

.input-grid { display: grid; grid-template-columns: repeat(2, minmax(0,1fr)); gap: 18px; margin-top: 26px; }
.field { min-width: 0; }
.input-shell, .target-input { display: grid; grid-template-columns: minmax(0,1fr) auto; align-items: center; border: 1px solid #cfd9e5; border-radius: 11px; background: #fff; overflow: hidden; transition: border-color .16s, box-shadow .16s; }
.input-shell:focus-within, .target-input:focus-within, .select-shell:focus-within { border-color: #0f67d8; box-shadow: 0 0 0 3px rgba(15,103,216,.1); }
.input-shell input, .target-input input { width: 100%; min-width: 0; border: 0; outline: 0; padding: 13px 12px; font: inherit; font-size: 1rem; color: #13243b; background: transparent; }
.input-shell em, .target-input span { align-self: stretch; display: flex; align-items: center; padding: 0 11px; border-left: 1px solid #e3e9f0; color: #6e7e91; background: #f7f9fc; font-size: .8rem; font-style: normal; white-space: nowrap; }
.select-shell { display: block; border: 1px solid #cfd9e5; border-radius: 11px; background: #fff; overflow: hidden; }
.select-shell select { width: 100%; border: 0; outline: 0; padding: 13px 42px 13px 12px; font: inherit; color: #1a2c43; background: transparent; }
.manual-cf-field { margin-top: 18px; }

.target-heading { display: flex; justify-content: space-between; gap: 18px; align-items: baseline; }
.target-heading .field-label { margin: 0; }
.target-note { margin: 0; text-align: right; }
.target-row { display: grid; grid-template-columns: 1fr 155px; gap: 12px; align-items: stretch; margin-top: 12px; }
.quick-targets { display: grid; grid-template-columns: repeat(4, 1fr); gap: 6px; padding: 5px; border: 1px solid #d8e1eb; border-radius: 12px; background: #f6f9fc; }
.target-button { padding: 10px; }
.calculate-button { width: 100%; margin-top: 22px; appearance: none; border: 0; border-radius: 12px; padding: 15px 18px; background: #0f67d8; color: #fff; cursor: pointer; font: inherit; font-weight: 800; display: flex; justify-content: center; gap: 10px; align-items: center; }
.calculate-button:hover { background: #0a58bb; }
.form-error { margin-top: 18px; padding: 12px 14px; border: 1px solid #efb4ad; border-radius: 10px; background: #fff2f0; color: #8a2c20; font-size: .9rem; }

.results-head { padding: 22px 24px; border-bottom: 1px solid #e2e8f0; }
.regime-badge { padding: 6px 9px; border-radius: 999px; background: #eaf3ff; color: #0b61c9; font-size: .67rem; font-weight: 900; letter-spacing: .08em; }
.primary-result { padding: 34px 24px 28px; background: linear-gradient(145deg,#07172e,#0c2647); color: #fff; }
.result-label { display: block; color: #9fb1c7; font-size: .78rem; text-transform: uppercase; letter-spacing: .12em; font-weight: 800; }
.primary-result strong { display: inline-block; margin-top: 5px; font-size: clamp(3.1rem, 6vw, 4.7rem); letter-spacing: -.06em; line-height: 1; }
.result-unit { margin-left: 7px; color: #54a5ff; font-size: 1.1rem; font-weight: 800; }
.primary-result p { margin: 9px 0 0; color: #b6c6d8; font-size: .88rem; }
.result-grid { display: grid; grid-template-columns: repeat(2,1fr); }
.result-item { padding: 18px 20px; border-bottom: 1px solid #e6ebf2; }
.result-item:nth-child(odd) { border-right: 1px solid #e6ebf2; }
.result-item span { display: block; color: #718096; font-size: .74rem; }
.result-item strong { display: block; margin-top: 3px; color: #15283f; font-size: 1rem; }
.guidance-box { margin: 20px; padding: 16px; border: 1px solid #cfe0f3; border-radius: 12px; background: #f3f8fe; }
.guidance-box > span { color: #0b61c9; font-size: .68rem; font-weight: 900; letter-spacing: .12em; }
.guidance-box p { margin: 7px 0 0; color: #475c75; font-size: .86rem; }
.copy-button { margin: 0 20px 20px; width: calc(100% - 40px); }

.explain-section { padding: 84px 0; background: #fff; border-top: 1px solid #e0e7ef; }
.explain-grid { display: grid; grid-template-columns: 1.15fr .85fr; gap: 62px; align-items: start; }
.explain-main h2, .assumptions-grid h2, .next-tool-panel h2 { margin-top: 8px; }
.explain-main > p { max-width: 760px; color: #66768a; font-size: 1.03rem; }
.formula-steps { margin-top: 30px; display: grid; grid-template-columns: repeat(2,1fr); border: 1px solid #e0e6ee; border-radius: 16px; overflow: hidden; }
.formula-steps div { display: grid; grid-template-columns: 38px 1fr; gap: 10px; padding: 20px; }
.formula-steps div:nth-child(1), .formula-steps div:nth-child(3) { border-right: 1px solid #e0e6ee; }
.formula-steps div:nth-child(-n+2) { border-bottom: 1px solid #e0e6ee; }
.formula-steps span { color: #0f67d8; font-size: .74rem; font-weight: 900; }
.formula-steps p { margin: 0; color: #5c6c80; }
.formula-steps strong { color: #162940; }
.target-guide { border: 1px solid #dce4ed; border-radius: 18px; padding: 24px; background: #f8fafc; }
.guide-row { display: grid; grid-template-columns: 78px 1fr; gap: 14px; padding: 18px 0; border-top: 1px solid #e0e6ed; }
.guide-row:first-of-type { margin-top: 12px; }
.guide-row > strong { color: #0f67d8; font-size: 1.35rem; }
.guide-row b { color: #182b42; }
.guide-row p { margin: 4px 0 0; color: #708095; font-size: .85rem; }
.guide-row.caution > strong { color: #b16a12; }

.assumptions-section { padding: 80px 0; background: #edf3f8; }
.assumptions-grid { display: grid; grid-template-columns: .75fr 1.25fr; gap: 70px; }
.assumption-list { display: grid; gap: 10px; }
.assumption-list p { margin: 0; padding: 17px 0; border-bottom: 1px solid #d6e0ea; color: #5f7085; }
.assumption-list strong { color: #182b42; }
.next-tool-section { padding: 54px 0 76px; background: #edf3f8; }
.next-tool-panel { display: grid; grid-template-columns: 1fr auto; gap: 40px; align-items: center; padding: 34px; border-radius: 20px; background: #07172e; color: #fff; }
.next-tool-panel p { max-width: 750px; color: #b4c3d4; }
.next-tool-panel .button-ghost { border: 1px solid rgba(255,255,255,.24); color: #fff; white-space: nowrap; }

@media (max-width: 980px) {
  .tool-hero-grid, .calculator-layout, .explain-grid, .assumptions-grid { grid-template-columns: 1fr; }
  .results-card { position: static; }
  .equation-panel { max-width: 620px; }
  .next-tool-panel { grid-template-columns: 1fr; }
}

@media (max-width: 680px) {
  .tool-hero { padding-top: 58px; }
  .calculator-card { padding: 20px; }
  .input-grid, .formula-steps { grid-template-columns: 1fr; }
  .formula-steps div { border-right: 0 !important; border-bottom: 1px solid #e0e6ee; }
  .formula-steps div:last-child { border-bottom: 0; }
  .target-heading { display: block; }
  .target-note { text-align: left; margin-top: 4px; }
  .target-row { grid-template-columns: 1fr; }
  .result-grid { grid-template-columns: 1fr; }
  .result-item:nth-child(odd) { border-right: 0; }
  .guide-row { grid-template-columns: 64px 1fr; }
  .segmented { display: grid; grid-template-columns: 1fr; }
  .tool-hero h1 { font-size: clamp(2.6rem, 14vw, 4rem); }
}