/*! tailwindcss v4.3.3 | MIT License | https://tailwindcss.com */
@layer properties{@supports (((-webkit-hyphens:none)) and (not (margin-trim:inline))) or ((-moz-orient:inline) and (not (color:rgb(from red r g b)))){*,:before,:after,::backdrop{--tw-border-style:solid;--tw-shadow:0 0 #0000;--tw-shadow-color:initial;--tw-shadow-alpha:100%;--tw-inset-shadow:0 0 #0000;--tw-inset-shadow-color:initial;--tw-inset-shadow-alpha:100%;--tw-ring-color:initial;--tw-ring-shadow:0 0 #0000;--tw-inset-ring-color:initial;--tw-inset-ring-shadow:0 0 #0000;--tw-ring-inset:initial;--tw-ring-offset-width:0px;--tw-ring-offset-color:#fff;--tw-ring-offset-shadow:0 0 #0000}}}@layer theme{:root,:host{--font-sans:-apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", "Noto Sans", Arial, sans-serif, "Apple Color Emoji", "Segoe UI Emoji", "Segoe UI Symbol", "Noto Color Emoji";--font-mono:ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, "Liberation Mono", "Courier New", monospace;--default-font-family:var(--font-sans);--default-mono-font-family:var(--font-mono)}}@layer base{*,:after,:before,::backdrop{box-sizing:border-box;border:0 solid;margin:0;padding:0}::file-selector-button{box-sizing:border-box;border:0 solid;margin:0;padding:0}html,:host{-webkit-text-size-adjust:100%;tab-size:4;line-height:1.5;font-family:var(--default-font-family,-apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", "Noto Sans", Arial, sans-serif, "Apple Color Emoji", "Segoe UI Emoji", "Segoe UI Symbol", "Noto Color Emoji");font-feature-settings:var(--default-font-feature-settings,normal);font-variation-settings:var(--default-font-variation-settings,normal);-webkit-tap-highlight-color:transparent}hr{height:0;color:inherit;border-top-width:1px}abbr:where([title]){-webkit-text-decoration:underline dotted;text-decoration:underline dotted}h1,h2,h3,h4,h5,h6{font-size:inherit;font-weight:inherit}a{color:inherit;-webkit-text-decoration:inherit;-webkit-text-decoration:inherit;-webkit-text-decoration:inherit;-webkit-text-decoration:inherit;text-decoration:inherit}b,strong{font-weight:bolder}code,kbd,samp,pre{font-family:var(--default-mono-font-family,ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, "Liberation Mono", "Courier New", monospace);font-feature-settings:var(--default-mono-font-feature-settings,normal);font-variation-settings:var(--default-mono-font-variation-settings,normal);font-size:1em}small{font-size:80%}sub,sup{vertical-align:baseline;font-size:75%;line-height:0;position:relative}sub{bottom:-.25em}sup{top:-.5em}table{text-indent:0;border-color:inherit;border-collapse:collapse}:-moz-focusring:where(:not(iframe)){outline:auto}progress{vertical-align:baseline}summary{display:list-item}ol,ul,menu{list-style:none}img,svg,video,canvas,audio,iframe,embed,object{vertical-align:middle;display:block}img,video{max-width:100%;height:auto}button,input,select,optgroup,textarea{font:inherit;font-feature-settings:inherit;font-variation-settings:inherit;letter-spacing:inherit;color:inherit;opacity:1;background-color:#0000;border-radius:0}::file-selector-button{font:inherit;font-feature-settings:inherit;font-variation-settings:inherit;letter-spacing:inherit;color:inherit;opacity:1;background-color:#0000;border-radius:0}:where(select:is([multiple],[size])) optgroup{font-weight:bolder}:where(select:is([multiple],[size])) optgroup option{padding-inline-start:20px}::file-selector-button{margin-inline-end:4px}::placeholder{opacity:1}@supports (not ((-webkit-appearance:-apple-pay-button))) or (contain-intrinsic-size:1px){::placeholder{color:currentColor}@supports (color:color-mix(in lab, red, red)){::placeholder{color:color-mix(in oklab, currentcolor 50%, transparent)}}}textarea{resize:vertical}::-webkit-search-decoration{-webkit-appearance:none}::-webkit-date-and-time-value{min-height:1lh;text-align:inherit}::-webkit-datetime-edit{display:inline-flex}::-webkit-datetime-edit-fields-wrapper{padding:0}::-webkit-datetime-edit{padding-block:0}::-webkit-datetime-edit-year-field{padding-block:0}::-webkit-datetime-edit-month-field{padding-block:0}::-webkit-datetime-edit-day-field{padding-block:0}::-webkit-datetime-edit-hour-field{padding-block:0}::-webkit-datetime-edit-minute-field{padding-block:0}::-webkit-datetime-edit-second-field{padding-block:0}::-webkit-datetime-edit-millisecond-field{padding-block:0}::-webkit-datetime-edit-meridiem-field{padding-block:0}::-webkit-calendar-picker-indicator{line-height:1}:-moz-ui-invalid{box-shadow:none}button,input:where([type=button],[type=reset],[type=submit]){appearance:button}::file-selector-button{appearance:button}::-webkit-inner-spin-button{height:auto}::-webkit-outer-spin-button{height:auto}[hidden]:where(:not([hidden=until-found])){display:none!important}}@layer components;@layer utilities{.static{position:static}.block{display:block}.grid{display:grid}.hidden{display:none}.border{border-style:var(--tw-border-style);border-width:1px}.ring{--tw-ring-shadow:var(--tw-ring-inset,) 0 0 0 calc(1px + var(--tw-ring-offset-width)) var(--tw-ring-color,currentcolor);box-shadow:var(--tw-inset-shadow), var(--tw-inset-ring-shadow), var(--tw-ring-offset-shadow), var(--tw-ring-shadow), var(--tw-shadow)}}:root{--background:#080d18;--sidebar:#111a29;--surface:#101824;--surface-elevated:#121b29;--surface-soft:#182235;--surface-hover:#1b273a;--border:#27354a;--border-strong:#34445d;--text-primary:#f7f7f4;--text-secondary:#7f8da3;--accent:#f4474d;--accent-strong:#dc343d;--accent-ink:#fff;--danger:#f4474d;--warning:#eea85a;--focus:#ff7b80;--board-light:#ccd0d3;--board-dark:#222e43;--board-frame:#111a29;--board-border:#34445d;--lightningcss-light: ;--lightningcss-dark:initial;color-scheme:dark;font-synthesis:none;text-rendering:optimizelegibility;font-family:Inter,ui-sans-serif,system-ui,-apple-system,BlinkMacSystemFont,Segoe UI,sans-serif}:root[data-theme=light]{--background:#f3f4f7;--sidebar:#fff;--surface:#fff;--surface-elevated:#fff;--surface-soft:#f0f2f6;--surface-hover:#e7eaf0;--border:#d9dee8;--border-strong:#bcc5d3;--text-primary:#172033;--text-secondary:#667085;--accent:#e94148;--accent-strong:#cf3138;--accent-ink:#fff;--lightningcss-light:initial;--lightningcss-dark: ;color-scheme:light}*{box-sizing:border-box}html{background:var(--background);scroll-behavior:smooth;scrollbar-gutter:stable}body{background:var(--background);min-width:320px;min-height:100vh;color:var(--text-primary);margin:0;overflow-x:hidden}body.dialog-open,body.navigation-open{overflow:hidden}button,input,select,textarea{font:inherit}button,a{-webkit-tap-highlight-color:transparent}a{color:inherit;text-decoration:none}button{color:inherit}img,svg{display:block}:focus-visible{outline:3px solid var(--focus);outline-offset:3px}.skip-link{z-index:120;background:var(--accent);color:var(--accent-ink);border-radius:8px;padding:10px 16px;position:fixed;top:8px;left:8px;transform:translateY(-160%)}.skip-link:focus{transform:translateY(0)}.app-shell{min-height:100vh}.app-sidebar{z-index:60;border-right:1px solid var(--border);background:var(--sidebar);flex-direction:column;width:230px;display:flex;position:fixed;inset:0 auto 0 0;overflow:hidden}.sidebar-brand-row{border-bottom:1px solid var(--border);align-items:center;min-height:64px;padding:0 18px;display:flex}.brand{align-items:center;gap:10px;min-width:0;display:inline-flex}.brand-mark{background:var(--accent);color:#fff;border-radius:10px;flex:none;place-items:center;width:36px;height:36px;font-size:23px;line-height:1;display:grid}.brand-copy{gap:1px;min-width:0;display:grid}.brand-copy strong{letter-spacing:-.02em;font-size:16px}.brand-copy small{color:var(--text-secondary);letter-spacing:.14em;text-transform:uppercase;font-size:9px;font-weight:700}.sidebar-close{cursor:pointer;background:0 0;border:0;border-radius:8px;place-items:center;width:38px;height:38px;margin-left:auto;display:none}.sidebar-close:hover{background:var(--surface-hover)}.sidebar-close svg{width:19px}.sidebar-nav{scrollbar-width:thin;flex:1;min-height:0;padding:18px 10px;overflow-y:auto}.sidebar-nav-label{color:#5f6d81;letter-spacing:.14em;text-transform:uppercase;margin:13px 12px 7px;font-size:9px;font-weight:800;display:block}.sidebar-nav-label:first-child{margin-top:0}.nav-link{min-height:42px;color:var(--text-secondary);border:1px solid #0000;border-radius:8px;align-items:center;gap:11px;padding:0 13px;font-size:13px;font-weight:620;transition:color .14s,background .14s,border-color .14s;display:flex}.nav-link svg{flex:none;width:17px;height:17px}.nav-link:hover{color:var(--text-primary);background:var(--surface-soft)}.nav-link.active{color:var(--accent);border-color:var(--accent)}@supports (color:color-mix(in lab, red, red)){.nav-link.active{border-color:color-mix(in srgb, var(--accent) 10%, transparent)}}.nav-link.active{background:var(--accent)}@supports (color:color-mix(in lab, red, red)){.nav-link.active{background:color-mix(in srgb, var(--accent) 13%, transparent)}}.sidebar-footer{border-top:1px solid var(--border);gap:10px;padding:12px 10px 16px;display:grid}.sidebar-backdrop{display:none}.app-main{min-height:100vh;margin-left:230px}.topbar{z-index:40;border-bottom:1px solid var(--border);background:var(--background);justify-content:space-between;align-items:center;gap:20px;min-height:64px;padding:0 32px;display:flex;position:sticky;top:0}@supports (color:color-mix(in lab, red, red)){.topbar{background:color-mix(in srgb, var(--background) 96%, transparent)}}.topbar-primary{align-items:center;gap:13px;display:flex}.topbar-title{gap:1px;display:grid}.topbar-title span{color:var(--text-secondary);letter-spacing:.12em;text-transform:uppercase;font-size:9px;font-weight:750}.topbar-title strong{font-size:13px}.topbar-action{border:1px solid var(--border);min-height:34px;color:var(--text-secondary);border-radius:8px;align-items:center;gap:8px;padding:0 11px;font-size:12px;font-weight:650;display:inline-flex}.topbar-action:hover{color:var(--text-primary);border-color:var(--border-strong);background:var(--surface-soft)}.topbar-action svg{width:15px}.mobile-menu-button,.mobile-brand{display:none}.page-container{width:100%;min-width:0;max-width:1440px;margin:0 auto;padding:32px}.eyebrow{color:var(--accent);letter-spacing:.08em;text-transform:uppercase;margin-bottom:8px;font-size:10px;font-weight:800;display:inline-block}.page-header{justify-content:space-between;align-items:end;gap:32px;margin-bottom:28px;display:flex}.page-header h1{letter-spacing:-.04em;max-width:820px;margin:0;font-size:clamp(30px,4vw,48px);line-height:1.05}.page-header p{max-width:720px;color:var(--text-secondary);margin:11px 0 0;font-size:14px;line-height:1.6}.page-header-actions{flex-wrap:wrap;gap:10px;display:flex}.section-heading{letter-spacing:-.025em;margin:0;font-size:clamp(20px,3vw,25px)}.section-description{color:var(--text-secondary);margin:6px 0 0;font-size:13px;line-height:1.55}.card{background:var(--surface-elevated);border:1px solid var(--border);box-shadow:none;border-radius:12px}.button{cursor:pointer;border:1px solid #0000;border-radius:8px;justify-content:center;align-items:center;gap:8px;min-height:40px;padding:0 15px;font-size:12px;font-weight:700;transition:background .14s,border-color .14s,color .14s;display:inline-flex}.button:disabled{cursor:not-allowed;opacity:.45}.button-primary{background:var(--accent);color:var(--accent-ink)}.button-primary:hover:not(:disabled){background:var(--accent-strong)}.button-secondary{border-color:var(--border);color:var(--text-primary);background:0 0}.button-secondary:hover:not(:disabled),.button-ghost:hover:not(:disabled){background:var(--surface-hover);border-color:var(--border-strong)}.button-ghost{color:var(--text-secondary);background:0 0}.button-danger{background:var(--danger);color:#fff}.button-sm{min-height:36px;padding:0 12px;font-size:11px}.icon-button{border:1px solid var(--border);cursor:pointer;background:0 0;border-radius:8px;place-items:center;width:40px;height:40px;display:inline-grid}.icon-button:hover{background:var(--surface-hover)}.badge{border:1px solid var(--border);min-height:24px;color:var(--text-secondary);letter-spacing:.04em;text-transform:uppercase;border-radius:6px;align-items:center;gap:5px;padding:0 8px;font-size:9px;font-weight:800;display:inline-flex}.progress-group{gap:8px;display:grid}.progress-label{color:var(--text-secondary);justify-content:space-between;gap:20px;font-size:11px;display:flex}.progress-label strong{color:var(--text-primary)}.progress-track{background:var(--surface-soft);border-radius:99px;height:6px;overflow:hidden}.progress-track span{border-radius:inherit;background:var(--accent);height:100%;display:block}.modal-backdrop{z-index:80;background:#000000b8;place-items:center;padding:16px;display:grid;position:fixed;inset:0}.modal-panel{border:1px solid var(--border-strong);background:var(--surface);border-radius:12px;width:min(100%,520px);max-height:min(90vh,760px);padding:24px;overflow:auto;box-shadow:0 24px 80px #00000073}.modal-header{justify-content:space-between;align-items:start;gap:24px;display:flex}.modal-header h2{margin:0;font-size:22px}.modal-header p{color:var(--text-secondary);margin:7px 0 0;line-height:1.5}.modal-actions{justify-content:flex-end;gap:10px;margin-top:28px;display:flex}.empty-state{text-align:center;color:var(--text-secondary);padding:28px 16px}.empty-state h3{color:var(--text-primary);margin:12px 0 6px}.empty-state p{max-width:420px;margin:0 auto 18px;line-height:1.55}.empty-icon{background:var(--surface-soft);width:44px;height:44px;color:var(--accent);border-radius:10px;place-items:center;margin:auto;display:grid}.toast-region{z-index:100;gap:10px;width:min(380px,100vw - 36px);display:grid;position:fixed;bottom:18px;right:18px}.toast{border:1px solid var(--border-strong);background:var(--surface);border-radius:10px;align-items:center;gap:10px;min-height:54px;padding:12px 12px 12px 16px;display:flex;box-shadow:0 16px 40px #0000004d}.toast>span{flex:1;font-size:14px}.toast button{cursor:pointer;background:0 0;border:0;border-radius:8px;place-items:center;width:34px;height:34px;display:grid}.toast-success>svg{color:var(--accent)}.toast-error>svg{color:var(--danger)}.toast-info>svg{color:var(--focus)}.spin{animation:1s linear infinite spin}@keyframes spin{to{transform:rotate(360deg)}}@media (width<=899px){.app-sidebar{visibility:hidden;pointer-events:none;width:min(290px,100vw - 48px);transition:transform .18s,visibility .18s;transform:translate(-102%);box-shadow:20px 0 60px #00000073}.app-sidebar.sidebar-open{visibility:visible;pointer-events:auto;transform:translate(0)}.sidebar-close{display:grid}.sidebar-backdrop{z-index:50;cursor:pointer;background:#03070eb8;border:0;padding:0;display:block;position:fixed;inset:0}.app-main{margin-left:0}.topbar{min-height:60px;padding:0 20px}.mobile-menu-button{border:1px solid var(--border);cursor:pointer;background:0 0;border-radius:8px;place-items:center;width:38px;height:38px;padding:0;display:inline-grid}.mobile-menu-button svg{width:19px}.mobile-brand{align-items:center;gap:7px;font-size:14px;display:inline-flex}.mobile-brand>span{color:var(--accent);font-size:20px}.topbar-title{display:none}.page-container{padding:24px 20px 48px}}@media (width<=540px){.topbar{padding:0 14px}.topbar-action span{display:none}.topbar-action{justify-content:center;width:36px;padding:0}.page-container{padding:20px 14px 42px}.page-header{flex-direction:column;align-items:start;gap:18px;margin-bottom:24px}.page-header-actions{width:100%}.page-header-actions .button{flex:1}}@media (prefers-reduced-motion:reduce){*,:before,:after{scroll-behavior:auto!important;transition-duration:.01ms!important;animation-duration:.01ms!important;animation-iteration-count:1!important}}@property --tw-border-style{syntax:"*";inherits:false;initial-value:solid}@property --tw-shadow{syntax:"*";inherits:false;initial-value:0 0 #0000}@property --tw-shadow-color{syntax:"*";inherits:false}@property --tw-shadow-alpha{syntax:"<percentage>";inherits:false;initial-value:100%}@property --tw-inset-shadow{syntax:"*";inherits:false;initial-value:0 0 #0000}@property --tw-inset-shadow-color{syntax:"*";inherits:false}@property --tw-inset-shadow-alpha{syntax:"<percentage>";inherits:false;initial-value:100%}@property --tw-ring-color{syntax:"*";inherits:false}@property --tw-ring-shadow{syntax:"*";inherits:false;initial-value:0 0 #0000}@property --tw-inset-ring-color{syntax:"*";inherits:false}@property --tw-inset-ring-shadow{syntax:"*";inherits:false;initial-value:0 0 #0000}@property --tw-ring-inset{syntax:"*";inherits:false}@property --tw-ring-offset-width{syntax:"<length>";inherits:false;initial-value:0}@property --tw-ring-offset-color{syntax:"*";inherits:false;initial-value:#fff}@property --tw-ring-offset-shadow{syntax:"*";inherits:false;initial-value:0 0 #0000}.dashboard{gap:24px;display:grid}.dashboard-hero{border:1px solid var(--border);background:var(--surface);border-radius:12px;grid-template-columns:minmax(0,1fr) minmax(240px,300px);align-items:center;gap:clamp(30px,5vw,70px);min-height:0;padding:30px;display:grid}.hero-copy h1{letter-spacing:-.048em;max-width:720px;margin:0;font-size:clamp(34px,4.2vw,54px);line-height:1.02}.hero-copy>p{max-width:660px;color:var(--text-secondary);margin:14px 0 0;font-size:14px;line-height:1.6}.hero-actions{flex-wrap:wrap;gap:9px;margin-top:22px;display:flex}.hero-proof{color:var(--text-secondary);flex-wrap:wrap;gap:10px 18px;margin-top:17px;font-size:10px;display:flex}.hero-proof span{align-items:center;gap:6px;display:inline-flex}.hero-proof svg{color:var(--accent)}.hero-board-shell{isolation:isolate;border:1px solid color-mix(in srgb, var(--accent) 20%, #34445d);background:#111a29;border-radius:12px;justify-self:end;width:min(100%,300px);padding:8px;position:relative;overflow:hidden;box-shadow:inset 0 0 0 1px #f7f7f408}.hero-board{aspect-ratio:1;background:#182235;border:1px solid #34445d;border-radius:6px;position:relative;overflow:hidden}.hero-square-grid{grid-template-columns:repeat(8,1fr);display:grid;position:absolute;inset:0}.hero-square{display:block}.hero-square:nth-child(16n+1),.hero-square:nth-child(16n+3),.hero-square:nth-child(16n+5),.hero-square:nth-child(16n+7),.hero-square:nth-child(16n+10),.hero-square:nth-child(16n+12),.hero-square:nth-child(16n+14),.hero-square:nth-child(16n+16){background:var(--board-light)}.hero-square:nth-child(16n+2),.hero-square:nth-child(16n+4),.hero-square:nth-child(16n+6),.hero-square:nth-child(16n+8),.hero-square:nth-child(16n+9),.hero-square:nth-child(16n+11),.hero-square:nth-child(16n+13),.hero-square:nth-child(16n+15){background:var(--board-dark)}.hero-last-move,.hero-piece{width:12.5%;height:12.5%;transform:translate3d(calc(var(--hero-file) * 100%), calc(var(--hero-rank) * 100%), 0);position:absolute;top:0;left:0}.hero-last-move{z-index:1;background:color-mix(in srgb, var(--accent) 48%, transparent);box-shadow:inset 0 0 0 1px color-mix(in srgb, var(--accent) 62%, transparent)}.hero-piece{z-index:2;will-change:transform;place-items:center;font-size:clamp(18px,2.8vw,33px);line-height:1;transition:transform .48s cubic-bezier(.4,0,.2,1);display:grid}.hero-piece-white{color:#f7f7f4;text-shadow:0 1px #080d18,0 0 2px #080d18}.hero-piece-black{color:#080d18;text-shadow:0 1px #f7f7f459}.hero-board.is-resetting .hero-piece{transition:none}.hero-board-note{z-index:4;white-space:nowrap;background:#121b29;border:1px solid #34445d;border-radius:7px;align-items:center;gap:9px;max-width:calc(100% - 28px);padding:7px 10px;display:flex;position:absolute;bottom:14px;left:50%;transform:translate(-50%);box-shadow:0 5px 14px #00000052}.hero-board-note span{color:#7f8da3;text-transform:uppercase;letter-spacing:.08em;align-items:center;gap:6px;font-size:9px;display:inline-flex}.hero-board-note strong{color:var(--accent);border-left:1px solid #27354a;padding-left:9px;font-family:ui-monospace,monospace}.hero-turn-dot{width:7px;height:7px;box-shadow:0 0 0 3px color-mix(in srgb, var(--accent) 18%, transparent);border-radius:50%;flex:none;animation:1.35s ease-in-out infinite hero-turn-pulse}.hero-turn-dot-white{background:#f7f7f4;border:1px solid #34445d}.hero-turn-dot-black{background:#080d18;border:1px solid #34445d}@keyframes hero-turn-pulse{50%{box-shadow:0 0 0 5px color-mix(in srgb, var(--accent) 8%, transparent)}}.dashboard-main-grid{grid-template-columns:minmax(0,1.8fr) minmax(280px,.78fr);gap:20px;display:grid}.dashboard-primary-column,.dashboard-side-column{align-content:start;gap:18px;display:grid}.continue-card{border-color:var(--accent);background:var(--accent);color:#fff;grid-template-columns:auto 1fr auto;align-items:center;gap:18px;min-height:142px;padding:20px;display:grid}.continue-card .eyebrow,.continue-copy p{color:#ffffffc2}.continue-icon,.feature-icon,.catalog-icon{width:44px;height:44px;color:var(--accent);background:color-mix(in srgb, var(--accent) 13%, transparent);border-radius:10px;flex:none;place-items:center;display:grid}.continue-icon{color:#fff;background:#ffffff26}.continue-copy h2{letter-spacing:-.025em;margin:0 0 6px;font-size:20px}.continue-copy p{margin:0;font-size:12px;line-height:1.5}.continue-action{color:var(--accent-strong);background:#fff;border-color:#fff}.continue-action:hover{background:#f5f5f3}.feature-grid{grid-template-columns:repeat(2,minmax(0,1fr));gap:18px;display:grid}.catalog-link{height:100%;display:block}.catalog-link .card{height:100%;transition:border-color .15s,background .15s}.catalog-link:hover .card{border-color:var(--border-strong);background:color-mix(in srgb, var(--surface-elevated) 94%, var(--accent) 6%)}.feature-card{min-height:230px;padding:20px}.feature-card-top{justify-content:space-between;align-items:start;gap:14px;margin-bottom:20px;display:flex}.feature-count{color:var(--text-secondary);font-size:10px}.feature-card h2{max-width:360px;margin:0 0 8px;font-size:19px}.feature-card p,.opening-shortcut p{color:var(--text-secondary);margin:0;font-size:12px;line-height:1.55}.study-link{color:var(--accent);align-items:center;gap:6px;margin-top:14px;font-size:12px;font-weight:700;display:inline-flex}.recent-card{overflow:hidden}.panel-heading{border-bottom:1px solid var(--border);justify-content:space-between;align-items:center;gap:20px;min-height:62px;padding:13px 18px;display:flex}.panel-heading h2{margin:0;font-size:14px}.panel-heading p{color:var(--text-secondary);margin:3px 0 0;font-size:10px}.panel-heading>svg{width:17px;color:var(--accent)}.activity-list{display:grid}.activity-row{border-bottom:1px solid var(--border);grid-template-columns:auto 1fr auto;align-items:center;gap:12px;min-height:64px;padding:10px 18px;display:grid}.activity-row:last-child{border-bottom:0}.activity-row:hover{background:var(--surface-soft)}.activity-icon{width:34px;height:34px;color:var(--accent);background:color-mix(in srgb, var(--accent) 10%, transparent);border-radius:8px;place-items:center;display:grid}.activity-icon svg{width:15px}.activity-row>span:nth-child(2){gap:3px;display:grid}.activity-row strong{font-size:12px}.activity-row small,.activity-row time{color:var(--text-secondary);font-size:10px}.progress-card,.opening-shortcut,.daily-principle{padding:20px}.progress-metric{gap:1px;margin:8px 0 14px;display:grid}.progress-metric strong{letter-spacing:-.04em;font-size:32px}.progress-metric span{color:var(--text-secondary);font-size:11px}.progress-divider{background:var(--border);height:1px;margin:19px 0}.opening-shortcut h2{margin:16px 0 4px;font-size:19px}.notation-line{border:1px solid var(--border);background:var(--surface-soft);width:fit-content;color:var(--text-secondary);border-radius:6px;margin-top:14px;padding:6px 9px;font:11px ui-monospace,monospace}.daily-principle{border-color:color-mix(in srgb, var(--accent) 24%, transparent);background:color-mix(in srgb, var(--accent) 5%, var(--surface-elevated))}.daily-principle p{color:var(--text-secondary);margin:4px 0 0;font-size:12px;font-style:italic;line-height:1.6}.play-heading{justify-content:space-between;align-items:end;gap:24px;margin-bottom:22px;display:flex}.play-heading h1,.detail-header h1,.lesson-hero h1{letter-spacing:-.04em;margin:0;font-size:clamp(30px,4vw,46px)}.play-heading p,.detail-header p,.lesson-hero p{color:var(--text-secondary);margin:9px 0 0;line-height:1.55}.play-page,.play-layout,.board-column,.game-panel{min-width:0}.play-page{width:100%}.play-layout{grid-template-columns:minmax(0,1fr);align-items:start;gap:clamp(1.5rem,4vw,2.5rem);display:grid}.board-column{width:min(100%,53.125rem);margin:0 auto}.chessboard-wrap{aspect-ratio:1;width:100%;max-width:100%}.chessboard-disabled{cursor:default}.accessible-square{cursor:pointer;background:0 0;border:0;border-radius:0;width:100%;height:100%;padding:0;display:block;position:relative}.chessboard-disabled .accessible-square{cursor:default}.accessible-square:focus-visible{z-index:5;outline-offset:-4px}.board-caption{width:100%;color:var(--text-secondary);justify-content:space-between;gap:1rem;margin-top:.6875rem;font-size:.75rem;display:flex}.game-panel{grid-template-columns:minmax(0,1fr);gap:1rem;max-height:none;display:grid;position:static;overflow:visible}.status-card{padding:17px}.board-status{min-height:52px;color:var(--accent);align-items:center;gap:13px;display:flex}.board-status>div{gap:2px;display:grid}.board-status span{color:var(--text-secondary);text-transform:uppercase;letter-spacing:.09em;font-size:11px;font-weight:740}.board-status strong{color:var(--text-primary);font-size:16px}.board-status.in-check{color:var(--danger)}.board-status.game-over{color:var(--warning)}.history-card{min-height:0;overflow:hidden}.panel-title{border-bottom:1px solid var(--border);justify-content:space-between;align-items:center;height:58px;padding:0 18px;display:flex}.panel-title h2,.controls-card h2{margin:0;font-size:15px}.panel-title span{color:var(--text-secondary);font-size:11px}.move-history{max-height:340px;padding:8px;font-family:ui-monospace,SFMono-Regular,Consolas,monospace;overflow:auto}.move-row{border-radius:7px;grid-template-columns:34px 1fr 1fr;align-items:center;min-height:37px;padding:0 9px;font-size:13px;display:grid}.move-row:nth-child(odd){background:var(--surface-soft)}.move-row span{color:var(--text-secondary)}.controls-card{padding:18px}.control-grid{grid-template-columns:repeat(2,minmax(0,1fr));gap:9px;margin-top:14px;display:grid}.new-game-control{grid-column:1/-1}@media (width>=56.25rem){.play-layout{grid-template-columns:minmax(0,1fr) clamp(18rem,35vw,22rem);gap:clamp(1rem,2vw,1.5rem)}.board-column{width:min(100%,53.125rem,100dvh - 16rem)}.game-panel{max-height:none;position:sticky;top:5rem;overflow:visible}}@media (width>=56.25rem) and (height<=48rem){.play-heading{margin-bottom:1rem}.play-heading p{display:none}}.promotion-grid{grid-template-columns:repeat(4,minmax(0,1fr));gap:10px;margin-top:22px;display:grid}.promotion-option{border:1px solid var(--border);background:var(--surface-soft);cursor:pointer;border-radius:12px;flex-direction:column;justify-content:center;align-items:center;gap:2px;min-height:112px;display:flex}.promotion-option:hover,.promotion-option.recommended{border-color:color-mix(in srgb, var(--accent) 50%, var(--border));background:color-mix(in srgb, var(--accent) 8%, var(--surface-soft))}.promotion-option>span{font-size:41px;line-height:1}.promotion-option small{color:var(--accent);text-transform:uppercase;font-size:9px}.save-game-form{gap:7px;margin-top:22px;display:grid}.save-game-form label{font-size:13px;font-weight:680}.save-game-form>div{gap:8px;display:flex}.save-game-form input{border:1px solid var(--border);background:var(--surface-soft);min-width:0;height:44px;color:var(--text-primary);border-radius:9px;flex:1;padding:0 12px}.saved-game-list{gap:8px;margin-top:20px;display:grid}.saved-game-row{border:1px solid var(--border);border-radius:10px;justify-content:space-between;align-items:center;gap:12px;padding:12px;display:flex}.saved-game-row>div{align-items:center;gap:7px;display:flex}.saved-game-row>div:first-child{min-width:0;display:grid}.saved-game-row span{color:var(--text-secondary);font-size:11px}.catalog-progress{grid-template-columns:auto minmax(260px,480px);justify-content:space-between;align-items:center;gap:30px;margin-bottom:26px;padding:22px 25px;display:grid}.catalog-progress>div:not(.catalog-icon){display:grid}.catalog-progress strong{font-size:22px}.catalog-progress span{color:var(--text-secondary);font-size:12px}.lesson-grid,.opening-grid,.puzzle-grid{grid-template-columns:repeat(3,minmax(0,1fr));gap:18px;display:grid}.lesson-card{grid-template-columns:auto 1fr auto;gap:18px;min-height:250px;padding:22px;display:grid}.piece-symbol{background:var(--surface-soft);width:58px;height:58px;color:var(--accent);border-radius:15px;place-items:center;font-size:42px;display:grid}.lesson-card-content h2,.opening-card h2,.puzzle-card h2{margin:8px 0;font-size:21px}.lesson-card-content p,.opening-card p,.puzzle-card p{color:var(--text-secondary);margin:0;line-height:1.55}.card-index{color:var(--text-secondary);font:11px ui-monospace,monospace}.card-meta{color:var(--text-secondary);flex-wrap:wrap;justify-content:space-between;gap:8px;margin-top:23px;font-size:11px;display:flex}.card-meta>span{align-items:center;gap:5px;display:inline-flex}.complete-label{color:var(--accent)!important}.card-arrow{color:var(--text-secondary)}.back-link{min-height:40px;color:var(--text-secondary);align-items:center;gap:7px;margin-bottom:18px;font-size:14px;display:inline-flex}.back-link:hover{color:var(--text-primary)}.lesson-hero,.detail-header{justify-content:space-between;align-items:center;gap:30px;margin-bottom:34px;display:flex}.lesson-hero>div:first-child,.detail-header>div:first-child{max-width:760px}.lesson-symbol{border:1px solid var(--border);background:var(--surface-elevated);width:108px;height:108px;color:var(--accent);border-radius:24px;place-items:center;font-size:76px;display:grid}.lesson-info-grid{grid-template-columns:repeat(3,minmax(0,1fr));gap:16px;display:grid}.lesson-info-grid .card,.opening-plans .card{padding:22px}.lesson-info-grid h2,.opening-plans h2{margin:0 0 13px;font-size:17px}.lesson-info-grid ul,.opening-plans ul{color:var(--text-secondary);gap:9px;margin:0;padding-left:18px;font-size:14px;line-height:1.45;display:grid}.lesson-info-grid li svg{color:var(--warning);margin-right:7px;display:inline}.section-block{margin-top:54px}.lesson-challenge-layout,.viewer-layout,.puzzle-layout{grid-template-columns:minmax(380px,1fr) minmax(300px,430px);align-items:start;gap:clamp(22px,4vw,44px);display:grid}.lesson-demo-layout{grid-template-columns:minmax(320px,560px) minmax(260px,1fr);align-items:center;gap:clamp(22px,4vw,44px);display:grid}.demo-copy{padding:24px}.demo-copy h2{margin:2px 0 10px;font-size:23px}.demo-copy p{color:var(--text-secondary);line-height:1.6}.demo-copy>strong{color:var(--accent);margin-top:22px;font-size:14px;display:block}.demo-legend{color:var(--text-secondary);flex-wrap:wrap;gap:14px;margin-top:18px;font-size:12px;display:flex}.demo-legend span{align-items:center;gap:7px;display:inline-flex}.demo-legend i{width:18px;height:18px;display:inline-block}.move-dot{background:radial-gradient(circle, var(--accent) 0 35%, transparent 40%);border-radius:50%}.capture-ring{border:3px solid var(--warning);border-radius:4px}.challenge-panel,.viewer-panel,.puzzle-objective,.hint-card,.explanation-card{padding:23px}.challenge-panel h2,.viewer-panel h2,.puzzle-objective h2{margin:2px 0 10px;font-size:23px}.challenge-panel p,.viewer-panel p,.puzzle-objective p,.hint-card p,.explanation-card p{color:var(--text-secondary);line-height:1.55}.attempt-count{border-top:1px solid var(--border);border-bottom:1px solid var(--border);color:var(--text-secondary);justify-content:space-between;margin-top:24px;padding:12px 0;font-size:13px;display:flex}.attempt-count strong{color:var(--text-primary)}.inline-feedback{border-radius:10px;align-items:flex-start;gap:9px;margin-top:15px;padding:12px;font-size:13px;line-height:1.45;display:flex}.inline-feedback svg{flex:none;width:18px}.inline-feedback.success{color:var(--accent);background:color-mix(in srgb, var(--accent) 9%, transparent)}.inline-feedback.error{color:var(--danger);background:color-mix(in srgb, var(--danger) 9%, transparent)}.challenge-actions{flex-wrap:wrap;gap:9px;margin-top:18px;display:flex}.completion-banner{border-color:color-mix(in srgb, var(--accent) 30%, transparent);align-items:center;gap:14px;margin-top:22px;padding:18px 22px;display:flex}.completion-banner>svg{color:var(--accent)}.completion-banner>div{flex:1;display:grid}.completion-banner span{color:var(--text-secondary);font-size:12px}.principles-card{grid-template-columns:minmax(260px,.8fr) minmax(380px,1.2fr);gap:32px;margin-bottom:28px;padding:27px;display:grid}.principles-intro{gap:16px;display:flex}.principle-icon{background:color-mix(in srgb, var(--accent) 10%, transparent);width:50px;height:50px;color:var(--accent);border-radius:13px;flex:none;place-items:center;display:grid}.principles-intro h2{margin:0 0 7px;font-size:21px}.principles-intro p{color:var(--text-secondary);margin:0;line-height:1.5}.principles-card ul{grid-template-columns:repeat(2,minmax(0,1fr));gap:12px 20px;margin:0;padding:0;list-style:none;display:grid}.principles-card li{color:var(--text-secondary);gap:8px;font-size:13px;line-height:1.45;display:flex}.principles-card li svg{color:var(--accent);flex:none}.opening-card{min-height:280px;padding:23px}.opening-card-top{justify-content:space-between;align-items:center;gap:12px;display:flex}.opening-card-top>span:last-child{color:var(--text-secondary);font-size:11px}.opening-card .notation-line{margin-top:20px}.detail-badges{gap:8px;display:flex}.opening-sequence{flex-wrap:wrap;gap:6px;margin-top:21px;display:flex}.opening-sequence button{border:1px solid var(--border);min-height:34px;color:var(--text-secondary);cursor:pointer;background:0 0;border-radius:8px;padding:0 10px;font:12px ui-monospace,monospace}.opening-sequence button.played{background:var(--surface-soft);color:var(--text-primary)}.opening-sequence button.current{border-color:var(--accent);background:color-mix(in srgb, var(--accent) 12%, transparent);color:var(--accent)}.viewer-progress{color:var(--text-secondary);gap:7px;margin-top:23px;font-size:12px;display:grid}.viewer-progress>div{background:var(--surface-soft);border-radius:99px;height:5px;overflow:hidden}.viewer-progress>div span{border-radius:inherit;background:var(--accent);height:100%;display:block}.viewer-controls{flex-wrap:wrap;gap:8px;margin-top:20px;display:flex}.opening-plans{grid-template-columns:repeat(4,minmax(0,1fr));gap:15px;margin-top:24px;display:grid}.mistake-card h2{color:var(--warning);align-items:center;gap:7px;display:flex}.puzzle-grid{grid-template-columns:repeat(2,minmax(0,1fr))}.puzzle-card{grid-template-columns:auto 1fr;gap:20px;min-height:220px;padding:23px;display:grid}.puzzle-number{color:var(--text-secondary);font:18px ui-monospace,monospace}.puzzle-tags{flex-wrap:wrap;gap:7px;display:flex}.puzzle-rail{gap:13px;display:grid}.puzzle-stats{border-top:1px solid var(--border);color:var(--text-secondary);gap:25px;margin-top:18px;padding-top:14px;font-size:12px;display:flex}.puzzle-stats strong{color:var(--text-primary)}.hint-card h3,.explanation-card h3{align-items:center;gap:8px;margin:0 0 10px;font-size:16px;display:flex}.hint-card h3 svg{color:var(--warning)}.hint-card ol{color:var(--text-secondary);gap:8px;margin:0 0 16px;padding-left:21px;font-size:13px;line-height:1.45;display:grid}.success-copy{color:var(--accent)!important}.settings-layout{grid-template-columns:repeat(2,minmax(0,1fr));gap:20px;display:grid}.settings-section{padding:23px}.settings-section-title{align-items:flex-start;gap:13px;margin-bottom:12px;display:flex}.settings-section-title>svg{color:var(--accent)}.settings-section-title h2{margin:0 0 4px;font-size:18px}.settings-section-title p,.setting-row p{color:var(--text-secondary);margin:0;font-size:12px;line-height:1.45}.setting-row{border-top:1px solid var(--border);justify-content:space-between;align-items:center;gap:22px;min-height:75px;display:flex}.setting-row label,.setting-label{font-size:14px;font-weight:680}.setting-row select{border:1px solid var(--border);background:var(--surface);min-width:140px;height:40px;color:var(--text-primary);border-radius:9px;padding:0 34px 0 11px}.switch{border:1px solid var(--border-strong);background:var(--surface-soft);cursor:pointer;border-radius:99px;flex:none;width:50px;height:29px;padding:3px}.switch span{background:var(--text-secondary);border-radius:50%;width:21px;height:21px;transition:transform .15s,background .15s;display:block}.switch.on{background:color-mix(in srgb, var(--accent) 20%, transparent);border-color:var(--accent)}.switch.on span{background:var(--accent);transform:translate(19px)}.danger-zone{border-color:color-mix(in srgb, var(--danger) 25%, transparent);grid-column:1/-1}.danger-zone .settings-section-title>svg{color:var(--danger)}.reset-grid{border-top:1px solid var(--border);flex-wrap:wrap;gap:9px;padding-top:14px;display:flex}.not-found{text-align:center;flex-direction:column;align-items:center;max-width:720px;margin:70px auto;padding:56px 24px;display:flex}.not-found>span{color:var(--accent);letter-spacing:.18em;font:12px ui-monospace,monospace}.not-found>svg{color:var(--text-secondary);margin:20px 0}.not-found h1{margin:0;font-size:clamp(30px,5vw,46px)}.not-found p{color:var(--text-secondary);margin:12px 0 24px}.fatal-error{text-align:center;flex-direction:column;justify-content:center;align-items:center;min-height:100vh;padding:32px;display:flex}.fatal-error>svg{color:var(--danger)}.fatal-error h1{margin:20px 0 8px;font-size:clamp(30px,5vw,48px)}.fatal-error p{max-width:560px;color:var(--text-secondary);margin:0 0 24px;line-height:1.6}@media (width<=1100px){.dashboard-hero{grid-template-columns:minmax(0,1fr) minmax(230px,270px)}.dashboard-main-grid{grid-template-columns:minmax(0,1.45fr) minmax(270px,.75fr)}.lesson-challenge-layout,.viewer-layout,.puzzle-layout{grid-template-columns:minmax(400px,1fr) 330px}.opening-plans,.lesson-grid,.opening-grid{grid-template-columns:repeat(2,minmax(0,1fr))}}@media (width<=900px){.dashboard-hero{grid-template-columns:1fr;padding:24px}.hero-board-shell{justify-self:center;width:min(100%,360px)}.dashboard-main-grid,.lesson-challenge-layout,.lesson-demo-layout,.viewer-layout,.puzzle-layout{grid-template-columns:1fr}.dashboard-side-column{grid-template-columns:repeat(2,minmax(0,1fr))}.daily-principle{grid-column:1/-1}.lesson-info-grid,.principles-card{grid-template-columns:1fr}.viewer-layout>.chessboard-wrap,.puzzle-layout>.chessboard-wrap,.lesson-challenge-layout>.chessboard-wrap,.lesson-demo-layout>.chessboard-wrap{width:min(100%,680px);margin:0 auto}}@media (width<=650px){.dashboard{gap:18px}.dashboard-hero{gap:28px;padding:20px}.hero-copy h1{font-size:clamp(32px,10vw,44px)}.hero-actions{grid-template-columns:1fr;display:grid}.hero-actions .button{width:100%}.hero-board-note{bottom:12px}.continue-card{grid-template-columns:auto 1fr}.continue-card>.button{grid-column:1/-1;width:100%}.feature-grid,.dashboard-side-column,.settings-layout,.lesson-grid,.opening-grid,.puzzle-grid{grid-template-columns:1fr}.daily-principle{grid-column:auto}.activity-row{grid-template-columns:auto 1fr}.activity-row time{grid-column:2}.play-heading{flex-direction:column;align-items:start}.game-panel{grid-template-columns:1fr}.history-card{grid-row:auto}.control-grid{grid-template-columns:1fr}.promotion-grid{grid-template-columns:repeat(2,minmax(0,1fr))}.save-game-form>div{flex-direction:column}.saved-game-row{flex-direction:column;align-items:flex-start}.catalog-progress{grid-template-columns:1fr;gap:16px}.lesson-card{grid-template-columns:auto 1fr}.lesson-card .card-arrow{display:none}.lesson-hero,.detail-header{align-items:flex-start}.lesson-symbol{border-radius:18px;width:72px;height:72px;font-size:50px}.completion-banner{flex-wrap:wrap;align-items:flex-start}.completion-banner .button{width:100%}.principles-card ul,.opening-plans,.puzzle-card{grid-template-columns:1fr}.setting-row{min-height:90px}.setting-row select{min-width:122px}}