/* PCBCalc AI — reference-inspired minimal chat design; other project pages are unchanged. */
:root{--paper:#fff;--side:#f5f5f4;--ink:#1f3138;--muted:#7d8b90;--border:#e4e7e7;--accent:#1c292b;--subtle:#f6f7f6}
*{box-sizing:border-box}html{height:100%}body{margin:0;color:var(--ink);font:400 14px/1.5 "Figtree",Arial,sans-serif;background:var(--paper)}button,textarea{font:inherit}button{cursor:pointer}a{color:inherit;text-decoration:none}.frame{min-height:100dvh}.shell{display:grid;grid-template-columns:258px minmax(0,1fr);min-height:100dvh}
.site-sidebar{min-width:0;min-height:100dvh;display:flex;flex-direction:column;background:var(--side);padding:24px 17px 22px;border-right:1px solid #e6e8e7;gap:0}
.brand-row{display:flex;align-items:center;justify-content:space-between;min-height:42px}.brand{display:flex;align-items:center;gap:11px;font-size:20px;font-weight:500;letter-spacing:-.8px;white-space:nowrap;color:#21352c}.brandmark{display:grid;grid-template-columns:repeat(2,9px);grid-template-rows:repeat(2,9px);gap:3px;transform:rotate(-7deg);margin-left:4px}.brandmark b{background:#34483b;border-radius:2px}.brandmark b:nth-child(2){opacity:.5}.brandmark b:nth-child(3){opacity:.67}.side-nav{display:grid;gap:4px;margin-top:42px}.nav,.new-chat{display:flex;align-items:center;gap:13px;min-height:46px;padding:9px 10px;border-radius:9px;font-size:14px;font-weight:400;color:#42535a;transition:background .14s}.nav:hover,.new-chat:hover,.session-item:hover{background:#e9ecea}.nav.active{background:#e2e7e1;color:#1e2d29;font-weight:500}.icon{width:20px;height:20px;flex:none;display:inline-block}.nav-robot{width:27px;height:32px;object-fit:contain;image-rendering:pixelated;margin:-5px -4px -5px -3px;animation:mascot-idle 3.5s ease-in-out infinite}
.sidebar-rule{height:1px;background:#e2e5e3;margin:22px 4px 14px}.new-chat{width:100%;border:0;text-align:left;background:transparent}.new-chat .icon{width:21px;height:21px;stroke-width:1.8}.history-heading{margin:35px 10px 14px;letter-spacing:1.1px;font-size:10px;color:#88969a;font-weight:500}.session-item{display:flex;align-items:center;gap:12px;margin:0 0 0 0;padding:11px 10px;border-radius:8px;color:#44555b;font-size:12px;overflow:hidden}.session-item .icon{width:15px;height:15px}.session-item span{white-space:nowrap;text-overflow:ellipsis;overflow:hidden}.sidebar-foot{margin-top:auto;padding:22px 10px 0;color:#99a4a6;font-size:11px;line-height:1.6}
.assistant-main{min-width:0;min-height:100dvh;background:var(--paper);display:flex;flex-direction:column;position:relative}.top{height:70px;min-height:70px;display:flex;align-items:center;justify-content:space-between;padding:0 32px;border-bottom:0;gap:18px}.top-title{font-weight:400;font-size:14px;color:#34474d}.top-right{display:flex;gap:10px;align-items:center}.pill{background:#fff;border:1px solid var(--border);border-radius:11px;display:flex;align-items:center;gap:9px;padding:9px 13px;color:#3b5057;font-size:12px;min-height:38px}.pill.alt{background:#fafafa}.pill .chevron{width:14px;height:14px}.pill.theme{padding:8px;width:39px;justify-content:center}.pill .sun-icon,.pill .moon-icon{width:19px;height:19px}.pill .moon-icon{display:none}.language-short{display:none}
.assistant-canvas{display:flex;flex-direction:column;flex:1;min-height:0;position:relative}.conversation-scroll{width:100%;min-height:0;overflow-y:auto;scrollbar-width:thin}.chat-welcome{width:min(870px,calc(100% - 64px));margin:clamp(66px,11vh,114px) auto 0;text-align:center}.robot-stage{display:flex;align-items:center;justify-content:center;height:72px}.welcome-robot{height:69px;width:auto;image-rendering:pixelated;animation:mascot-idle 3s ease-in-out infinite;filter:drop-shadow(0 2px 2px #00000012)}.welcome-heading{font-weight:400;letter-spacing:-1.3px;font-size:clamp(25px,2.5vw,37px);line-height:1.25;margin-top:15px;color:#263b43}
.assistant-canvas:not(.has-messages) .conversation-scroll{flex:0 0 auto;overflow:visible}.assistant-canvas:not(.has-messages) .composer-wrap{margin:45px auto 0;width:min(870px,calc(100% - 64px));padding-bottom:48px}
.composer-wrap{width:min(870px,calc(100% - 64px));margin:0 auto 0;padding-bottom:27px}.message-composer{border:1.4px solid #d8dedf;background:#fff;border-radius:24px;padding:17px 20px 13px;box-shadow:0 2px 5px #182b3008,0 1px 1px #182b3007;transition:border .15s,box-shadow .15s}.message-composer:focus-within{border-color:#9babb0;box-shadow:0 0 0 3px #62777713}.message-composer textarea{display:block;border:0;resize:none;outline:none;background:transparent;width:100%;height:61px;min-height:61px;max-height:170px;color:#1c3035;font-weight:400;font-size:16px;line-height:1.65;padding:2px 6px;box-shadow:none}.message-composer textarea::placeholder{color:#8c9ba2;opacity:1}.composer-bottom{display:flex;align-items:center;justify-content:space-between;padding:4px 1px 0;gap:10px}.composer-note{font-size:11px;color:#91a0a3}.composer-actions{display:flex;align-items:center;gap:10px}.send-message{width:38px;height:38px;border-radius:50%;background:var(--accent);color:white;border:0;display:flex;align-items:center;justify-content:center;transition:transform .12s,background .14s}.send-message:hover{background:#374c53}.send-message:active{transform:scale(.96)}.send-message .icon{height:21px;width:21px;stroke-width:2}.composer-new{display:none;width:37px;height:37px;align-items:center;justify-content:center;border-radius:50%;background:#f2f4f4;color:#2f454b;border:1px solid #e0e6e6}
.suggestion-grid{display:flex;gap:8px;justify-content:center;flex-wrap:wrap;margin-top:18px}.suggestion{display:flex;align-items:center;gap:9px;border:1px solid #e9edec;border-radius:18px;padding:7px 12px;color:#637379;background:#fafbfa;font-size:11px}.suggestion:hover{background:#f0f4f2;color:#324747}.suggestion .icon{width:13px;height:13px;stroke-width:1.8}.privacy-note{text-align:center;color:#a2abad;font-size:10px;line-height:1.6;margin-top:15px}
.assistant-canvas.has-messages .conversation-scroll{flex:1;overflow:auto}.assistant-canvas.has-messages .chat-welcome{display:none}.assistant-canvas.has-messages .composer-wrap{margin-top:auto}.assistant-canvas.has-messages .suggestion-grid{display:none}.messages{width:min(850px,calc(100% - 64px));margin:30px auto 24px;display:flex;flex-direction:column;gap:20px}.chat-message{padding:13px 17px;font-size:14px;line-height:1.7;white-space:pre-wrap;overflow-wrap:anywhere;max-width:85%;border-radius:16px}.chat-message.user{align-self:flex-end;background:#f1f3f2;color:#273c42}.chat-message.system{align-self:flex-start;color:#63777d;background:transparent;padding-left:0;font-size:13px;max-width:100%}
.mobile-brand,.mobile-nav-close,.mobile-menu-button,.mobile-overlay{display:none}.sr-only{position:absolute;width:1px;height:1px;padding:0;margin:-1px;overflow:hidden;clip:rect(0,0,0,0);white-space:nowrap;border:0}#demoNotice{position:fixed;bottom:12px;right:12px;background:#fff;border:1px solid var(--border);padding:13px 16px;border-radius:8px;box-shadow:0 4px 18px #0001;color:#223b41;z-index:8}#demoNotice[hidden],.mobile-overlay[hidden]{display:none}.new-chat:focus-visible,.nav:focus-visible,.pill:focus-visible,.suggestion:focus-visible,.send-message:focus-visible,.composer-new:focus-visible{outline:2px solid #6e9184;outline-offset:3px}
body.dark{--paper:#151a19;--side:#1c2421;--ink:#e9eeeb;--muted:#a8b9b5;--border:#36413c;--accent:#dce5e0;background:var(--paper);color:var(--ink)}body.dark .site-sidebar{border-color:#303d37}body.dark .brand{color:#f0f5f1}body.dark .brandmark b{background:#cbd8cc}body.dark .nav,body.dark .new-chat,body.dark .session-item{color:#b8c5bd}body.dark .nav.active{background:#35443b;color:#f4f6f3}body.dark .nav:hover,body.dark .new-chat:hover{background:#2b362f}body.dark .sidebar-rule{background:#35423a}body.dark .top-title{color:#c9d5cd}body.dark .pill,body.dark .pill.alt{color:#dde5df;background:#202923;border-color:#374339}body.dark .pill .sun-icon{display:none}body.dark .pill .moon-icon{display:inline-block}body.dark .welcome-heading{color:#e4ebe5}body.dark .message-composer{background:#1e2923;border-color:#46574c;box-shadow:none}body.dark .message-composer textarea{color:#eff5ef}body.dark .message-composer textarea::placeholder{color:#a5b4aa}body.dark .composer-note,body.dark .privacy-note{color:#98a9a0}body.dark .send-message{background:#dce5df;color:#253a30}body.dark .suggestion{background:#222d26;color:#bdcbc0;border-color:#394940}body.dark .chat-message.user{background:#35463a;color:#e9f1e9}body.dark .chat-message.system{color:#b0c5b3}body.dark .composer-new{background:#2c3a30;border-color:#47574b;color:#dee9de}body.dark #demoNotice{background:#26342a;color:#d4e1d5}
@keyframes mascot-idle{0%,100%{transform:translateY(0) rotate(-.8deg)}50%{transform:translateY(-4px) rotate(.8deg)}}@media(prefers-reduced-motion:reduce){.welcome-robot,.nav-robot{animation:none!important}}
@media(max-width:920px){.shell{grid-template-columns:220px minmax(0,1fr)}.site-sidebar{padding-left:12px;padding-right:12px}.chat-welcome{margin-top:80px}}
@media(max-width:700px){.shell{display:block}.site-sidebar{display:none}.assistant-main{min-height:100dvh}.top{height:64px;min-height:64px;border-bottom:1px solid var(--border);padding:0 16px}.top-title{display:none}.mobile-brand{display:flex;align-items:center;gap:9px;font-weight:500;font-size:16px;letter-spacing:-.6px}.mini-mark{transform:rotate(-7deg) scale(.75);margin-right:-2px}.mobile-menu-button{display:flex}.mobile-nav-close{display:inline-flex;align-items:center;justify-content:center;background:transparent;border:0;width:34px;height:34px}.chat-welcome{margin-top:clamp(50px,13vh,100px);width:calc(100% - 36px)}.welcome-robot{height:58px}.welcome-heading{font-size:27px;letter-spacing:-.9px;margin-top:15px}.assistant-canvas:not(.has-messages) .composer-wrap{margin-top:37px}.composer-wrap,.assistant-canvas:not(.has-messages) .composer-wrap{width:calc(100% - 32px);padding-bottom:23px}.message-composer{border-radius:20px;padding:14px 13px 11px}.message-composer textarea{font-size:15px;height:70px;min-height:70px}.composer-new{display:flex}.composer-note{font-size:10px;max-width:70%}.suggestion-grid{margin-top:15px}.suggestion{font-size:10px}.privacy-note{font-size:9px}.messages{width:calc(100% - 32px)}.assistant-canvas.has-messages .composer-wrap{padding-bottom:12px}.assistant-canvas.has-messages .conversation-scroll{min-height:0}.mobile-overlay{position:fixed;inset:0;background:#101e1d85;z-index:10;border:0}.mobile-overlay:not([hidden]){display:block}body.nav-open .site-sidebar{position:fixed;top:0;bottom:0;left:0;z-index:11;display:flex;min-height:100dvh;width:min(290px,86vw);box-shadow:15px 0 40px #0002;overflow:auto}body.nav-open .mobile-overlay{display:block}}
@media(max-width:385px){.top{padding:0 10px}.top-right{gap:6px}.pill{padding:7px 9px}.language-short{display:inline}.pill.alt #languageLabel{display:none}.pill.theme{width:36px}.welcome-heading{font-size:24px}.composer-note{font-size:9px}.suggestion{max-width:100%}}

/* v7 — Requested chat-composer refinements only */
.message-composer{padding-top:15px;padding-bottom:12px}
.message-composer textarea{height:51px;min-height:51px}
.composer-actions{margin-left:auto}
@media(max-width:700px){
 .message-composer{padding-top:13px;padding-bottom:10px}
 .message-composer textarea{height:60px;min-height:60px}
}