/* Industry — design-system tokens and component classes. */

:root {
  --color-bg: #f2f2f3;
  --color-surface: #e9e9ea;
  --color-text: #1d1f20;
  --color-accent: #5980a6;
  --color-divider: color-mix(in srgb, #1d1f20 16%, transparent);

  /* Tonal ramp — generated in OKLCH. */
  --color-accent-100: #eef6ff;
  --color-accent-200: #d6ebff;
  --color-accent-300: #b5d9fd;
  --color-accent-400: #94bce3;
  --color-accent-500: #749dc4;
  --color-accent-600: #597ea3;
  --color-accent-700: #416180;
  --color-accent-800: #2c455d;
  --color-accent-900: #1d2d3d;

  --font-heading: "Barlow Condensed", system-ui, sans-serif;
  --font-heading-weight: 600;
  --font-body: "Barlow", system-ui, sans-serif;

  --space-1: 3.4px;
  --space-2: 6.8px;
  --space-3: 10.2px;
  --space-4: 13.6px;
  --space-6: 20.4px;
  --space-8: 27.2px;
}

body {
  background: var(--color-bg);
  color: var(--color-text);
  font-family: var(--font-body);
}

.blueprint {
  position: relative;
  border: 1px solid var(--color-divider);
}
.blueprint > .corner {
  position: absolute; width: 11px; height: 11px;
  color: color-mix(in srgb, var(--color-text) 55%, transparent);
}
.blueprint > .corner::before, .blueprint > .corner::after {
  content: ""; position: absolute; background: currentColor;
}
.blueprint > .corner::before { left: 5px; top: 0; width: 1px; height: 100%; }
.blueprint > .corner::after  { top: 5px; left: 0; width: 100%; height: 1px; }
.blueprint > .corner.tl { top: -6px; left: -6px; }
.blueprint > .corner.tr { top: -6px; right: -6px; }
.blueprint > .corner.bl { bottom: -6px; left: -6px; }
.blueprint > .corner.br { bottom: -6px; right: -6px; }

/* ══════ Components — built with the tokens above ══════ */

*, *::before, *::after { box-sizing: border-box; }
body { margin: 0; font-size: 15px; line-height: 1.55; font-weight: 400; }
h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-heading); font-weight: var(--font-heading-weight);
  line-height: 1.12; letter-spacing: -0.015em; margin: 0 0 var(--space-2);
}
h1 { font-size: 42px; }
h2 { font-size: 32px; }
h3 { font-size: 25px; }
h4 { font-size: 20px; }
h5 { font-size: 16px; }
h6 { font-size: 13px; }
h6 { letter-spacing: 0.08em; text-transform: uppercase; }
p { margin: 0 0 var(--space-3); }
a { color: var(--color-accent); text-underline-offset: 3px; }
img { display: block; max-width: 100%; }
figure { margin: 0; }
figcaption {
  font-size: 11px; margin-top: var(--space-1);
  color: color-mix(in srgb, var(--color-text) 55%, transparent);
}
:focus { outline: none; }
:focus-visible { outline: 2px solid var(--color-accent); outline-offset: 2px; }
::selection { background: color-mix(in srgb, var(--color-accent) 30%, transparent); }

/* — buttons — */
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 6px;
  cursor: pointer; text-decoration: none;
  font-family: var(--font-heading); font-weight: var(--font-heading-weight);
  font-size: 14px; line-height: 1.2; color: var(--color-text);
  background: transparent; border: 1px solid transparent;
  padding: var(--space-2) calc(var(--space-3) * 1.2);
}
.btn-primary { background: var(--color-accent); color: var(--color-bg); }
.btn-primary:hover { background: var(--color-accent-600); }
.btn-primary:active { background: var(--color-accent-700); }
.btn-secondary { border-color: var(--color-divider); }
.btn-secondary:hover { background: color-mix(in srgb, var(--color-text) 7%, transparent); }
.btn-secondary:active { background: color-mix(in srgb, var(--color-text) 14%, transparent); }

/* — tags — */
.tag {
  display: inline-flex; align-items: center; font-size: 11px;
  letter-spacing: 0.02em; padding: 3px 10px;
}
.tag-accent { background: var(--color-accent-100); color: var(--color-accent-800); }

/* — blueprint frame: nút vuông, viền mảnh — */
.btn { border: 1px solid var(--color-divider); }
.btn-primary { border-color: var(--color-accent); }