/* IB MYP Chemistry notes — base stylesheet.
   Extracted unchanged from the <style> block repeated in every MYP page.
   The URstudymate design layer (urstudymate.css) loads after it. */
:root{--paper:#fffdf7;--ivory:#f6f2e8;--ink:#283347;--indigo:#303a70;--teal:#165e59;--teal-bg:#e4f2ee;--lavender:#f0ecf8;--line:#d6d3c8;--muted:#536075;--purple:#583881;
--cA:#2d5fa8;--cA-bg:#e5edf9;--cB:#1d7a52;--cB-bg:#e2f3ea;--cC:#9a5a0b;--cC-bg:#fbefdc;--cD:#8a2f5e;--cD-bg:#f7e6ef}
html{scroll-behavior:smooth;scroll-padding-top:24px}
body{margin:0;background:var(--ivory);font-family:'Segoe UI',Arial,sans-serif;color:var(--ink);font-size:18px;line-height:1.65}
*{box-sizing:border-box}
a{color:var(--indigo);text-underline-offset:4px}
button,input,select{font:inherit}
button,select,summary{cursor:pointer}
button,select{min-height:44px;max-width:100%;border:1.5px solid var(--teal);border-radius:5px;padding:7px 14px;background:var(--paper);color:var(--teal)}
button:hover{background:#d1e8e0}
button[aria-pressed=true]{background:var(--teal);color:#fff}
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input[type=range]{width:100%;accent-color:var(--teal)}
button:focus-visible,a:focus-visible,select:focus-visible,input:focus-visible,summary:focus-visible{outline:3px solid #6b358d;outline-offset:3px}
p{margin:0 0 16px}
h1,h2,h3,h4{line-height:1.2;text-wrap:balance}
h3{font-size:1.22rem;margin:30px 0 12px;color:var(--indigo)}
h4{font-size:1.02rem;margin:18px 0 8px}
strong{font-weight:650}
sub,sup{line-height:0}
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.brand{color:var(--indigo);font-weight:750}
.masthead a{text-decoration:none}
.page-shell{max-width:1400px;display:grid;grid-template-columns:240px minmax(0,900px);gap:60px;margin:auto;padding:46px 40px}
.sidebar{align-self:start;position:sticky;top:24px;max-height:calc(100vh - 40px);overflow:auto}
.sidebar nav{display:grid;gap:3px}
.sidebar nav a{display:flex;gap:12px;font-size:.88rem;min-height:40px;align-items:center;text-decoration:none;padding:6px 8px;border-left:3px solid transparent;font-variant-numeric:tabular-nums}
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.sidebar .navpart{font-size:.7rem;letter-spacing:.12em;text-transform:uppercase;color:var(--muted);margin:14px 0 4px 8px;font-weight:700}
.skip{position:fixed;top:10px;left:10px;z-index:99;background:#fff;padding:12px;transform:translateY(-200%)}
.skip:focus{transform:none}
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.unit-header{padding:0 0 30px;border-bottom:2px solid var(--indigo);margin:0 0 26px}
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.scope-note{padding:18px 22px;border-left:3px solid #6d6599;background:#ece8f1;font-size:.93rem;margin:20px 0}
.scope-note p{margin:6px 0 0}
section{padding:40px 0 16px;border-bottom:1px solid var(--line);scroll-margin-top:20px}
h2.sec{color:var(--indigo);margin:0 0 24px;font-size:1.95rem}
h2.sec .oc{display:table;margin-top:10px;font-size:.72rem;font-weight:650;background:#e2e9fb;color:#303a70;border:1px solid #acb4cc;border-radius:4px;padding:3px 8px;letter-spacing:0}
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.crit.A{background:var(--cA-bg);color:var(--cA);border:1px solid var(--cA)}
.crit.B{background:var(--cB-bg);color:var(--cB);border:1px solid var(--cB)}
.crit.C{background:var(--cC-bg);color:var(--cC);border:1px solid var(--cC)}
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.box{border-radius:6px;padding:16px 20px;margin:20px 0;border-left:5px solid;font-size:.96rem}
.box>strong:first-child{display:block;margin-bottom:6px}
.box p:last-child,.box ul:last-child,.box ol:last-child{margin-bottom:0}
.def{background:#e8eefb;border-color:#3b5fb0}
.alert{background:#fdf1dc;border-color:#c77d0a}
.trap{background:#fbe9e7;border-color:#b23a2c}
.work{background:#e6f4ea;border-color:#2e7d4f}
.think{background:var(--teal-bg);border-color:var(--teal)}
.note{background:var(--lavender);border-color:var(--purple)}
.lens{background:#fff;border:1px solid var(--line);border-left:5px solid var(--indigo)}
.misc dl{margin:0}.misc dt{font-weight:650;margin-top:8px}.misc dd{margin:0 0 4px 0}
.tw{overflow-x:auto;margin:18px 0}
table{border-collapse:collapse;width:100%;font-size:.9rem;background:var(--paper)}
caption{caption-side:top;text-align:left;font-size:.82rem;color:var(--muted);padding:0 0 8px;font-weight:600}
th,td{border:1px solid var(--line);padding:7px 10px;text-align:left;vertical-align:top}
thead th{background:#ebe8f2;color:var(--indigo)}
.chem{font-family:'Cambria Math','Times New Roman',serif;font-size:1.08rem;background:#fff;border:1px dashed #9c8bbf;border-radius:4px;padding:10px 14px;margin:14px 0;overflow-x:auto;white-space:nowrap}
figure{margin:24px 0;background:#fff;border:1px solid var(--line);border-radius:6px;padding:14px}
figure svg{display:block;width:100%;height:auto;max-width:760px;margin:auto}
figcaption{font-size:.84rem;color:var(--muted);margin-top:10px}
figcaption b{color:var(--ink)}
.model{background:var(--teal-bg);border:1px solid #9fc9bc;border-radius:8px;padding:18px;margin:26px 0}
.model>h4{margin:0 0 4px;color:var(--teal);font-size:1.05rem}
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.model .controls{display:flex;flex-wrap:wrap;gap:10px;align-items:center;margin:10px 0}
.model .out{background:#fff;border-radius:6px;padding:12px 14px;margin-top:10px;font-size:.95rem}
.model svg{display:block;width:100%;height:auto;max-width:720px;margin:auto;background:#fff;border-radius:6px}
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.model label{font-size:.9rem}
.grid2{display:grid;grid-template-columns:1fr 1fr;gap:14px}
.pp{background:#fff;border:1px solid #c9c3d9;border-radius:8px;padding:18px 20px;margin:22px 0}
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.pp .pphead .tag{background:#efeaf7;border-radius:4px;padding:2px 8px;color:var(--purple)}
.pp .part{margin:10px 0}
.pp .part b.pl{color:var(--indigo)}
details{margin:12px 0}
details summary{font-weight:650;color:var(--teal);min-height:40px;display:flex;align-items:center}
details .sol{background:#f4f9f6;border-left:4px solid #2e7d4f;padding:12px 16px;border-radius:4px;font-size:.94rem}
details .sol ul{margin:4px 0 8px}
.mk{display:inline-block;background:#2e7d4f;color:#fff;border-radius:3px;font-size:.7rem;padding:0 6px;margin-right:6px;font-weight:700}
.eo{background:#fff8ec;border:1px solid #e3c58f;border-radius:8px;padding:18px 22px;margin:26px 0}
.eo h3{margin-top:0;color:#8a5a00}
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.ko>div{background:#fff;border:1px solid var(--line);border-radius:6px;padding:12px 14px;font-size:.88rem}
.ko>div h4{margin:0 0 6px;color:var(--indigo);font-size:.92rem}
.ko ul{margin:0;padding-left:18px}
.mcq-q{background:#fff;border-radius:6px;padding:12px 14px;margin:10px 0}
.mcq-q .opts{display:flex;flex-wrap:wrap;gap:8px;margin-top:8px}
.mcq-q .fb{margin-top:8px;font-size:.9rem}
.ok{color:#1d6b3f;font-weight:650}.bad{color:#a12c1f;font-weight:650}
.pill{display:inline-block;border:1px solid var(--line);background:#fff;border-radius:14px;padding:2px 10px;font-size:.8rem;margin:2px}
.ptable{display:grid;grid-template-columns:repeat(18,minmax(0,1fr));gap:2px;font-size:.62rem}
.ptable button{min-height:34px;padding:2px 0;border-radius:3px;border:1px solid #b9bfcc;color:var(--ink);line-height:1.1;font-size:.7rem}
.ptable button span{display:block;font-size:.55rem;color:#555}
.ptable .gap{visibility:hidden}
.legend{display:flex;flex-wrap:wrap;gap:6px;margin-top:8px}
.swatch{display:inline-block;width:14px;height:14px;border-radius:3px;vertical-align:middle;margin-right:4px;border:1px solid #999}
.critcard{display:grid;grid-template-columns:repeat(auto-fit,minmax(200px,1fr));gap:12px;margin:18px 0}
.critcard>div{border-radius:8px;padding:14px;font-size:.9rem}
.critcard .A{background:var(--cA-bg);border-top:4px solid var(--cA)}
.critcard .B{background:var(--cB-bg);border-top:4px solid var(--cB)}
.critcard .C{background:var(--cC-bg);border-top:4px solid var(--cC)}
.critcard .D{background:var(--cD-bg);border-top:4px solid var(--cD)}
.critcard h4{margin:0 0 6px}
.foot{font-size:.8rem;color:var(--muted);padding:30px 0 60px}
@media (max-width:980px){.page-shell{grid-template-columns:1fr;padding:24px 16px;gap:10px}.sidebar{position:static;max-height:none;border-bottom:1px solid var(--line);padding-bottom:10px}.sidebar nav{grid-template-columns:1fr 1fr}}
@media (max-width:640px){body{font-size:17px}.sidebar nav{grid-template-columns:1fr}.grid2{grid-template-columns:1fr}h2.sec{font-size:1.6rem}.ptable{font-size:.5rem}.ptable button{min-height:28px;font-size:.55rem}.ptable button span{display:none}.chem{font-size:.95rem}}
@media print{.sidebar,.masthead,.skip{display:none}.page-shell{display:block;padding:0}details{display:block}details>*{display:block}.model{break-inside:avoid}}

h3.critsec{margin:34px 0 10px;padding-top:12px;border-top:1px solid var(--line);font-size:1.12rem;display:flex;align-items:center;gap:8px}
.pp .ctx{background:#faf8f2;border-left:3px solid var(--line);padding:8px 12px;margin:8px 0 12px;font-size:.93rem}
.pp .ctx p{margin:.4em 0}
.pp p.blank{margin:.25em 0;color:var(--muted)}
ul.ms{margin:.3em 0;padding-left:1.2em}ul.ms li{margin:.2em 0}
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.pp .why{font-size:.9rem;border-top:1px dashed var(--line);padding-top:6px}