:root {
  --ink: #1c232e;
  --muted: #596370;
  --line: #cfd6dc;
  --paper: #f7f8f8;
  --cyan: #007e87;
  --coral: #c7563d;
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  color: var(--ink);
  background: var(--paper);
  font-family: Arial, Helvetica, sans-serif;
  line-height: 1.5;
}

.page-shell { width: min(1440px, calc(100% - 48px)); margin: 0 auto; }

.site-header {
  border-bottom: 1px solid var(--line);
  background: #fff;
}

.header-inner { min-height: 66px; display: flex; align-items: center; justify-content: space-between; gap: 24px; }

.wordmark { color: var(--ink); font-weight: 700; font-size: 1.25rem; letter-spacing: .08em; text-decoration: none; }
.header-inner p { margin: 0; color: var(--muted); font-size: .9rem; }

.intro { padding: 70px 0 44px; max-width: 980px; margin-left: max(24px, calc((100% - 1440px) / 2)); }
.eyebrow, .case-kicker { margin: 0; color: var(--cyan); font-size: .76rem; font-weight: 700; letter-spacing: .12em; text-transform: uppercase; }
h1, h2 { margin: 0; letter-spacing: 0; }
h1 { margin-top: 8px; font-family: Georgia, 'Times New Roman', serif; font-size: clamp(2.3rem, 5vw, 4.8rem); line-height: 1.05; font-weight: 500; }
.lede { max-width: 780px; margin: 22px 0 0; color: var(--muted); font-size: 1.08rem; }

.browser { padding-bottom: 64px; }
.case-switcher { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 10px; margin-bottom: 22px; }
.case-button { min-height: 60px; border: 1px solid var(--line); background: #fff; color: var(--ink); cursor: pointer; font: inherit; font-size: .95rem; font-weight: 700; text-align: left; padding: 11px 14px; transition: background .16s ease, border-color .16s ease, color .16s ease; }
.case-button span { display: block; margin-top: 3px; color: var(--muted); font-size: .79rem; font-weight: 400; }
.case-button:hover, .case-button:focus-visible { border-color: var(--cyan); outline: none; }
.case-button.active { border-color: var(--cyan); background: var(--cyan); color: #fff; }
.case-button.active span { color: #dff4f2; }
.case-study { border-top: 2px solid var(--ink); padding: 24px 0 48px; }
.case-header { display: flex; align-items: start; justify-content: space-between; gap: 36px; margin-bottom: 26px; }
h2 { margin-top: 3px; font-size: clamp(1.45rem, 2vw, 2rem); font-weight: 600; }

.physics4 { display: grid; grid-template-columns: repeat(5, minmax(100px, 1fr)); gap: 14px 20px; margin: 0; min-width: min(770px, 100%); }
.physics4 div { border-left: 2px solid var(--coral); padding-left: 9px; }
.physics4 dt { color: var(--muted); font-size: .73rem; line-height: 1.2; }
.physics4 dd { margin: 3px 0 0; font-size: .94rem; font-weight: 700; white-space: nowrap; }

.case-grid { display: grid; grid-template-columns: .82fr 1.36fr 1fr; gap: 20px; align-items: start; }
figure { margin: 0; min-width: 0; }
figure img { display: block; width: 100%; height: auto; border: 1px solid var(--line); background: #fff; }
figcaption { margin-top: 8px; color: var(--muted); font-size: .87rem; }
.field-toolbar { display: flex; align-items: center; justify-content: space-between; gap: 12px; min-height: 37px; margin-bottom: 8px; }
.field-toolbar label { color: var(--muted); font-size: .83rem; }
.field-toolbar select { max-width: 155px; min-height: 32px; border: 1px solid var(--line); background: #fff; color: var(--ink); font: inherit; font-size: .83rem; padding: 4px 8px; }

footer { border-top: 1px solid var(--line); background: #fff; color: var(--muted); font-size: .82rem; }
footer p { margin: 0; padding: 24px 0; }

@media (max-width: 1050px) {
  .case-header { display: block; }
  .physics4 { margin-top: 20px; min-width: 0; }
  .case-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .case-grid figure:first-child { max-width: 460px; }
}

@media (max-width: 680px) {
  .page-shell { width: min(100% - 28px, 1440px); }
  .header-inner { min-height: 58px; }
  .header-inner p { display: none; }
  .intro { padding: 44px 0 32px; margin-left: 14px; }
  .physics4 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .case-switcher { grid-template-columns: 1fr; }
  .case-grid { grid-template-columns: 1fr; }
  .case-grid figure:first-child { max-width: none; }
}