/* ============================================================
   REI Calc — Real Estate Calculator Suite
   Design system: deep navy surfaces + emerald accent (trust/finance)
   ============================================================ */

:root, [data-theme="light"] {
  /* Surfaces */
  --color-bg: #f5f7f8;
  --color-surface: #ffffff;
  --color-surface-2: #fbfcfc;
  --color-surface-offset: #eef1f3;
  --color-surface-offset-2: #e4e9ec;
  --color-divider: #dde3e7;
  --color-border: #d2d9dd;

  /* Text */
  --color-text: #0f1e2b;
  --color-text-muted: #566672;
  --color-text-faint: #9aa8b2;
  --color-text-inverse: #f5f7f8;

  /* Primary accent — emerald (money/growth) */
  --color-primary: #0a7d55;
  --color-primary-hover: #086445;
  --color-primary-active: #064c34;
  --color-primary-soft: #e3f2ec;

  /* Deep navy — headers, brand */
  --color-navy: #0f2e40;
  --color-navy-2: #14384f;

  /* Data / semantic */
  --color-gold: #b8860b;
  --color-blue: #1e6fa8;
  --color-error: #b23a48;
  --color-success: #0a7d55;

  --radius-sm: 0.375rem;
  --radius-md: 0.5rem;
  --radius-lg: 0.875rem;
  --radius-xl: 1.25rem;
  --radius-full: 9999px;

  --transition-interactive: 180ms cubic-bezier(0.16, 1, 0.3, 1);

  --shadow-sm: 0 1px 2px rgba(15, 46, 64, 0.06);
  --shadow-md: 0 6px 20px rgba(15, 46, 64, 0.09);
  --shadow-lg: 0 18px 48px rgba(15, 46, 64, 0.14);

  --content-narrow: 640px;
  --content-default: 1000px;
  --content-wide: 1240px;

  --font-display: 'Cabinet Grotesk', 'General Sans', system-ui, sans-serif;
  --font-body: 'General Sans', 'Inter', system-ui, sans-serif;

  --text-xs: clamp(0.75rem, 0.7rem + 0.25vw, 0.8125rem);
  --text-sm: clamp(0.875rem, 0.8rem + 0.35vw, 0.9375rem);
  --text-base: clamp(1rem, 0.95rem + 0.25vw, 1.0625rem);
  --text-lg: clamp(1.125rem, 1rem + 0.6vw, 1.375rem);
  --text-xl: clamp(1.5rem, 1.2rem + 1.1vw, 2.1rem);
  --text-2xl: clamp(2rem, 1.3rem + 2.4vw, 3.25rem);

  --space-1: 0.25rem; --space-2: 0.5rem; --space-3: 0.75rem; --space-4: 1rem;
  --space-5: 1.25rem; --space-6: 1.5rem; --space-8: 2rem; --space-10: 2.5rem;
  --space-12: 3rem; --space-16: 4rem; --space-20: 5rem; --space-24: 6rem;
}

[data-theme="dark"] {
  --color-bg: #0a141b;
  --color-surface: #10202b;
  --color-surface-2: #14283440;
  --color-surface-offset: #16303e;
  --color-surface-offset-2: #1d3c4d;
  --color-divider: #1e3644;
  --color-border: #274454;
  --color-text: #dce6ec;
  --color-text-muted: #8aa0ae;
  --color-text-faint: #5a7180;
  --color-text-inverse: #0a141b;
  --color-primary: #2ecb8b;
  --color-primary-hover: #4cd89d;
  --color-primary-active: #6fe3b1;
  --color-primary-soft: #123329;
  --color-navy: #0d1f2b;
  --color-navy-2: #12293800;
  --color-gold: #d9a92e;
  --color-blue: #4f9fd4;
  --color-error: #e07685;
  --color-success: #2ecb8b;
  --shadow-sm: 0 1px 2px rgba(0,0,0,0.3);
  --shadow-md: 0 6px 20px rgba(0,0,0,0.4);
  --shadow-lg: 0 18px 48px rgba(0,0,0,0.55);
}

@media (prefers-color-scheme: dark) {
  :root:not([data-theme]) {
    --color-bg: #0a141b; --color-surface: #10202b; --color-surface-2: #14283440;
    --color-surface-offset: #16303e; --color-surface-offset-2: #1d3c4d;
    --color-divider: #1e3644; --color-border: #274454; --color-text: #dce6ec;
    --color-text-muted: #8aa0ae; --color-text-faint: #5a7180; --color-text-inverse: #0a141b;
    --color-primary: #2ecb8b; --color-primary-hover: #4cd89d; --color-primary-active: #6fe3b1;
    --color-primary-soft: #123329; --color-navy: #0d1f2b; --color-gold: #d9a92e;
    --color-blue: #4f9fd4; --color-error: #e07685; --color-success: #2ecb8b;
  }
}

/* ---------------- Base ---------------- */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html {
  -webkit-text-size-adjust: none; text-size-adjust: none;
  -webkit-font-smoothing: antialiased; -moz-osx-font-smoothing: grayscale;
  text-rendering: optimizeLegibility; scroll-behavior: smooth;
  scroll-padding-top: 5rem;
}
body {
  min-height: 100dvh; line-height: 1.6; font-family: var(--font-body);
  font-size: var(--text-base); color: var(--color-text);
  background: var(--color-bg);
}
img, svg { display: block; max-width: 100%; height: auto; }
input, button, select { font: inherit; color: inherit; }
h1,h2,h3,h4 { text-wrap: balance; line-height: 1.12; font-family: var(--font-display); font-weight: 700; letter-spacing: -0.01em; }
p { text-wrap: pretty; }
button { cursor: pointer; background: none; border: none; }
a { color: inherit; text-decoration: none; }
::selection { background: color-mix(in oklab, var(--color-primary) 25%, transparent); }
:focus-visible { outline: 2px solid var(--color-primary); outline-offset: 3px; border-radius: var(--radius-sm); }
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { animation-duration: .01ms !important; transition-duration: .01ms !important; scroll-behavior: auto !important; }
}
a, button, input, select { transition: color var(--transition-interactive), background var(--transition-interactive), border-color var(--transition-interactive), box-shadow var(--transition-interactive), transform var(--transition-interactive); }
.sr-only { position: absolute; width: 1px; height: 1px; padding: 0; margin: -1px; overflow: hidden; clip: rect(0,0,0,0); white-space: nowrap; }

.wrap { width: 100%; max-width: var(--content-wide); margin-inline: auto; padding-inline: var(--space-5); }

/* ---------------- Header ---------------- */
.site-header {
  position: sticky; top: 0; z-index: 50;
  background: color-mix(in oklab, var(--color-bg) 82%, transparent);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--color-divider);
}
.header-inner { display: flex; align-items: center; justify-content: space-between; gap: var(--space-4); height: 4.25rem; }
.brand { display: flex; align-items: center; gap: var(--space-3); font-family: var(--font-display); font-weight: 700; font-size: 1.1rem; color: var(--color-text); letter-spacing: -0.02em; }
.brand svg { color: var(--color-primary); flex-shrink: 0; }
.brand span b { color: var(--color-primary); }
.header-nav { display: flex; align-items: center; gap: var(--space-2); }
.nav-select { display: none; }
.theme-toggle { display: grid; place-items: center; width: 2.4rem; height: 2.4rem; border-radius: var(--radius-full); color: var(--color-text-muted); border: 1px solid var(--color-border); }
.theme-toggle:hover { color: var(--color-primary); border-color: var(--color-primary); }

/* ---------------- Hero ---------------- */
.hero { padding-block: clamp(var(--space-12), 7vw, var(--space-24)) var(--space-10); text-align: center; position: relative; overflow: hidden; }
.hero::before {
  content: ""; position: absolute; inset: 0; z-index: -1;
  background: radial-gradient(ellipse 70% 55% at 50% -10%, color-mix(in oklab, var(--color-primary) 16%, transparent), transparent 70%);
}
.hero .eyebrow { display: inline-flex; align-items: center; gap: var(--space-2); font-size: var(--text-xs); font-weight: 600; text-transform: uppercase; letter-spacing: 0.09em; color: var(--color-primary); background: var(--color-primary-soft); padding: var(--space-2) var(--space-4); border-radius: var(--radius-full); margin-bottom: var(--space-5); }
.hero h1 { font-size: var(--text-2xl); max-width: 16ch; margin-inline: auto; }
.hero h1 em { font-style: normal; color: var(--color-primary); }
.hero p { max-width: 56ch; margin: var(--space-5) auto 0; color: var(--color-text-muted); font-size: var(--text-lg); }
.hero-stats { display: flex; flex-wrap: wrap; justify-content: center; gap: var(--space-8); margin-top: var(--space-10); }
.hero-stat b { display: block; font-family: var(--font-display); font-size: var(--text-xl); color: var(--color-text); }
.hero-stat span { font-size: var(--text-xs); text-transform: uppercase; letter-spacing: 0.06em; color: var(--color-text-faint); }

/* ---------------- Section ---------------- */
.section { padding-block: var(--space-16); }
.section-head { max-width: 60ch; margin-bottom: var(--space-10); }
.section-head h2 { font-size: var(--text-xl); }
.section-head p { color: var(--color-text-muted); margin-top: var(--space-3); }

/* ---------------- Calculator grid ---------------- */
.calc-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(250px, 1fr)); gap: var(--space-4); }
.calc-card {
  text-align: left; padding: var(--space-6); border-radius: var(--radius-lg);
  background: var(--color-surface); border: 1px solid var(--color-border);
  box-shadow: var(--shadow-sm); display: flex; flex-direction: column; gap: var(--space-3);
  width: 100%;
}
.calc-card:hover { transform: translateY(-3px); box-shadow: var(--shadow-md); border-color: color-mix(in oklab, var(--color-primary) 45%, var(--color-border)); }
.calc-card .ic { width: 2.6rem; height: 2.6rem; border-radius: var(--radius-md); display: grid; place-items: center; background: var(--color-primary-soft); color: var(--color-primary); }
.calc-card .cat { font-size: var(--text-xs); font-weight: 600; text-transform: uppercase; letter-spacing: 0.06em; color: var(--color-gold); }
.calc-card h3 { font-size: var(--text-base); font-family: var(--font-display); }
.calc-card p { font-size: var(--text-sm); color: var(--color-text-muted); line-height: 1.5; }
.calc-card .go { margin-top: auto; font-size: var(--text-sm); font-weight: 600; color: var(--color-primary); display: inline-flex; align-items: center; gap: var(--space-2); }

/* ---------------- Calculator view ---------------- */
.calc-view { display: none; }
.calc-view.active { display: block; }

/* ---------------- Content pages (About / Contact / Privacy) ---------------- */
.page-view { display: none; }
.page-view.active { display: block; }
.prose { max-width: 68ch; margin: 0 auto; padding-bottom: var(--space-10); }
.prose h1 { font-family: var(--font-display); font-size: var(--text-2xl); line-height: 1.15; margin-bottom: var(--space-4); }
.prose h2 { font-family: var(--font-display); font-size: var(--text-lg); margin-top: var(--space-8); margin-bottom: var(--space-3); }
.prose p { color: var(--color-text); line-height: 1.7; margin-bottom: var(--space-4); }
.prose .lead { font-size: var(--text-base); color: var(--color-text-muted); line-height: 1.65; margin-bottom: var(--space-6); }
.prose ul { margin: 0 0 var(--space-4) var(--space-5); padding: 0; }
.prose li { color: var(--color-text); line-height: 1.7; margin-bottom: var(--space-2); list-style: disc; }
.prose a { color: var(--color-primary); font-weight: 500; text-decoration: underline; text-underline-offset: 2px; }
.prose a:hover { opacity: .8; }
.prose em { font-style: italic; }
.contact-email { display: inline-block; font-family: var(--font-display); font-size: var(--text-lg); color: var(--color-primary); text-decoration: none !important; }
.home.hidden { display: none; }
.hidden { display: none !important; }
.back-link { display: inline-flex; align-items: center; gap: var(--space-2); font-size: var(--text-sm); color: var(--color-text-muted); font-weight: 500; margin-bottom: var(--space-6); }
.back-link:hover { color: var(--color-primary); }

/* ---------- blog / guides ---------- */
.blog-head { max-width: 60ch; margin-bottom: var(--space-8); }
.blog-head h1 { font-family: var(--font-display); font-size: var(--text-2xl); line-height: 1.15; margin-bottom: var(--space-3); }
.blog-head p { color: var(--color-text-muted); font-size: var(--text-base); line-height: 1.6; }
.post-grid { display: grid; grid-template-columns: 1fr; gap: var(--space-5); }
@media (min-width: 720px) { .post-grid { grid-template-columns: 1fr 1fr; } }
@media (min-width: 1040px) { .post-grid { grid-template-columns: repeat(3, 1fr); } }
.post-card { display: flex; flex-direction: column; gap: var(--space-2); background: var(--color-surface); border: 1px solid var(--color-border); border-radius: var(--radius-lg); padding: var(--space-6); box-shadow: var(--shadow-sm); text-decoration: none; transition: transform .15s ease, box-shadow .15s ease, border-color .15s ease; }
.post-card:hover { transform: translateY(-3px); box-shadow: var(--shadow-md); border-color: var(--color-primary); }
.post-card h3 { font-family: var(--font-display); font-size: var(--text-lg); line-height: 1.2; color: var(--color-text); margin: var(--space-1) 0; }
.post-card p { color: var(--color-text-muted); font-size: var(--text-sm); line-height: 1.55; flex: 1; }
.post-meta { color: var(--color-text-muted); font-size: var(--text-xs); margin-top: var(--space-2); }
.post-tag { align-self: flex-start; display: inline-block; font-size: var(--text-xs); font-weight: 600; letter-spacing: .04em; text-transform: uppercase; color: var(--color-primary); background: color-mix(in srgb, var(--color-primary) 12%, transparent); border-radius: 999px; padding: 2px 10px; }
.article { max-width: 72ch; }
.article .post-tag { margin-bottom: var(--space-3); }
.article-meta { color: var(--color-text-muted); font-size: var(--text-sm); margin-bottom: var(--space-6) !important; }
.article h3 { font-family: var(--font-display); font-size: var(--text-base); margin-top: var(--space-6); margin-bottom: var(--space-2); }
.article-cta { margin-top: var(--space-10); padding: var(--space-6); background: var(--color-surface); border: 1px solid var(--color-border); border-radius: var(--radius-lg); text-align: center; }
.article-cta p { font-family: var(--font-display); font-size: var(--text-lg); margin-bottom: var(--space-4) !important; }

.calc-header { margin-bottom: var(--space-8); }
.calc-header h1 { font-size: var(--text-xl); }
.calc-header p { color: var(--color-text-muted); margin-top: var(--space-2); max-width: 62ch; }

.calc-layout { display: grid; grid-template-columns: 1fr; gap: var(--space-6); align-items: start; }
@media (min-width: 860px) { .calc-layout { grid-template-columns: 1.15fr 1fr; gap: var(--space-8); } }

.calc-panel { background: var(--color-surface); border: 1px solid var(--color-border); border-radius: var(--radius-lg); padding: var(--space-6); box-shadow: var(--shadow-sm); }
.calc-panel h2 { font-size: var(--text-base); font-family: var(--font-display); margin-bottom: var(--space-5); padding-bottom: var(--space-3); border-bottom: 1px solid var(--color-divider); }

.field { margin-bottom: var(--space-5); }
.field label { display: flex; justify-content: space-between; align-items: baseline; font-size: var(--text-sm); font-weight: 500; margin-bottom: var(--space-2); }
.field label .hint { color: var(--color-text-faint); font-weight: 400; font-size: var(--text-xs); }
.input-wrap { position: relative; display: flex; align-items: center; }
.input-wrap .affix { position: absolute; color: var(--color-text-faint); font-size: var(--text-sm); pointer-events: none; }
.input-wrap .affix.pre { left: var(--space-3); }
.input-wrap .affix.post { right: var(--space-3); }
.field input, .field select {
  width: 100%; padding: var(--space-3) var(--space-4); border-radius: var(--radius-md);
  border: 1px solid var(--color-border); background: var(--color-bg); color: var(--color-text);
  font-size: var(--text-base); font-variant-numeric: tabular-nums;
}
.field input.has-pre { padding-left: var(--space-8); }
.field input.has-post { padding-right: 3rem; }
.field input:focus, .field select:focus { border-color: var(--color-primary); box-shadow: 0 0 0 3px var(--color-primary-soft); outline: none; }
.field select { appearance: none; cursor: pointer; background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='16' height='16' viewBox='0 0 24 24' fill='none' stroke='%2364748b' stroke-width='2' stroke-linecap='round' stroke-linejoin='round'%3E%3Cpath d='M6 9l6 6 6-6'/%3E%3C/svg%3E"); background-repeat: no-repeat; background-position: right var(--space-4) center; padding-right: var(--space-8); }
.field input[type="date"] { cursor: pointer; }
[data-theme="dark"] .field input[type="date"]::-webkit-calendar-picker-indicator { filter: invert(0.7); }
.field-row { display: grid; grid-template-columns: 1fr 1fr; gap: var(--space-4); }

/* Results */
.results { position: sticky; top: 5.5rem; }
.result-hero { background: linear-gradient(150deg, var(--color-navy), var(--color-navy-2)); color: #fff; border-radius: var(--radius-lg); padding: var(--space-8) var(--space-6); text-align: center; box-shadow: var(--shadow-md); }
[data-theme="dark"] .result-hero { border: 1px solid var(--color-border); }
.result-hero .label { font-size: var(--text-xs); text-transform: uppercase; letter-spacing: 0.09em; color: rgba(255,255,255,0.65); }
.result-hero .value { font-family: var(--font-display); font-size: clamp(2.2rem, 1.4rem + 3vw, 3.4rem); font-weight: 700; margin-top: var(--space-2); letter-spacing: -0.02em; color: #fff; font-variant-numeric: tabular-nums; }
.result-hero .value.pos { color: #4cd89d; }
.result-hero .value.neg { color: #ff9ba6; }
.result-hero .sub { font-size: var(--text-sm); color: rgba(255,255,255,0.7); margin-top: var(--space-2); }
.result-rows { margin-top: var(--space-5); background: var(--color-surface); border: 1px solid var(--color-border); border-radius: var(--radius-lg); overflow: hidden; }
.result-row { display: flex; justify-content: space-between; align-items: center; gap: var(--space-4); padding: var(--space-4) var(--space-5); border-bottom: 1px solid var(--color-divider); font-size: var(--text-sm); }
.result-row:last-child { border-bottom: none; }
.result-row .k { color: var(--color-text-muted); }
.result-row .v { font-weight: 600; font-variant-numeric: tabular-nums; }
.result-row.total { background: var(--color-surface-offset); font-size: var(--text-base); }
.result-row.total .v { color: var(--color-primary); }
.verdict { margin-top: var(--space-4); padding: var(--space-4) var(--space-5); border-radius: var(--radius-md); font-size: var(--text-sm); display: flex; gap: var(--space-3); align-items: flex-start; }
.verdict.good { background: var(--color-primary-soft); color: var(--color-primary-hover); }
.verdict.warn { background: color-mix(in oklab, var(--color-gold) 16%, transparent); color: var(--color-gold); }
.verdict.bad { background: color-mix(in oklab, var(--color-error) 14%, transparent); color: var(--color-error); }
[data-theme="dark"] .verdict.good { color: var(--color-primary); }

.explainer { margin-top: var(--space-12); max-width: 68ch; }
.explainer h2 { font-size: var(--text-lg); margin-bottom: var(--space-4); }
.explainer h3 { font-size: var(--text-base); margin: var(--space-6) 0 var(--space-2); font-family: var(--font-display); }
.explainer p { color: var(--color-text-muted); margin-bottom: var(--space-3); }
.explainer .formula, .article .formula { background: var(--color-surface-offset); border-left: 3px solid var(--color-primary); padding: var(--space-4) var(--space-5); border-radius: var(--radius-md); font-family: ui-monospace, 'SF Mono', Menlo, monospace; font-size: var(--text-sm); color: var(--color-text); margin: var(--space-3) 0; }

/* Ad slots */
.ad-slot { max-width: var(--content-default); margin: var(--space-8) auto; padding: var(--space-6); border: 1px dashed var(--color-border); border-radius: var(--radius-md); text-align: center; color: var(--color-text-faint); font-size: var(--text-xs); text-transform: uppercase; letter-spacing: 0.08em; background: var(--color-surface-2); }

/* Chart */
.chart-wrap { margin-top: var(--space-5); background: var(--color-surface); border: 1px solid var(--color-border); border-radius: var(--radius-lg); padding: var(--space-5); }
.chart-title { font-size: var(--text-xs); text-transform: uppercase; letter-spacing: 0.08em; color: var(--color-text-faint); margin-bottom: var(--space-3); }
.chart-wrap canvas { width: 100%; display: block; }
.chart-legend { display: flex; flex-wrap: wrap; gap: var(--space-4); margin-top: var(--space-3); font-size: var(--text-xs); color: var(--color-text-muted); }
.chart-legend .lg { display: inline-flex; align-items: center; gap: var(--space-2); }
.chart-legend .lg i { width: 12px; height: 12px; border-radius: 3px; display: inline-block; }

/* Footer */
.site-footer { border-top: 1px solid var(--color-divider); margin-top: var(--space-20); padding-block: var(--space-12) var(--space-8); }
.footer-grid { display: grid; grid-template-columns: 1fr; gap: var(--space-8); }
@media (min-width: 640px) { .footer-grid { grid-template-columns: 1fr 1fr; } }
@media (min-width: 900px) { .footer-grid { grid-template-columns: 1.6fr 1fr 1fr 1fr 1fr; } }
.footer-grid h4 { font-size: var(--text-xs); text-transform: uppercase; letter-spacing: 0.08em; color: var(--color-text-faint); margin-bottom: var(--space-4); }
.footer-links { display: flex; flex-direction: column; gap: var(--space-2); }
.footer-links button, .footer-links a { text-align: left; font-size: var(--text-sm); color: var(--color-text-muted); }
.footer-links button:hover, .footer-links a:hover { color: var(--color-primary); }
.footer-legal-row { display: flex; flex-wrap: wrap; gap: var(--space-5); margin-top: var(--space-10); padding-top: var(--space-6); border-top: 1px solid var(--color-divider); }
.footer-legal-row button { font-size: var(--text-sm); font-weight: 500; color: var(--color-text-muted); }
.footer-legal-row button:hover { color: var(--color-primary); }
.footer-note { margin-top: var(--space-5); font-size: var(--text-xs); color: var(--color-text-faint); max-width: 90ch; }

.disclaimer { font-size: var(--text-xs); color: var(--color-text-faint); margin-top: var(--space-4); }