/* อ่านเพลิน: ธีมน้ำเงินเข้ม → ฟ้า (โลโก้ตัว a) */
:root{
  --paper:#F7F4EE; --sheet:#FFFDF9; --sand:#ECEFF6; --line:#E1E4EC; --line2:#C9CFDC;
  --ink:#15203D; --muted:#5B6479; --walnut:#0F1E4A; --leather:#13285E; --leather2:#2A4C9A;
  --brass:#FFD84D; --brass-dark:#1D6FE0; --brass-light:#FFE680; --wine:#1D6FE0; --wine-dark:#1550B0;
  --grad:linear-gradient(120deg,#0F1E4A 0%,#173A8C 55%,#1D6FE0 100%);
  --serif:'Prompt',sans-serif; --sans:'IBM Plex Sans Thai',sans-serif; --read:'Noto Serif Thai',serif;
}
*{box-sizing:border-box}
html{scroll-behavior:smooth}
body{margin:0;font-family:var(--sans);color:var(--ink);font-size:17px;line-height:1.65;overflow-x:hidden}
a{color:var(--wine)}a:hover{color:var(--wine-dark)}
button{font-family:inherit;cursor:pointer;color:inherit}
input,textarea,select{font-family:inherit;font-size:16px;color:var(--ink)}
img{max-width:100%;display:block}
:focus-visible{outline:3px solid var(--brass);outline-offset:2px}
.sr{position:absolute;width:1px;height:1px;overflow:hidden;clip:rect(0 0 0 0);white-space:nowrap}
.wrap{max-width:1200px;margin:0 auto;padding:0 20px}
.serif{font-family:var(--serif)}
.muted{color:var(--muted)}

/* พื้นผิว */
.paper{background-color:var(--paper)}
.wood{background-color:var(--walnut);background-image:var(--grad);color:#fff}
.leather{background-color:#0B1638;background-image:radial-gradient(120% 90% at 85% 10%,rgba(29,111,224,.55),transparent 60%),linear-gradient(160deg,#0B1638,#13285E);color:#fff}
.orn::after{content:"";display:block;margin-top:10px;width:44px;height:5px;border-radius:9px;background:linear-gradient(90deg,#1D6FE0 0 70%,#FFD84D 70%)}
.rule{display:flex;align-items:center;gap:8px}
.rule::before,.rule::after{content:"";flex:1;height:1px;background:rgba(255,255,255,.35)}
.rule span{width:8px;height:8px;border-radius:50%;background:var(--brass)}

/* ปุ่ม */
.btn{display:inline-flex;align-items:center;justify-content:center;gap:8px;min-height:48px;padding:0 22px;border-radius:999px;border:1px solid transparent;font-weight:700;font-size:16px;text-decoration:none;transition:transform .2s,filter .2s,background .2s}
.btn:hover{transform:translateY(-2px);filter:brightness(1.07)}
.btn:active{transform:scale(.96)}
.btn[disabled]{opacity:.5;cursor:not-allowed;transform:none;filter:none}
.btn-wine{background:linear-gradient(120deg,#1550B0,#1D6FE0);color:#fff}.btn-wine:hover{color:#fff}
.btn-brass{background:var(--brass);color:#0F1E4A}
.btn-dark{background:var(--walnut);color:var(--paper)}
.btn-green{background:var(--leather);color:var(--paper)}
.btn-line{background:transparent;border-color:var(--wine);color:var(--wine)}
.btn-ghost{background:transparent;border-color:var(--ink);color:var(--ink)}
.btn-ghost-light{background:rgba(255,255,255,.08);border-color:rgba(255,255,255,.55);color:#fff}.btn-ghost-light:hover{color:#fff}
.btn-sm{min-height:44px;padding:0 14px;font-size:14px;font-weight:600;white-space:nowrap}
.btn-block{width:100%}
.icon-btn{width:44px;height:44px;border-radius:999px;border:none;display:inline-flex;align-items:center;justify-content:center;background:var(--sand);font-size:20px}

/* แถบเมนู */
.topbar{position:sticky;top:0;z-index:20;box-shadow:0 6px 18px rgba(15,30,74,.25)}
.topbar .wrap{display:flex;flex-wrap:wrap;align-items:center;gap:12px;padding-top:10px;padding-bottom:10px}
.logo{display:flex;align-items:center;gap:10px;color:#fff;text-decoration:none;font-family:var(--serif);font-size:25px;font-weight:600;letter-spacing:.01em}
.logo:hover{color:#fff}
.logo svg{flex:none;border-radius:10px;box-shadow:0 3px 10px rgba(0,0,0,.18)}
.nav{display:flex;flex-wrap:wrap;gap:2px}
.nav a{padding:10px 12px;color:#fff;text-decoration:none;font-weight:500}
.nav a:hover{color:var(--brass-light)}
.top-actions{display:flex;gap:8px;margin-left:auto;align-items:center}
.search{width:100%;max-width:240px;min-height:44px;border:1px solid var(--line2);border-radius:999px;padding:0 16px;background:var(--sheet)}
.badge{display:inline-flex;min-width:24px;height:24px;border-radius:999px;background:var(--brass);color:#0F1E4A;align-items:center;justify-content:center;font-size:13px;font-weight:700;padding:0 6px}

/* ปก */
.cover{position:relative;width:100%;aspect-ratio:2/3;border:none;padding:22px 14px 14px 22px;text-align:left;border-radius:3px 10px 10px 3px;box-shadow:6px 8px 18px rgba(15,30,74,.22);display:flex;flex-direction:column;justify-content:space-between;overflow:hidden;background-size:cover;background-position:center}
.cover::before{content:"";position:absolute;left:0;top:0;bottom:0;width:8px;background:rgba(0,0,0,.2)}
.cover .c-cat{font-size:11px;letter-spacing:.03em;opacity:.85}
.cover .c-title{font-family:var(--serif);font-weight:700;font-size:19px;line-height:1.3}
.cover .c-author{font-size:12px}
.cover.has-img>span{display:none}
.lift{transition:transform .4s cubic-bezier(.2,.8,.2,1),box-shadow .4s}
.lift:hover{transform:translateY(-10px) rotate(-1.5deg);box-shadow:16px 22px 34px rgba(15,30,74,.3)}
.tilt{transform:perspective(900px) rotateY(-18deg) rotateX(4deg);transition:transform .7s cubic-bezier(.2,.8,.2,1);animation:float 6s ease-in-out infinite}
.tilt:hover{transform:perspective(900px) rotateY(0) rotateX(0) scale(1.03)}

/* การ์ดหนังสือ */
.grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(170px,1fr));gap:30px 22px}
.bcard{display:flex;flex-direction:column;gap:8px}
.bcard .cwrap{position:relative}
.heart{position:absolute;top:8px;right:8px;width:44px;height:44px;border-radius:999px;border:none;background:rgba(255,252,246,.92);display:flex;align-items:center;justify-content:center;z-index:1}
.heart svg{transition:transform .2s}
.heart.on svg{fill:#E0457B}
.tag-new{position:absolute;left:14px;bottom:-10px;background:var(--brass);color:#0F1E4A;font-size:12px;font-weight:700;padding:2px 12px;border-radius:999px;z-index:1}
.bcard .t{font-weight:600;line-height:1.4;font-size:16px;margin-top:12px}
.bcard .row{display:flex;justify-content:space-between;align-items:center;gap:8px}
.price{font-weight:700}

.chip{min-height:44px;padding:0 16px;border-radius:999px;font-size:15px;font-weight:600;border:1px solid var(--line2);background:#fff;color:var(--walnut)}
.chip[aria-pressed="true"],.chip[aria-selected="true"]{background:var(--walnut);border-color:var(--walnut);color:var(--paper)}
.catlabel{display:inline-block;font-size:11px;font-weight:700;border-radius:6px;padding:0 8px}
.cat-rom{background:#FCE3EC;color:#A3214F}.cat-fan{background:#ECE6FD;color:#4B2FB0}.cat-mys{background:#E1E7F5;color:#13285E}.cat-know{background:#DDF3EC;color:#0F6B53}
.cat-bl{background:#FDE7F7;color:#9B1F7E}.cat-hor{background:#E9E4E4;color:#3B1010}.cat-dra{background:#FFF1DC;color:#8A4B00}
.cat-biz{background:#FFF6CC;color:#6B5200}.cat-self{background:#E3F1FF;color:#0B4F94}.cat-health{background:#E2F6DF;color:#2C6A1F}.cat-edu{background:#FFE9E0;color:#A33A12}.cat-tech{background:#E6E9F2;color:#1E2B4F}

/* หน้าต่างซ้อน */
.overlay{position:fixed;inset:0;z-index:50;background:rgba(10,18,45,.6);display:flex;align-items:center;justify-content:center;padding:16px}
.overlay[hidden]{display:none}
.dialog{background:var(--sheet);border-radius:24px;width:100%;max-width:560px;max-height:92vh;overflow:auto;padding:28px;animation:up .45s cubic-bezier(.2,.8,.2,1) both}
.dialog.wide{max-width:820px}
.dialog-head{display:flex;justify-content:space-between;align-items:center;gap:12px;margin-bottom:8px}
.dialog-head h2{font-family:var(--serif);font-size:26px;margin:0}
.drawer{position:fixed;inset:0;z-index:50;background:rgba(10,18,45,.6);display:flex;justify-content:flex-end}
.drawer[hidden]{display:none}
.drawer>div{background:var(--sheet);width:100%;max-width:420px;height:100%;padding:24px;display:flex;flex-direction:column;gap:10px;overflow:auto}
.field{display:block;margin-bottom:14px}
.field span{display:block;font-weight:600;margin-bottom:4px}
.field input,.field textarea,.field select{width:100%;min-height:50px;border:1px solid var(--line2);border-radius:12px;padding:10px 14px;background:#fff}
.field textarea{min-height:120px;line-height:1.7}
.err{color:#9B1C1C;min-height:1.4em;font-size:15px;margin:6px 0 0}
.note{background:var(--paper);border-radius:16px;padding:16px;margin-bottom:16px}
.pay-opts{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:10px;margin:8px 0 18px}
.pay-opts button{min-height:72px;border-radius:16px;font-size:16px;font-weight:700;line-height:1.4;border:2px solid var(--line2);background:#fff}
.pay-opts button[aria-pressed="true"]{border-color:var(--wine);background:#E8F0FD}
.pay-opts small{display:block;font-weight:400;font-size:14px}

.toast{position:fixed;left:50%;bottom:28px;z-index:90;background:var(--ink);color:#fff;padding:14px 22px;border-radius:999px;box-shadow:0 12px 30px rgba(0,0,0,.3);max-width:calc(100% - 32px);animation:toast .45s cubic-bezier(.3,1.4,.5,1) both;transform:translateX(-50%)}
.pop{animation:pop .5s cubic-bezier(.3,1.6,.5,1)}
.up{animation:up .7s cubic-bezier(.2,.8,.2,1) both}
.spin{animation:wob .18s linear infinite}
.glow{animation:glow 5s ease-in-out infinite}
.marq{display:flex;gap:48px;width:max-content;animation:marq 32s linear infinite}
@keyframes up{from{opacity:0;transform:translateY(20px)}to{opacity:1;transform:none}}
@keyframes pop{0%{transform:scale(1)}40%{transform:scale(1.45)}100%{transform:scale(1)}}
@keyframes toast{from{opacity:0;transform:translate(-50%,30px) scale(.9)}to{opacity:1;transform:translate(-50%,0) scale(1)}}
@keyframes wob{0%{transform:rotate(-4deg) scale(.97)}50%{transform:rotate(4deg) scale(1.03)}100%{transform:rotate(-4deg) scale(.97)}}
@keyframes marq{from{transform:translateX(0)}to{transform:translateX(-50%)}}
@keyframes float{0%,100%{translate:0 0}50%{translate:0 -10px}}
@keyframes glow{0%,100%{opacity:.35;transform:scale(1)}50%{opacity:.6;transform:scale(1.08)}}
@media (prefers-reduced-motion:reduce){*{animation:none!important;transition:none!important}}

.loading{padding:40px 0;text-align:center;color:var(--muted)}
footer.site{padding:40px 20px;text-align:center;font-size:15px;color:#C9D6F2}
footer.site a{color:#fff}

.btn[hidden]{display:none}
.logo-a{display:inline-block;width:36px;height:36px}