#design-history{margin:48px 0;scroll-margin-top:110px}
.history-workspace{display:grid;grid-template-columns:minmax(130px,1fr) minmax(260px,1.8fr) minmax(160px,1fr);gap:32px;align-items:start;padding:28px 0}
#history-features,#history-stages{display:flex;flex-direction:column;gap:18px}
.history-workspace .eyebrow{margin:0 0 22px;font-size:.7rem}
.history-workspace button{font-family:inherit;border:1px solid transparent;background:#191d17;color:var(--muted);padding:14px 16px;border-radius:6px;text-align:left;font-size:.875rem;line-height:1.4;cursor:pointer;min-height:46px}
.history-workspace button:hover{border-color:#879d5c;color:var(--ink)}
.history-workspace button[aria-pressed=true]{color:var(--green);background:#2c351e;border-color:#9bbf55}
.history-workspace button:focus-visible,.history-timeline:focus-visible{outline:2px solid var(--green);outline-offset:5px}
.history-visual{min-width:0;text-align:center;padding:0 30px 0 4px}
#history-stack{position:relative;width:min(100%,245px);aspect-ratio:122/264;margin:0 auto;isolation:isolate;perspective:1000px}
.history-phone{position:absolute;inset:0;padding:5px;border:1px solid #62675e;border-radius:28px;background:#090b09;box-shadow:0 18px 36px #0006;overflow:hidden;transform-origin:center;transform:translate(calc(var(--direction)*var(--depth)*22px),calc(var(--depth)*14px)) scale(calc(1 - var(--depth)*.07));z-index:calc(10 - var(--depth));opacity:calc(1 - var(--depth)*.19);transition:transform .35s ease,opacity .35s ease;pointer-events:none}
.history-phone[data-offset="0"]{pointer-events:auto;opacity:1}
.history-phone-screen{height:100%;overflow-y:auto;overscroll-behavior:contain;border-radius:22px;background:#51458c;scrollbar-width:none}
.history-phone-screen::-webkit-scrollbar{display:none}
.history-phone-screen .history-screen-media{display:block;width:100%;height:auto;max-width:100%;margin:0;border-radius:0}.history-phone-screen video{min-height:100%;object-fit:contain}
#history-count{font-size:.75rem;line-height:1.5;color:var(--muted);margin:30px 0 0}
.history-timeline{min-width:0;max-height:590px;overflow-y:auto;scrollbar-width:thin;scrollbar-color:#53613c transparent;padding:0 4px 12px 20px}
#history-stages{position:relative;gap:26px;padding-left:24px}
#history-stages:before{content:"";position:absolute;left:0;top:23px;bottom:23px;width:1px;background:#60664f}
#history-stages button{position:relative;width:100%}
#history-stages button:before{content:"";position:absolute;width:11px;height:11px;left:-31px;top:17px;border:1px solid #858b79;border-radius:50%;background:#818675}
#history-stages button[aria-pressed=true]:before{background:var(--green);border-color:var(--green);box-shadow:0 0 13px #b6e66655}
.history-controls{display:flex;gap:8px;margin:22px 0 0 24px}
.history-controls button{text-align:center;font-size:1.1rem;padding:8px 16px}
.history-controls button:disabled{opacity:.3;cursor:default}
.history-sr{position:absolute;width:1px;height:1px;overflow:hidden;clip-path:inset(50%)}
@media(max-width:1250px){.history-workspace{gap:16px;grid-template-columns:125px minmax(200px,1.5fr) minmax(140px,1fr)}.history-visual{padding-right:24px}.history-workspace button{padding:12px 9px;font-size:.8rem}.history-timeline{padding-left:4px}}
@media(max-width:700px){.history-workspace{grid-template-columns:minmax(0,1.3fr) minmax(120px,1fr);gap:24px 12px}.history-feature-panel{grid-column:1/-1}#history-features{flex-direction:row;gap:8px}#history-features button{flex:1}.history-feature-panel .eyebrow{margin-bottom:12px}.history-visual{padding-right:25px}#history-stack{max-width:225px}.history-phone{border-radius:23px}.history-phone-screen{border-radius:18px}.history-timeline{max-height:490px}#history-stages{gap:15px;padding-left:18px}#history-stages button:before{left:-25px}.history-controls{margin-left:18px}}
@media(prefers-reduced-motion:reduce){.history-phone{transition:none}}

/* Paired evidence: each explanation follows its own image. */
.evidence-columns{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:28px;align-items:start;margin:32px 0}
.evidence-columns section{min-width:0}
.evidence-columns figure{margin:0 0 20px}
.evidence-columns p{margin:0;font-size:1rem;line-height:1.65}
@media(max-width:900px){.evidence-columns{grid-template-columns:1fr;gap:36px}}