/* Syntropy Textbooks — shared styles */

:root{
  --ink:#0F1B2D;
  --slate:#1E3A5F;
  --amber:#E9A03C;
  --amber-deep:#C17E1F;
  --paper:#FAF6EF;
  --paper-2:#F2EADB;
  --gray:#5B6572;
  --line:rgba(15,27,45,.12);
  --display:'Fraunces',Georgia,'Times New Roman',serif;
  --body:'Inter',system-ui,-apple-system,sans-serif;
  --wrap:1120px;
}

*{box-sizing:border-box;}
html{scroll-behavior:smooth;}
body{
  margin:0;
  background:var(--paper);
  color:var(--ink);
  font-family:var(--body);
  font-size:17px;
  line-height:1.7;
  -webkit-font-smoothing:antialiased;
}

h1,h2,h3{font-family:var(--display);font-weight:600;line-height:1.1;margin:0 0 .5em;letter-spacing:-.01em;}
h1{font-size:clamp(2.4rem,6vw,4rem);}
h2{font-size:clamp(1.7rem,3.4vw,2.5rem);}
h3{font-size:1.3rem;}
p{margin:0 0 1.1em;}
a{color:inherit;}

.wrap{max-width:var(--wrap);margin:0 auto;padding:0 24px;}
.eyebrow{font-size:.78rem;letter-spacing:.16em;text-transform:uppercase;font-weight:600;color:var(--gray);margin:0 0 1rem;}
.lead{font-size:1.18rem;color:var(--slate);max-width:52ch;}
.muted{color:var(--gray);}

/* ---------- buttons ---------- */
.btn{display:inline-block;padding:13px 26px;border-radius:10px;font-weight:600;font-size:.98rem;
  text-decoration:none;transition:transform .15s ease,background .15s ease;cursor:pointer;border:none;}
.btn-primary{background:var(--amber);color:var(--ink);}
.btn-primary:hover{background:var(--amber-deep);color:var(--paper);transform:translateY(-1px);}
.btn-ghost{background:transparent;color:var(--ink);border:1.5px solid var(--ink);}
.btn-ghost:hover{background:var(--ink);color:var(--paper);}

/* ---------- header ---------- */
.site-head{position:sticky;top:0;z-index:20;background:rgba(250,246,239,.86);
  backdrop-filter:saturate(1.2) blur(8px);border-bottom:1px solid var(--line);}
.site-head .wrap{display:flex;align-items:center;justify-content:space-between;height:74px;}
.brand{display:flex;align-items:center;gap:12px;text-decoration:none;color:var(--ink);}
.brand .word{font-family:var(--display);font-size:1.5rem;font-weight:600;line-height:1;}
.brand .sub{font-size:.6rem;letter-spacing:.28em;font-weight:600;color:var(--gray);display:block;margin-top:3px;}
.nav{display:flex;gap:28px;align-items:center;}
.nav a{text-decoration:none;font-size:.95rem;font-weight:500;color:var(--slate);padding:4px 0;border-bottom:2px solid transparent;}
.nav a:hover{border-bottom-color:var(--amber);}
.nav a.active{color:var(--ink);border-bottom-color:var(--amber);}

/* ---------- hero ---------- */
.hero{padding:72px 0 84px;}
.hero-grid{display:grid;grid-template-columns:1.05fr .95fr;gap:56px;align-items:center;}
.hero h1{margin-bottom:.35em;}
.hero .accent{color:var(--amber-deep);}
.hero-cta{display:flex;gap:14px;flex-wrap:wrap;margin-top:1.8rem;}
.field-card{background:var(--paper-2);border:1px solid var(--line);border-radius:18px;
  padding:20px;overflow:hidden;}
.field-card svg{display:block;width:100%;height:auto;}

/* ---------- generic sections ---------- */
.section{padding:76px 0;}
.section.alt{background:var(--paper-2);border-top:1px solid var(--line);border-bottom:1px solid var(--line);}
.section-head{max-width:60ch;margin-bottom:2.6rem;}

/* ---------- definition ---------- */
.def{display:grid;grid-template-columns:1fr;gap:0;background:var(--ink);color:var(--paper);
  border-radius:20px;overflow:hidden;}
.def-inner{padding:clamp(32px,5vw,56px);}
.def .term{font-family:var(--display);font-size:clamp(2.6rem,7vw,4.4rem);font-weight:600;line-height:1;margin:0;}
.def .pos{font-style:italic;color:var(--amber);font-size:1.1rem;margin-left:.4rem;}
.def .pron{color:#9DB0C7;font-size:.95rem;margin:.6rem 0 1.6rem;letter-spacing:.02em;}
.def .body{font-size:1.15rem;line-height:1.75;max-width:60ch;color:#E9E3D7;}
.def .body b{color:var(--paper);font-weight:600;}
.def .roots{display:flex;gap:32px;flex-wrap:wrap;margin:1.8rem 0 0;padding-top:1.6rem;border-top:1px solid rgba(255,255,255,.14);}
.def .root .k{font-family:var(--display);font-size:1.4rem;color:var(--amber);}
.def .root .v{font-size:.9rem;color:#9DB0C7;}
.def .source{font-size:.8rem;color:#7D8CA3;margin:1.6rem 0 0;}

/* ---------- pillars ---------- */
.pillars{display:grid;grid-template-columns:repeat(3,1fr);gap:24px;}
.pillar{padding:28px;border:1px solid var(--line);border-radius:16px;background:var(--paper);}
.pillar .n{font-family:var(--display);font-size:1.05rem;color:var(--amber-deep);font-weight:600;margin-bottom:.5rem;}
.pillar h3{margin-bottom:.35em;}
.pillar p{margin:0;color:var(--gray);font-size:.98rem;}

/* ---------- textbooks ---------- */
.book-feature{display:grid;grid-template-columns:300px 1fr;gap:44px;align-items:start;
  background:var(--paper);border:1px solid var(--line);border-radius:20px;padding:40px;}
.book-cover{aspect-ratio:3/4;border-radius:12px;background:var(--ink);color:var(--paper);
  padding:30px 26px;display:flex;flex-direction:column;justify-content:space-between;position:relative;overflow:hidden;}
.book-cover .bc-top{font-size:.68rem;letter-spacing:.2em;text-transform:uppercase;color:#9DB0C7;}
.book-cover .bc-title{font-family:var(--display);font-size:1.7rem;line-height:1.1;font-weight:600;}
.book-cover .bc-rule{width:40px;height:3px;background:var(--amber);margin:14px 0;}
.book-cover .bc-foot{font-size:.72rem;color:#9DB0C7;letter-spacing:.04em;}
.badge{display:inline-block;background:var(--amber);color:var(--ink);font-weight:600;
  font-size:.78rem;letter-spacing:.06em;padding:6px 14px;border-radius:999px;margin-bottom:1rem;}
.diff-list{list-style:none;padding:0;margin:1.4rem 0 0;display:grid;gap:14px;}
.diff-list li{display:flex;gap:12px;align-items:flex-start;font-size:1rem;}
.diff-list .dot{flex:0 0 auto;width:9px;height:9px;border-radius:50%;background:var(--amber);margin-top:9px;}
.diff-list b{font-weight:600;}

.roadmap{display:grid;grid-template-columns:1fr 1fr;gap:24px;margin-top:28px;}
.rm-card{border:1.5px dashed var(--line);border-radius:16px;padding:32px;background:transparent;}
.rm-card .rm-tag{font-size:.75rem;letter-spacing:.16em;text-transform:uppercase;color:var(--gray);font-weight:600;}
.rm-card h3{margin:.6rem 0 .3rem;color:var(--slate);}
.rm-card p{margin:0;color:var(--gray);font-size:.95rem;}

/* ---------- contact ---------- */
.contact-grid{display:grid;grid-template-columns:.9fr 1.1fr;gap:56px;align-items:start;}
.form-field{margin-bottom:20px;}
.form-field label{display:block;font-size:.85rem;font-weight:600;letter-spacing:.02em;margin-bottom:7px;color:var(--slate);}
.form-field input,.form-field textarea,.form-field select{
  width:100%;padding:13px 15px;border:1px solid var(--line);border-radius:10px;background:var(--paper);
  font-family:var(--body);font-size:1rem;color:var(--ink);transition:border-color .15s ease,box-shadow .15s ease;}
.form-field input:focus,.form-field textarea:focus,.form-field select:focus{
  outline:none;border-color:var(--amber);box-shadow:0 0 0 3px rgba(233,160,60,.22);}
.form-field textarea{resize:vertical;min-height:150px;}
.hidden-field{position:absolute;left:-9999px;}

/* ---------- footer ---------- */
.site-foot{background:var(--ink);color:#B9C4D3;margin-top:0;}
.site-foot .wrap{padding-top:52px;padding-bottom:52px;display:flex;justify-content:space-between;
  align-items:flex-end;gap:32px;flex-wrap:wrap;}
.site-foot .word{font-family:var(--display);font-size:1.5rem;color:var(--paper);font-weight:600;}
.site-foot .sub{font-size:.62rem;letter-spacing:.28em;color:#7D8CA3;margin-top:4px;}
.site-foot .tag{font-size:.9rem;max-width:34ch;margin-top:12px;color:#9DB0C7;}
.site-foot .fnav{display:flex;gap:22px;font-size:.9rem;}
.site-foot .fnav a{color:#B9C4D3;text-decoration:none;}
.site-foot .fnav a:hover{color:var(--amber);}
.site-foot .legal{width:100%;border-top:1px solid rgba(255,255,255,.12);padding-top:20px;
  font-size:.8rem;color:#7D8CA3;}

/* ---------- responsive ---------- */
@media(max-width:820px){
  .hero-grid{grid-template-columns:1fr;gap:36px;}
  .hero{padding:48px 0 60px;}
  .pillars{grid-template-columns:1fr;}
  .book-feature{grid-template-columns:1fr;gap:28px;padding:28px;}
  .book-cover{max-width:240px;}
  .roadmap{grid-template-columns:1fr;}
  .contact-grid{grid-template-columns:1fr;gap:36px;}
  .nav{gap:18px;}
  .brand .sub{display:none;}
}
@media(max-width:520px){
  body{font-size:16px;}
  .section{padding:52px 0;}
  .nav a{font-size:.88rem;}
}

@media(prefers-reduced-motion:reduce){
  html{scroll-behavior:auto;}
  *{transition:none !important;}
}