/* Relief métallique inspiré du site de terminale, dans les trois couleurs de seconde. */
.matiere{--metal-top:#31d9db;--metal-mid:#087e92;--metal-base:#03485b;--metal-bottom:#032f43;--metal-edge:#69edf0;--badge-top:#eed8ff;--badge-mid:#a76cde;--badge-base:#54217e;--badge-edge:#e3baff}
.mouvement{--metal-top:#63bdff;--metal-mid:#2064c3;--metal-base:#14386e;--metal-bottom:#0b2149;--metal-edge:#a6dcff;--badge-top:#c8fffc;--badge-mid:#31c6cb;--badge-base:#086575;--badge-edge:#b9fffa}
.ondes{--metal-top:#cc94ff;--metal-mid:#8b45c5;--metal-base:#4c2475;--metal-bottom:#2d174b;--metal-edge:#e4bcff;--badge-top:#c8fffc;--badge-mid:#31c6cb;--badge-base:#086575;--badge-edge:#b9fffa}
.library-heading{margin-bottom:30px;align-items:center}.metal-title{width:290px;max-width:100%;margin:0 0 17px;line-height:0}.metal-title svg{display:block;width:100%;height:auto;overflow:visible;filter:drop-shadow(0 3px 2px #1d214427)}
.chapter-group>.group-heading,.chapter>summary{background:linear-gradient(160deg,#ffffff34 0%,#ffffff08 17%,transparent 33%,#ffffff15 44%,transparent 55%,#000b2029 100%),linear-gradient(174deg,var(--metal-top) 0%,var(--metal-mid) 13%,var(--metal-base) 48%,var(--metal-bottom) 100%);box-shadow:inset 0 2px 1px #ffffffb0,inset 0 -2px 2px #001025a6;color:#f6fdff;border-color:var(--metal-base);isolation:isolate}
.chapter-group>.group-heading{min-height:111px;padding:23px 25px;border-left:5px solid var(--metal-edge);border-radius:17px;gap:20px;box-shadow:inset 0 2px 1px #ffffffb0,inset 0 -2px 2px #001025a6,0 4px 0 #17364b6b,0 10px 18px #18375626}
.chapter-group{margin-bottom:24px}.chapter-group[open]>.group-heading{margin-bottom:20px}.chapter-group>.group-heading h3{font-size:23px;font-weight:800;line-height:1.3;text-shadow:0 2px 2px #00162f99;letter-spacing:-.35px}.chapter-group>.group-heading .eyebrow{font-size:10px;letter-spacing:.19em;color:var(--metal-edge);text-shadow:0 1px 1px #00162f}.chapter-group>.group-heading .total{color:#e3f5ff;font-weight:600}
.chapter-group>.group-heading .group-icon,.chapter-number{position:relative;flex-shrink:0;overflow:hidden;border:1px solid var(--badge-edge);background:linear-gradient(155deg,var(--badge-top),var(--badge-mid) 21%,var(--badge-base) 80%);color:#fff;box-shadow:inset 0 2px 1px #ffffffdd,inset 0 -2px 1px #001b4277,0 3px 0 #00132e80,0 5px 8px #00152555;text-shadow:0 2px 1px #06293a99}
.chapter-group>.group-heading .group-icon{width:58px;height:58px;border-radius:16px}.group-icon svg{width:35px;height:35px;filter:drop-shadow(0 2px 1px #15324d88)}
.chapter-group>.group-heading .group-icon::after,.chapter-number::after{content:'';position:absolute;inset:3px 4px auto;height:40%;border-radius:12px 12px 50% 50%;background:linear-gradient(#ffffff4d,#ffffff00);pointer-events:none}
.chapter{border:1px solid var(--metal-base);border-left:4px solid var(--metal-edge);border-radius:15px;margin:0 0 14px;box-shadow:0 3px 0 #15334b60,0 7px 13px #1837561c}.chapter:hover,.chapter[open]{border-color:var(--metal-edge);box-shadow:0 3px 0 #15334b60,0 8px 16px #18375626}.chapter>summary{min-height:100px;padding:20px 23px;gap:20px;border-left:0}.chapter>summary:hover,.chapter-group>.group-heading:hover{filter:brightness(1.07)}.chapter-label h4{color:#f6fdff;font-size:19px;font-weight:800;line-height:1.35;letter-spacing:-.2px;text-shadow:0 2px 2px #00162f99}.chapter-label p{color:#d4ecf8;font-size:12px;font-weight:500;margin-top:7px}.chapter-number{min-width:58px;width:58px;height:58px;font-size:21px;font-weight:800;border-radius:15px;letter-spacing:-.5px}.chapter-body{padding-left:102px}
.chapter .chevron,.group-chevron{display:grid;place-items:center;position:relative;width:29px;height:29px;flex:0 0 29px;border:1px solid var(--metal-edge);border-radius:50%;background:linear-gradient(150deg,var(--metal-top),var(--metal-mid) 50%,var(--metal-base));box-shadow:inset 0 1px 1px #ffffffa6,0 2px 2px #00162d99;transform:none;margin:0 0 0 10px}.chapter .chevron::after,.group-chevron::after{content:'';width:7px;height:7px;border-right:2px solid white;border-bottom:2px solid white;transform:translateY(-2px) rotate(45deg);transition:transform .2s}.chapter[open] .chevron,.chapter-group[open]>.group-heading .group-chevron{transform:none;margin-bottom:0}.chapter[open] .chevron::after,.chapter-group[open]>.group-heading .group-chevron::after{transform:translateY(2px) rotate(225deg)}
.theme-card{border-bottom:3px solid var(--soft);box-shadow:inset 0 2px 1px white,0 4px 0 #55778526,0 9px 18px #18375617}.theme-card>svg{padding:8px;box-sizing:content-box;border:1px solid var(--metal-edge);border-radius:15px;color:white;background:linear-gradient(150deg,var(--metal-top),var(--metal-mid) 35%,var(--metal-base));box-shadow:inset 0 2px 1px #ffffffce,inset 0 -2px 1px #001b424d,0 3px 5px #14364733;filter:drop-shadow(0 1px 1px #15324d44)}
/* Les chapitres sont plus clairs que les thèmes ; leurs pastilles gardent leur relief. */
.matiere{--chapter-top:#e5ffff;--chapter-mid:#a1e3e6;--chapter-base:#7bced7;--chapter-bottom:#60b7c5;--chapter-ink:#073746}
.mouvement{--chapter-top:#e6f4ff;--chapter-mid:#b5d7ff;--chapter-base:#9fc4f1;--chapter-bottom:#83abdd;--chapter-ink:#15305a}
.ondes{--chapter-top:#f6eaff;--chapter-mid:#ddc3f5;--chapter-base:#cda8e9;--chapter-bottom:#b58bd8;--chapter-ink:#36204e}
.chapter,.chapter:hover,.chapter[open]{border-color:var(--soft);border-left-color:var(--theme);box-shadow:0 3px 0 #43607945,0 7px 13px #18375617}
.chapter>summary{background:linear-gradient(160deg,#ffffff5c 0%,#ffffff0d 20%,transparent 33%,#ffffff38 44%,transparent 57%,#1639580a 100%),linear-gradient(174deg,var(--chapter-top) 0%,var(--chapter-mid) 16%,var(--chapter-base) 65%,var(--chapter-bottom) 100%);color:var(--chapter-ink);box-shadow:inset 0 2px 1px #ffffffed,inset 0 -2px 2px #2b557c44}
.chapter>summary:hover{filter:brightness(1.035)}
.chapter-label h4{color:var(--chapter-ink);text-shadow:0 1px 0 #ffffff99}
.chapter-label p{color:var(--chapter-ink);text-shadow:0 1px 0 #ffffff4d}
@media(max-width:1100px){.theme-card{gap:12px}.theme-card>svg{width:32px;height:32px;padding:7px}.theme-card strong{font-size:15px}}
@media(max-width:700px){.library-heading{margin-bottom:22px;flex-wrap:wrap}.metal-title{width:215px;margin:1px 0 15px}.library-heading>div{min-width:0;flex:1 1 100%}.library-heading p:not(.eyebrow){max-width:none}.chapter-count{font-size:11px}.chapter-group>.group-heading{min-height:111px;padding:18px 12px;gap:12px;border-radius:14px}.chapter-group>.group-heading h3{font-size:18px;letter-spacing:-.25px}.chapter-group>.group-heading .group-icon{width:43px;height:47px;border-radius:12px}.group-icon svg{width:28px;height:28px}.chapter-group>.group-heading .eyebrow{font-size:9px}.chapter-group{margin-bottom:21px}.chapter>summary{padding:18px 12px;gap:12px;min-height:94px}.chapter-number{width:45px;min-width:45px;height:48px;border-radius:12px;font-size:17px}.chapter-label h4{font-size:15px;line-height:1.4}.chapter-label p{font-size:10px;line-height:1.5;margin-top:6px}.chapter .chevron,.group-chevron{width:24px;height:24px;flex-basis:24px;margin-left:0}.chapter-body{padding:19px}.theme-card>svg{width:32px;height:32px;padding:7px}.theme-card strong{font-size:15px}}