/* Shared styles for all calculators: theme tokens, layout, inputs, cards, tables, tabs */
:root{
  color-scheme: light;
  --bg:#f6f6f4; --surface:#fcfcfb; --border:#e3e2de; --text:#0b0b0b; --text2:#52514e; --muted:#6f6e69;
  --s1:#2a78d6; --s2:#eb6834; --s3:#1baf7a; --s4:#eda100; --grey:#c9c8c3; --grey2:#9f9e99;
  --good:#1a7f37; --warn:#b26b00; --bad:#c62828;
  --brand:#0e7c57; --brand-ink:#0b6b4a;   /* Othman Energy Lab green: fills / text and links */
}
@media (prefers-color-scheme: dark){
  :root:where(:not([data-theme="light"])){
    color-scheme: dark;
    --bg:#121211; --surface:#1a1a19; --border:#2e2e2c; --text:#f0efec; --text2:#c3c2b7; --muted:#8f8e88;
    --s1:#3987e5; --s2:#d95926; --s3:#199e70; --s4:#c98500; --grey:#4a4a47; --grey2:#6c6b67;
    --good:#4cc26a; --warn:#e0a03a; --bad:#ef6b6b;
    --brand:#17855e; --brand-ink:#4cc99a;
  }
}
*{box-sizing:border-box}
:root{--navh:58px;--maxw:1180px}
html{scroll-padding-top:calc(var(--navh) + 12px)}
body{margin:0;background:var(--bg);color:var(--text);font:14px/1.45 system-ui,-apple-system,"Segoe UI",Roboto,sans-serif}
.pagehead{padding:20px 28px 8px}
.pagehead h1{font-size:24px;margin:2px 0 4px;letter-spacing:-.01em}
.crumbs{font-size:12.5px;color:var(--muted)}
.crumbs a{color:var(--text2);text-decoration:none}
.crumbs a:hover{color:var(--brand-ink)}
.chips{display:flex;flex-wrap:wrap;gap:6px;margin-top:10px}
.chips span{font-size:11.5px;color:var(--text2);border:1px solid var(--border);border-radius:10px;padding:1px 8px;background:var(--surface)}
h1{font-size:22px;margin:0 0 4px}
.sub{color:var(--text2);margin:0}
main.layout{display:grid;grid-template-columns:340px minmax(0,1fr);gap:18px;padding:12px 28px 40px;align-items:start}
@media (max-width:900px){main.layout{grid-template-columns:minmax(0,1fr);padding:12px 16px 40px}.pagehead{padding:18px 16px 6px}}
.card{background:var(--surface);border:1px solid var(--border);border-radius:10px;padding:16px}
.card h2{font-size:15px;margin:0 0 10px}
.card h3{font-size:12px;margin:14px 0 4px;color:var(--text2);text-transform:uppercase;letter-spacing:.04em}
label{display:block;font-size:12.5px;color:var(--text2);margin:8px 0 3px}
input[type=number],select{width:100%;padding:7px 8px;border:1px solid var(--border);border-radius:6px;background:var(--bg);color:var(--text);font:inherit}
.row{display:grid;grid-template-columns:1fr 1fr;gap:8px}
.row3{display:grid;grid-template-columns:1fr 1fr 1fr;gap:8px}
.tabs{display:flex;gap:6px;margin-bottom:6px}
.tabs button,.seg button{flex:1;padding:7px;border:1px solid var(--border);background:var(--bg);color:var(--text);border-radius:6px;cursor:pointer;font:inherit}
.tabs button.on,.seg button.on{background:var(--brand);color:#fff;border-color:var(--brand)}
.seg{display:inline-flex;gap:4px;margin-bottom:8px}.seg button{padding:4px 12px;font-size:12.5px;white-space:nowrap}
.drop{border:1.5px dashed var(--border);border-radius:8px;padding:14px;text-align:center;color:var(--text2);cursor:pointer}
.drop:hover{border-color:var(--brand)}
input[type=range]{width:100%}
.rng{display:grid;grid-template-columns:1fr 26px;align-items:center;gap:6px}
.rng span{text-align:right;font-variant-numeric:tabular-nums}
.note{font-size:12px;color:var(--muted);margin-top:6px}
details summary{cursor:pointer;color:var(--text2);font-size:13px;margin-top:12px}
.kpis{display:grid;grid-template-columns:repeat(4,1fr);gap:10px;margin-top:12px}
@media (max-width:700px){.kpis{grid-template-columns:repeat(2,1fr)}}
.kpi{background:var(--bg);border-radius:8px;padding:10px}
.kpi .v{font-size:19px;font-weight:650;font-variant-numeric:tabular-nums}
.kpi .l{font-size:12px;color:var(--text2)}
table{width:100%;border-collapse:collapse;font-variant-numeric:tabular-nums;font-size:13px}
th,td{padding:7px 8px;border-bottom:1px solid var(--border);text-align:right;white-space:nowrap}
th:first-child,td:first-child,td.l,th.l{text-align:left;white-space:normal}
th{color:var(--text2);font-weight:600;font-size:12px}
tr.best td{font-weight:650}
.tag{display:inline-block;font-size:11px;padding:1px 6px;border-radius:10px;margin-left:6px;font-weight:600}
.tag.ok{background:color-mix(in srgb,var(--good) 15%,transparent);color:var(--good)}
.tag.x{background:color-mix(in srgb,var(--bad) 15%,transparent);color:var(--bad)}
.split{display:grid;grid-template-columns:1.15fr 1fr;gap:16px;align-items:start}
@media (max-width:1150px){.split{grid-template-columns:1fr}}
.grid2{display:grid;grid-template-columns:1fr 1fr;gap:18px}
@media (max-width:1100px){.grid2{grid-template-columns:1fr}}
.chartbox{position:relative;height:250px}
.banner{font-size:12.5px;padding:8px 10px;border-radius:6px;background:color-mix(in srgb,var(--warn) 14%,transparent);color:var(--text);margin-bottom:10px}
.err{color:var(--bad);font-size:12.5px;margin-top:6px}
.legend{display:flex;flex-wrap:wrap;gap:14px;font-size:12px;color:var(--text2);margin:-2px 0 8px}
.legend i{display:inline-block;width:10px;height:10px;border-radius:2px;margin-right:5px;vertical-align:-1px}
.method{font-size:12.5px;color:var(--text2)}
.method li{margin:4px 0}
.method code{font-size:12px;background:var(--bg);padding:1px 4px;border-radius:4px}
.ctitle{font-size:13px;font-weight:600;margin:0 0 6px}
/* results tabs */
.rtabs{display:flex;flex-wrap:wrap;gap:4px;padding:4px;background:var(--surface);border:1px solid var(--border);border-radius:10px;position:sticky;top:calc(var(--navh) + env(safe-area-inset-top,0px));z-index:5}
.rtabs button{flex:1 1 auto;border:0;background:none;padding:8px 14px;border-radius:7px;font:inherit;font-weight:500;color:var(--text2);cursor:pointer;white-space:nowrap}
.rtabs button:hover{background:var(--bg);color:var(--text)}
.rtabs button.on{background:var(--brand);color:#fff;font-weight:600}
.rtabs button:focus-visible{outline:2px solid var(--brand);outline-offset:2px}
.pane{display:grid;grid-template-columns:minmax(0,1fr);gap:18px}
.pane[hidden]{display:none}
button.link{border:1px solid var(--brand-ink);background:none;color:var(--brand-ink);border-radius:6px;padding:6px 12px;font:inherit;font-weight:600;cursor:pointer}
button.link:hover{background:color-mix(in srgb,var(--brand) 10%,transparent)}
tr.click{cursor:pointer}
tr.click:hover td{background:color-mix(in srgb,var(--text) 4%,transparent)}
td.hi{background:color-mix(in srgb,var(--brand) 13%,transparent);font-weight:650}
.tag:not(.ok):not(.x){background:var(--bg);color:var(--text2);border:1px solid var(--border)}
/* site bar, footer, buttons (shared/js/site.js fills the bar and footer) */
.sitebar{position:sticky;top:0;z-index:20;background:color-mix(in srgb,var(--surface) 90%,transparent);backdrop-filter:blur(10px);border-bottom:1px solid var(--border);padding-top:env(safe-area-inset-top,0px)}
.sitebar-in{max-width:var(--maxw);margin:0 auto;height:var(--navh);display:flex;align-items:center;justify-content:space-between;gap:16px;padding:0 28px}
.brand{display:flex;align-items:center;gap:9px;color:var(--text);text-decoration:none;font-weight:650;font-size:15.5px;letter-spacing:-.015em;white-space:nowrap}
.brand b{color:var(--brand-ink);font-weight:750}
.brand svg{width:26px;height:26px;display:block}
.sitebar nav{display:flex;gap:2px;overflow-x:auto}
.sitebar nav a{color:var(--text2);text-decoration:none;padding:7px 11px;border-radius:7px;font-weight:500;white-space:nowrap}
.sitebar nav a:hover{color:var(--text);background:var(--bg)}
.sitebar nav a[aria-current]{color:var(--text);background:var(--bg);font-weight:600}
.sitefoot{border-top:1px solid var(--border);margin-top:32px;color:var(--muted);font-size:12.5px}
.sitefoot-in{max-width:var(--maxw);margin:0 auto;padding:28px 28px calc(28px + env(safe-area-inset-bottom,0px));display:flex;flex-wrap:wrap;justify-content:space-between;align-items:flex-start;gap:16px 32px}
.sitefoot .fb{display:flex;align-items:center;gap:8px;color:var(--text);font-weight:650;font-size:14px}
.sitefoot .fb svg{width:22px;height:22px}
.sitefoot .ft{margin-top:4px;color:var(--text2)}
.sitefoot nav{display:flex;flex-wrap:wrap;gap:6px 18px}
.sitefoot .fn{flex-basis:100%;padding-top:14px;border-top:1px solid var(--border)}
.sitefoot a{color:var(--text2);text-decoration:none}
.sitefoot a:hover{color:var(--brand-ink)}
.btn{display:inline-flex;align-items:center;gap:6px;padding:10px 16px;border-radius:8px;border:1px solid var(--border);background:var(--surface);color:var(--text);text-decoration:none;font-weight:600;font-size:14px}
.btn:hover{border-color:var(--brand)}
.btn.primary{background:var(--brand);border-color:var(--brand);color:#fff}
.btn.primary:hover{background:color-mix(in srgb,var(--brand) 88%,#000)}
body.wide{--maxw:none}
@media (max-width:900px){.sitebar-in,.sitefoot-in{padding-left:16px;padding-right:16px}}
@media (max-width:560px){.brand .bn{display:none}.sitebar nav a{padding:7px 8px}}
/* site pages (home, focus areas): sections and tool cards */
.wrap{max-width:var(--maxw);margin:0 auto;padding:0 28px}
@media (max-width:900px){.wrap{padding:0 16px}}
.wrap>section{padding:56px 0 8px}
.eyebrow{font-size:12.5px;font-weight:650;letter-spacing:.06em;text-transform:uppercase;color:var(--brand-ink);margin:0 0 10px}
.shead{max-width:70ch;margin-bottom:22px}
.shead h2{font-size:26px;letter-spacing:-.015em;margin:0 0 8px}
.shead p{color:var(--text2);margin:0;font-size:15px}
.shead p.eyebrow{color:var(--brand-ink);font-size:12.5px;margin-bottom:10px}
.tools{display:grid;grid-template-columns:repeat(auto-fill,minmax(320px,1fr));gap:16px}
a.tool{display:flex;flex-direction:column;gap:10px;color:inherit;text-decoration:none;padding:20px;transition:border-color .15s}
a.tool:hover{border-color:var(--brand)}
a.tool .top{display:flex;justify-content:space-between;align-items:center;gap:8px}
a.tool .top .tag{margin-left:0}
a.tool .area{font-size:12px;color:var(--muted)}
a.tool h3{margin:0;font-size:18px;letter-spacing:-.01em;color:var(--text);text-transform:none}
a.tool p{margin:0;color:var(--text2)}
a.tool .chips{margin-top:auto}
a.tool .open{color:var(--brand-ink);font-weight:600;font-size:13.5px}
.soon{border-style:dashed;color:var(--muted);display:flex;flex-direction:column;align-items:center;justify-content:center;gap:4px;min-height:180px;text-align:center;padding:20px}
.soon b{color:var(--text2)}
/* motion: short and subtle; switched off when the visitor prefers reduced motion */
html{scroll-behavior:smooth}
a,button,.btn,.card,.tag,input,select{transition:background-color .18s ease,border-color .18s ease,color .18s ease,box-shadow .18s ease,transform .18s ease}
.btn:hover,button.link:hover{transform:translateY(-1px)}
a.tool:hover,a.areac:hover,tr.click:hover{box-shadow:0 8px 22px color-mix(in srgb,var(--text) 9%,transparent)}
a.tool:hover,a.areac:hover{transform:translateY(-2px)}
input:focus-visible,select:focus-visible{outline:none;border-color:var(--brand);box-shadow:0 0 0 3px color-mix(in srgb,var(--brand) 22%,transparent)}
.pane:not([hidden]){animation:fadeUp .24s ease both}
@keyframes fadeUp{from{opacity:0;transform:translateY(6px)}to{opacity:1;transform:none}}
details summary{list-style:none;display:flex;align-items:center;gap:8px;user-select:none}
details summary::-webkit-details-marker{display:none}
details summary::before{content:"";flex:none;width:6px;height:6px;border-right:1.6px solid currentColor;border-bottom:1.6px solid currentColor;transform:rotate(-45deg);transition:transform .2s ease}
details[open] summary::before{transform:rotate(45deg)}
details summary:hover{color:var(--text)}
details[open]>:not(summary){animation:fadeUp .2s ease both}
.sitebar{transition:box-shadow .2s ease}
.sitebar.scrolled{box-shadow:0 2px 14px color-mix(in srgb,#000 10%,transparent)}
@media (prefers-reduced-motion:reduce){html{scroll-behavior:auto}*,*::before,*::after{animation:none!important;transition:none!important}}
/* company pages: vision and mission, values, approach steps, standards (home, about, contact) */
.vm{display:grid;grid-template-columns:1fr 1fr;gap:16px}
@media (max-width:900px){.vm{grid-template-columns:1fr}}
.vmc{padding:26px;border-left:4px solid var(--brand)}
.vml{display:block;font-size:12.5px;font-weight:700;letter-spacing:.06em;text-transform:uppercase;color:var(--brand-ink);margin-bottom:10px}
.vmc p{margin:0;font-size:18px;line-height:1.5;letter-spacing:-.005em;color:var(--text)}
.values{display:grid;grid-template-columns:repeat(3,1fr);gap:16px;margin-top:16px}
@media (max-width:900px){.values{grid-template-columns:1fr}}
.values div{display:flex;flex-direction:column;gap:4px;padding:4px 2px 4px 14px;border-left:2px solid var(--border)}
.values b{font-size:14.5px}
.values span{color:var(--text2)}
/* approach */
.steps{display:grid;grid-template-columns:repeat(4,1fr);gap:16px}
@media (max-width:1100px){.steps{grid-template-columns:1fr 1fr}}
@media (max-width:640px){.steps{grid-template-columns:1fr}}
.step{padding:22px}
.step .n{display:inline-flex;width:28px;height:28px;border-radius:7px;align-items:center;justify-content:center;font-weight:700;font-size:13px;color:#fff;background:var(--brand);margin-bottom:12px}
.step h3{margin:0 0 6px;font-size:16px;color:var(--text);text-transform:none;letter-spacing:-.01em}
.step p{margin:0;color:var(--text2)}
/* standards */
.stds{display:grid;grid-template-columns:repeat(auto-fill,minmax(300px,1fr));gap:12px}
.std{padding:16px 18px;display:flex;flex-direction:column;gap:4px}
.std .h{display:flex;justify-content:space-between;align-items:baseline;gap:10px}
.std b{font-size:14.5px}
.std p{margin:0;color:var(--text2);font-size:13px}
.std .tag{margin-left:0;white-space:nowrap}
/* goals */
.goals{display:grid;grid-template-columns:repeat(3,1fr);gap:16px}
@media (max-width:1000px){.goals{grid-template-columns:1fr 1fr}}
@media (max-width:640px){.goals{grid-template-columns:1fr}}
.goal{padding:22px;position:relative;overflow:hidden}
.goal::before{content:"";position:absolute;left:0;top:0;right:0;height:3px;background:var(--brand);transform:scaleX(.18);transform-origin:left;transition:transform .3s ease}
.goal:hover::before{transform:scaleX(1)}
.goal .gn{display:block;font-size:13px;font-weight:700;letter-spacing:.06em;color:var(--brand-ink);margin-bottom:10px;font-variant-numeric:tabular-nums}
.goal h3{margin:0 0 6px;font-size:18px;letter-spacing:-.01em;color:var(--text);text-transform:none}
.goal p{margin:0;color:var(--text2)}
.toolsnote{margin-top:16px;padding:14px 18px;border-radius:10px;border:1px dashed color-mix(in srgb,var(--brand) 45%,var(--border));background:color-mix(in srgb,var(--brand) 6%,var(--bg));color:var(--text2)}
.toolsnote b{color:var(--text)}
.toolsnote a{color:var(--brand-ink);font-weight:600}
/* top-bar tagline: quiet grey text right next to the logo (page links are in the footer) */
.sitebar-in{justify-content:flex-start}
.slogan{margin:0;padding-left:14px;border-left:1px solid var(--border);display:flex;flex-wrap:wrap;gap:0 6px;font-size:13.5px;font-weight:400;color:var(--muted);line-height:1.3}
@media (max-width:700px){.slogan{font-size:12.5px;padding-left:10px}}
@media (max-width:380px){.slogan span:last-child{display:none}}