/*! 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-rotate-x:initial;--tw-rotate-y:initial;--tw-rotate-z:initial;--tw-skew-x:initial;--tw-skew-y:initial;--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;--tw-blur:initial;--tw-brightness:initial;--tw-contrast:initial;--tw-grayscale:initial;--tw-hue-rotate:initial;--tw-invert:initial;--tw-opacity:initial;--tw-saturate:initial;--tw-sepia:initial;--tw-drop-shadow:initial;--tw-drop-shadow-color:initial;--tw-drop-shadow-alpha:100%;--tw-drop-shadow-size:initial}}}@layer theme{:root,:host{--font-sans:"Segoe UI", system-ui, sans-serif;--font-mono:Consolas, "Liberation Mono", monospace;--spacing:.25rem;--default-transition-duration:.15s;--default-transition-timing-function:cubic-bezier(.4, 0, .2, 1);--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{.visible{visibility:visible}.absolute{position:absolute}.fixed{position:fixed}.static{position:static}.block{display:block}.flex{display:flex}.hidden{display:none}.inline{display:inline}.inline-block{display:inline-block}.table{display:table}.min-w-0{min-width:0}.transform{transform:var(--tw-rotate-x,) var(--tw-rotate-y,) var(--tw-rotate-z,) var(--tw-skew-x,) var(--tw-skew-y,)}.resize{resize:both}.flex-wrap{flex-wrap:wrap}.items-center{align-items:center}.justify-between{justify-content:space-between}.justify-center{justify-content:center}.gap-2{gap:calc(var(--spacing) * 2)}.gap-3{gap:calc(var(--spacing) * 3)}.shadow{--tw-shadow:0 1px 3px 0 var(--tw-shadow-color,#0000001a), 0 1px 2px -1px var(--tw-shadow-color,#0000001a);box-shadow:var(--tw-inset-shadow), var(--tw-inset-ring-shadow), var(--tw-ring-offset-shadow), var(--tw-ring-shadow), var(--tw-shadow)}.shadow\!{--tw-shadow:0 1px 3px 0 var(--tw-shadow-color,#0000001a), 0 1px 2px -1px var(--tw-shadow-color,#0000001a)!important;box-shadow:var(--tw-inset-shadow), var(--tw-inset-ring-shadow), var(--tw-ring-offset-shadow), var(--tw-ring-shadow), var(--tw-shadow)!important}.blur{--tw-blur:blur(8px);filter:var(--tw-blur,) var(--tw-brightness,) var(--tw-contrast,) var(--tw-grayscale,) var(--tw-hue-rotate,) var(--tw-invert,) var(--tw-saturate,) var(--tw-sepia,) var(--tw-drop-shadow,)}.filter\!{filter:var(--tw-blur,) var(--tw-brightness,) var(--tw-contrast,) var(--tw-grayscale,) var(--tw-hue-rotate,) var(--tw-invert,) var(--tw-saturate,) var(--tw-sepia,) var(--tw-drop-shadow,)!important}.transition{transition-property:color,background-color,border-color,outline-color,text-decoration-color,fill,stroke,--tw-gradient-from,--tw-gradient-via,--tw-gradient-to,opacity,box-shadow,transform,translate,scale,rotate,filter,-webkit-backdrop-filter,backdrop-filter,display,content-visibility,overlay,pointer-events;transition-timing-function:var(--tw-ease,var(--default-transition-timing-function));transition-duration:var(--tw-duration,var(--default-transition-duration))}}.graphic-caption{font:10px var(--font-mono);letter-spacing:1px;color:#b6ccd6;justify-content:space-between;align-items:center;gap:12px;margin-bottom:22px;display:flex}.graphic-caption b{color:#b5d9ff;font-size:20px}.address-blocks{grid-template-columns:repeat(4,minmax(0,1fr));gap:7px;display:grid}.address-blocks>div{text-align:center;font:27px var(--font-mono);color:#d3edff;background:#294c6b;border-top:3px solid #8fc5f0;border-radius:4px;padding:15px 3px 12px}.address-blocks small{letter-spacing:1px;margin-top:9px;font-size:9px;display:block}.address-blocks>.host-block{color:#ffd6ad;background:#554335;border-color:#f3b478}.address-brackets{font:9px var(--font-mono);text-align:center;letter-spacing:.5px;grid-template-columns:3fr 1fr;gap:9px;margin-top:9px;display:grid}.address-brackets span{color:#b5d9ff;border-top:1px solid #779dc9;padding-top:9px}.bits-panel{text-align:left;color:#dce9ed;background:#192941;border-radius:12px;margin:24px 0 0;padding:22px}.bits-heading{justify-content:space-between;align-items:center;gap:12px;display:flex}.bits-heading .eyebrow{color:#9fbec9;margin-bottom:5px;font-size:9px}.bits-heading h3{color:#f5fafc;letter-spacing:-.3px;font-size:18px;font-weight:600}.prefix-chip{font:21px var(--font-mono);color:#b5d9ff;background:#304a6c;border-radius:5px;padding:6px 10px}.prefix-control label{color:#c4d7df;justify-content:space-between;font-size:12px;display:flex}.prefix-control input{accent-color:#8fc5f0;cursor:pointer;width:100%;margin:0;display:block}.prefix-control>div{color:#adc5d0;justify-content:space-between;gap:8px;font-size:10px;display:flex}.bit-rows{background:#111f34;border-radius:6px;grid-template-columns:repeat(4,minmax(0,1fr));gap:4px;margin:22px 0 18px;padding:4px;display:grid}.bit-rows button{color:#b5c9d3;border-radius:4px;padding:7px 2px;font-size:12px}.bit-rows button[aria-pressed=true]{color:#fff;background:#365477;box-shadow:inset 0 -2px #8fc5f0}.bits-value{flex-wrap:wrap;justify-content:space-between;align-items:center;gap:8px;display:flex}.bits-value>span{color:#b7cbd3;font-size:12px}.bits-value strong{color:#f2f7fa;font:22px var(--font-mono)}.bit-legend{flex-wrap:wrap;gap:18px;margin:22px 0 10px;font-size:10px;display:flex}.bit-legend>span{align-items:center;gap:6px;display:flex}.bit-legend b{color:#b9ced7;margin-left:3px;font-weight:500}.bit-legend i{border-radius:2px;width:8px;height:8px}.prefix-strip{grid-template-columns:repeat(32,minmax(0,1fr));gap:2px;margin-bottom:20px;display:grid}.prefix-strip span{height:6px}.prefix-strip span:nth-child(8n){margin-right:3px}.octets{grid-template-columns:repeat(2,minmax(0,1fr));gap:16px 20px;display:grid}.octet{min-width:0}.octet-title{color:#aec5d0;justify-content:space-between;align-items:center;margin-bottom:7px;display:flex}.octet-title>span{font:9px var(--font-mono);letter-spacing:1px}.octet-title>strong{font:16px var(--font-mono);color:#e8f0f4}.bit-cells{grid-template-columns:repeat(8,minmax(0,1fr));gap:3px;display:grid}.bit-cells>span{text-align:center;border-radius:3px;flex-direction:column;min-width:0;display:flex;overflow:hidden}.bit-cells .is-network{color:#c8e8ff;background:#294c6b;border:1px solid #467798}.bit-cells .is-host{color:#ffe0bd;background:#594431;border:1px solid #977049}.bit-cells .bit-boundary{border-left:3px solid #ffcf96}.bit-cells b{font:17px var(--font-mono);padding:7px 0}.bit-cells small{font:8px var(--font-mono);background:#0002;padding:4px 0}.bits-explanation{color:#b9cdd6;margin-top:17px;font-size:11px;line-height:1.7}.bits-panel :focus-visible{outline-color:#9eebd3}.subnet-summary{border-top:1px solid #3a525d;margin-top:22px;padding-top:20px}.range-heading{flex-wrap:wrap;justify-content:space-between;align-items:center;gap:6px 14px;display:flex}.range-heading>span{letter-spacing:1px;color:#acc5d0;font-size:9px}.range-heading strong{font:16px var(--font-mono);color:#d5e6ff}.usable-range{background:#284465;border-left:3px solid #8fc5f0;border-radius:4px;margin:16px 0;padding:16px}.usable-range>span{color:#c8e2fa;font-size:12px}.usable-range>div{flex-wrap:wrap;align-items:center;gap:6px 12px;margin-top:8px;display:flex}.usable-range strong{color:#f1f7ff;font:20px var(--font-mono)}.usable-range div>span{color:#c8e2fa;font-size:12px}.subnet-numbers{grid-template-columns:1fr 1fr 1.3fr;gap:12px;display:grid}.subnet-numbers strong{font:17px var(--font-mono);color:#f4d0ac;overflow-wrap:anywhere;display:block}.subnet-numbers span{color:#b7cbd5;margin-top:5px;font-size:10px;display:block}.range-rule{color:#b7cbd5;margin-top:14px;font-size:11px}.subnet-reference{border-top:1px solid #3a525d;flex-wrap:wrap;justify-content:space-between;align-items:center;gap:8px;margin-top:20px;padding-top:18px;display:flex}.subnet-reference label{align-items:center;gap:10px;font-size:12px;display:flex}.subnet-reference select{color:#e9f5f8;background:#294653;border:1px solid #587583;border-radius:5px;min-width:72px;padding:6px}.subnet-reference>span{font:13px var(--font-mono);color:#b7cbd5}.subnet-count{align-items:center;gap:16px;margin:15px 0 20px;display:flex}.subnet-count>strong{font:32px var(--font-mono);color:#acd5ff;overflow-wrap:anywhere}.subnet-count span{color:#e9f5f8;font-size:12px}.subnet-count small{color:#b7cbd5;margin-top:4px;font-size:10px;display:block}.subnet-table-scroll{overflow-x:auto}.subnet-table{border-collapse:collapse;white-space:nowrap;text-align:left;width:100%}.subnet-table caption{text-align:left;color:#b7cbd5;white-space:normal;margin-bottom:10px;font-size:10px}.subnet-table thead th{color:#b7cbd5;border-bottom:1px solid #526976;padding:10px 8px;font-size:9px;font-weight:500}.subnet-table tbody th,.subnet-table td{font:10px var(--font-mono);border-bottom:1px solid #2c4654;padding:12px 8px}.subnet-table small{font:9px var(--font-sans);margin-top:4px;display:block}.subnet-pages{justify-content:space-between;align-items:center;gap:8px;margin-top:8px;font-size:10px;display:flex}.subnet-pages button{color:#c3dcff}.subnet-pages>span{color:#b7cbd5;text-align:center}@media (width<=480px){.subnet-numbers{grid-template-columns:1fr 1fr}.subnet-numbers>div:last-child{grid-column:1/-1}.usable-range strong{font-size:17px}.subnet-count{flex-wrap:wrap;gap:8px}.subnet-count>strong{font-size:27px}}@media (width<=1000px){.intro-graphic{padding:20px 14px}.address-blocks>div{font-size:22px}.address-blocks small{letter-spacing:0}}@media (width<=740px){.intro-graphic{width:100%;max-width:none}.address-blocks>div{font-size:25px}}@media (width<=480px){.bits-panel{padding:16px 12px}.octets{grid-template-columns:1fr}.bit-cells b{font-size:19px}.bit-cells small,.bit-rows button{font-size:10px}.prefix-control>div{font-size:9px}.bits-value strong{font-size:19px}}.site-header{background:#fafbfe;border-bottom:1px solid #d5deeb}.header-inner{justify-content:space-between;align-items:center;gap:16px;max-width:1180px;margin:auto;padding:22px 24px;display:flex}.brand{color:#263e65;letter-spacing:-.7px;align-items:center;gap:10px;font-size:20px;font-weight:750;text-decoration:none;display:flex}.brand-light{margin-left:3px;font-weight:400}.brand-icon{color:#deebff;width:34px;height:34px;font:26px var(--font-mono);background:#3159a3;border-radius:9px;place-items:center;display:grid}.header-label{letter-spacing:1.3px;color:#64776d;align-items:center;gap:18px;font-size:10px;display:flex}.ipv4-tag{letter-spacing:.3px;color:#315b48;border:1px solid #cbd8cb;border-radius:5px;padding:5px 9px;font-size:11px}.intro{grid-template-columns:1fr 1fr;align-items:center;gap:48px;padding:22px 0 40px;display:grid}.intro h1{letter-spacing:-1.7px;margin:12px 0 17px;font-size:clamp(34px,3.7vw,46px);line-height:1.13}.cert-tags{gap:7px;margin-top:18px;display:flex}.cert-tags span{letter-spacing:.6px;color:#607493;border:1px solid #d0dcec;border-radius:4px;padding:3px 8px;font-size:10px}.workspace-layout{grid-template-columns:minmax(0,1fr) 294px;align-items:start;gap:24px;display:grid}.settings-card{background:#fff;border:1px solid #d8e0ec;border-radius:12px;margin-bottom:18px;padding:16px 20px}.mode-switch{background:#edf1f8;border-radius:7px;padding:4px;display:flex}.mode-switch button{color:#596e8d;border-radius:5px;flex:1;padding:8px;font-size:13px;font-weight:650}.mode-switch button span{margin-left:8px;font-size:11px;font-weight:400}.mode-switch button[aria-pressed=true]{color:#3159a3;background:#fff;box-shadow:0 1px 4px #1c422212}.mode-switch button:disabled{opacity:1}.settings-grid{grid-template-columns:1fr 1.2fr;gap:18px;margin-top:16px;display:grid}.settings-grid label{color:#4b6182;margin-bottom:5px;font-size:11px;font-weight:650;display:block}.settings-grid select{color:#2c4265;background:#fff;border:1px solid #cbd6e7;border-radius:6px;width:100%;padding:8px 10px;font-size:13px}.settings-grid select:disabled{opacity:.85;background:#f2f5fa}.level-help{color:#5b6d88;margin-top:10px;font-size:11px}.ready-state>p:not(.eyebrow){color:#62718a;margin:12px 0 24px;font-size:14px}.ready-state .ready-detail{margin:17px 0 0!important;font-size:11px!important}.stats-card{background:#e9eff8;border:1px solid #d4dfef;border-radius:12px;padding:23px}.stats-card h2{letter-spacing:-.3px;font-size:16px}.local-dot{color:#597291;align-items:center;gap:5px;font-size:10px;display:inline-flex}.local-dot:before{content:"";background:#6d8dbc;border-radius:50%;width:5px;height:5px}.stat-main strong{letter-spacing:-2px;color:#315182;font-size:46px;font-weight:600;line-height:1.1;display:block}.stat-main>span{color:#627593;margin-top:6px;font-size:12px;display:block}.stat-pair{grid-template-columns:1fr 1fr;gap:12px;margin:22px 0 26px;display:grid}.stat-pair strong{font-size:19px;font-weight:650;display:block}.stat-pair span{color:#627593;margin-top:3px;font-size:10px;display:block}.type-stats{border-top:1px solid #cfdaeb;padding-top:20px}.type-stats h3{letter-spacing:1.3px;color:#596e8d;margin-bottom:16px;font-size:9px;font-weight:650}.type-stat>div:first-child{justify-content:space-between;font-size:11px;display:flex}.stat-track{background:#d3dff0;border-radius:4px;height:4px;margin:7px 0 3px;overflow:hidden}.stat-track>span{background:#6285c3;height:100%;display:block}.type-stat small{color:#596c87;font-size:9px}.review-note{border-top:1px solid #cfdaeb;gap:10px;margin:24px 0 14px;padding-top:18px;display:flex}.review-note>span{font-size:20px}.review-note p{color:#596e8d;font-size:10px}.review-note strong{color:#365177;font-size:11px;font-weight:600}.reset-button{color:#596e8d;text-underline-offset:3px;width:100%;font-size:10px;text-decoration:underline}.exercise-topline{justify-content:space-between;align-items:center;gap:10px;margin-bottom:24px;display:flex}.exercise-badge{color:#3a598c;background:#e8eefb;border-radius:5px;padding:5px 8px;font-size:10px;font-weight:600}.review-badge{color:#936128;font-size:10px}.exercise-counter{color:#60718b;white-space:nowrap;font-size:11px}.question-title{font-family:var(--font-mono);overflow-wrap:anywhere;font-size:clamp(19px,2.1vw,26px);line-height:1.4}.question-prompt{margin-top:13px;font-size:14px}.context-note{color:#5b6d88;background:#eef3fa;border-left:2px solid #8ba7d7;margin-top:18px;padding:12px 14px;font-size:12px}.timer-line{color:#657660;border-bottom:1px solid #e2e8db;justify-content:space-between;align-items:center;gap:10px;margin:-10px 0 18px;padding:10px 0;font-size:11px;display:flex}.timer-line strong{font:16px var(--font-mono);color:#34563c}.leave-button{color:#637565;text-underline-offset:3px;margin-top:22px;font-size:11px;text-decoration:underline}.workspace-note{color:#687766;padding:14px 4px;font-size:10px}.workspace-note>span{margin-right:4px}.storage-warning{color:#7b502a;background:#fff0dd;border-radius:8px;padding:14px;font-size:13px}.session-summary{text-align:center;padding:20px 0}.session-summary>p:not(.eyebrow){color:#677760;margin:8px 0 20px;font-size:13px}.score{color:#23563f;letter-spacing:-3px;margin-top:28px;font-size:72px;font-weight:650;line-height:1}.score span{color:#728767;letter-spacing:-1px;font-size:28px;font-weight:400}.summary-times{border-block:1px solid #dce5d4;justify-content:center;gap:32px;margin:24px 0;padding:18px 0;display:flex}.summary-times strong{font-size:20px;display:block}.summary-times span{color:#6b7e60;font-size:11px}.button-secondary{border:1px solid #bfccbb;border-radius:8px;padding:12px 18px;font-size:13px}footer{color:#65748b;border-top:1px solid #d5deeb;justify-content:space-between;gap:14px;margin-top:36px;padding-top:22px;font-size:10px;display:flex}.skip-link{color:#3159a3;z-index:10;background:#fff;padding:12px;position:absolute;top:-100px;left:12px}.skip-link:focus{top:12px}body{color:#26364c;font-family:var(--font-sans);background:#f1f4f9;margin:0}main{max-width:1180px;margin:auto;padding:32px 24px 60px}h1{letter-spacing:-1.3px;font-size:36px;font-weight:700}h2{letter-spacing:-.5px;font-size:23px;font-weight:650}p{line-height:1.65}button,input,select{font:inherit}button{cursor:pointer}button:disabled{cursor:default;opacity:.6}button,input,select{min-height:46px}:focus-visible{outline-offset:4px;outline:3px solid #4376c4}.exercise-card{background:#fff;border:1px solid #d8e0ec;border-radius:16px;padding:30px}.answer-grid{grid-template-columns:repeat(2,minmax(0,1fr));gap:22px 24px;margin:28px 0;display:grid}.answer-field label{margin-bottom:8px;font-size:14px;font-weight:600;display:block}.answer-field input,.answer-field select{color:#26364c;width:100%;font-family:var(--font-mono);background:#fff;border:1px solid #b6c5dc;border-radius:7px;padding:10px 12px;font-size:15px}.answer-field [aria-invalid=true]{border-color:#b44c30}.answer-field small{margin-top:5px;font-size:12px;display:block}.field-error,.field-success{margin-top:6px;font-size:13px}.form-footer{flex-wrap:wrap;align-items:center;gap:16px;display:flex}.button-primary{color:#fff;background:#3159a3;border-radius:8px;padding:12px 22px;font-size:14px;font-weight:650}.keyboard-hint{color:#60718b;font-size:12px}kbd{background:#f8faf7;border:1px solid #ccd6ce;border-radius:4px;padding:2px 4px;font-size:11px}.correction{border-top:1px solid #d8e0ec;margin-top:28px;padding-top:24px}.eyebrow{letter-spacing:1.5px;color:#5b7194;margin-bottom:8px;font-size:11px;font-weight:700}.correction ol{margin:20px 0;padding-left:22px;list-style:decimal}.correction li{margin:12px 0;padding-left:6px;font-size:14px;line-height:1.7}@media (width<=600px){main{padding:24px 16px 40px}h1{font-size:28px}.exercise-card{padding:22px 18px}.answer-grid{grid-template-columns:1fr;gap:16px}.keyboard-hint{display:none}}@media (width<=900px){.workspace-layout{grid-template-columns:minmax(0,1fr) 260px;gap:18px}.stats-card{padding:18px}.network-illustration{padding:18px 12px}.diagram-branches{gap:10px}.diagram-branches>div{font-size:10px}.intro{gap:24px}.mode-switch button span{margin-top:3px;margin-left:0;display:block}}@media (width<=740px){.header-label{display:none}.header-inner{padding:18px 20px}.intro{grid-template-columns:1fr;padding-top:4px;padding-bottom:28px}.network-illustration{display:none}.workspace-layout{grid-template-columns:1fr}.settings-grid{gap:12px}.settings-card{padding:14px}.ready-state h2{font-size:21px}.stats-card{padding:24px}.type-stats{grid-template-columns:1fr 1fr;gap:0 20px;display:grid}.type-stats h3{grid-column:1/-1;margin-bottom:3px}footer{flex-direction:column}}.header-inner{padding-top:13px;padding-bottom:13px}main{padding-top:18px;padding-bottom:28px}.intro{grid-template-columns:1.2fr 1fr;gap:26px;padding:4px 0 22px}.intro h1{letter-spacing:-.9px;margin:8px 0 10px;font-size:clamp(25px,2.5vw,32px)}.intro>div>p:not(.eyebrow){font-size:13px}.intro-graphic{box-shadow:none;border-radius:9px;padding:14px 18px}.graphic-caption{margin-bottom:10px;font-size:9px}.address-blocks>div{padding:8px 3px;font-size:21px}.address-blocks small,.address-brackets{margin-top:5px}.address-brackets span{padding-top:5px}.settings-card{border-radius:9px;margin-bottom:12px;padding:10px 14px}.settings-grid{gap:12px;margin-top:10px}.level-help{margin-top:6px}.ready-state{text-align:left;padding:0}.ready-state h2{font-size:19px}.ready-state>p:not(.eyebrow){margin:7px 0 12px;font-size:12px}.ready-state .ready-detail{margin-top:8px!important}.ready-state>.bits-panel{margin-top:18px}.bits-panel{border-radius:8px;padding:16px}.bits-heading h3{font-size:16px}.prefix-control{margin-top:12px}.prefix-control input{min-height:32px}.subnet-summary{margin-top:14px;padding-top:12px}.usable-range{margin:10px 0;padding:10px 12px}.usable-range>div{margin-top:5px}.usable-range strong{font-size:18px}.range-rule{margin-top:9px;font-size:10px}.subnet-reference{margin-top:12px;padding-top:10px}.subnet-reference select{min-height:36px}.subnet-count{margin:8px 0 12px}.subnet-count>strong{font-size:26px}.subnet-details{border:1px solid #3c536e;border-radius:5px}.subnet-details summary{cursor:pointer;color:#c9dfff;padding:11px;font-size:11px}.subnet-details[open] summary{border-bottom:1px solid #3c536e}.subnet-details>.subnet-table-scroll{padding:8px}.subnet-pages{padding:0 8px}.bit-rows{margin:14px 0 10px}.bit-rows button{min-height:38px}.bit-legend{margin-top:12px}.prefix-strip{margin-bottom:12px}.octets{gap:12px}.bit-cells b{padding:4px 0}.bits-explanation{margin-top:10px;font-size:10px}.stats-card{border-radius:9px;padding:18px}.stat-main{margin-top:16px}.stat-main strong{font-size:37px}.stat-pair{margin:16px 0}.type-stats{padding-top:14px}.type-stat{margin-top:10px}.review-note{margin-top:16px;padding-top:12px}.exercise-topline{margin-bottom:14px}.context-note{margin-top:12px;padding:9px 12px}.answer-grid{gap:14px 18px;margin:20px 0}.correction{margin-top:20px;padding-top:18px}.workspace-note{padding:9px 2px}footer{margin-top:20px;padding-top:14px}@media (width>=1100px){.octets{grid-template-columns:repeat(4,minmax(0,1fr));gap:10px}.bit-cells{gap:2px}.bit-cells b{font-size:14px}.bit-cells small{font-size:7px}}@media (width<=740px){main{padding:16px 12px 24px}.intro{grid-template-columns:1fr;gap:12px;padding-bottom:16px}.intro h1{font-size:26px}.workspace-layout{grid-template-columns:1fr}.exercise-card{padding:14px}.bits-panel{padding:13px}.stats-card{padding:16px}.intro-graphic{padding:12px}}:root{--font-sans:"Segoe UI", system-ui, sans-serif;--paper:#f3f0ea;--paper-light:#fffdf9;--ink-human:#1b2d32;--ink-muted:#627278;--teal-human:#176f68;--teal-soft:#d8ece6;--orange-human:#d87747;--line-human:#d5dfda}body{background:var(--paper);color:var(--ink-human)}.site-header{border-bottom:1px solid var(--line-human);background:#fffdf9eb}.header-inner{max-width:1260px;padding:16px 28px}.brand{color:var(--ink-human);letter-spacing:.13em;font-size:17px}.brand-light{color:var(--ink-muted);letter-spacing:.14em;margin-left:8px;font-size:.76em}.brand-icon{background:var(--teal-human);color:#fff;border-radius:11px;width:34px;height:34px;font:700 20px Segoe UI,sans-serif}.header-label{color:var(--ink-muted);letter-spacing:1.1px}.ipv4-tag{color:var(--teal-human);background:#eef6f2;border-color:#b8d1c8}main{max-width:1260px;padding:27px 28px 54px}.intro{background:linear-gradient(135deg,#173f45 0%,#245d5b 62%,#2b6b65 100%);border:1px solid #b9d2c9;border-radius:20px;grid-template-columns:1.12fr .88fr;gap:35px;padding:38px 42px;position:relative;overflow:hidden;box-shadow:0 18px 42px #1a3f411f}.intro:after{content:"";pointer-events:none;background:#f2bf8421;border-radius:50%;width:330px;height:330px;position:absolute;top:-150px;right:-110px}.intro>div{z-index:1;position:relative}.intro .eyebrow{color:#a9e4d6}.intro h1{color:#fff;letter-spacing:-1.8px;margin:11px 0 16px;font-size:clamp(29px,3.6vw,45px)}.intro h1 span{color:#f6c994}.intro>div>p:not(.eyebrow){color:#d7e7e3;font-size:14px}.cert-tags{margin-top:20px}.cert-tags span{color:#e2f1ed;background:#ffffff14;border:1px solid #d0ebe270;border-radius:999px;padding:4px 10px}.intro-graphic{color:var(--ink-human);background:#f7efe3;border:1px solid #dfc9ad;border-radius:15px;padding:24px;box-shadow:0 12px 25px #0c222621}.graphic-caption{color:#6d7a78}.graphic-caption b{color:var(--teal-human)}.address-blocks>div{color:#155c58;background:#d7ebe5;border-top-color:#258174}.address-blocks>.host-block{border-top-color:var(--orange-human);color:#8f4b2d;background:#f3dcc0}.address-brackets span{color:#24756d;border-top-color:#57a69a}.address-brackets span:last-child{color:#a45b35;border-color:#d49a68}.workspace-layout{grid-template-columns:minmax(0,1fr) 296px;gap:22px}.settings-card,.exercise-card{border-color:var(--line-human);background:var(--paper-light);box-shadow:0 8px 22px #1d35380d}.settings-card{border-radius:14px;padding:15px 18px}.mode-switch{background:#e6efeb;border-radius:999px}.mode-switch button{color:#5d716f;border-radius:999px}.mode-switch button[aria-pressed=true]{color:var(--teal-human);box-shadow:0 2px 8px #204e491f}.settings-grid label{color:#526764}.settings-grid select{color:var(--ink-human);background:#fff;border-color:#c1d2cb;border-radius:8px}.settings-grid select:disabled{background:#f0f4f1}.level-help,.keyboard-hint{color:var(--ink-muted)}.exercise-card{border-radius:16px;padding:28px}.ready-state .eyebrow,.eyebrow{color:var(--teal-human)}.ready-state h2,.question-title,.session-summary h2{color:var(--ink-human)}.ready-state>p:not(.eyebrow),.question-prompt{color:#52666b}.button-primary{background:var(--teal-human);border-radius:999px;padding:12px 20px}.button-primary:hover{background:#105d57}.button-secondary{color:var(--ink-human);background:#fff;border-color:#bdd0c7;border-radius:999px}.bits-panel{background:#173e43;border:1px solid #2b6e68;box-shadow:0 10px 24px #14353924}.bits-heading .eyebrow{color:#a8ddd2}.prefix-chip{color:#f4c996;background:#285a5b}.prefix-control input{accent-color:#f1bb82}.bit-rows{background:#112f35}.bit-rows button[aria-pressed=true]{background:#2e6d68;box-shadow:inset 0 -2px #f1bb82}.network-key,.prefix-strip .is-network{background:#74c7b6}.host-key,.prefix-strip .is-host{background:#e8ae78}.bit-cells .is-network{color:#d5f4eb;background:#245e60;border-color:#4a9b91}.bit-cells .is-host{color:#ffe3c6;background:#694a37;border-color:#b87d50}.bit-cells .bit-boundary{border-left-color:#f3c18d}.subnet-summary{border-top-color:#3d6866}.usable-range{background:#255e60;border-left-color:#f2c18d}.subnet-reference{border-top-color:#3d6866}.subnet-reference select{color:#f4f8f4;background:#214f53;border-color:#5b8b84}.subnet-count>strong{color:#f4c78d}.subnet-details{border-color:#4a7d77}.subnet-details[open] summary{border-bottom-color:#4a7d77}.subnet-table .current-subnet{color:#f5fbf8;background:#2b6b68}.stats-card{background:#ece7de;border-color:#d7d0c4;box-shadow:0 8px 22px #2f362f0d}.stats-card h2{color:var(--ink-human)}.local-dot{color:#6b7772}.local-dot:before{background:var(--teal-human)}.stat-main strong{color:var(--teal-human)}.stat-main>span,.stat-pair span,.type-stat small{color:#6c7772}.type-stats{border-top-color:#d6cec2}.type-stats h3{color:#66726f}.stat-track{background:#d4d8cf}.stat-track>span{background:var(--teal-human)}.review-note{border-top-color:#d6cec2}.review-note p{color:#66726f}.review-note strong{color:#285f59}.reset-button,.leave-button{color:#66726f}.exercise-badge{background:var(--teal-soft);color:#1b625b;border-radius:999px}.review-badge{color:#a65c34}.exercise-counter{color:#687874}.context-note{color:#6c625a;background:#f8eee2;border-left-color:#d8945d}.timer-line{color:#5d756c;border-bottom-color:#d7e2dc}.timer-line strong{color:var(--teal-human)}.answer-field label{color:#415a59}.answer-field input,.answer-field select{color:var(--ink-human);background:#fff;border-color:#bfd0c8;border-radius:8px}.answer-field input:focus,.answer-field select:focus{border-color:var(--teal-human)}.answer-field input[readonly]{background:#f0f4f1}.form-footer{border-top-color:#d6e0db}.correction{border-top-color:var(--line-human)}.correction li{color:#43575a}.field-success{color:#146c58}.field-error{color:#ac4b2d}.workspace-note{color:#687773}.storage-warning{color:#815033;background:#f7e7d6}.score{color:var(--teal-human)}.score span{color:#72837d}.summary-times{border-block-color:#d6e0d8}.summary-times span{color:#6c7772}footer{border-top-color:var(--line-human);color:#74827f}.skip-link{background:var(--teal-human);color:#fff}:focus-visible{outline-color:var(--orange-human)}@media (width<=740px){main{padding:18px 16px 40px}.intro{border-radius:16px;padding:28px 24px}.intro h1{font-size:30px}.workspace-layout{gap:14px}}.header-actions{align-items:center;gap:22px;display:flex}.home-link{color:var(--teal-human);white-space:nowrap;font-size:12px;font-weight:650;text-decoration:none}.home-link:hover{color:#a85b35;text-underline-offset:4px;text-decoration:underline}@media (width<=740px){.header-actions{gap:0}.home-link{font-size:11px}}@property --tw-rotate-x{syntax:"*";inherits:false}@property --tw-rotate-y{syntax:"*";inherits:false}@property --tw-rotate-z{syntax:"*";inherits:false}@property --tw-skew-x{syntax:"*";inherits:false}@property --tw-skew-y{syntax:"*";inherits:false}@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}@property --tw-blur{syntax:"*";inherits:false}@property --tw-brightness{syntax:"*";inherits:false}@property --tw-contrast{syntax:"*";inherits:false}@property --tw-grayscale{syntax:"*";inherits:false}@property --tw-hue-rotate{syntax:"*";inherits:false}@property --tw-invert{syntax:"*";inherits:false}@property --tw-opacity{syntax:"*";inherits:false}@property --tw-saturate{syntax:"*";inherits:false}@property --tw-sepia{syntax:"*";inherits:false}@property --tw-drop-shadow{syntax:"*";inherits:false}@property --tw-drop-shadow-color{syntax:"*";inherits:false}@property --tw-drop-shadow-alpha{syntax:"<percentage>";inherits:false;initial-value:100%}@property --tw-drop-shadow-size{syntax:"*";inherits:false}
