.study-part-nav{display:flex;gap:5px;padding:6px;background:#f0f4f8;border-radius:18px;overflow-x:auto;flex-shrink:0;margin:8px 28px}.study-part-nav button{flex:1;white-space:nowrap;border-radius:13px;background:transparent;padding:12px 18px;color:#60758d;font-weight:700}.study-part-nav button[aria-pressed=true]{background:#fff;color:#00886c;box-shadow:0 2px 8px #17362812}.study-part-nav button:disabled{opacity:.4}.library-parts{margin:22px 0 30px;padding:8px;background:white;border:1px solid #dce5ed}.library-parts button[aria-pressed=true]{background:#00a57e;color:white}.study-actions{display:flex;justify-content:center;gap:10px;flex-wrap:wrap;padding:10px 0 0}.study-actions button{display:flex;gap:8px;align-items:center;background:#f3f6fa;border:1px solid #e0e7ef;padding:10px 16px;border-radius:22px;font-weight:600;font-size:13px}.study-actions .study-ai{background:white;box-shadow:0 3px 12px #17453612;color:#136e58}.ai-orb{display:inline-block;width:25px;height:25px;flex-shrink:0;border-radius:50%;background:radial-gradient(circle at 35% 30%,#fff 10%,#d2fff2 32%,#c4b4ff 60%,#eda4ec 85%)}
#study-helper{width:min(620px,calc(100% - 24px));max-height:90dvh;padding:24px;border:1px solid #e2e8f0;border-radius:26px;color:#17283c;background:white;box-shadow:0 25px 100px #132a3440;overflow:auto}#study-helper::backdrop{background:#17283c55;backdrop-filter:blur(3px)}#study-helper header{display:flex;align-items:center;justify-content:space-between}#study-helper header>div{display:flex;align-items:center;gap:12px}#study-helper h2{font-size:22px;margin:0}#helper-close{background:#f0f4f8;border-radius:50%;width:36px;height:36px;font-size:24px}#helper-lesson{color:#64748b;font-size:13px}.helper-options{display:flex;gap:12px;margin:18px 0}.helper-options label{flex:1;min-width:0;font-size:12px;font-weight:700}.helper-options select{display:block;width:100%;margin-top:6px}.helper-suggestions{display:grid;grid-template-columns:1fr 1fr;gap:8px}.helper-suggestions button{padding:12px;border:1px solid #dce5ed;border-radius:12px;background:#f8fafc;text-align:left;font-size:13px}.helper-suggestions button:hover{background:#eafaf3}.helper-privacy{line-height:1.6;font-size:11px;color:#64748b;margin:16px 0}#helper-answer{white-space:pre-wrap;line-height:1.8;font-size:15px;padding:18px;background:#effaf6;border-radius:14px;min-height:90px;max-height:32dvh;overflow:auto}#helper-form{margin-top:16px}#helper-message{width:100%;min-height:64px;border:1px solid #dce5ed;border-radius:12px;padding:12px;resize:vertical}#helper-form button{display:block;margin:10px 0 0 auto}.helper-message-label{display:block;font-size:12px;margin-bottom:5px}
@media(max-width:640px){.study-part-nav{margin:6px 12px;padding:4px;border-radius:12px}.study-part-nav button{padding:9px 12px;font-size:11px}.library-parts{margin:18px 0}.study-actions{gap:5px;padding-top:8px}.study-actions button{font-size:11px;padding:7px 10px;min-height:34px}.ai-orb{width:19px;height:19px}#study-helper{padding:18px;max-height:94dvh;border-radius:20px}.helper-options{gap:8px}.helper-options label:first-child{flex:1.5}.helper-suggestions button{font-size:12px;padding:10px}}

.instant-arabic{padding:22px;margin:0 0 24px;border:1px solid #b8e3d6;border-radius:16px;background:#effbf5;color:#184c3c}.instant-arabic>button{float:left;border-radius:50%;width:30px;height:30px;background:white;font-size:22px}.arabic-text{white-space:pre-wrap;font-size:18px;line-height:2;margin-top:16px}

.practice-theme-nav{display:flex;flex:1 1 100%;gap:8px;flex-wrap:wrap;width:100%;padding-top:8px}.practice-theme-nav button{flex:1 1 130px;min-height:44px;white-space:normal}.practice-theme-nav button:disabled{opacity:.45;cursor:default}

/* Part names keep their own width in scrollable desktop menus. On phones every
   option gets a complete cell, including disabled parts and Arabic labels. */
.study-part-nav{min-width:0;max-width:100%;overflow-y:hidden}
.study-part-nav>button,#library-parts.study-part-nav>button{flex:0 0 auto;min-width:max-content;overflow-wrap:normal}
.study-part-nav>button:disabled,#library-parts.study-part-nav>button:disabled{opacity:1;color:#64748b;background:#f8fafc}
@media(max-width:640px){
 #library-parts.study-part-nav.library-parts,.study-part-nav.exam-library-parts{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:6px;overflow:visible;padding:6px}
 #library-parts.study-part-nav.library-parts>button,.study-part-nav.exam-library-parts>button{width:100%;min-width:0;min-height:48px;padding:10px 8px;font-size:13px;white-space:normal;overflow-wrap:break-word;line-height:1.45;text-align:center}
}