/* liaison_chimique.css */
@import url('https://fonts.googleapis.com/css2?family=Kanit:wght@200;300;400;500;600;700&family=Courier+Prime:wght@400;700&display=swap');
:root{--bg:#040206;--deep:#070310;--surface:#0d0820;--accent:#a060ff;--accent-dim:rgba(160,96,255,0.1);--border:rgba(160,96,255,0.15);--bond1:#ff6060;--bond2:#60b0ff;--bond3:#60ffb0;--bond4:#ffc060;--text:#6050a0;--text-bright:#c0a0ff;--text-dim:#200840;--white:#f0ecff;}
*,*::before,*::after{box-sizing:border-box;margin:0;padding:0;}
body{font-family:'Kanit',sans-serif;background:var(--bg);color:var(--text);min-height:100vh;overflow-x:hidden;}
#bond-canvas{position:fixed;inset:0;z-index:0;pointer-events:none;}
.wrap{position:relative;z-index:2;max-width:1040px;margin:0 auto;padding:0 28px 90px;}
.hero{padding:68px 0 52px;display:grid;grid-template-columns:1fr 280px;gap:44px;align-items:center;border-bottom:1px solid var(--border);margin-bottom:52px;}
.hero-tag{font-size:0.58rem;letter-spacing:5px;text-transform:uppercase;color:var(--accent);opacity:0.55;margin-bottom:14px;font-weight:300;}
.hero h1{font-size:clamp(3.5rem,10vw,7rem);font-weight:700;line-height:0.88;color:var(--white);letter-spacing:-2px;}
.hero h1 em{display:block;font-size:0.22em;font-style:normal;font-weight:200;letter-spacing:5px;color:var(--text-dim);margin-top:12px;font-family:'Courier Prime',monospace;text-transform:uppercase;}
.hero-desc{font-size:0.95rem;line-height:1.87;color:var(--text);font-weight:300;margin-top:16px;}
.bond-viz-wrap{background:var(--deep);border:1px solid var(--border);border-radius:8px;padding:20px;text-align:center;}
#bond-viz{display:block;margin:0 auto;}
.stats{display:grid;grid-template-columns:repeat(auto-fit,minmax(148px,1fr));border:1px solid var(--border);overflow:hidden;margin-bottom:52px;}
.stat{padding:16px 12px;background:var(--deep);border-right:1px solid var(--border);transition:background 0.2s;}.stat:last-child{border-right:none;}.stat:hover{background:var(--accent-dim);}
.s-label{font-family:'Courier Prime',monospace;font-size:0.52rem;letter-spacing:2px;text-transform:uppercase;color:var(--accent);opacity:0.5;margin-bottom:6px;}
.s-value{font-size:1rem;font-weight:600;color:var(--white);line-height:1.1;}
.s-unit{font-size:0.6rem;color:var(--text-dim);}
.section{margin-bottom:50px;opacity:0;transform:translateY(16px);transition:opacity 0.65s,transform 0.65s;}.section.visible{opacity:1;transform:none;}
.sh{display:flex;align-items:baseline;gap:14px;margin-bottom:18px;padding-bottom:12px;border-bottom:1px solid var(--border);}
.sn{font-family:'Courier Prime',monospace;font-size:0.55rem;letter-spacing:3px;color:var(--accent);opacity:0.4;}
.section h2{font-size:1.4rem;font-weight:700;color:var(--white);letter-spacing:-0.5px;}
p{font-size:0.95rem;line-height:1.87;color:var(--text);font-weight:300;margin-bottom:14px;}
strong{color:var(--text-bright);font-weight:600;}
.bonds-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(210px,1fr));gap:10px;margin-top:16px;}
.bc{background:var(--deep);border:1px solid var(--border);border-left:3px solid;padding:18px;transition:background 0.2s;}.bc:hover{background:var(--accent-dim);}
.bc h3{font-size:0.85rem;font-weight:600;color:var(--white);margin-bottom:4px;}
.bc .be{font-family:'Courier Prime',monospace;font-size:0.7rem;color:var(--text-dim);margin-bottom:8px;font-weight:700;}
.bc p{font-size:0.78rem;margin:0;line-height:1.55;}
.vsepr-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(170px,1fr));gap:8px;margin-top:16px;}
.vg{background:var(--deep);border:1px solid var(--border);padding:14px;text-align:center;transition:background 0.2s;}.vg:hover{background:var(--accent-dim);}
.vg-shape{font-size:1.3rem;margin-bottom:4px;}
.vg-name{font-size:0.78rem;font-weight:700;color:var(--white);margin-bottom:2px;}
.vg-angle{font-family:'Courier Prime',monospace;font-size:0.65rem;color:var(--accent);opacity:0.7;margin-bottom:4px;}
.vg p{font-size:0.72rem;color:var(--text);margin:0;line-height:1.4;}
.footer-band{margin-top:70px;border-top:1px solid var(--border);padding-top:20px;display:flex;justify-content:space-between;flex-wrap:wrap;gap:8px;}
.footer-band span{font-family:'Courier Prime',monospace;font-size:0.5rem;letter-spacing:2px;color:var(--text-dim);text-transform:uppercase;}
@media(max-width:640px){.hero{grid-template-columns:1fr;} .bond-viz-wrap{display:none;}}