/* A contained, explorable view of the engineering behind the worked example. */
.backend-foundations{border:1px solid #a6b7d8;border-radius:3px 23px 3px 3px;background:#fff;box-shadow:0 4px 0 #d9e1f0;overflow:hidden;margin:0 0 24px;color:#182e50}
.foundation-heading{display:flex;justify-content:space-between;gap:14px;align-items:flex-start;background:linear-gradient(120deg,#17365c,#091c36);padding:18px 20px;color:#f2f6ff}
.foundation-heading .mini-label{font-size:9px;color:#acc9ff;letter-spacing:.1em}
.foundation-heading h4{font-size:21px;line-height:1.2;letter-spacing:-.025em;font-weight:550;margin:7px 0 0;color:#f3f7ff}
.foundation-heading>span{font-size:10px;color:#cadbff;white-space:nowrap;margin-top:3px}
.foundation-choices{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:7px;padding:15px 18px;background:#eef3fc;border-bottom:1px solid #d5dfef}
.foundation-choices button{display:flex;justify-content:space-between;align-items:center;gap:8px;min-height:40px;font-size:11px;font-weight:600;line-height:1.35;text-align:left;color:#24406d;background:#fff;border:1px solid #a6b9db;border-radius:3px 13px 3px 3px;box-shadow:0 2px 0 #d2dcef;padding:8px 10px;cursor:pointer;transition:background .15s,border-color .15s}
.foundation-choices button>span{display:grid;place-items:center;width:17px;height:17px;flex:0 0 17px;border:1px solid #b6c7e7;border-radius:50%;font-size:12px;color:#2543ec}
.foundation-choices button[aria-pressed=true]{background:linear-gradient(145deg,#3d5cf9,#2341dd);color:#fff;border-color:#2341dd;box-shadow:0 2px 0 #1931a7}
.foundation-choices button[aria-pressed=true]>span{background:white;border-color:white;transform:rotate(45deg)}
.foundation-choices button:hover{border-color:#2543ec;background:#e4ebff}.foundation-choices button[aria-pressed=true]:hover{background:#2444e1}
.foundation-choices button:focus-visible,.foundation-example button:focus-visible,.backend-walkthrough summary:focus-visible{outline:3px solid #2543ec;outline-offset:4px}
.foundation-detail{display:grid;grid-template-columns:1fr 1fr;gap:20px;padding:19px 20px 20px}
.foundation-explanation h5{font-size:18px;font-weight:600;letter-spacing:-.025em;line-height:1.2;margin:0 0 10px;color:#182e50}
.foundation-explanation p{font-size:12px;line-height:1.65;color:#465c7c;margin:0}
.foundation-explanation .foundation-delivery{margin-top:13px;padding-top:12px;border-top:1px solid #d4deef;color:#294575}
.foundation-delivery strong{color:#143879}
.foundation-example{display:flex;flex-direction:column;background:#eef3fc;border:1px solid #d0dcf0;border-radius:3px 13px 3px 3px;padding:14px}
.foundation-example>.mini-label{font-size:8px;letter-spacing:.08em;color:#456394}
.foundation-condition{display:block;font-size:10px;color:#455f86;margin:12px 0 0;line-height:1.4}
.foundation-condition select{display:block;margin-top:5px;min-height:36px;font-size:11px;padding:7px 24px 7px 9px;background:#fff;border:1px solid #aabedc;color:#183b6d;border-radius:3px 9px 3px 3px}
.foundation-example>p:first-of-type{font-size:12px;line-height:1.55;color:#213d65;margin:10px 0 13px}
.foundation-example button{display:flex;align-items:center;justify-content:space-between;gap:12px;font-size:11px;font-weight:600;line-height:1.4;min-height:41px;text-align:left;color:#fff;background:#2543e8;border:1px solid #2543e8;border-radius:3px 20px 20px 3px;padding:7px 7px 7px 12px;cursor:pointer}
.foundation-example button>span{display:grid;place-items:center;flex:0 0 23px;width:23px;height:23px;border-radius:50%;background:#fff;color:#2442dc;font-size:16px}
.foundation-example button:hover{background:#1936c7}
.foundation-example .foundation-result{margin:13px 0 0;font-size:11px;line-height:1.6;color:#566b8b;min-height:4.8em;border-left:2px solid #acbedf;padding-left:10px}
.foundation-example .foundation-result[data-complete=true]{color:#173e73;border-left-color:#2543ec;background:#e2ebff;padding-block:5px}
.foundation-model-note{display:block;font-size:9px;line-height:1.45;color:#566c8d;margin-top:12px}
.backend-walkthrough{border-top:1px solid #bbcae2;padding-top:6px;margin-top:7px}
.backend-walkthrough summary{display:flex;align-items:center;justify-content:space-between;gap:15px;cursor:pointer;list-style:none;padding:13px 0;font-size:13px;font-weight:600;line-height:1.5;color:#1f4184}
.backend-walkthrough summary::-webkit-details-marker{display:none}.backend-walkthrough summary:after{content:'＋';display:grid;place-items:center;width:25px;height:25px;flex:0 0 25px;border-radius:50%;border:1px solid #9db4e2;color:#2543ec;background:#fff}
.backend-walkthrough[open] summary:after{content:'−'}
.backend-walkthrough[open] summary{margin-bottom:8px}
.backend-example-instruction{font-size:13px;line-height:1.6;color:#405a81;margin:0 0 17px}
@media(max-width:1050px){.foundation-detail{gap:17px}.foundation-heading{padding-inline:17px}.foundation-heading>span{display:none}.foundation-choices{padding-inline:16px}.foundation-choices button{font-size:11px;padding-inline:8px}}
@media(max-width:700px){.foundation-heading{padding:17px 15px}.foundation-heading h4{font-size:22px;max-width:22ch}.foundation-heading .mini-label{font-size:9px}.foundation-choices{grid-template-columns:repeat(2,minmax(0,1fr));padding:13px 12px;gap:8px}.foundation-choices button{min-height:44px;font-size:11px;padding-inline:9px}.foundation-detail{grid-template-columns:1fr;gap:16px;padding:17px 15px}.foundation-explanation h5{font-size:21px}.foundation-explanation p{font-size:13px;line-height:1.65}.foundation-example>.mini-label{font-size:9px}.foundation-condition{font-size:11px}.foundation-condition select{font-size:16px;min-height:44px}.foundation-example>p:first-of-type{font-size:13px}.foundation-example button{font-size:12px;min-height:44px}.foundation-example .foundation-result{font-size:12px;min-height:0}.foundation-model-note{font-size:10px}.backend-walkthrough summary{font-size:13px;min-height:48px}}
@media(prefers-reduced-motion:reduce){.foundation-choices button{transition:none}}