/* Account and public-entry surfaces share the portal's existing tokens. */
.guest-view #sidebar,.guest-view #menu-toggle,.guest-view #account-link,.guest-view .site-footer{display:none}
.guest-view .workspace{margin-left:0}
.guest-view .workspace main{max-width:1180px;padding:40px 36px 64px}
.guest-view .topbar{padding:0 max(24px,calc((100vw - 1108px)/2));background:#fff}
.guest-view .topbar #breadcrumb{font-size:14px;color:var(--ink);font-weight:650}
.guest-view #sync-status{display:none}
.guest-view .toast{left:50%}
#guest-account-links{display:flex;align-items:center;gap:20px}
#guest-account-links:empty,#guest-account-links[hidden]{display:none}
#guest-account-links>a{font-size:13px;font-weight:650;text-decoration:none}
#guest-account-links .button{min-height:40px;padding:10px 15px}
.welcome-wordmark{display:inline-block;text-decoration:none;color:var(--teal);font-size:23px;font-weight:750;letter-spacing:-.8px;margin-bottom:25px}
.welcome-hero{display:grid;grid-template-columns:minmax(0,1.35fr) minmax(300px,1fr);gap:66px;align-items:center;padding:20px 0 44px}
.welcome-intro h1{font:normal 51px/1.13 Georgia,serif;letter-spacing:-1.5px;margin:0 0 24px}
.welcome-intro>p{font-size:16px;max-width:52ch;color:var(--muted)}
.welcome-actions{display:flex;gap:18px;align-items:center;flex-wrap:wrap;margin:28px 0 17px}
.welcome-intro .welcome-signin{font-size:13px;margin:0}
.welcome-example{background:#fff;border:1px solid #c5dadd;border-radius:15px;padding:28px 29px;box-shadow:7px 7px 0 #e6eef1;transform:rotate(1deg)}
.welcome-example-heading{border-bottom:1px solid var(--line);padding-bottom:18px;margin-bottom:23px}
.welcome-example-heading>span{display:block;font-size:12px;color:var(--muted);margin-bottom:7px}
.welcome-example-heading>strong{display:block;font-size:20px;line-height:1.45;font-weight:650}
.welcome-variable{display:flex;align-items:center;justify-content:center;gap:20px;color:var(--teal);font-size:23px;margin:18px 0 12px}
.welcome-variable-name{font-family:Consolas,monospace;font-size:19px;border-bottom:2px solid var(--teal);padding:5px 11px}
.welcome-variable-value{display:grid;place-items:center;border:1px solid #bed7da;border-radius:8px;background:var(--sky);height:48px;min-width:48px;font-weight:700}
.welcome-example p{font-size:13px;color:var(--muted);margin:0 0 16px;line-height:1.65}
.welcome-code{background:var(--paper);border-radius:6px;padding:11px 15px;font-size:14px}
.welcome-code code{background:none;padding:0;white-space:normal}
.welcome-variable-after .welcome-variable-value{background:var(--teal);color:white;border-color:var(--teal)}
.welcome-example>a{display:inline-block;font-size:13px;font-weight:600;line-height:1.5;margin-top:2px}
.welcome-library{display:flex;justify-content:space-between;gap:18px;flex-wrap:wrap;padding:22px 0;border-top:1px solid var(--line);border-bottom:1px solid var(--line);font-size:13px;color:var(--muted)}
.welcome-library strong{color:var(--ink);font-weight:700;margin-right:5px}
.welcome-method{display:grid;grid-template-columns:1fr 1.5fr;gap:66px;padding:58px 0;border-bottom:1px solid var(--line)}
.welcome-method h2,.welcome-section-intro h2,.welcome-start h2{font-size:27px;line-height:1.3;letter-spacing:-.6px}
.welcome-method>div p,.welcome-section-intro p,.welcome-start p{font-size:14px;color:var(--muted);max-width:64ch}
.welcome-method-list{counter-reset:method;list-style:none;margin:0;padding:0}
.welcome-method-list li{position:relative;padding:0 0 19px 42px;counter-increment:method;margin:0}
.welcome-method-list li:before{content:counter(method);position:absolute;top:0;left:0;color:var(--teal);border:1px solid #bfd8db;background:var(--sky);width:26px;height:26px;display:grid;place-items:center;border-radius:50%;font-size:12px;font-weight:650}
.welcome-method-list strong{font-size:16px}
.welcome-method-list p{font-size:14px;color:var(--muted);margin:5px 0 0;line-height:1.7}
.welcome-method-list li:last-child{padding-bottom:0}
.welcome-path{display:grid;grid-template-columns:1fr 1.5fr;gap:66px;padding:54px 0;border-bottom:1px solid var(--line)}
.welcome-stages{list-style:none;padding:0;margin:0}
.welcome-stages li{display:flex;gap:20px;margin:0 0 23px}
.welcome-stages li:last-child{margin-bottom:0}
.welcome-stages li>span{font:normal 25px/1.5 Georgia,serif;color:#6d8389;flex:0 0 20px}
.welcome-stages h3{font-size:16px;margin-bottom:4px}
.welcome-stages p{font-size:13px;color:var(--muted);margin:0;line-height:1.7;max-width:65ch}
.welcome-samples{padding:48px 0}
.welcome-sample-list{margin-top:26px;border-top:1px solid var(--line)}
.welcome-sample-list a{display:grid;grid-template-columns:120px 1.1fr 1fr;gap:20px;padding:20px 0;border-bottom:1px solid var(--line);text-decoration:none;align-items:center}
.welcome-sample-list a:hover strong{text-decoration:underline;text-underline-offset:4px}
.welcome-sample-list span{font-size:12px;color:var(--teal);font-weight:650}
.welcome-sample-list strong{font-size:15px;color:var(--ink);line-height:1.6}
.welcome-sample-list small{font-size:13px;line-height:1.6}
.welcome-start{display:flex;align-items:center;justify-content:space-between;gap:32px;padding:28px 30px;background:var(--sky);border:1px solid #cce2e4;border-radius:12px}
.welcome-start h2{font-size:24px}
.welcome-start p{margin:0}
.welcome-start>.button{flex-shrink:0}
.account-auth-layout{display:grid;grid-template-columns:minmax(0,1fr) minmax(0,1fr);gap:74px;align-items:start;max-width:950px;margin:24px auto}
.account-auth-intro{padding-top:17px}
.account-auth-intro h1{font:normal 43px/1.18 Georgia,serif;letter-spacing:-1px}
.account-auth-intro>p{font-size:15px;color:var(--muted);max-width:45ch}
.account-auth-note{border-left:3px solid #b9d6d9;padding-left:19px;margin:36px 0 23px}
.account-auth-note h2{font-size:17px;letter-spacing:0}
.account-auth-note p{font-size:13px;color:var(--muted);margin:0}
.account-back{font-size:13px}
.account-form-panel{background:white;border:1px solid var(--line);border-radius:14px;padding:29px 31px}
.account-messages:empty{display:none}
.account-message{padding:14px 16px;border:1px solid var(--line);border-radius:8px;margin-bottom:20px;font-size:14px;line-height:1.7;overflow-wrap:anywhere}
.account-error{color:#8f2b36;background:#fff1f0;border-color:#e9bdc0}
.account-notice{color:#245d44;background:#eaf6f0;border-color:#bfddcf}
.account-message:focus{outline:3px solid #198a9a;outline-offset:4px}
.account-field{min-width:0;margin-bottom:20px}
.account-field>label{display:block;font-size:13px;font-weight:650;color:var(--ink);margin-bottom:9px;line-height:1.5}
.account-field>input,.account-field>select,.account-field>textarea,.account-password>input{display:block;width:100%;min-width:0;border:1px solid #c9d5df;border-radius:7px;padding:11px 12px;background:white;color:var(--ink);min-height:46px;font-size:16px;line-height:1.5}
.account-field>textarea{resize:vertical}
.account-field>input::placeholder,.account-field>textarea::placeholder{color:#647587;font-size:14px}
.account-password{display:flex;align-items:stretch;gap:8px}
.account-password>input{flex:1}
.password-toggle{flex:0 0 auto;min-width:56px;border:1px solid var(--line);border-radius:7px;background:var(--paper);color:var(--teal);padding:0 10px;font-size:12px;font-weight:650}
.password-toggle:hover{background:var(--sky)}
.account-field .account-field-hint,.account-field-hint{font-size:12px;line-height:1.6;color:var(--muted);margin:8px 0 0}
.account-submit{width:100%;margin-top:4px}
.account-form-link{text-align:center;font-size:13px;margin:19px 0 0}
.account-form-footer{border-top:1px solid var(--line);margin-top:26px;padding-top:19px}
.account-form-footer>p{font-size:13px;margin-bottom:0;line-height:1.7}
.account-form-footer>.account-field-hint{font-size:12px;margin-top:15px}
.account-recovery{max-width:660px;margin:12px auto;background:white;border:1px solid var(--line);border-radius:14px;padding:35px 39px}
.account-recovery h1{font-size:32px}
.account-recovery>p{font-size:15px;color:var(--muted)}
.recovery-key-panel{padding:20px;background:var(--paper);border:1px solid var(--line);border-radius:9px;margin:25px 0 20px}
.recovery-key-panel>.small-label{display:block;line-height:1.6}
#recovery-secret{display:block;white-space:pre-wrap;overflow-wrap:anywhere;word-break:break-word;padding:0;background:none;font-size:18px;line-height:1.8;user-select:all;color:var(--ink);margin-bottom:17px}
.recovery-key-panel .button{font-size:12px}
.recovery-guidance h2{font-size:18px;margin-top:26px}
.recovery-guidance p{font-size:13px;color:var(--muted)}
.account-checkbox{display:flex;align-items:flex-start;gap:11px;font-size:13px;line-height:1.7;margin:22px 0;cursor:pointer}
.account-checkbox>input{accent-color:var(--teal);width:18px;height:18px;flex:0 0 18px;margin:3px 0 0}
.account-checkbox>span{min-width:0}
.account-page{max-width:960px}
.account-overview{display:grid;grid-template-columns:minmax(0,1.2fr) minmax(0,1fr);gap:26px;padding:25px 0 30px;border-top:1px solid var(--line);border-bottom:1px solid var(--line)}
.account-identity h2{font-size:23px;margin-bottom:5px;overflow-wrap:anywhere}
.account-email{overflow-wrap:anywhere;color:var(--teal);font-size:14px!important;margin-bottom:12px}
.account-identity>p,.account-sync>p{font-size:13px;color:var(--muted)}
.account-overview-actions,.account-inline-actions{display:flex;gap:10px;flex-wrap:wrap}
.account-sync{border-left:1px solid var(--line);padding-left:26px}
.account-sync h2{font-size:17px}
.account-sync .button{font-size:12px;justify-content:flex-start}
.account-plan{background:white;border:1px solid var(--line);border-radius:12px;padding:27px 30px;margin:28px 0}
.account-section-heading h2{font-size:22px}
.account-section-heading>p{font-size:14px;color:var(--muted);margin-bottom:25px}
.account-field-row{display:grid;grid-template-columns:1fr 1.5fr;gap:18px}
.account-settings>h2{font-size:21px;margin:30px 0 18px}
.account-setting{border-top:1px solid var(--line)}
.account-setting:last-child{border-bottom:1px solid var(--line)}
.account-setting>summary{padding:19px 0;font-size:15px;font-weight:650;line-height:1.6;cursor:pointer;color:var(--ink)}
.account-setting[open]>summary{color:var(--teal)}
.account-setting-body{max-width:620px;padding:4px 0 24px 18px}
.account-setting-body>p{font-size:14px;color:var(--muted);max-width:70ch}
.account-setting-body h3{font-size:17px;margin-top:24px}
.account-setting-body form{margin-top:22px;max-width:470px}
.account-setting-danger>summary{color:var(--red)}
.account-signout{display:flex;align-items:center;justify-content:space-between;gap:20px;margin-top:30px;font-size:13px;color:var(--muted)}
.account-auth-status{font-size:13px;line-height:1.7;color:var(--muted);overflow-wrap:anywhere;margin-top:14px}
.account-auth-status:empty{display:none}
.account-conflicts{margin-top:22px;overflow-wrap:anywhere}
@media(max-width:900px){.welcome-hero{gap:35px;grid-template-columns:1.15fr 1fr}.welcome-intro h1{font-size:42px}.welcome-example{padding:23px}.welcome-method,.welcome-path{gap:35px}.welcome-sample-list a{grid-template-columns:95px 1.2fr 1fr;gap:15px}.account-auth-layout{gap:35px}.account-auth-intro h1{font-size:37px}.account-form-panel{padding:26px 24px}}
@media(max-width:700px){.guest-view .workspace main{padding:26px 20px 44px}.guest-view .topbar{padding:0 20px;height:70px}.guest-view .topbar #breadcrumb{font-size:13px;max-width:35%;line-height:1.4}.guest-view .top-actions{gap:0}#guest-account-links{gap:14px}#guest-account-links>a{font-size:12px}#guest-account-links .button{padding:9px 11px}.welcome-hero{grid-template-columns:1fr;gap:32px;padding:5px 0 31px}.welcome-intro h1{font-size:42px;max-width:15ch}.welcome-wordmark{font-size:21px;margin-bottom:20px}.welcome-intro>p{font-size:15px}.welcome-example{transform:none;box-shadow:4px 4px 0 #e6eef1;max-width:440px;width:100%;justify-self:center;padding:22px}.welcome-example-heading>strong{font-size:19px}.welcome-library{display:grid;grid-template-columns:1fr 1fr;gap:16px 12px;font-size:12px}.welcome-method,.welcome-path{grid-template-columns:1fr;gap:19px;padding:34px 0}.welcome-method h2,.welcome-section-intro h2{font-size:24px}.welcome-method h2 br{display:none}.welcome-method-list li{padding-left:39px}.welcome-path{gap:12px}.welcome-stages li{gap:15px;margin-bottom:20px}.welcome-samples{padding:34px 0}.welcome-sample-list{margin-top:20px}.welcome-sample-list a{grid-template-columns:1fr;gap:4px;padding:17px 0}.welcome-start{display:block;padding:23px}.welcome-start h2{font-size:23px}.welcome-start>.button{margin-top:22px}.account-auth-layout{grid-template-columns:1fr;gap:21px;max-width:490px;margin:0 auto}.account-auth-intro{padding:0}.account-auth-intro h1{font-size:34px;margin-bottom:15px}.account-auth-intro>p{font-size:14px;margin-bottom:12px}.account-auth-note{margin:18px 0 14px;padding-left:14px}.account-auth-note h2{font-size:15px}.account-auth-note p{font-size:12px}.account-back{font-size:12px}.account-form-panel{padding:24px 21px}.account-recovery{padding:25px 21px;margin:0}.account-recovery h1{font-size:29px}#recovery-secret{font-size:16px}.recovery-key-panel{padding:16px}.account-overview{grid-template-columns:1fr;gap:25px;padding:20px 0 25px}.account-sync{border-left:0;border-top:1px solid var(--line);padding:22px 0 0}.account-plan{padding:23px 19px}.account-field-row{grid-template-columns:1fr;gap:0}.account-setting-body{padding-left:0}.account-setting-body form{max-width:none}.account-overview-actions>.button{flex:1}.account-page .page-intro h1{font-size:29px}}
@media(max-width:380px){.guest-view .workspace main{padding-left:16px;padding-right:16px}.guest-view .topbar{padding:0 16px}#guest-account-links{gap:10px}.welcome-intro h1{font-size:37px}.account-form-panel{padding:21px 17px}.account-password{gap:6px}.password-toggle{min-width:49px;padding:0 8px}}

/* Curiosity-led landing: a quiet introduction beside an engineering story board. */
.welcome-hero.engineering-hero{grid-template-columns:minmax(0,1fr) minmax(0,1.25fr);gap:48px;align-items:center;padding:10px 0 40px}
.engineering-hero .welcome-wordmark{margin-bottom:24px}
.engineering-hero .welcome-intro h1{font-size:52px;line-height:1.1;letter-spacing:-1.8px;max-width:13ch}
.engineering-hero .welcome-intro>p{max-width:41ch;font-size:16px;line-height:1.8}
.welcome-invitation{display:flex;align-items:center;gap:9px;margin:20px 0 0;color:var(--teal);font-size:12px;font-weight:650}
.welcome-invitation::before{content:'';display:block;width:18px;height:2px;background:currentColor}
.engineering-spotlight{min-width:0;border:1px solid #29434a;border-radius:18px;background:#112b32;color:#f7fbfb;box-shadow:0 16px 36px #17363c16;overflow:hidden}
.spotlight-topline{display:flex;gap:12px;justify-content:space-between;align-items:center;padding:19px 24px;border-bottom:1px solid #365057;font-size:11px;color:#b3ced2;letter-spacing:.1px}
.spotlight-topline strong{display:flex;align-items:center;gap:8px;color:#d9ebed;font-weight:600}
.spotlight-signal{width:6px;height:6px;display:inline-block;background:#83cbc8;border-radius:50%}
.story-slide{padding:26px 28px 22px}
.story-slide[hidden]{display:none}
.story-company{display:flex;align-items:center;gap:9px;font-size:13px;font-weight:700;color:#d7eeee;margin-bottom:17px}
.story-company-mark{width:27px;height:27px;display:grid;place-items:center;border:1px solid #6c9b9f;border-radius:7px;font-size:12px;color:var(--story-accent,#b7e1df)}
.story-slide h2{font:normal 31px/1.23 Georgia,serif;letter-spacing:-.4px;color:#fff;margin-bottom:16px;min-height:3.7em}
.story-answer{font-size:14px;line-height:1.75;color:#c4dadd;min-height:5.3em;margin-bottom:17px}
.story-diagram{margin:0 0 20px;padding:17px 0 0;border-top:1px solid #365057}
.story-flow{display:flex;align-items:stretch;list-style:none;padding:0;margin:0;gap:20px}
.story-flow li{position:relative;flex:1;min-width:0;margin:0;padding:12px 5px;border:1px solid #49676d;border-radius:7px;background:#1b3a42;text-align:center;font-size:11px;line-height:1.5;font-weight:600;color:#f0f8f8}
.story-flow li+li::before{content:'→';position:absolute;right:calc(100% + 5px);top:50%;transform:translateY(-50%);font-size:14px;color:#89b5bb;font-weight:400}
.story-flow[data-flow="replication"] li+li::before{content:'↔'}
.story-diagram figcaption{margin-top:9px;color:#a2c0c5;font-size:10px;line-height:1.6}
.story-concepts{display:flex;flex-wrap:wrap;gap:6px;margin:0 0 21px;padding:0;list-style:none}
.story-concepts li{font-size:10px;line-height:1.5;padding:4px 8px;border:1px solid #45636a;border-radius:5px;margin:0;color:#cde0e3}
.story-links{display:flex;gap:15px;align-items:center;flex-wrap:wrap}
.story-links .button{background:#e0f4f2;color:#123c42;font-size:12px;padding:11px 14px;min-height:44px}
.story-links .button:hover{background:#fff}
.story-links .story-source{font-size:11px;color:#bbdadd;line-height:1.5}
.spotlight-bottom{padding:13px 24px;border-top:1px solid #365057;background:#0d242a;display:flex;align-items:center;justify-content:space-between;gap:12px}
.story-play{background:none;color:#d0e4e6;padding:10px 0;min-height:44px;text-align:left;font-size:11px}
.story-paging{display:flex;align-items:center;gap:9px;color:#a7c8cd;font-size:11px}
.story-arrow{width:36px;height:44px;border:1px solid #45636a;border-radius:7px;background:transparent;color:#e0eeee;font-size:20px;line-height:1}
.story-arrow:hover,.story-arrow:focus-visible{background:#24454d}
.story-selector{display:flex;gap:8px;flex-wrap:wrap;padding:0;margin:14px 0 0;list-style:none}
.story-selector li{margin:0;display:contents}
.story-selector button{border:1px solid #ccdadc;color:#466169;background:#fff;min-height:44px;padding:10px 12px;border-radius:7px;font-size:11px;font-weight:600;line-height:1.3}
.story-selector button[aria-current="true"]{background:var(--sky);border-color:var(--teal);color:var(--teal);box-shadow:inset 0 -2px 0 var(--teal)}
.engineering-story-group{min-width:0}
.engineering-story-group>.story-note{font-size:11px;line-height:1.6;color:var(--muted);margin:12px 0 0}
.welcome-bridge{display:grid;grid-template-columns:1fr 1.3fr;gap:48px;padding:35px 0;border-bottom:1px solid var(--line);align-items:start}
.welcome-bridge h2{font-size:24px;line-height:1.3;margin-bottom:10px}
.welcome-bridge p{font-size:14px;color:var(--muted);margin:0;max-width:53ch}
.welcome-bridge-steps{display:flex;list-style:none;padding:0;margin:6px 0;gap:16px}
.welcome-bridge-steps li{flex:1;min-width:0;border-top:2px solid #bad4d7;padding-top:13px;margin:0}
.welcome-bridge-steps strong{font-size:13px;display:block;line-height:1.5;margin-bottom:7px;color:var(--ink)}
.welcome-bridge-steps span{font-size:12px;line-height:1.6;color:var(--muted);display:block}
@media(min-width:1100px){.guest-view .workspace main:has(.engineering-hero){max-width:1280px}.engineering-hero .welcome-intro h1{font-size:58px}}
@media(max-width:1000px){.welcome-hero.engineering-hero{gap:28px}.engineering-hero .welcome-intro h1{font-size:43px}.story-slide{padding:22px}.story-slide h2{font-size:28px}.story-selector{gap:6px}.story-selector button{padding:8px 10px}.welcome-bridge{gap:30px}.welcome-bridge-steps{gap:10px}}
@media(max-width:760px){.welcome-hero.engineering-hero{grid-template-columns:1fr;gap:30px;padding:0 0 30px}.engineering-hero .welcome-intro h1{font-size:46px;max-width:17ch}.engineering-hero .welcome-intro>p{max-width:54ch;font-size:15px}.engineering-story-group{max-width:600px;width:100%;justify-self:center}.story-slide h2{min-height:2.5em;font-size:31px}.story-answer{min-height:0}.welcome-bridge{grid-template-columns:1fr;gap:19px;padding:28px 0}.welcome-bridge-steps{gap:17px}.spotlight-topline{padding:16px 22px}.welcome-actions{margin-top:22px}}
@media(max-width:420px){.engineering-hero .welcome-intro h1{font-size:40px}.story-slide{padding:21px 19px}.story-slide h2{font-size:28px}.story-answer{font-size:13px}.spotlight-topline,.spotlight-bottom{padding-left:19px;padding-right:19px}.story-flow{gap:15px}.story-flow li+li::before{right:calc(100% + 2px)}.story-flow li{font-size:10px}.story-selector button{font-size:10px;padding:9px 10px}.welcome-bridge-steps{gap:11px}.welcome-bridge-steps strong{font-size:12px}.welcome-bridge-steps span{font-size:11px}}
/* Guests see three clear destinations; lesson access begins after sign-in. */
#guest-account-links>a{min-height:44px;display:inline-flex;align-items:center}
@media(max-width:700px){.guest-view .topbar{padding:9px 16px;min-height:70px;height:auto;flex-wrap:nowrap}.guest-view .topbar #breadcrumb{max-width:none;font-size:12px;flex:none}.guest-view .top-actions{margin-left:auto}#guest-account-links{gap:12px}#guest-account-links>a{font-size:12px}#guest-account-links .button{padding:9px 10px;min-height:44px}}
@media(max-width:380px){.guest-view .topbar #breadcrumb{font-size:11px}.guest-view .topbar{padding-left:12px;padding-right:12px;gap:8px}#guest-account-links{gap:8px}#guest-account-links>a{font-size:11px}#guest-account-links .button{padding:9px 8px}}