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#00000020}dialog::backdrop{background:#00000066;backdrop-filter:blur(5px)}.dialog-close{position:absolute;top:15px;right:17px;width:29px;height:29px;display:flex;align-items:center;justify-content:center;border-radius:50%;background:#f5f5f7;color:#86868b;font-size:21px}.dialog-close:hover{background:#e8e8ed}dialog .eyebrow{font-size:12px;color:#86868b;margin-top:10px}dialog h2{font-size:30px;letter-spacing:-1px;line-height:1.35;margin:20px 0}dialog>p{font-size:16px;color:#6e6e73;line-height:1.8}.dialog-note{font-size:13px;line-height:1.8;color:#86868b;margin:25px 0}.dialog-back{display:block;background:none;color:#0066cc;font-size:13px;margin:24px auto 0;padding:5px}.wechat-contact{border-radius:16px;background:#f5f5f7;padding:20px;margin-top:25px}.wechat-contact>span{font-size:12px;color:#86868b}.wechat-contact>div{display:flex;align-items:center;justify-content:space-between;gap:15px;margin:15px 0}.wechat-contact code{font-family:var(--font);font-size:23px;font-weight:600;letter-spacing:-.4px;color:#1d1d1f;user-select:all}.wechat-contact button{white-space:nowrap;background:#0071e3;color:white;border-radius:20px;padding:8px 12px;font-size:11px}.wechat-contact small{font-size:12px;color:#86868b;line-height:1.7;display:block;min-height:20px}.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}
.phone-device{height:510px}.product-stage{height:590px}
@media(min-width:1500px){.hero{padding-top:70px}.hero h1{font-size:88px}.product-stage{margin-top:70px}}
@media(max-width:1100px){.wrap{padding-left:32px;padding-right:32px}.nav{height:64px}.nav nav{gap:24px}.hero h1{font-size:70px}.hero-lead{font-size:20px}.product-stage{height:530px;margin-top:50px}.desktop-device{left:32px;width:calc(100% - 145px);height:450px;top:25px;padding:9px;border-radius:25px}.device-screen{border-width:4px;border-radius:16px}.device-toolbar{height:34px;padding:0 14px;font-size:10px}.desktop-app{height:calc(100% - 34px)}.app-sidebar{width:117px;padding:22px 12px}.product-wordmark{gap:7px;margin-bottom:24px}.product-wordmark i{width:23px;height:24px;font-size:14px}.product-wordmark b{font-size:17px}.sidebar-item{font-size:10px;gap:7px;padding:10px 8px}.sidebar-item i{font-size:15px}.sidebar-bottom{font-size:10px;left:21px}.desktop-main{padding:24px 22px 18px}.desktop-greeting h3{font-size:23px}.desktop-greeting{margin-bottom:21px}.desktop-content{gap:15px;grid-template-columns:1.12fr 1fr}.desktop-task{gap:8px;padding:13px 0}.task-app-icon{width:30px;height:32px;font-size:21px;border-radius:8px}.desktop-task b{font-size:10px}.desktop-task p{font-size:8px}.desktop-task small{font-size:8px}.daily-heading h4{font-size:12px}.daily-heading>span{font-size:8px}.weekly-plan{padding:12px;margin-top:14px}.weekly-plan>b{font-size:10px}.week-dots{margin-top:12px}.knowledge-preview{padding:14px 12px}.knowledge-top{font-size:8px}.knowledge-top small{display:none}.preview-equation{font-size:14px;margin-top:18px}.concept-tags{font-size:7px;gap:5px}.concept-tags span{padding:6px}.phone-device{width:213px;height:490px;right:33px;bottom:0;padding:13px 11px 4px}.phone-app-head{margin-bottom:14px}.phone-overview{padding:13px}.phone-overview h3{font-size:22px}.phone-assignment{padding:12px}.phone-bottom{margin-top:14px}.home-indicator{margin:11px auto 0}.hero-specs{gap:48px;margin-top:38px}.hero-specs b{font-size:18px}.app-section{padding-left:40px;padding-right:40px}.app-grid{gap:45px}.app-story>p{font-size:18px}.app-detail p{font-size:16px}.app-story h3{font-size:34px}.practice-body{padding:26px}.practice h3{font-size:23px}.practice-actions{gap:17px}.practice-actions .button{font-size:13px;padding:12px 16px}.hint-button{font-size:13px}h2{font-size:46px}.section-intro{font-size:16px}.arts h2{font-size:64px}.arts-labels small{font-size:10px}.season{padding:23px;min-height:210px}.season p{font-size:13px}.service-table thead th{padding:15px 18px 30px}.service-table td{padding:21px 18px}.closing{margin-left:32px;margin-right:32px}.faq-section{gap:65px}}
@media(max-width:800px){.nav nav{gap:18px;font-size:11px}.hero{padding-top:50px}.hero-brand{font-size:21px}.hero h1{font-size:60px;letter-spacing:-2.5px}.hero-lead{font-size:19px}.product-stage{height:470px}.desktop-device{width:calc(100% - 120px);height:396px;padding:8px;top:18px;border-radius:23px;left:32px}.device-screen{border-width:4px}.device-toolbar{height:29px;padding:0 11px;font-size:8px}.window-controls{gap:4px}.window-controls i{width:5px;height:5px}.toolbar-profile{font-size:8px}.desktop-app{height:calc(100% - 29px)}.app-sidebar{width:95px;padding:18px 10px}.product-wordmark{gap:6px}.product-wordmark b{font-size:13px}.product-wordmark i{width:19px;height:20px;font-size:12px;border-radius:5px}.sidebar-item{font-size:8px;padding:8px 5px;gap:6px}.sidebar-item i{font-size:12px}.sidebar-bottom{font-size:8px;left:16px;bottom:20px}.sidebar-bottom small{font-size:7px}.desktop-main{padding:22px 17px 15px}.desktop-greeting h3{font-size:20px}.desktop-greeting p{font-size:9px}.demo-mark{display:none}.desktop-content{grid-template-columns:1fr}.daily-heading h4{font-size:11px}.desktop-task{padding:12px 0}.task-app-icon{width:32px;height:33px}.desktop-task b{font-size:11px}.desktop-task p{font-size:8px}.weekly-plan{margin-top:13px;padding:12px}.weekly-plan>b{font-size:10px}.weekly-plan>span{font-size:8px}.week-dots i{width:20px;height:20px;font-size:8px}.week-dots{margin-top:10px}.knowledge-preview{display:none}.phone-device{width:198px;height:463px;right:33px;padding:12px 10px 3px;border-radius:34px}.phone-top{margin-bottom:22px}.phone-top i{width:55px;height:15px}.phone-app-head{margin-bottom:12px}.phone-app-head b{font-size:18px}.phone-overview{padding:11px}.phone-overview h3{font-size:20px;margin-top:7px;margin-bottom:9px}.phone-overview>small{font-size:7px}.phone-overview>span{font-size:7px}.phone-assignment{padding:11px;margin-top:8px}.phone-assignment>span{margin-bottom:7px;font-size:7px}.phone-assignment>b{font-size:12px}.phone-assignment>small{font-size:7px;margin-top:6px}.phone-assignment a{font-size:8px;padding:7px;margin-top:9px}.phone-review{margin-top:8px;padding:9px}.phone-review b{font-size:9px}.phone-review small{font-size:7px}.phone-bottom{font-size:7px;margin-top:13px}.home-indicator{margin:10px auto 0;width:60px;height:3px}.hero-specs{gap:35px;font-size:11px}.hero-specs b{font-size:16px}.hero .product-caption{font-size:10px}.arts{padding-top:80px}.arts h2{font-size:56px}.arts-head>p{font-size:18px}.arts-labels{gap:7px}.arts-labels b{font-size:25px}.arts-labels small{font-size:9px}.method-section{padding:90px 0}.method-section h2{font-size:56px}.method-lead{font-size:19px}.learning-five{gap:12px;margin-top:50px}.learning-five b{font-size:27px}.learning-five span{font-size:11px}.section{padding-top:90px;padding-bottom:90px}h2{font-size:42px}.section-heading{display:block;margin-bottom:42px}.section-heading>.section-intro{margin-top:26px;font-size:17px}.section-heading>.text-link{margin-top:26px}.app-section{padding-left:32px;padding-right:32px}.app-grid{gap:32px;grid-template-columns:.95fr 1.05fr}.app-story h3{font-size:30px}.app-story>p{font-size:16px;margin-bottom:25px}.app-detail b{font-size:16px}.app-detail p{font-size:14px}.app-detail{margin:22px 0}.roadmap-note{font-size:11px}.practice-top{padding:18px;font-size:12px}.practice-top small{font-size:9px}.practice-body{padding:22px}.practice h3{font-size:21px}.question-category{font-size:10px}.answer{padding:12px;gap:10px;font-size:13px;border-radius:10px}.answer span{font-size:10px}.practice-actions{gap:12px}.practice-actions .button{font-size:11px;padding:11px 14px}.hint-button{font-size:11px}.practice .caption{font-size:9px}.feedback,.hint-box{font-size:12px}.seasons{grid-template-columns:1fr 1fr;gap:16px}.season{min-height:180px}.subject-tabs{gap:10px}.subject-art{font-size:33px}.subject-name{font-size:12px}.subject-name small{font-size:8px}.course-toolbar h3{font-size:25px}.course-toolbar h3 span{font-size:12px}.course-toolbar p{font-size:12px}.select-label{font-size:12px;gap:10px}.select-label select{font-size:12px;min-width:100px}.syllabus ol{grid-template-columns:1fr 1fr}.service-table{min-width:740px}.table-intro{font-size:14px}.service-table h3{font-size:25px}.price{font-size:31px}.service-table td,.service-table tbody th{font-size:12px}.service-table thead p{font-size:11px}.service-foot>span{font-size:11px}.service-foot .text-link{font-size:13px;white-space:nowrap}.faq-section{grid-template-columns:1fr 1.25fr;gap:38px}.faq-section .section-intro{font-size:15px}.faq-list summary{font-size:15px}.faq-list p{font-size:13px}.closing h2{font-size:42px}}
@media(max-width:600px){html{scroll-padding-top:84px}.wrap{padding-left:24px;padding-right:24px}.nav{height:62px;gap:16px}.nav .brand{font-size:22px;flex:1}.nav .button.small{font-size:12px;padding:8px 14px}.nav-toggle{display:block;order:2}.nav .button.small{order:3}.nav nav{display:none;position:absolute;top:61px;left:0;right:0;background:#fffffffa;backdrop-filter:blur(20px);padding:18px 27px 25px;border-bottom:1px solid #d2d2d7;gap:0;align-items:stretch;box-shadow:0 15px 25px #00000008}.nav-open nav{display:flex;flex-direction:column}.nav nav a{font-size:18px;padding:13px 0;font-weight:500}.nav-toggle svg{transition:transform .25s}.nav-open .nav-toggle svg{transform:rotate(180deg)}.hero{padding-top:42px;padding-bottom:46px}.hero-brand{font-size:21px;margin-bottom:18px}.hero h1{font-size:48px;line-height:1.15;letter-spacing:-2.5px;max-width:340px;margin-bottom:22px}.hero h1 span{display:block}.hero-lead{font-size:17px;font-weight:500;line-height:1.7}.hero-actions{gap:24px;margin-top:25px}.hero-actions .button{font-size:15px;padding:12px 21px}.hero-actions .text-link{font-size:16px}.hero-actions .text-link span{font-size:21px}.product-stage{height:575px;margin-top:43px;padding:0;max-width:360px}.desktop-device{display:none}.product-halo{left:-25%;right:-25%;top:15%;bottom:5%;filter:blur(15px)}.phone-device{position:relative;right:auto;bottom:auto;margin:auto;width:265px;height:559px;border:7px solid #242529;border-radius:43px;padding:17px 15px 7px;outline:1px solid #acaeb3;box-shadow:0 5px 5px -4px #0008,0 29px 40px -20px #4e719a55}.phone-top{font-size:10px;margin-bottom:30px;padding:0 7px}.phone-top i{width:73px;height:20px;top:-7px}.phone-app-head{margin:0 5px 21px}.phone-app-head b{font-size:25px}.phone-app-head>span{font-size:10px}.phone-overview{padding:17px;border-radius:17px}.phone-overview>small{font-size:10px}.phone-overview h3{font-size:29px;margin:9px 0 15px;letter-spacing:-.8px}.phone-progress{height:4px;margin-bottom:8px}.phone-overview>span{font-size:9px}.phone-assignment{border-radius:16px;padding:16px;margin-top:12px}.phone-assignment>span{font-size:9px;margin-bottom:11px}.phone-assignment>b{font-size:15px;line-height:1.5}.phone-assignment>small{font-size:9px;margin-top:9px}.phone-assignment a{font-size:11px;padding:10px;border-radius:9px;margin-top:13px}.phone-review{padding:13px;border-radius:14px;margin-top:11px;gap:10px}.phone-review>span{font-size:27px}.phone-review b{font-size:12px}.phone-review small{font-size:9px;margin-top:5px}.phone-bottom{font-size:9px;margin-top:19px}.home-indicator{height:4px;width:78px;margin-top:15px}.hero-specs{gap:20px;align-items:start;margin-top:28px;font-size:10px;line-height:1.6}.hero-specs span{flex:1;max-width:110px}.hero-specs b{font-size:14px;line-height:1.5;margin-bottom:6px;white-space:nowrap}.product-caption{font-size:10px!important;margin-top:24px;padding:0 24px}.arts{padding-top:65px;padding-bottom:46px}.arts .eyebrow{font-size:18px;margin-bottom:14px}.arts h2{font-size:49px;line-height:1.2;letter-spacing:-1.8px}.arts-head>p{font-size:17px;line-height:1.6;margin:24px 0 32px}.arts-image{width:760px;max-width:none;position:relative;left:50%;transform:translateX(-50%)}.arts-labels{grid-template-columns:repeat(3,1fr);gap:25px 10px;margin:35px 0 30px}.arts-labels b{font-size:30px;margin-bottom:9px}.arts-labels small{font-size:11px}.art-note{font-size:10px;line-height:1.7}.method-section{padding:74px 0}.method-section .eyebrow{font-size:18px}.method-section h2{font-size:46px;line-height:1.23;letter-spacing:-1.5px}.method-lead{font-size:17px;line-height:1.7;margin-top:23px}.learning-five{display:flex;justify-content:center;flex-wrap:wrap;gap:27px 0;margin:42px auto 32px}.learning-five>div{flex-basis:33.333%;border:0}.learning-five b{font-size:27px;margin-bottom:10px}.learning-five span{font-size:11px}.method-signature{font-size:11px}.section{padding-top:72px;padding-bottom:72px}h2{font-size:36px;line-height:1.18;letter-spacing:-1.2px}.eyebrow{font-size:18px;margin-bottom:16px}.section-heading{margin-bottom:34px}.section-heading>.section-intro{font-size:16px;line-height:1.65;margin-top:24px}.section-heading>.text-link{font-size:16px;margin-top:23px}.app-section{padding-left:24px;padding-right:24px}.app-grid{grid-template-columns:1fr;gap:34px}.app-story h3{font-size:29px;margin-bottom:18px}.app-story>p{font-size:17px;line-height:1.7;max-width:none}.app-detail{margin:22px 0}.app-detail b{font-size:17px}.app-detail p{font-size:15px;line-height:1.75;max-width:none}.roadmap-note{font-size:11px;line-height:1.7;margin-top:25px;max-width:100%}.practice{border-radius:23px}.practice-top{padding:18px 21px;font-size:12px}.practice-top small{font-size:10px}.practice-body{padding:25px 21px}.question-category{font-size:11px}.practice h3{font-size:24px;line-height:1.6;margin:20px 0 24px}.answer{padding:14px 12px;font-size:14px;gap:12px;border-radius:11px}.answer span{font-size:11px}fieldset{gap:11px;margin-bottom:23px}.practice-actions{gap:18px}.practice-actions .button{padding:12px 18px;font-size:12px}.hint-button{font-size:12px}.practice .caption{font-size:10px;line-height:1.7}.feedback,.hint-box{font-size:12px;padding:14px}.reason{font-size:11px}.reason select{font-size:12px}.subject-tabs{gap:5px;margin-bottom:28px;padding-bottom:20px}.subject-tabs button{gap:11px;padding:13px 3px;border-radius:12px}.subject-art{font-size:31px}.subject-name{font-size:10px;white-space:nowrap}.subject-name small{display:block;font-size:8px;line-height:1;margin-top:7px}.course-toolbar{align-items:start;gap:15px}.course-toolbar h3{font-size:24px}.course-toolbar h3 span{display:block;font-size:12px;margin:8px 0 0}.course-toolbar p{font-size:11px;line-height:1.75;max-width:200px}.select-label{display:block;font-size:11px;white-space:nowrap}.select-label select{display:block;font-size:12px;min-width:85px;margin-top:8px;padding:9px 15px}.seasons{grid-template-columns:1fr 1fr;gap:12px}.season{border-radius:18px;padding:21px 17px;min-height:210px}.season>span{font-size:10px}.season h4{font-size:23px;margin:13px 0 16px}.season p{font-size:12px;line-height:1.75}.syllabus{margin-top:28px;padding-top:23px}.syllabus summary{font-size:12px;line-height:1.7;gap:15px}.syllabus ol{gap:0 22px;margin-top:25px;padding-left:22px}.syllabus li{font-size:10px}.syllabus li::marker{font-size:9px}.syllabus .caption{font-size:10px}.coming{display:block;text-align:center;padding:30px 23px;border-radius:23px}.coming-mark{display:block;font-size:70px;margin:9px 0 25px}.coming h3{font-size:25px;margin:15px 0}.coming p{font-size:15px;line-height:1.7}.coming .text-link{font-size:14px;margin-top:15px}.service-table{min-width:690px}.service-table thead th{padding:10px 18px 28px}.service-table h3{font-size:25px}.tier-label{font-size:13px}.price{font-size:29px}.price small{font-size:11px}.table-intro{font-size:13px}.service-table thead p{font-size:11px}.service-table thead button{font-size:12px;padding:8px 14px}.service-table td,.service-table tbody th{font-size:12px;padding:20px 18px}.service-table tbody th{padding-left:0}.table-scroll-note{display:block;text-align:right;font-size:11px;color:#86868b;margin-top:18px}.service-foot{display:block;margin-top:24px}.service-foot>span{display:block;font-size:11px;line-height:1.8}.service-foot .text-link{font-size:14px;margin-top:18px}.faq-section{grid-template-columns:1fr;gap:35px}.faq-section .section-intro{font-size:16px;margin-top:20px}.faq-list summary{font-size:16px;line-height:1.7}.faq-list details{padding:23px 0}.faq-list p{font-size:14px;line-height:1.85}.closing{padding:48px 25px;margin:0 24px 55px;border-radius:25px}.closing h2{font-size:32px;letter-spacing:-1px;line-height:1.25}.closing>div:last-child{margin-top:28px}.closing .button{font-size:15px;padding:12px 22px}.closing>div:last-child p{font-size:12px;line-height:1.8;margin-top:20px}footer{padding-bottom:28px;gap:22px;flex-wrap:wrap}footer .brand{font-size:22px}footer p{font-size:10px}footer>a:last-child{font-size:11px}dialog{padding:35px 25px;border-radius:24px}dialog h2{font-size:27px}dialog>p{font-size:15px}.dialog-note{font-size:12px}.wechat-contact{padding:18px}.wechat-contact>div{flex-direction:column;align-items:start;gap:16px}.wechat-contact code{font-size:24px}.wechat-contact button{font-size:12px;padding:9px 14px}.wechat-contact small{font-size:11px}.dialog-back{font-size:12px}}
@media(max-width:360px){.hero h1{font-size:43px}.hero-lead{font-size:15px}.hero-specs{gap:10px}.hero-specs b{font-size:12px}.hero-specs span{font-size:9px}.subject-art{font-size:27px}.subject-name{font-size:9px}.practice h3{font-size:22px}.practice-actions{gap:12px}.hint-button{font-size:11px}.practice-actions .button{font-size:11px;padding:11px 15px}.season{padding:19px 13px}.season p{font-size:11px}.arts-labels small{font-size:10px}}
@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}.button,.subject-tabs button,.nav-toggle svg{transition:none}}

.arts-scroll{overflow:hidden}.arts-scroll-note{display:none}@media(min-width:1101px){.phone-device{height:534px}}@media(max-width:600px){.phone-top{margin-bottom:24px}.phone-app-head{margin-bottom:16px}.phone-overview{padding:14px}.phone-overview h3{font-size:26px;margin:7px 0 11px}.phone-assignment{padding:13px}.phone-assignment>span{margin-bottom:8px}.phone-assignment>b{font-size:14px}.phone-assignment>small{margin-top:7px}.phone-assignment a{padding:8px;font-size:10px;margin-top:10px}.phone-review{padding:10px;margin-top:8px}.phone-review b{font-size:11px}.phone-bottom{margin-top:15px}.home-indicator{margin-top:11px}.arts-scroll{overflow-x:auto;scrollbar-width:none;border-radius:0;margin-left:-24px;margin-right:-24px}.arts-scroll::-webkit-scrollbar{display:none}.arts-image{left:0;transform:none;width:760px;max-width:none}.arts-scroll-note{display:block;font-size:11px;color:#86868b;text-align:center;margin:18px 0 0}}
.app-detail p,.faq-list p,.coming p,.service-table thead p,.service-foot>span,.roadmap-note,.caption,.product-caption{color:#6e6e73}.arts .art-note{color:#86868b}
/* A handscroll prologue, built from the original six-art panorama. */
.intro-pending #site-content{visibility:hidden}.intro-playing{overflow:hidden}.cinema-intro{position:fixed;inset:0;height:100svh;z-index:1000;background:#090a0a;color:#eee9df;overflow:hidden;opacity:1;transition:opacity .65s ease}.cinema-intro.leaving{opacity:0;pointer-events:none}.cinema-vignette{position:absolute;inset:0;background:radial-gradient(ellipse at 50% 50%,#6b58391e,transparent 62%),linear-gradient(90deg,#0008,transparent 20%,transparent 80%,#0008);pointer-events:none;z-index:2}.cinema-letterbox{position:absolute;left:0;right:0;height:7vh;background:#040505;z-index:4;pointer-events:none}.cinema-letterbox.top{top:0}.cinema-letterbox.bottom{bottom:0}.intro-topline{position:absolute;top:calc(24px + env(safe-area-inset-top));left:42px;right:42px;z-index:8;display:flex;align-items:center;justify-content:space-between;gap:20px;font-size:12px;letter-spacing:4px;color:#c5bdaf}.intro-topline>span{font-family:'Songti SC','SimSun',serif}.intro-topline button{padding:9px 0;background:none;color:#c9c4ba;font-size:12px;letter-spacing:.6px;display:flex;gap:17px;align-items:center}.intro-topline button:hover{color:#fff}.intro-topline button:focus-visible{outline:1px solid #d5c09d;outline-offset:8px}.intro-heading{position:absolute;top:13.5%;left:0;right:0;text-align:center;z-index:3;animation:intro-heading-in 1.6s ease both;pointer-events:none}.intro-heading p{font-family:'Songti SC','SimSun',serif;font-size:23px;letter-spacing:7px;color:#e4ddcf;margin:0 0 16px;font-weight:400}.intro-heading h2{font-size:12px;letter-spacing:6px;color:#817b71;line-height:1.7;font-weight:400;margin:0}.cinema-stage{position:absolute;top:49%;left:0;right:0;height:1px;perspective:1800px;z-index:3}.scroll-deck{position:absolute;height:var(--paper-height);width:44px;top:0;left:calc(50% - 22px);transform-origin:center center;will-change:width,transform,left;opacity:0}.scroll-shadow{position:absolute;left:15px;right:15px;top:20px;bottom:-26px;background:#000;filter:blur(28px);opacity:.95}.scroll-paper{position:absolute;inset:0;overflow:hidden;background:linear-gradient(90deg,#9d885d,#ded1b1 24px,#e8ddc3 70%,#b9a273);box-shadow:0 0 0 1px #514530,inset 0 2px 8px #fdf7e44a,inset 0 -2px 7px #493d2255}.scroll-paper img{position:absolute;left:22px;top:19px;width:var(--art-width);height:var(--art-height);max-width:none;object-fit:fill;filter:brightness(.94) saturate(.9)}.scroll-sheen{position:absolute;inset:0;background:linear-gradient(90deg,#0000 75%,#0005 96%,#fff1 100%);pointer-events:none;mix-blend-mode:multiply}.scroll-silk{position:absolute;height:16px;left:0;right:0;background:repeating-linear-gradient(90deg,#fff0 0px,#fff0 4px,#ad976f30 5px,#fff0 6px),linear-gradient(#e3d6b9,#c4b18b);border-top:1px solid #f1e8d04d;border-bottom:1px solid #8a714d77}.scroll-silk.top{top:1px}.scroll-silk.bottom{bottom:1px;transform:rotate(180deg)}.scroll-spindle{position:absolute;top:-20px;bottom:-20px;width:31px;border-radius:9px;background:linear-gradient(90deg,#17140f 0%,#4d3c23 13%,#99815c 35%,#c6af81 49%,#84683f 66%,#352719 89%,#100e0b 100%);box-shadow:2px 3px 7px #000b,inset 1px 0 1px #c9b58766;z-index:5}.scroll-spindle.left{left:-14px}.scroll-spindle.right{right:-14px;background:linear-gradient(90deg,#100e0b,#4b3721 14%,#b49a6c 40%,#d2bd92 53%,#8b7048 70%,#281f14);box-shadow:-4px 2px 9px #0009}.scroll-spindle:before,.scroll-spindle:after{content:'';position:absolute;left:-2px;right:-2px;height:14px;border-radius:50%;background:linear-gradient(90deg,#382c1d,#b6a074 47%,#5b482b);box-shadow:0 0 0 1px #17110a}.scroll-spindle:before{top:-4px}.scroll-spindle:after{bottom:-4px}.scroll-spindle i,.scroll-spindle b{position:absolute;left:7px;right:7px;height:17px;background:linear-gradient(90deg,#2d2419,#8c7652,#2f2518);border-radius:5px}.scroll-spindle i{top:-16px}.scroll-spindle b{bottom:-16px}.intro-chapter{position:absolute;bottom:15%;left:0;right:0;z-index:5;display:flex;justify-content:center;align-items:center;gap:24px;text-align:left;pointer-events:none;transition:opacity .4s}.intro-chapter>span{font-family:'Songti SC','SimSun',serif;font-size:64px;line-height:1;color:#b3caff;font-weight:400;text-shadow:0 0 30px #c3af7a0d}.intro-chapter b{display:block;font-family:'Songti SC','SimSun',serif;font-size:22px;font-weight:400;letter-spacing:5px;color:#d3cbbb;line-height:1.6}.intro-chapter small{display:block;font-size:10px;letter-spacing:7px;margin-top:8px;color:#7c7568}.chapter-flash>span,.chapter-flash>div{animation:chapter-in .65s ease both}.intro-signature{position:absolute;bottom:14.5%;left:0;right:0;text-align:center;z-index:5;opacity:0;pointer-events:none;transition:opacity .5s}.intro-signature>span{font-family:'Songti SC','SimSun',serif;font-size:42px;font-weight:400;letter-spacing:13px;color:#e0d9c9}.intro-signature p{font-size:12px;letter-spacing:4px;color:#817a6e;margin:19px 0 0}.intro-bottomline{position:absolute;bottom:24px;left:42px;right:42px;z-index:8}.intro-legend{display:flex;justify-content:center;gap:35px;margin-bottom:22px;font-family:'Songti SC','SimSun',serif;color:#3d3a34;font-size:17px;letter-spacing:1px}.intro-legend span{transition:color .5s}.intro-legend .seen{color:#807665}.intro-legend .current{color:#d7cbb4}.intro-progress{height:1px;width:100%;background:#28241d;overflow:hidden}.intro-progress i{display:block;height:1px;width:100%;transform:scaleX(0);transform-origin:left;background:linear-gradient(90deg,#697fad,#ba7e54,#9274b9,#a68c52,#a56d61,#659d8d)}.intro-replay{display:inline-flex;align-items:center;gap:10px;border-radius:980px;padding:11px 18px;background:#1d1d1f;color:#a1a1a6;font-size:12px;margin-top:25px}.intro-replay:hover{color:#fff;background:#29292c}.featured-course-link{display:flex;align-items:center;justify-content:space-between;gap:30px;padding:27px 30px;border-radius:22px;background:#f5f5f7;margin-top:25px}.featured-course-link strong{display:block;font-size:21px;font-weight:600;line-height:1.5;color:#1d1d1f}.featured-course-link small{display:block;font-size:14px;color:#6e6e73;line-height:1.8;margin-top:7px}.featured-course-link>b{font-size:15px;font-weight:400;white-space:nowrap;color:#0066cc}.featured-course-link>b span{font-size:20px;margin-left:8px}@keyframes intro-heading-in{from{opacity:0;transform:translateY(8px)}to{opacity:1;transform:translateY(0)}}@keyframes chapter-in{from{opacity:0;transform:translateY(5px)}to{opacity:1;transform:translateY(0)}}
@media(max-width:760px){.intro-topline{left:24px;right:24px;top:calc(18px + env(safe-area-inset-top));font-size:10px;letter-spacing:2px}.intro-topline button{font-size:11px;gap:10px}.intro-heading{top:16%}.intro-heading p{font-size:19px;letter-spacing:4px;margin-bottom:13px}.intro-heading h2{font-size:10px;letter-spacing:3px}.cinema-stage{top:47%}.intro-chapter{bottom:18%;gap:20px}.intro-chapter>span{font-size:53px}.intro-chapter b{font-size:19px;letter-spacing:4px}.intro-chapter small{font-size:9px;letter-spacing:6px;margin-top:6px}.intro-signature{bottom:18%}.intro-signature>span{font-size:32px;letter-spacing:10px}.intro-signature p{font-size:10px;letter-spacing:2px;margin-top:17px}.intro-bottomline{left:24px;right:24px;bottom:22px}.intro-legend{font-size:16px;gap:25px;margin-bottom:20px}.cinema-letterbox{height:8vh}.scroll-spindle{width:28px}.scroll-spindle.left{left:-12px}.scroll-spindle.right{right:-12px}.featured-course-link{display:block;padding:23px;border-radius:20px}.featured-course-link strong{font-size:19px}.featured-course-link small{font-size:12px}.featured-course-link>b{display:block;margin-top:17px;font-size:14px}}
@media(max-height:540px){.intro-heading{display:none}.cinema-stage{top:45%}.intro-chapter{bottom:13%;gap:13px}.intro-chapter>span{font-size:31px}.intro-chapter b{font-size:14px;letter-spacing:3px}.intro-chapter small{display:none}.intro-signature{bottom:14%}.intro-signature>span{font-size:25px;letter-spacing:9px}.intro-signature p{display:none}.intro-legend{margin-bottom:13px;gap:28px;font-size:13px}.intro-bottomline{bottom:15px}}
@media(prefers-reduced-motion:reduce){.cinema-intro,.intro-chapter,.intro-signature,.intro-legend span{transition:none}.intro-heading,.chapter-flash>span,.chapter-flash>div{animation:none}}
/* An in-depth course page; broad chapters, readable details, one worked example. */
.course-breadcrumb{display:flex;align-items:center;gap:12px;font-size:12px;line-height:1.8;color:#86868b;padding-top:24px;padding-bottom:20px}.course-breadcrumb a{color:#6e6e73}.course-breadcrumb a:hover{color:#0066cc}.course-detail{padding:65px 0 100px}.course-detail-heading{text-align:center;max-width:950px;margin:0 auto 60px}.course-detail-heading .eyebrow{font-family:'Songti SC','SimSun',serif;color:#0071e3;font-size:23px;font-weight:500;margin-bottom:25px}.course-detail-heading h1{font-size:66px;line-height:1.17;letter-spacing:-2.7px;font-weight:700;margin:0}.course-detail-heading h1 span{color:#86868b}.course-detail-lead{font-size:26px;font-weight:600;line-height:1.5;margin:28px 0 18px}.course-detail-intro{font-size:20px;font-weight:500;color:#6e6e73;line-height:1.8;margin:0}.course-detail-actions{display:flex;align-items:center;justify-content:center;gap:30px;margin-top:32px}.course-detail-actions .text-link{font-size:17px}.course-detail-facts{display:grid;grid-template-columns:repeat(4,1fr);gap:25px;background:#f5f5f7;border-radius:28px;padding:35px;margin:0 0 90px}.course-detail-facts>div{border-right:1px solid #d2d2d7;padding:0 15px}.course-detail-facts>div:last-child{border:0}.course-detail-facts dt{font-size:12px;color:#86868b;line-height:1.5;margin-bottom:12px}.course-detail-facts dd{margin:0}.course-detail-facts strong{font-size:27px;display:block;line-height:1.4;font-weight:600;letter-spacing:-1px;white-space:nowrap}.course-detail-facts dd span{font-size:12px;color:#6e6e73;display:block;line-height:1.8;margin-top:10px}.course-detail-fit{display:grid;grid-template-columns:.85fr 1.15fr;gap:90px;align-items:start;margin-bottom:60px}.course-detail-fit .eyebrow{font-size:19px}.course-detail h3{font-size:40px;line-height:1.25;font-weight:600;letter-spacing:-1.3px;margin:0}.course-detail-fit-copy p{font-size:18px;color:#6e6e73;line-height:1.9;margin:0 0 20px}.course-detail-outcomes{display:grid;grid-template-columns:repeat(3,1fr);gap:28px;margin-bottom:100px}.course-detail-outcomes article{border-top:1px solid #d2d2d7;padding-top:25px}.course-detail-outcomes article>span{font-size:13px;color:#0071e3}.course-detail-outcomes h3{font-size:24px;line-height:1.5;letter-spacing:-.6px;margin:17px 0 14px}.course-detail-outcomes p{font-size:16px;line-height:1.85;color:#6e6e73;margin:0}.course-detail-subheading{margin-bottom:38px}.course-detail-subheading .eyebrow{font-size:19px}.course-detail-subheading h3{font-size:43px;line-height:1.25;letter-spacing:-1.4px}.course-detail-subheading>p:last-child{color:#6e6e73;font-size:17px;line-height:1.85;margin:22px 0 0;max-width:750px}.course-syllabus{margin-top:35px}.course-unit-list{border-top:1px solid #d2d2d7}.course-unit{border-bottom:1px solid #d2d2d7;padding:0}.course-unit summary{display:flex;align-items:center;gap:35px;padding:27px 0;list-style:none;cursor:pointer}.course-unit summary::-webkit-details-marker{display:none}.course-unit-number{font-size:14px;color:#86868b;min-width:65px}.course-unit summary strong{display:block;font-size:23px;font-weight:600;line-height:1.5;letter-spacing:-.6px}.course-unit summary small{display:block;font-size:13px;color:#86868b;margin-top:9px;line-height:1.6}.course-unit-toggle{margin-left:auto;color:#86868b;font-size:20px}.course-unit[open] .course-unit-toggle{transform:rotate(45deg)}.course-lesson-list{list-style:none;margin:0 0 30px;padding:0 0 0 100px;display:grid;grid-template-columns:1fr 1fr;gap:25px 35px}.course-lesson-list li{display:flex;align-items:start;gap:17px}.course-lesson-list li>span{font-size:12px;color:#a0a0a5;margin-top:6px}.course-lesson-list h4{font-size:17px;line-height:1.7;font-weight:500;margin:0 0 9px}.course-lesson-list p{font-size:14px;color:#6e6e73;line-height:1.8;margin:0}.course-plan-label{font-size:10px;color:#bf4800;background:#fff3e7;white-space:nowrap;padding:4px 6px;display:inline-block;margin-left:5px;vertical-align:middle;border-radius:5px;font-weight:400}.course-detail-note{font-size:12px;line-height:1.9;color:#86868b;margin:24px 0 0;max-width:1000px}.course-rhythm{margin-top:100px;display:grid;grid-template-columns:.85fr 1.15fr;gap:90px;align-items:start}.course-timeline{list-style:none;margin:0;padding:0}.course-timeline li{display:flex;align-items:start;gap:28px;padding:22px 0;border-top:1px solid #d2d2d7}.course-timeline li:last-child{border-bottom:1px solid #d2d2d7}.course-time{font-size:11px;line-height:1.8;color:#0071e3;white-space:nowrap;margin-top:4px;min-width:95px;font-variant-numeric:tabular-nums}.course-timeline h4{font-size:18px;line-height:1.6;font-weight:600;letter-spacing:-.5px;margin:0 0 8px}.course-timeline p{font-size:14px;color:#6e6e73;line-height:1.9;margin:0}.course-timeline-break .course-time{color:#9ca2aa}.course-timeline-break h4{color:#86868b}.course-sample{margin-top:100px;border-radius:30px;background:#f5f5f7;padding:50px}.course-sample-layout{display:grid;grid-template-columns:1fr 1fr;gap:55px;align-items:start}.course-sample-problem{background:#fff;border-radius:22px;padding:28px}.course-sample-label{font-size:13px;color:#86868b}.course-formula{font-size:25px;font-weight:600;letter-spacing:-1px;line-height:1.6;margin:18px 0 10px;white-space:nowrap}.course-formula sup{font-size:14px}.course-domain{font-size:13px;color:#86868b;margin:0}.course-sample-problem>p:not([class]){font-size:16px;color:#6e6e73;line-height:1.8}.course-sample-result{display:grid;grid-template-columns:1fr 1fr;gap:20px;margin:23px 0 0;padding-top:22px;border-top:1px solid #e5e5ea}.course-sample-result dt{font-size:12px;color:#86868b;margin-bottom:10px}.course-sample-result dd{margin:0;font-size:30px;line-height:1.3;font-weight:600;letter-spacing:-1px}.course-sample-result dd span{display:block;font-size:11px;color:#86868b;line-height:1.8;margin-top:10px;font-weight:400;letter-spacing:0}.course-sample-thinking article{margin:0 0 27px}.course-sample-thinking article>span{color:#0071e3;font-size:12px}.course-sample-thinking h4{font-size:22px;font-weight:600;line-height:1.5;margin:12px 0;letter-spacing:-.6px}.course-sample-thinking p{font-size:16px;color:#6e6e73;line-height:1.85;margin:0}.course-sample-question{border-top:1px solid #d2d2d7;padding-top:22px;font-size:17px!important;color:#1d1d1f!important;line-height:1.8}.course-sample-answer{margin-top:20px}.course-sample-answer summary{display:flex;align-items:center;justify-content:space-between;gap:20px;font-size:14px;color:#0066cc;list-style:none;cursor:pointer}.course-sample-answer summary::-webkit-details-marker{display:none}.course-sample-answer p{margin-top:16px;font-size:14px}.course-function-visual{margin:18px 0 24px}.course-function-visual svg{width:100%;height:auto;display:block}.course-plot-grid{fill:none;stroke:#edf1f7;stroke-width:.8}.course-plot-axes{fill:none;stroke:#c5ccd6;stroke-width:1}.course-plot-curve{fill:none;stroke:#0071e3;stroke-width:2.5}.course-plot-labels{fill:#9ca5b3;font-size:12px;font-family:var(--font)}.course-plot-end{fill:#fff;stroke:#4f9be8;stroke-width:1.8}#course-plot-point{fill:#0071e3;stroke:#fff;stroke-width:3;filter:drop-shadow(0 2px 4px #0071e344)}.course-function-visual label{display:block;font-size:12px;color:#86868b;line-height:1.7;margin:13px 0}.course-function-visual input{width:100%;accent-color:#0071e3;height:22px;cursor:pointer}.course-function-visual output{display:block;color:#0071e3;font-size:13px;line-height:1.8;margin-top:9px;text-align:center;font-variant-numeric:tabular-nums}.course-homework{margin-top:100px}.course-practice-details{border:1px solid #d2d2d7;border-radius:20px;overflow:hidden}.course-practice-details summary{display:flex;align-items:center;justify-content:space-between;gap:25px;padding:25px 30px;font-size:17px;color:#0066cc;list-style:none;cursor:pointer}.course-practice-details summary::-webkit-details-marker{display:none}.course-practice-content{padding:0 30px 30px}.course-practice-content>p{font-size:15px;color:#6e6e73;line-height:1.8}.course-practice-questions{padding-left:23px;margin:25px 0;display:grid;grid-template-columns:1fr 1fr;gap:20px 48px}.course-practice-questions li{font-size:14px;line-height:1.9;color:#6e6e73;padding-left:5px}.course-practice-questions li::marker{color:#a0a0a5;font-size:11px}.course-practice-content .course-detail-note{font-size:12px;margin-top:24px}.course-detail-enrol{margin-top:85px;display:grid;grid-template-columns:1.2fr .8fr;gap:70px;align-items:center;padding:40px;border-radius:25px;background:#f5f5f7}.course-detail-enrol .eyebrow{font-size:16px;line-height:1.6}.course-detail-enrol h3{font-size:30px;line-height:1.5}.course-detail-enrol h3 span{font-size:42px;font-weight:650;margin:0 3px}.course-detail-enrol>div>p:last-child{font-size:14px;color:#6e6e73;line-height:1.9;margin-bottom:0}.course-detail-enrol-actions{display:flex;align-items:flex-start;flex-direction:column;gap:22px}.course-detail-enrol-actions .text-link{font-size:16px}.course-detail-enrol-actions .button{font-size:14px;padding:13px 20px}.course-detail-enrol-actions p{font-size:12px!important;color:#86868b!important;margin:0}
@media(max-width:900px){.course-detail{padding-top:40px}.course-detail-heading h1{font-size:54px}.course-detail-intro{font-size:18px}.course-detail-facts{padding:28px;gap:15px}.course-detail-facts>div{padding:0 6px}.course-detail-facts strong{font-size:23px}.course-detail-facts dd span{font-size:10px}.course-detail-fit{gap:50px}.course-detail h3{font-size:32px}.course-detail-fit-copy p{font-size:16px}.course-detail-outcomes{gap:22px}.course-detail-outcomes h3{font-size:22px}.course-detail-outcomes p{font-size:14px}.course-detail-subheading h3{font-size:35px}.course-rhythm{gap:45px}.course-timeline li{gap:17px}.course-time{font-size:10px;min-width:85px}.course-timeline h4{font-size:16px}.course-timeline p{font-size:13px}.course-sample{padding:32px}.course-sample-layout{gap:30px}.course-sample-problem{padding:23px}.course-formula{font-size:22px}.course-sample-thinking h4{font-size:19px}.course-sample-thinking p{font-size:14px}.course-detail-enrol{gap:40px;padding:32px}.course-detail-enrol h3{font-size:27px}.course-detail-enrol h3 span{font-size:36px}.course-detail-enrol-actions .button{font-size:12px}.course-detail-enrol-actions .text-link{font-size:13px}}
@media(max-width:600px){.course-breadcrumb{font-size:10px;padding-top:20px;padding-bottom:15px;gap:8px}.course-detail{padding-top:28px;padding-bottom:65px}.course-detail-heading{margin-bottom:38px}.course-detail-heading .eyebrow{font-size:20px;margin-bottom:23px}.course-detail-heading h1{font-size:37px;line-height:1.28;letter-spacing:-1.4px}.course-detail-lead{font-size:21px;margin:25px 0 18px;line-height:1.5}.course-detail-intro{font-size:16px;line-height:1.8}.course-detail-intro br{display:none}.course-detail-actions{gap:22px;margin-top:27px}.course-detail-actions .button{font-size:14px;padding:12px 18px}.course-detail-actions .text-link{font-size:14px}.course-detail-facts{grid-template-columns:1fr 1fr;gap:26px 15px;padding:26px 21px;border-radius:23px;margin-bottom:60px}.course-detail-facts>div{border:0;padding:0}.course-detail-facts dt{font-size:11px;margin-bottom:9px}.course-detail-facts strong{font-size:23px;letter-spacing:-.5px}.course-detail-facts dd span{font-size:11px;margin-top:7px;line-height:1.8}.course-detail-fit{grid-template-columns:1fr;gap:25px;margin-bottom:35px}.course-detail-fit .eyebrow{font-size:17px}.course-detail h3{font-size:30px;line-height:1.3;letter-spacing:-1px}.course-detail-fit-copy p{font-size:16px;line-height:1.9;margin-bottom:16px}.course-detail-outcomes{grid-template-columns:1fr;gap:25px;margin-bottom:65px}.course-detail-outcomes article{padding-top:23px}.course-detail-outcomes article>span{font-size:12px}.course-detail-outcomes h3{font-size:23px;margin:13px 0}.course-detail-outcomes p{font-size:15px;line-height:1.9}.course-detail-subheading .eyebrow{font-size:17px}.course-detail-subheading h3{font-size:31px;line-height:1.3}.course-detail-subheading>p:last-child{font-size:16px;margin-top:22px}.course-detail-subheading{margin-bottom:30px}.course-unit summary{gap:17px;padding:24px 0}.course-unit-number{font-size:11px;min-width:45px}.course-unit summary strong{font-size:18px;line-height:1.5;letter-spacing:-.5px}.course-unit summary small{font-size:11px;margin-top:8px}.course-unit-toggle{font-size:17px}.course-lesson-list{grid-template-columns:1fr;padding-left:0;gap:23px;margin:0 0 28px}.course-lesson-list li{gap:16px}.course-lesson-list li>span{font-size:11px;min-width:19px}.course-lesson-list h4{font-size:16px;line-height:1.7;margin-bottom:7px}.course-lesson-list p{font-size:13px;line-height:1.9}.course-plan-label{font-size:9px;padding:3px 5px;margin-left:4px}.course-detail-note{font-size:10px;line-height:1.9;margin-top:22px}.course-rhythm{margin-top:65px;grid-template-columns:1fr;gap:4px}.course-timeline li{gap:18px;padding:21px 0}.course-time{font-size:10px;min-width:85px;margin-top:4px}.course-timeline h4{font-size:16px;line-height:1.65;margin-bottom:7px}.course-timeline p{font-size:13px;line-height:1.9}.course-sample{margin-top:65px;border-radius:23px;padding:30px 20px}.course-sample .course-detail-subheading h3{font-size:28px}.course-sample .course-detail-subheading>p:last-child{font-size:14px}.course-sample-layout{grid-template-columns:1fr;gap:32px}.course-sample-problem{border-radius:19px;padding:22px 19px}.course-sample-label{font-size:12px}.course-formula{font-size:22px;letter-spacing:-.6px}.course-domain{font-size:12px}.course-sample-problem>p:not([class]){font-size:14px}.course-sample-result{gap:20px}.course-sample-result dd{font-size:29px}.course-sample-result dd span{font-size:11px}.course-sample-thinking article{margin-bottom:25px}.course-sample-thinking article>span{font-size:11px}.course-sample-thinking h4{font-size:21px;margin:11px 0}.course-sample-thinking p{font-size:15px;line-height:1.9}.course-sample-question{font-size:16px!important}.course-function-visual label{font-size:11px}.course-function-visual output{font-size:12px}.course-sample-answer summary{font-size:13px}.course-sample-answer p{font-size:13px}.course-homework{margin-top:65px}.course-practice-details{border-radius:18px}.course-practice-details summary{font-size:14px;padding:22px 20px;line-height:1.8;gap:17px}.course-practice-content{padding:0 20px 25px}.course-practice-content>p{font-size:13px}.course-practice-questions{grid-template-columns:1fr;gap:19px;padding-left:20px;margin-top:23px}.course-practice-questions li{font-size:13px;padding-left:3px;line-height:1.9}.course-practice-content .course-detail-note{font-size:10px}.course-detail-enrol{grid-template-columns:1fr;gap:27px;margin-top:65px;border-radius:23px;padding:28px 23px}.course-detail-enrol .eyebrow{font-size:14px}.course-detail-enrol h3{font-size:25px;line-height:1.5}.course-detail-enrol h3 span{font-size:35px}.course-detail-enrol>div>p:last-child{font-size:13px;line-height:1.9}.course-detail-enrol-actions{gap:20px}.course-detail-enrol-actions .text-link{font-size:14px}.course-detail-enrol-actions .button{font-size:13px;padding:12px 18px}.course-detail-enrol-actions p{font-size:11px!important}}

.chapter-flash>span,.chapter-flash>div{animation-duration:.3s}
/* The landscape is a cinematic stage; motion comes from the camera and atmosphere. */
.history-world{position:absolute;inset:0;overflow:hidden;opacity:0;pointer-events:none;z-index:0;background:#121b1b}.history-camera,.history-foreground{position:absolute;left:0;top:0;transform-origin:0 0;will-change:transform}.history-camera img{width:100%;height:100%;max-width:none;display:block;filter:brightness(.87) saturate(.88) contrast(1.04)}.history-foreground{background-size:100% 100%;background-repeat:no-repeat;mask-image:linear-gradient(transparent 55%,#0009 75%,#000 90%);opacity:.28;filter:brightness(.82) saturate(.88)}.history-light{position:absolute;inset:-20%;background:linear-gradient(112deg,transparent 45%,#ffe8b408 48%,transparent 51%,#ffe8b40a 54%,transparent 58%);mix-blend-mode:screen;opacity:.65;pointer-events:none}.history-grade{position:absolute;inset:0;background:linear-gradient(#0008 0%,#0002 24%,transparent 48%,#0002 64%,#0009 86%,#000b 100%)}.history-mist{position:absolute;width:160%;left:-30%;pointer-events:none;will-change:transform}.mist-far{top:24%;height:36%;opacity:.12;background:radial-gradient(ellipse at 17% 60%,#e5e6dc88 0,transparent 36%),radial-gradient(ellipse at 53% 50%,#e9e9e0a0 0,transparent 35%),radial-gradient(ellipse at 83% 60%,#f0ede3a0 0,transparent 31%);filter:blur(14px)}.mist-near{top:48%;height:35%;opacity:.15;background:radial-gradient(ellipse at 22% 50%,#eef1e680 0,transparent 35%),radial-gradient(ellipse at 66% 57%,#e5ebde99 0,transparent 42%);filter:blur(12px)}#history-atmosphere{position:absolute;inset:0;width:100%;height:100%;pointer-events:none}.historical-intro .cinema-vignette{background:radial-gradient(ellipse at 50% 45%,transparent 20%,#0003 77%,#0007 100%);z-index:1}.historical-intro .cinema-letterbox{height:8vh;z-index:4;background:#030404}.historical-intro .intro-heading{top:13%;z-index:4;text-shadow:0 3px 14px #0008}.historical-intro .intro-heading p{font-size:25px;letter-spacing:7px;color:#e8e1d2}.historical-intro .intro-heading h2{font-size:12px;letter-spacing:4px;color:#b0a795}.historical-intro .intro-topline{z-index:10}.historical-intro .intro-topline button{min-height:44px;padding:11px 0}.historical-intro .intro-chapter{bottom:10.5%;z-index:5;text-shadow:0 3px 20px #000d}.historical-intro .intro-chapter b{color:#ebe1cc;font-size:23px;letter-spacing:6px}.historical-intro .intro-chapter small{color:#b3a990;font-size:11px;letter-spacing:5px}.historical-intro .intro-bottomline{bottom:19px}.historical-intro .intro-legend{margin-bottom:14px}.historical-intro .intro-signature{bottom:13%;z-index:5}.historical-intro .intro-signature p{color:#a69b87}.historical-intro .scroll-paper .scroll-landscape{object-fit:cover;filter:brightness(.92) saturate(.9);opacity:1}.historical-intro[data-loading=true] .intro-chapter{opacity:0!important}.historical-intro[data-loading=true] .intro-progress i{animation:history-loading 1.8s ease-in-out infinite;transform:scaleX(.08)}.historical-intro[data-phase=journey] .intro-heading{opacity:.9}.historical-intro[data-phase=scroll] .intro-heading{opacity:.7}.historical-intro[data-phase=finale] .intro-heading{opacity:.85}
@keyframes history-loading{0%,100%{opacity:.2}50%{opacity:.7}}
@media(max-width:760px){.historical-intro .cinema-letterbox{height:8vh}.historical-intro .intro-heading{top:14.5%}.historical-intro .intro-heading p{font-size:19px;letter-spacing:4px}.historical-intro .intro-heading h2{font-size:10px;letter-spacing:2px;color:#b4aa96}.historical-intro .intro-chapter{bottom:12%;gap:19px}.historical-intro .intro-chapter>span{font-size:55px}.historical-intro .intro-chapter b{font-size:20px;letter-spacing:3px}.historical-intro .intro-chapter small{font-size:10px;letter-spacing:4px}.historical-intro .intro-signature{bottom:18%}.historical-intro .intro-signature p{font-size:11px}.history-grade{background:linear-gradient(#0009 0%,#0002 29%,transparent 47%,#0003 63%,#000b 88%,#000c 100%)}.history-foreground{opacity:.18}.history-light{opacity:.45}}
@media(max-height:540px){.historical-intro .intro-heading{display:none}.historical-intro .intro-chapter{bottom:13%;gap:14px}.historical-intro .intro-chapter>span{font-size:32px}.historical-intro .intro-chapter b{font-size:15px}.historical-intro .intro-chapter small{display:none}.historical-intro .intro-signature{bottom:14%}.historical-intro .intro-legend{font-size:12px;margin-bottom:9px}.historical-intro .intro-bottomline{bottom:12px}}
@media(prefers-reduced-motion:reduce){.history-camera,.history-foreground,.history-mist{will-change:auto}.historical-intro[data-loading=true] .intro-progress i{animation:none}}

/* Real film retains its complete composition; the landscape is a media fallback. */
.history-film {
  position: absolute;
  inset: 8vh 0;
  width: 100%;
  height: 84vh;
  display: none;
  object-fit: contain;
  object-position: center;
  background: #080d0d;
  pointer-events: none;
}
.film-playing .history-film { display: block; }
.film-playing .history-camera,
.film-playing .history-foreground,
.film-playing .history-light,
.film-playing .history-mist,
.film-playing #history-atmosphere { display: none; }
.film-playing .history-grade {
  background: linear-gradient(#0005, transparent 30%, transparent 65%, #0007);
}
.film-playing .cinema-vignette {
  background: radial-gradient(ellipse at center, transparent 45%, #0003 100%);
}
.film-playing .intro-heading {
  top: 11px;
}
.film-playing .intro-heading p {
  font-size: 18px;
  letter-spacing: 4px;
  line-height: 1.25;
  margin-bottom: 5px;
}
.film-playing .intro-heading h2 {
  font-size: 9px;
  letter-spacing: 2px;
  line-height: 1.3;
}
@media (max-width: 760px) {
  .film-playing .history-grade {
    background: linear-gradient(#0005, transparent 32%, transparent 62%, #0006);
  }
  .film-playing .intro-heading {
    top: calc(50% - 190px);
  }
  .film-playing .intro-heading p {
    font-size: 19px;
    margin-bottom: 13px;
  }
  .film-playing .intro-heading h2 {
    font-size: 10px;
  }
  .film-playing .intro-chapter {
    bottom: calc(50% - 205px);
  }
}