:root {
  font-family: 'Pretendard', 'Apple SD Gothic Neo', 'Malgun Gothic', system-ui, sans-serif;
  color: #172337;
  background: #f6f7f9;
  font-synthesis: none;
  text-rendering: optimizeLegibility;
  --ink: #172337;
  --muted: #7f8a9a;
  --line: #e8ebf0;
  --paper: #f6f7f9;
  --white: #fff;
  --blue: #315efb;
  --blue-dark: #254de0;
  --navy: #172b47;
  --green: #2f9b74;
  --shadow: 0 12px 32px rgba(35, 48, 72, .055);
  --reading-min: 14px;
}

* { box-sizing: border-box; }

html { min-width: 320px; scroll-behavior: smooth; }

body { min-width: 320px; min-height: 100vh; margin: 0; background: var(--paper); }

button, input, textarea { font: inherit; }
button, a, summary, label { -webkit-tap-highlight-color: transparent; }
button { color: inherit; }
a { color: inherit; text-decoration: none; }
button:focus-visible, a:focus-visible, input:focus-visible, textarea:focus-visible, summary:focus-visible { outline: 3px solid rgba(49, 94, 251, .34); outline-offset: 3px; }
::selection { background: rgba(49, 94, 251, .17); }

.visually-hidden { position: absolute; width: 1px; height: 1px; padding: 0; margin: -1px; overflow: hidden; clip: rect(0, 0, 0, 0); white-space: nowrap; border: 0; }
.boot-screen { min-height: 100vh; display: grid; place-items: center; color: var(--muted); font-size: 14px; }

.app-shell { min-height: 100vh; display: grid; grid-template-columns: 244px minmax(0, 1fr); }
.sidebar { position: sticky; top: 0; display: flex; flex-direction: column; height: 100vh; padding: 28px 19px 20px; background: #fff; border-right: 1px solid #edf0f4; }
.brand { display: flex; align-items: center; gap: 10px; width: fit-content; margin: 0 0 47px 7px; }
.brand-mark { display: grid; width: 35px; height: 35px; place-items: center; border-radius: 12px; color: white; background: var(--blue); font: 600 12px 'DM Mono', monospace; letter-spacing: -1.3px; box-shadow: 0 5px 12px rgba(49, 94, 251, .22); }
.brand-name { color: #172337; font: 800 19px 'Pretendard', system-ui, sans-serif; letter-spacing: -.9px; }
.brand-name span { color: var(--blue); }
.sidebar-label { padding: 0 10px; color: #99a2af; font-size: 10px; font-weight: 700; letter-spacing: 1.4px; text-transform: uppercase; }
.primary-nav, .track-nav { display: grid; gap: 5px; margin-top: 12px; }
.nav-link { display: flex; min-height: 43px; align-items: center; gap: 12px; padding: 0 12px; border-radius: 11px; color: #6c788a; font-size: 13px; font-weight: 600; transition: background .18s ease, color .18s ease; }
.nav-link:hover, .track-nav-link:hover { color: var(--ink); background: #f5f7fb; }
.nav-link.is-active { color: var(--blue); background: #eef2ff; font-weight: 700; }
.nav-icon { display: grid; width: 18px; height: 20px; place-items: center; font-size: 18px; line-height: 1; }
.sidebar-divider { height: 1px; margin: 23px 6px 21px; background: #edf0f4; }
.sidebar-label-row { display: flex; align-items: center; justify-content: space-between; }
.sidebar-label-row a { color: #8d97a5; font-size: 10px; font-weight: 600; letter-spacing: 0; text-transform: none; }
.sidebar-label-row a:hover { color: var(--blue); }
.track-nav { margin-top: 10px; }
.track-nav-link { display: flex; min-height: 39px; align-items: center; gap: 10px; padding: 0 10px; border-radius: 10px; color: #657184; font-size: 12px; font-weight: 600; transition: background .18s ease; }
.mini-track-mark { display: grid; width: 24px; height: 24px; place-items: center; border-radius: 8px; font: 700 8px 'DM Mono', monospace; }
.sidebar-bottom { margin-top: auto; padding: 15px 14px 14px; border: 1px solid #e9edf4; border-radius: 15px; background: #f9fafc; }
.local-note-icon { display: grid; width: 25px; height: 25px; margin-bottom: 12px; place-items: center; border-radius: 8px; color: #457468; background: #e4f3ed; font-size: 15px; }
.sidebar-bottom strong { font-size: 11px; font-weight: 700; }
.sidebar-bottom p { margin: 5px 0 11px; color: #8791a0; font-size: 10px; line-height: 1.65; }
.text-link { display: inline-flex; align-items: center; gap: 6px; color: var(--blue); font-size: 11px; font-weight: 700; }
.text-link:hover, .subtle-link:hover { color: var(--blue-dark); }

.app-column { min-width: 0; }
.topbar { display: flex; min-height: 70px; align-items: center; justify-content: space-between; padding: 0 clamp(24px, 5vw, 62px); border-bottom: 1px solid #e9edf1; background: rgba(255, 255, 255, .72); }
.breadcrumbs { display: flex; align-items: center; gap: 10px; color: #96a0ad; font-size: 11px; }
.breadcrumbs strong { color: #566377; font-weight: 600; }
.breadcrumbs > span:nth-child(2) { color: #c1c7d0; }
.topbar-actions { display: flex; align-items: center; gap: 17px; }
.save-indicator { display: inline-flex; align-items: center; gap: 7px; color: #778396; font-size: 10px; font-weight: 600; }
.save-indicator i { width: 6px; height: 6px; border-radius: 50%; background: #54b68c; box-shadow: 0 0 0 3px #e9f7f0; }
.avatar-link { display: grid; width: 31px; height: 31px; place-items: center; border: 1px solid #dbe3f4; border-radius: 50%; color: #4d6598; background: #edf2ff; font-size: 10px; font-weight: 700; }
.page-content { width: min(1280px, 100%); min-height: calc(100vh - 132px); margin: 0 auto; padding: 40px clamp(24px, 5vw, 62px) 55px; }
.site-footer { display: flex; align-items: center; gap: 18px; padding: 18px clamp(24px, 5vw, 62px) 25px; color: #9aa3af; font-size: 12px; }
.site-footer span:first-child { color: #6e7a8d; font-weight: 700; }
.site-footer a:first-of-type { margin-left: auto; }
.site-footer a { color: #72819a; font-weight: 600; }
.site-footer a:hover { color: var(--blue); }
.mobile-nav { display: none; }

.welcome-row { display: grid; grid-template-columns: minmax(0, 1fr) 205px; align-items: center; gap: 34px; margin: 1px 0 31px; }
.eyebrow { margin: 0; color: #667085; font-size: 12px; font-weight: 650; letter-spacing: .4px; line-height: 1.5; }
.welcome-copy h1 { margin: 12px 0 11px; color: #182a43; font: 700 clamp(30px, 3.2vw, 42px)/1.22 'Pretendard', system-ui, sans-serif; letter-spacing: -1.8px; }
.welcome-copy h1 span { color: var(--blue); }
.welcome-description { margin: 0; color: #768295; font-size: 12px; line-height: 1.85; }
.welcome-summary { position: relative; min-height: 149px; overflow: hidden; padding: 17px 18px; border: 1px solid #e7ebf5; border-radius: 17px; background: #fff; box-shadow: 0 6px 18px rgba(42, 55, 82, .035); }
.summary-caption, .summary-foot { position: relative; z-index: 1; display: block; color: #7d899a; font-size: 10px; font-weight: 600; }
.welcome-summary strong { position: relative; z-index: 1; display: block; margin: 8px 0 1px; color: #20324f; font: 700 29px 'Pretendard', system-ui, sans-serif; letter-spacing: -1px; }
.welcome-summary strong small { color: #a0a9b8; font-size: 13px; font-weight: 600; }
.summary-foot { color: #99a2af; font-size: 9px; }

.dashboard-grid { display: grid; grid-template-columns: minmax(0, 1fr) 274px; align-items: start; gap: 25px; }
.dashboard-main-column, .dashboard-aside { display: grid; gap: 27px; min-width: 0; }
.resume-card { position: relative; display: flex; min-height: 222px; overflow: hidden; align-items: center; justify-content: space-between; padding: 27px 31px; border: 1px solid #dce5fb; border-radius: 18px; background: linear-gradient(110deg, #eaf0ff 0%, #f1f4ff 58%, #f2f5ff 100%); }
.resume-copy { position: relative; z-index: 2; max-width: 470px; }
.resume-kicker { display: flex; align-items: center; gap: 7px; color: #5168aa; font-size: 10px; font-weight: 700; }
.resume-track { margin: 19px 0 4px; color: #7887ac; font-size: 10px; font-weight: 600; }
.resume-track span { padding: 0 4px; color: #a9b4cc; }
.resume-copy h2 { margin: 0 0 7px; color: #253656; font: 700 24px 'Pretendard', system-ui, sans-serif; letter-spacing: -.8px; }
.resume-copy > p:last-of-type { max-width: 405px; margin: 0 0 18px; color: #6e7d9e; font-size: 11px; line-height: 1.65; }
.button { display: inline-flex; min-height: 40px; align-items: center; justify-content: center; gap: 12px; padding: 0 16px; border: 1px solid transparent; border-radius: 10px; cursor: pointer; font-size: 11px; font-weight: 700; text-align: center; transition: transform .15s ease, background .15s ease, border-color .15s ease, box-shadow .15s ease; }
.button:hover { transform: translateY(-1px); }
.button:disabled { cursor: progress; opacity: .7; transform: none; }
.button-primary { color: #fff; background: var(--blue); box-shadow: 0 5px 12px rgba(49, 94, 251, .16); }
.button-primary:hover { background: var(--blue-dark); box-shadow: 0 7px 17px rgba(49, 94, 251, .22); }
.button-secondary { color: #40547d; border-color: #e2e8f1; background: #fff; }
.button-secondary:hover { border-color: #ccd6eb; background: #f9faff; }
.button-outline { color: #5b6780; border-color: #e1e6ee; background: transparent; }
.button-small { min-height: 34px; padding: 0 12px; font-size: 10px; }
.button-full { display: flex; width: 100%; }

.content-section { min-width: 0; }
.section-heading { display: flex; align-items: end; justify-content: space-between; gap: 20px; margin-bottom: 14px; }
.section-heading h2 { margin: 5px 0 0; color: #24334b; font: 700 17px 'Pretendard', system-ui, sans-serif; letter-spacing: -.45px; }
.subtle-link { display: inline-flex; align-items: center; gap: 7px; padding: 4px 0; color: #556176; font-size: 10px; font-weight: 700; white-space: nowrap; }
.track-grid { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 13px; }
.track-card { display: flex; min-width: 0; flex-direction: column; min-height: 228px; padding: 15px 15px 14px; border: 1px solid #e7ebf1; border-radius: 15px; background: #fff; box-shadow: 0 4px 15px rgba(41, 55, 80, .025); transition: transform .16s ease, box-shadow .16s ease, border-color .16s ease; }
.track-card:hover { transform: translateY(-2px); border-color: #d7dfef; box-shadow: var(--shadow); }
.track-card-top { display: flex; align-items: center; justify-content: space-between; }
.track-mark { display: grid; width: 38px; height: 38px; place-items: center; border-radius: 12px; font: 700 11px 'DM Mono', monospace; letter-spacing: -.4px; }
.tone-yellow { color: #92611d; background: #fff0d0; }
.tone-blue { color: #405aa5; background: #e7edff; }
.tone-coral { color: #a94c3e; background: #ffe9e2; }
.tone-green { color: #317557; background: #e2f4e9; }
.tone-cyan { color: #337b84; background: #e0f4f5; }
.level-pill { padding: 5px 8px; border: 1px solid #edf0f4; border-radius: 20px; color: #8390a2; font-size: 9px; font-weight: 600; }
.track-card-copy { padding: 13px 0 8px; }
.track-card-copy .eyebrow { font-size: 12px; letter-spacing: .4px; }
.track-card-copy h3 { margin: 4px 0 5px; color: #263751; font: 700 15px 'Pretendard', system-ui, sans-serif; }
.track-card-copy > p:last-child { min-height: 34px; margin: 0; color: #8490a0; font-size: 10px; line-height: 1.65; }
.track-progress-row { display: flex; justify-content: space-between; margin-top: auto; padding: 9px 0 7px; color: #8490a0; font-size: 9px; }
.progress-track { height: 5px; overflow: hidden; border-radius: 8px; background: #eef1f5; }
.progress-track > span { display: block; height: 100%; border-radius: inherit; background: var(--progress-color, var(--blue)); transition: width .3s ease; }
.card-link { display: flex; align-items: center; justify-content: space-between; margin-top: 11px; padding-top: 10px; border-top: 1px solid #f0f2f5; color: #506589; font-size: 10px; font-weight: 700; }
.card-link span { color: #8695b1; font-size: 13px; transition: transform .15s ease; }
.card-link:hover { color: var(--blue); }
.card-link:hover span { transform: translateX(3px); }
.recent-section { margin-top: 1px; }
.recent-list { overflow: hidden; border: 1px solid #e8ebf0; border-radius: 14px; background: #fff; }
.recent-row { display: flex; min-height: 60px; align-items: center; gap: 12px; padding: 10px 14px; border-bottom: 1px solid #f0f2f5; transition: background .15s ease; }
.recent-row:last-child { border-bottom: 0; }
.recent-row:hover { background: #fafbfe; }
.recent-mark { width: 30px; height: 30px; border-radius: 10px; font-size: 8px; }
.recent-copy { display: grid; gap: 4px; min-width: 0; }
.recent-copy strong { overflow: hidden; color: #3a4960; font-size: 10px; font-weight: 700; text-overflow: ellipsis; white-space: nowrap; }
.recent-copy small { color: #929cac; font-size: 9px; }
.recent-result { display: inline-flex; align-items: center; gap: 6px; margin-left: auto; color: #8a96a7; font-size: 9px; font-weight: 700; white-space: nowrap; }
.recent-result.is-correct { color: #45a17c; }
.recent-result.is-review { color: #c3893f; }
.empty-card { display: flex; align-items: center; gap: 12px; padding: 15px 17px; border: 1px dashed #dbe1eb; border-radius: 14px; background: rgba(255, 255, 255, .56); }
.empty-card > div { min-width: 0; }
.empty-card strong { color: #43516a; font-size: 10px; }
.empty-card p { margin: 4px 0 0; color: #8b95a3; font-size: 9px; line-height: 1.6; }
.empty-card .button { margin-left: auto; white-space: nowrap; }
.empty-icon { display: grid; flex: 0 0 auto; width: 35px; height: 35px; place-items: center; border-radius: 12px; color: #647bce; background: #edf1ff; font-size: 17px; }

.dashboard-aside { gap: 13px; }
.aside-card { padding: 18px 17px; border: 1px solid #e8ebf1; border-radius: 15px; background: #fff; }
.aside-card-heading { display: flex; align-items: center; gap: 8px; }
.aside-card-heading .eyebrow { font-size: 12px; }
.aside-icon { display: grid; flex: 0 0 auto; width: 27px; height: 27px; place-items: center; border-radius: 9px; font-size: 13px; }
.icon-lilac { color: #6579d6; background: #edf0ff; }
.icon-mint { color: #39856a; background: #e5f5ee; }
.icon-peach { color: #bf775c; background: #fff0e8; }
.daily-card h2, .progress-card h2 { margin: 14px 0 5px; color: #293851; font: 700 15px Manrope, 'Pretendard', sans-serif; letter-spacing: -.3px; }
.daily-card > p, .progress-card > p { margin: 0; color: #8791a0; font-size: 10px; line-height: 1.65; }
.daily-question { display: flex; align-items: center; gap: 9px; margin: 15px 0 13px; padding: 10px; border: 1px solid #edf0f5; border-radius: 11px; background: #fbfcfe; }
.question-number { display: grid; width: 28px; height: 28px; flex: 0 0 auto; place-items: center; border-radius: 9px; color: #7c72be; background: #f0eeff; font: 600 9px 'DM Mono', monospace; }
.daily-question div { display: grid; gap: 4px; min-width: 0; }
.daily-question strong { overflow: hidden; color: #58657b; font-size: 9px; text-overflow: ellipsis; white-space: nowrap; }
.daily-question small { color: #9aa3af; font-size: 8px; }
.progress-card { padding-bottom: 17px; }
.progress-stat { display: flex; align-items: baseline; justify-content: space-between; gap: 7px; margin-top: 15px; padding-top: 11px; border-top: 1px solid #f0f2f6; color: #818d9f; font-size: 9px; }
.progress-stat strong { color: #354661; font-size: 10px; text-align: right; }
.progress-stat strong small { color: #9ba5b2; font-size: 9px; font-weight: 500; }
.progress-card .text-link { margin-top: 14px; font-size: 9px; }
.privacy-note { display: flex; align-items: flex-start; gap: 9px; padding: 6px 4px; color: #70867d; }
.privacy-note > span { padding-top: 1px; color: #80b39c; font-size: 14px; }
.privacy-note p { margin: 0; color: #8b96a2; font-size: 9px; line-height: 1.6; }
.privacy-note strong { color: #637c70; font-size: 9px; }

.page-heading { margin: 7px 0 28px; }
.page-heading h1 { margin: 9px 0 7px; color: #1c2d46; font: 700 clamp(28px, 3vw, 38px)/1.25 'Pretendard', system-ui, sans-serif; letter-spacing: -1.3px; }
.page-heading > p:last-child { margin: 0; color: #7b8797; font-size: 12px; line-height: 1.75; }
.page-content > .content-section + .content-section { margin-top: 35px; }
.compact-heading { margin-bottom: 13px; }
.track-grid:not(.track-grid-featured) { grid-template-columns: repeat(3, minmax(0, 1fr)); }

.back-link { display: inline-flex; align-items: center; gap: 8px; margin: 0 0 22px; color: #7d899b; font-size: 10px; font-weight: 600; }
.back-link:hover { color: var(--blue); }
.track-hero { position: relative; display: flex; min-height: 226px; overflow: hidden; align-items: center; justify-content: space-between; padding: 28px 32px; border: 1px solid #e5eaf4; border-radius: 19px; }
.tone-panel-yellow { background: linear-gradient(115deg, #fff9e9, #fffdf6); }
.tone-panel-blue { background: linear-gradient(115deg, #eef2ff, #f8f9ff); }
.tone-panel-coral { background: linear-gradient(115deg, #fff0eb, #fffaf8); }
.tone-panel-green { background: linear-gradient(115deg, #edf8f1, #f8fcf8); }
.tone-panel-cyan { background: linear-gradient(115deg, #eaf8f8, #f7fcfc); }
.track-hero-copy { position: relative; z-index: 2; max-width: 550px; }
.track-hero h1 { margin: 8px 0 6px; color: #21334f; font: 700 34px 'Pretendard', system-ui, sans-serif; letter-spacing: -1.3px; }
.track-hero-copy > p:not(.eyebrow) { margin: 0; color: #738094; font-size: 11px; }
.track-hero-meta { display: flex; align-items: center; gap: 11px; margin-top: 19px; color: #7d8898; font-size: 9px; font-weight: 600; }
.meta-divider { width: 3px; height: 3px; border-radius: 50%; background: #acb5c1; }
.track-hero-progress { position: relative; z-index: 2; width: 190px; padding: 15px 16px; border: 1px solid rgba(255, 255, 255, .85); border-radius: 13px; background: rgba(255, 255, 255, .73); }
.track-hero-progress > span { color: #8390a0; font-size: 9px; font-weight: 600; }
.track-hero-progress strong { float: right; color: #435679; font-size: 12px; }
.track-hero-progress .progress-track { clear: both; margin-top: 11px; }
.track-overview { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 12px; margin-top: 13px; }
.track-overview p { display: grid; gap: 5px; margin: 0; padding: 13px 15px; border: 1px solid #e7ebf1; border-radius: 12px; color: #66748a; background: #fff; }
.track-overview strong { color: #35455f; font-size: 14px; }
.lesson-list-section { margin-top: 30px; }
.muted-label { color: #9aa3b0; font-size: 9px; }
.lesson-list { overflow: hidden; border: 1px solid #e7ebf1; border-radius: 15px; background: #fff; }
.topic-hero { min-height: 190px; }
.lesson-row { display: flex; min-height: 77px; align-items: center; gap: 14px; padding: 13px 18px; border-bottom: 1px solid #f0f2f5; transition: background .14s ease; }
.lesson-row:last-child { border-bottom: 0; }
.lesson-row:hover { background: #fafbfe; }
.lesson-index { display: grid; width: 32px; height: 32px; flex: 0 0 auto; place-items: center; border: 1px solid #e8ebf1; border-radius: 11px; color: #7e8a9b; background: #f8f9fb; font: 600 10px 'DM Mono', monospace; }
.lesson-index.is-done { color: #318767; border-color: #d9f0e4; background: #eaf8f0; font-family: inherit; font-size: 13px; }
.lesson-row-copy { display: grid; gap: 5px; min-width: 0; }
.lesson-row-title { color: #35445c; font-size: 11px; font-weight: 700; }
.lesson-row-subtitle { overflow: hidden; color: #8d97a5; font-size: 9px; text-overflow: ellipsis; white-space: nowrap; }
.lesson-row-meta { margin-left: auto; color: #99a3b1; font-size: 9px; white-space: nowrap; }
.lesson-row-meta i { padding: 0 3px; color: #c4cad2; font-style: normal; }
.row-arrow { color: #9da8b6; font-size: 14px; }

.lesson-layout { display: grid; grid-template-columns: minmax(0, 1fr) 252px; align-items: start; gap: 36px; }
.lesson-article { min-width: 0; max-width: 760px; }
.eyebrow-separator { padding: 0 5px; color: #c2c9d3; }
.lesson-article > h1 { margin: 10px 0 8px; color: #1d304a; font: 700 clamp(29px, 3.5vw, 40px)/1.2 'Pretendard', system-ui, sans-serif; letter-spacing: -1.4px; }
.lesson-lead { margin: 0; color: #718096; font-size: 13px; line-height: 1.7; }
.lesson-meta-row { display: flex; flex-wrap: wrap; align-items: center; gap: 10px; margin: 18px 0 25px; color: #929caa; font-size: 9px; }
.completed-pill { padding: 4px 8px; border-radius: 15px; color: #358466; background: #e8f6ee; font-weight: 700; }
.lesson-body-copy { padding: 21px 23px; border: 1px solid #e7ebf1; border-radius: 15px; background: #fff; }
.lesson-body-copy > p { margin: 0 0 23px; color: #566478; font-size: 12px; line-height: 1.9; }
.lesson-body-copy h2 { margin: 22px 0 12px; color: #2d3c54; font: 700 15px Manrope, 'Pretendard', sans-serif; letter-spacing: -.3px; }
.learning-points { display: grid; gap: 11px; margin: 0; padding: 0; list-style: none; }
.learning-points li { display: flex; align-items: flex-start; gap: 9px; color: #647186; font-size: 11px; line-height: 1.75; }
.point-check { display: grid; flex: 0 0 auto; width: 17px; height: 17px; margin-top: 1px; place-items: center; border-radius: 6px; color: #42896f; background: #e7f5ee; font-size: 9px; font-weight: 700; }
.lesson-body-copy code:not(pre code) { padding: 2px 5px; border-radius: 5px; color: #485a8a; background: #f0f3fa; font: 500 10px 'DM Mono', monospace; }
.code-block { overflow: hidden; border-radius: 12px; background: #182438; }
.code-block-bar { display: flex; min-height: 36px; align-items: center; gap: 9px; padding: 0 13px; border-bottom: 1px solid rgba(255, 255, 255, .07); color: #8593a8; font: 9px 'DM Mono', monospace; }
.code-dots { display: inline-flex; gap: 4px; }
.code-dots i { width: 6px; height: 6px; border-radius: 50%; background: #e78f80; }
.code-dots i:nth-child(2) { background: #e4bc65; }
.code-dots i:nth-child(3) { background: #6fb995; }
.copy-code-button { margin-left: auto; padding: 3px 7px; border: 0; border-radius: 5px; color: #d0d8e4; background: #39465a; cursor: pointer; font-size: 8px; }
.copy-code-button:hover { color: #fff; background: #4d5c72; }
.code-block pre { overflow: auto; margin: 0; padding: 16px; color: #d9e1f0; font: 11px/1.8 'DM Mono', Consolas, monospace; tab-size: 4; }
.lesson-tip { display: flex; align-items: flex-start; gap: 10px; margin-top: 15px; padding: 13px 15px; border: 1px solid #e5eaf8; border-radius: 12px; background: #f7f8fe; }
.tip-mark { display: grid; flex: 0 0 auto; width: 19px; height: 19px; place-items: center; border-radius: 50%; color: #5e74be; background: #e8edff; font: 700 10px Georgia, serif; }
.lesson-tip strong { color: #596985; font-size: 10px; }
.lesson-tip p { margin: 4px 0 0; color: #8591a3; font-size: 9px; line-height: 1.7; }
.lesson-navigation { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 12px; margin-top: 18px; }
.lesson-navigation a, .lesson-nav-empty { display: flex; min-height: 68px; flex-direction: column; justify-content: center; gap: 6px; padding: 12px 15px; border: 1px solid #e5eaf1; border-radius: 12px; color: #596a85; background: #fff; }
.lesson-navigation a:hover { border-color: #cfd9ef; background: #fafbff; }
.lesson-navigation span { color: #8b96a7; }
.lesson-navigation strong { color: #41536f; font-size: 14px; }
.lesson-nav-next { align-items: flex-end; text-align: right; }
.lesson-nav-empty { color: #abb3bf; background: #f9fafb; }
.content-source { display: grid; gap: 12px; margin-top: 20px; padding: 16px; border: 1px solid #e5eaf2; border-radius: 13px; background: #fff; }
.content-source h2 { margin: 3px 0 5px; color: #394a63; font-size: 15px; }
.content-source p { margin: 0; color: #728096; font-size: 12px; line-height: 1.7; }
.content-source ul { display: grid; gap: 7px; margin: 0; padding: 0; list-style: none; }
.content-source a { display: inline-flex; align-items: center; gap: 5px; color: #5269a7; text-decoration: underline; text-underline-offset: 3px; }
.lesson-action-card { position: sticky; top: 22px; padding: 19px 17px 16px; border: 1px solid #e5eaf4; border-radius: 16px; background: #fff; box-shadow: 0 7px 22px rgba(40, 55, 80, .04); }
.lesson-action-top { display: flex; align-items: center; gap: 8px; }
.lesson-action-top .eyebrow { font-size: 12px; }
.lesson-action-card h2 { margin: 15px 0 7px; color: #2c3b54; font: 700 19px/1.4 'Pretendard', system-ui, sans-serif; letter-spacing: -.5px; }
.lesson-action-card > p { margin: 0; color: #8791a0; font-size: 10px; }
.lesson-action-details { display: grid; gap: 10px; margin: 18px 0; padding: 14px 0; border-top: 1px solid #f0f2f5; border-bottom: 1px solid #f0f2f5; }
.lesson-action-details span { display: flex; align-items: center; gap: 8px; color: #738094; font-size: 9px; }
.lesson-action-details i { display: grid; width: 15px; height: 15px; place-items: center; border-radius: 50%; color: #429575; background: #e7f5ee; font-size: 8px; font-style: normal; font-weight: 700; }
.centered-link { display: flex; justify-content: center; margin-top: 12px; }
.saved-small { margin-top: 12px; color: #98a2af; font-size: 8px; text-align: center; }
.saved-small span { margin-right: 4px; color: #74aa90; }

.exercise-layout { display: grid; grid-template-columns: minmax(0, 1fr) 260px; align-items: start; gap: 28px; }
.exercise-main { min-width: 0; }
.exercise-heading { display: flex; align-items: end; justify-content: space-between; gap: 18px; margin-bottom: 17px; }
.exercise-heading h1 { margin: 7px 0 0; color: #1d304a; font: 700 clamp(25px, 2.8vw, 33px)/1.22 'Pretendard', system-ui, sans-serif; letter-spacing: -1.1px; }
.question-type-pill { flex: 0 0 auto; padding: 6px 9px; border: 1px solid #e5eaf3; border-radius: 18px; color: #6d7da0; background: #fff; font-size: 9px; font-weight: 700; }
.exercise-card { padding: 19px 21px 16px; border: 1px solid #e5e9f0; border-radius: 16px; background: #fff; box-shadow: 0 6px 21px rgba(40, 55, 80, .035); }
.exercise-card-top { display: flex; align-items: center; justify-content: space-between; padding-bottom: 13px; border-bottom: 1px solid #f0f2f5; }
.exercise-step { color: #909bab; font-size: 9px; }
.exercise-step strong { margin-left: 4px; color: #586887; font: 600 10px 'DM Mono', monospace; }
.exercise-progress-label { color: #9aa3af; font-size: 8px; }
.exercise-prompt { margin: 18px 0; color: #45546b; font-size: 12px; font-weight: 600; line-height: 1.8; }
.exercise-prompt code { padding: 2px 5px; border-radius: 5px; color: #475b91; background: #f0f3fa; font: 500 10px 'DM Mono', monospace; }
.answer-fieldset { min-width: 0; margin: 0; padding: 0; border: 0; }
.choice-list { display: grid; gap: 9px; }
.choice-option { position: relative; display: flex; min-height: 48px; align-items: center; gap: 11px; padding: 9px 12px; border: 1px solid #e7ebf1; border-radius: 11px; background: #fff; cursor: pointer; transition: border-color .15s ease, background .15s ease; }
.choice-option:hover { border-color: #cad5f1; background: #fafbff; }
.choice-option:has(input:checked) { border-color: #8da4ff; background: #f6f8ff; box-shadow: 0 0 0 2px rgba(77, 111, 245, .08); }
.choice-option input { position: absolute; width: 1px; height: 1px; opacity: 0; }
.choice-option:has(input:focus-visible) { outline: 3px solid rgba(49, 94, 251, .34); outline-offset: 3px; }
.choice-letter { display: grid; width: 25px; height: 25px; flex: 0 0 auto; place-items: center; border: 1px solid #e7ebf1; border-radius: 8px; color: #556176; background: #fafbfc; font: 600 9px 'DM Mono', monospace; }
.choice-option:has(input:checked) .choice-letter { color: #fff; border-color: var(--blue); background: var(--blue); }
.choice-text { color: #657286; font-size: 10px; line-height: 1.6; }
.choice-text code { color: #52689d; font: 500 9px 'DM Mono', monospace; }
.choice-check { display: none; margin-left: auto; color: var(--blue); font-size: 11px; font-weight: 700; }
.choice-option:has(input:checked) .choice-check { display: block; }
.field-label { display: block; margin: 0 0 8px; color: #68758a; font-size: 10px; font-weight: 700; }
.answer-textarea, .code-editor { display: block; width: 100%; resize: vertical; border: 1px solid #e1e6ef; border-radius: 11px; color: #334258; background: #fbfcfe; font-size: 11px; line-height: 1.75; transition: border-color .15s ease, box-shadow .15s ease; }
.answer-textarea { min-height: 80px; padding: 12px 13px; }
.answer-textarea::placeholder { color: #abb3bf; }
.answer-textarea:focus, .code-editor:focus { border-color: #93a8ff; outline: 0; box-shadow: 0 0 0 3px rgba(49, 94, 251, .09); }
.field-hint { margin: 6px 0 0; color: #97a0ad; font-size: 8px; line-height: 1.6; }
.line-code { display: grid; overflow: hidden; border: 1px solid #e5e9f0; border-radius: 11px; background: #182438; }
.code-line { display: flex; min-height: 37px; align-items: center; gap: 12px; padding: 0 12px; border: 0; border-bottom: 1px solid rgba(255,255,255,.055); color: #d2dbea; background: transparent; cursor: pointer; text-align: left; }
.code-line:last-child { border-bottom: 0; }
.code-line:hover { background: rgba(255,255,255,.045); }
.code-line.is-selected { background: rgba(104, 130, 255, .24); box-shadow: inset 3px 0 #83a0ff; }
.line-number { display: grid; width: 20px; flex: 0 0 auto; place-items: center; color: #a6b2c2; font: 9px 'DM Mono', monospace; }
.code-line.is-selected .line-number { color: #bccaff; }
.code-line code { overflow: auto; color: #d7e0ef; font: 10px 'DM Mono', Consolas, monospace; white-space: pre; }
.editor-heading { display: flex; align-items: center; justify-content: space-between; }
.editor-language { display: inline-flex; align-items: center; gap: 6px; color: #8794a6; font-size: 8px; }
.editor-language i { width: 6px; height: 6px; border-radius: 50%; background: #e2b254; }
.code-editor { min-height: 148px; padding: 13px 14px; border-color: #25344c; border-radius: 11px; color: #dbe4f1; background: #182438; font: 10px/1.8 'DM Mono', Consolas, monospace; tab-size: 2; }
.answer-actions { display: flex; flex-wrap: wrap; align-items: center; gap: 12px; margin-top: 17px; padding-top: 14px; border-top: 1px solid #f0f2f5; }
.answer-actions .button { min-height: 38px; }
.runner-status { flex-basis: 100%; min-height: 1.2em; color: var(--text-muted); font-size: 0.875rem; }
.answer-save-hint { color: #9ba4b0; font-size: 8px; }
.coding-requirements { display: flex; gap: 8px; margin: -5px 0 16px; padding: 10px 11px; border: 1px solid #e8edf9; border-radius: 9px; color: #75829b; background: #f8f9fe; font-size: 9px; line-height: 1.6; }
.requirements-icon { color: #7488d3; font-size: 13px; }
.answer-feedback { display: flex; align-items: flex-start; gap: 9px; margin-top: 14px; padding: 11px 12px; border: 1px solid transparent; border-radius: 10px; }
.feedback-correct { border-color: #d9efe3; background: #eff9f3; }
.feedback-review { border-color: #f0e5cb; background: #fffaf0; }
.feedback-icon { display: grid; flex: 0 0 auto; width: 19px; height: 19px; place-items: center; border-radius: 50%; color: #318665; background: #dcf2e5; font-size: 10px; font-weight: 700; }
.feedback-review .feedback-icon { color: #a47934; background: #f8edcf; }
.answer-feedback strong { color: #47705f; font-size: 9px; }
.feedback-review strong { color: #846a3a; }
.answer-feedback p { margin: 4px 0 0; color: #78877f; font-size: 8px; line-height: 1.6; }
.feedback-review p { color: #8d8064; }
.hint-disclosure { margin-top: 15px; padding-top: 12px; border-top: 1px solid #f0f2f5; }
.hint-disclosure summary { display: flex; width: fit-content; align-items: center; gap: 7px; color: #7b86a3; cursor: pointer; font-size: 9px; font-weight: 600; list-style: none; }
.hint-disclosure summary::-webkit-details-marker { display: none; }
.hint-light { color: #a494d9; }
.hint-disclosure > p { margin: 8px 0 0 19px; color: #7f8ba0; font-size: 9px; line-height: 1.7; }
.solution-disclosure { margin-top: 14px; padding-top: 12px; border-top: 1px solid #f0f2f5; }
.solution-disclosure summary { width: fit-content; color: #697a9b; cursor: pointer; font-weight: 700; list-style: none; }
.solution-disclosure summary::-webkit-details-marker { display: none; }
.solution-disclosure[open] summary { margin-bottom: 10px; }
.solution-card { padding: 16px 18px; border: 1px solid #e7ebf1; border-radius: 14px; background: #fff; }
.solution-heading { display: flex; align-items: center; gap: 9px; }
.solution-mark { display: grid; width: 27px; height: 27px; place-items: center; border-radius: 9px; color: #6878c2; background: #eff1ff; font-size: 15px; }
.solution-heading .eyebrow { font-size: 12px; }
.solution-heading h2 { margin: 2px 0 0; color: #44536a; font: 700 12px Manrope, 'Pretendard', sans-serif; }
.solution-card > p { margin: 12px 0 0; color: #738094; font-size: 10px; line-height: 1.8; }
.solution-card code { padding: 2px 5px; border-radius: 5px; color: #52689d; background: #f0f3fa; font: 500 9px 'DM Mono', monospace; }
.exercise-bottom-actions { display: flex; align-items: center; justify-content: space-between; gap: 15px; margin-top: 17px; }
.exercise-bottom-actions .button { min-height: 35px; }
.exercise-side { display: grid; gap: 12px; padding-top: 57px; }
.side-goal-card { padding: 17px 15px; border: 1px solid #e6eaf1; border-radius: 14px; background: #fff; }
.side-goal-card .eyebrow { margin-top: 12px; font-size: 12px; }
.side-goal-card h2 { margin: 7px 0 0; color: #4b5a72; font-size: 12px; line-height: 1.75; }
.goal-divider { height: 1px; margin: 15px 0 11px; background: #eff1f5; }
.side-goal-card .muted-label { font-size: 8px; }
.side-goal-card > a { display: flex; align-items: center; justify-content: space-between; margin-top: 7px; color: #6a7892; font-size: 9px; font-weight: 600; }
.side-privacy-note { display: flex; gap: 8px; padding: 10px; border-radius: 10px; color: #69947f; background: #eff8f3; }
.side-privacy-note > span { font-size: 12px; }
.side-privacy-note p { margin: 0; color: #7b9185; font-size: 8px; line-height: 1.65; }
.side-privacy-note strong { color: #5f806e; }
.runner-frame { position: fixed; left: -10px; bottom: -10px; width: 1px; height: 1px; border: 0; opacity: 0; pointer-events: none; }

.profile-heading { margin-bottom: 23px; }
.profile-stats-grid { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 13px; }
.profile-stat-card { display: grid; min-height: 139px; grid-template-columns: 32px 1fr; align-content: start; align-items: center; gap: 8px 10px; padding: 17px; border: 1px solid #e7ebf1; border-radius: 14px; background: #fff; }
.stat-icon { display: grid; width: 30px; height: 30px; grid-row: span 2; place-items: center; border-radius: 10px; font-size: 13px; }
.stat-caption { align-self: end; color: #8c97a6; font-size: 9px; }
.profile-stat-card > strong { color: #354661; font: 700 22px 'Pretendard', system-ui, sans-serif; letter-spacing: -.7px; }
.profile-stat-card > strong small { color: #9ca5b2; font: 600 10px 'DM Sans', sans-serif; }
.stat-foot { grid-column: 2; color: #a1aab6; font-size: 8px; }
.profile-layout { display: grid; grid-template-columns: minmax(0, 1fr) 280px; align-items: start; gap: 15px; margin-top: 21px; }
.profile-panel { min-width: 0; padding: 17px; border: 1px solid #e7ebf1; border-radius: 15px; background: #fff; }
.profile-panel .section-heading { margin-bottom: 12px; }
.profile-panel .section-heading h2 { font-size: 14px; }
.profile-panel .recent-list { border-radius: 11px; }
.profile-panel .recent-row { min-height: 54px; padding: 8px 10px; }
.empty-state { display: grid; justify-items: center; padding: 28px 12px; text-align: center; }
.empty-state .empty-icon { width: 43px; height: 43px; margin-bottom: 12px; font-size: 18px; }
.empty-state strong, .empty-state h1 { margin: 0; color: #44536a; font-size: 12px; font-weight: 700; }
.empty-state p { margin: 6px 0 13px; color: #8d97a5; font-size: 9px; line-height: 1.7; }
.backup-panel { padding: 18px; background: linear-gradient(150deg, #fff 15%, #f7f8ff); }
.backup-emblem { display: grid; width: 38px; height: 38px; margin-bottom: 17px; place-items: center; border: 1px solid #e2e8ff; border-radius: 13px; color: #657de1; background: #edf1ff; font-size: 18px; }
.backup-panel .eyebrow { font-size: 12px; }
.backup-panel h2 { margin: 7px 0; color: #34445d; font: 700 17px/1.45 'Pretendard', system-ui, sans-serif; letter-spacing: -.45px; }
.backup-panel > p:not(.eyebrow):not(.backup-caption) { margin: 0 0 14px; color: #818c9d; font-size: 9px; line-height: 1.75; }
.import-button { position: relative; margin-top: 8px; cursor: pointer; }
.import-button input { position: absolute; width: 1px; height: 1px; overflow: hidden; clip: rect(0,0,0,0); }
.import-button:focus-within { outline: 3px solid rgba(49, 94, 251, .34); outline-offset: 3px; }
.backup-caption { margin: 10px 0 0; color: #a0a8b4; font-size: 8px; line-height: 1.5; }
.storage-info { display: flex; align-items: flex-start; gap: 10px; margin-top: 15px; padding: 13px 14px; border: 1px solid #e8edf1; border-radius: 12px; background: rgba(255,255,255,.75); }
.storage-info-icon { color: #5c9b7e; font-size: 14px; }
.storage-info strong { color: #667487; font-size: 9px; }
.storage-info p { margin: 4px 0 0; color: #929ba7; font-size: 8px; line-height: 1.7; }
.text-button { margin-left: auto; padding: 4px 0 4px 9px; border: 0; background: transparent; cursor: pointer; font-size: 8px; font-weight: 700; }
.danger-text { color: #bf7070; }
.danger-text:hover { color: #9e4d4d; }
.page-empty { min-height: 52vh; align-content: center; }
.page-empty h1 { font-size: 20px; }
.page-empty .button { margin-top: 6px; }

.toast-region { position: fixed; z-index: 100; top: 20px; right: 22px; display: grid; gap: 8px; pointer-events: none; }
.toast { display: flex; max-width: min(390px, calc(100vw - 32px)); align-items: center; gap: 9px; padding: 12px 15px; border: 1px solid #dde7e2; border-radius: 12px; color: #4a6759; background: #fff; box-shadow: 0 10px 30px rgba(38, 56, 72, .13); font-size: 10px; line-height: 1.55; animation: toast-in .2s ease-out; }
.toast > span { display: grid; width: 19px; height: 19px; flex: 0 0 auto; place-items: center; border-radius: 50%; color: #328664; background: #e8f6ee; font-weight: 700; }
.toast-error { color: #835a56; border-color: #f2dedb; }
.toast-error > span { color: #a7564c; background: #fff0ee; }
@keyframes toast-in { from { opacity: 0; transform: translateY(-5px); } to { opacity: 1; transform: translateY(0); } }

@media (max-width: 1180px) {
  .app-shell { grid-template-columns: 218px minmax(0, 1fr); }
  .sidebar { padding-inline: 15px; }
  .dashboard-grid { grid-template-columns: minmax(0, 1fr) 250px; gap: 18px; }
  .track-grid { gap: 10px; }
  .track-card { padding-inline: 12px; }
}

@media (max-width: 980px) {
  .app-shell { grid-template-columns: 195px minmax(0, 1fr); }
  .sidebar { padding-inline: 12px; }
  .dashboard-grid { grid-template-columns: minmax(0, 1fr); }
  .dashboard-aside { grid-template-columns: repeat(2, minmax(0, 1fr)); align-items: start; }
  .privacy-note { grid-column: 1 / -1; }
  .track-grid, .track-grid:not(.track-grid-featured) { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}

@media (max-width: 760px) {
  .app-shell { display: block; padding-bottom: 67px; }
  .sidebar { display: none; }
  .topbar { min-height: 60px; padding-inline: 18px; }
  .breadcrumbs { gap: 7px; font-size: 10px; }
  .topbar-actions { gap: 11px; }
  .save-indicator { font-size: 0; }
  .save-indicator i { width: 7px; height: 7px; }
  .avatar-link { width: 29px; height: 29px; }
  .page-content { min-height: calc(100vh - 124px); padding: 29px 18px 32px; }
  .site-footer { gap: 12px; padding: 14px 18px 18px; font-size: 11px; }
  .site-footer span:nth-child(2) { display: none; }
  .mobile-nav { position: fixed; z-index: 40; right: 0; bottom: 0; left: 0; display: grid; grid-template-columns: repeat(3, 1fr); padding: 8px 10px max(8px, env(safe-area-inset-bottom)); border-top: 1px solid #e9edf2; background: rgba(255,255,255,.96); backdrop-filter: blur(14px); }
  .mobile-nav .nav-link { min-height: 48px; flex-direction: column; justify-content: center; gap: 3px; padding: 4px; border-radius: 9px; font-size: 14px; }
  .mobile-nav .nav-icon { height: 18px; font-size: 17px; }
  .welcome-row { grid-template-columns: minmax(0, 1fr) 115px; gap: 9px; margin-bottom: 21px; }
  .welcome-copy h1 { margin-top: 9px; font-size: clamp(27px, 7vw, 34px); letter-spacing: -1.3px; }
  .welcome-description { font-size: 10px; }
  .desktop-break { display: none; }
  .welcome-summary { min-height: 126px; padding: 13px 12px; }
  .summary-caption { font-size: 8px; }
  .welcome-summary strong { margin-top: 25px; font-size: 24px; }
  .summary-foot { font-size: 8px; }
  .resume-card { min-height: 205px; padding: 21px 19px; }
  .resume-copy h2 { font-size: 21px; }
  .dashboard-main-column, .dashboard-aside { gap: 23px; }
  .dashboard-aside { grid-template-columns: minmax(0, 1fr); gap: 11px; }
  .privacy-note { grid-column: auto; }
  .section-heading h2 { font-size: 15px; }
  .track-grid, .track-grid:not(.track-grid-featured) { grid-template-columns: minmax(0, 1fr); }
  .track-card { min-height: auto; padding: 13px 14px; }
  .track-card-copy { padding: 10px 0 5px; }
  .track-card-copy > p:last-child { min-height: auto; }
  .track-progress-row { margin-top: 8px; }
  .empty-card { flex-wrap: wrap; }
  .empty-card .button { margin-left: auto; }
  .track-hero { min-height: 200px; padding: 23px 20px; }
  .track-hero h1 { font-size: 29px; }
  .track-hero-progress { position: absolute; right: 19px; bottom: 17px; left: 19px; width: auto; padding: 9px 11px; }
  .track-hero-progress .progress-track { margin-top: 7px; }
  .track-overview { grid-template-columns: minmax(0, 1fr); gap: 8px; }
  .lesson-list-section { margin-top: 24px; }
  .lesson-row { min-height: 70px; gap: 9px; padding: 11px 10px; }
  .lesson-index { width: 28px; height: 28px; border-radius: 9px; }
  .lesson-row-subtitle { max-width: 46vw; }
  .lesson-row-meta { display: none; }
  .lesson-layout, .exercise-layout, .profile-layout { grid-template-columns: minmax(0, 1fr); gap: 16px; }
  .lesson-action-card { position: static; order: -1; }
  .lesson-action-card h2 br { display: none; }
  .lesson-action-card h2 { font-size: 16px; }
  .lesson-action-details { grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 5px; }
  .lesson-action-details span { align-items: flex-start; font-size: 8px; line-height: 1.5; }
  .lesson-action-details i { flex: 0 0 auto; }
  .lesson-body-copy { padding: 18px 16px; }
  .exercise-side { grid-row: 1; padding-top: 0; }
  .side-goal-card { padding: 13px; }
  .side-goal-card h2 { font-size: 10px; }
  .side-goal-card .goal-divider, .side-goal-card .muted-label, .side-goal-card > a { display: none; }
  .side-privacy-note { display: none; }
  .exercise-heading { align-items: center; }
  .exercise-heading h1 { font-size: 24px; }
  .question-type-pill { font-size: 8px; }
  .exercise-card { padding: 15px 13px 13px; }
  .exercise-prompt { font-size: 11px; }
  .exercise-progress-label { max-width: 48%; text-align: right; }
  .choice-option { gap: 8px; padding-inline: 9px; }
  .choice-text { font-size: 9px; }
  .answer-actions { align-items: flex-start; }
  .answer-save-hint { align-self: center; }
  .profile-stats-grid { grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 7px; }
  .profile-stat-card { min-height: 125px; grid-template-columns: 25px 1fr; gap: 6px; padding: 11px 9px; }
  .stat-icon { width: 24px; height: 24px; border-radius: 8px; font-size: 10px; }
  .stat-caption { font-size: 8px; line-height: 1.4; }
  .profile-stat-card > strong { font-size: 18px; }
  .stat-foot { font-size: 7px; line-height: 1.5; }
  .profile-panel { padding: 13px 11px; }
  .storage-info { flex-wrap: wrap; }
  .storage-info > div { flex: 1; min-width: 220px; }
  .text-button { width: 100%; margin: 3px 0 0; padding: 6px 0 0; text-align: left; }
  .toast-region { top: auto; right: 12px; bottom: 78px; left: 12px; }
  .toast { max-width: none; }
}

@media (max-width: 390px) {
  .welcome-row { grid-template-columns: minmax(0, 1fr) 94px; }
  .welcome-copy h1 { font-size: 27px; }
  .welcome-summary { padding-inline: 9px; }
  .welcome-summary strong { font-size: 21px; }
  .resume-copy > p:last-of-type { max-width: 245px; }
  .profile-stat-card { grid-template-columns: 1fr; }
  .stat-icon { grid-row: auto; }
  .stat-foot { grid-column: 1; }
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { scroll-behavior: auto !important; animation-duration: .01ms !important; animation-iteration-count: 1 !important; transition-duration: .01ms !important; }
}

.page-content :is(
  p:not(.eyebrow), a, button, label, summary,
  .lesson-row-title, .lesson-row-subtitle, .lesson-row-meta,
  .track-progress-row, .track-hero-meta, .lesson-meta-row,
  .choice-text, .field-label, .field-hint, .answer-save-hint,
  .answer-textarea, .code-editor,
  .coding-requirements, .answer-feedback strong,
  .side-goal-card h2, .stat-caption, .stat-foot
) { font-size: max(var(--reading-min), 1em); }

:root {
  --text-muted: #556176;
  --text-success: #286b4e;
  --text-review: #725015;
  --text-danger: #93413a;
}

.sidebar-label, .sidebar-label-row a, .breadcrumbs, .save-indicator,
.sidebar-bottom p, .site-footer, .site-footer a {
  color: var(--text-muted);
}

.page-content :is(
  p:not(.eyebrow), .eyebrow, .summary-caption, .summary-foot,
  .welcome-summary strong small, .resume-track, .level-pill,
  .track-card-copy > p:last-child, .track-progress-row, .recent-copy small,
  .recent-result, .daily-card > p, .progress-card > p, .daily-question small,
  .progress-stat, .progress-stat strong small, .question-number,
  .page-heading > p:last-child, .back-link, .track-hero-copy > p:not(.eyebrow),
  .track-hero-meta, .track-hero-progress > span, .muted-label, .lesson-index,
  .lesson-row-subtitle, .lesson-row-meta, .lesson-meta-row, .lesson-lead,
  .lesson-body-copy > p, .learning-points li, .lesson-tip p,
  .lesson-navigation span, .lesson-nav-empty, .content-source p,
  .lesson-action-card > p, .lesson-action-details span, .saved-small,
  .question-type-pill, .exercise-step, .exercise-progress-label,
  .exercise-prompt, .choice-text, .field-label, .field-hint,
  .answer-save-hint, .coding-requirements, .hint-disclosure summary,
  .hint-disclosure > p, .solution-disclosure summary, .solution-heading h2,
  .solution-card > p, .side-goal-card h2, .side-goal-card > a,
  .side-privacy-note p, .stat-caption, .profile-stat-card > strong small,
  .stat-foot, .empty-state strong, .empty-state p,
  .backup-panel > p:not(.eyebrow):not(.backup-caption), .backup-caption,
  .storage-info strong, .storage-info p
) {
  color: var(--text-muted);
}

.page-content .completed-pill, .page-content .recent-result.is-correct,
.page-content .answer-feedback.feedback-correct strong,
.page-content .answer-feedback.feedback-correct p,
.page-content .side-privacy-note strong {
  color: var(--text-success);
}

.page-content .recent-result.is-review,
.page-content .answer-feedback.feedback-review strong,
.page-content .answer-feedback.feedback-review p {
  color: var(--text-review);
}

.page-content .danger-text, .page-content .text-button.danger-text {
  color: var(--text-danger);
}

.page-content .answer-textarea::placeholder { color: var(--text-muted); }
.page-content .privacy-note strong { color: var(--text-success); }
.page-content .solution-card code, .page-content .lesson-body-copy code:not(pre code),
.page-content .exercise-prompt code, .page-content .choice-text code {
  color: #40547d;
}

/* Calm, content-first surfaces and explicit appearance control. */
:root {
  --surface: #fff;
  --surface-raised: #fff;
  --surface-soft: #f1f2ef;
  --surface-field: #fbfcfe;
  --text-primary: #172337;
  --border-subtle: #e2e5e9;
}

.theme-control { display: inline-flex; align-items: center; gap: 8px; color: var(--text-muted); font-size: 14px; }
.theme-control select { min-height: 36px; padding: 4px 28px 4px 9px; border: 1px solid var(--border-subtle); border-radius: 7px; color: var(--text-primary); background: var(--surface); font: inherit; cursor: pointer; }
.theme-control select:focus-visible { outline: 3px solid var(--blue); outline-offset: 2px; }
.lesson-row-stage { color: var(--text-muted); font-size: 14px; font-weight: 600; }
.lesson-row-copy { gap: 3px; }

.sidebar,
.topbar,
.welcome-summary,
.track-card,
.recent-list,
.aside-card,
.track-hero-progress,
.track-overview p,
.lesson-list,
.lesson-navigation a,
.content-source,
.lesson-action-card,
.exercise-card,
.solution-card,
.side-goal-card,
.profile-stat-card,
.profile-panel,
.toast {
  background: var(--surface);
}

.sidebar,
.topbar,
.sidebar-bottom,
.welcome-summary,
.track-card,
.recent-list,
.aside-card,
.track-hero,
.track-hero-progress,
.track-overview p,
.lesson-list,
.lesson-row,
.lesson-index,
.lesson-body-copy,
.lesson-navigation a,
.content-source,
.lesson-action-card,
.question-type-pill,
.exercise-card,
.choice-option,
.choice-letter,
.answer-textarea,
.line-code,
.solution-card,
.side-goal-card,
.profile-stat-card,
.profile-panel,
.storage-info,
.theme-control select {
  border-color: var(--border-subtle);
}

.welcome-summary,
.resume-card,
.track-card,
.track-hero,
.track-hero-progress,
.track-overview p,
.lesson-list,
.lesson-body-copy,
.lesson-navigation a,
.content-source,
.lesson-action-card,
.exercise-card,
.solution-card,
.side-goal-card,
.profile-stat-card,
.profile-panel,
.aside-card,
.recent-list {
  border-radius: 8px;
  box-shadow: none;
}

.resume-card,
.tone-panel-yellow,
.tone-panel-blue,
.tone-panel-coral,
.tone-panel-green,
.tone-panel-cyan {
  background: var(--surface-soft);
  border-color: var(--border-subtle);
}

.resume-card { min-height: 190px; border-left: 4px solid var(--blue); }
.track-card:hover { transform: none; box-shadow: none; border-color: var(--blue); }
.lesson-row { border-bottom-color: var(--border-subtle); }
.lesson-row:hover,
.nav-link:hover,
.track-nav-link:hover,
.choice-option:hover,
.button-secondary:hover,
.lesson-navigation a:hover { background: var(--surface-soft); }
.track-hero-progress { background: var(--surface); }
.topic-row .lesson-row-stage { margin-bottom: 2px; }

:root[data-theme="dark"] {
  color-scheme: dark;
  color: #e7edf5;
  background: #11151b;
  --ink: #e7edf5;
  --muted: #b8c3d1;
  --line: #364254;
  --paper: #11151b;
  --white: #1a2029;
  --blue: #a9c0ff;
  --blue-dark: #c0d0ff;
  --navy: #dfe8f7;
  --green: #91d3ae;
  --shadow: none;
  --surface: #1a2029;
  --surface-raised: #202834;
  --surface-soft: #222a36;
  --surface-field: #151b23;
  --text-primary: #e7edf5;
  --text-muted: #b8c3d1;
  --text-success: #a8dfbd;
  --text-review: #f3cf86;
  --text-danger: #ffaaa0;
  --border-subtle: #3a4655;
}

:root[data-theme="dark"] body,
:root[data-theme="dark"] .app-shell { color: var(--text-primary); background: var(--paper); }
:root[data-theme="dark"] .sidebar,
:root[data-theme="dark"] .topbar { background: var(--surface); border-color: var(--border-subtle); }
:root[data-theme="dark"] .sidebar-bottom,
:root[data-theme="dark"] .welcome-summary,
:root[data-theme="dark"] .track-card,
:root[data-theme="dark"] .recent-list,
:root[data-theme="dark"] .aside-card,
:root[data-theme="dark"] .track-hero-progress,
:root[data-theme="dark"] .track-overview p,
:root[data-theme="dark"] .lesson-list,
:root[data-theme="dark"] .lesson-body-copy,
:root[data-theme="dark"] .lesson-navigation a,
:root[data-theme="dark"] .content-source,
:root[data-theme="dark"] .lesson-action-card,
:root[data-theme="dark"] .exercise-card,
:root[data-theme="dark"] .solution-card,
:root[data-theme="dark"] .side-goal-card,
:root[data-theme="dark"] .profile-stat-card,
:root[data-theme="dark"] .profile-panel,
:root[data-theme="dark"] .storage-info,
:root[data-theme="dark"] .toast { background: var(--surface); border-color: var(--border-subtle); }
:root[data-theme="dark"] .resume-card,
:root[data-theme="dark"] .tone-panel-yellow,
:root[data-theme="dark"] .tone-panel-blue,
:root[data-theme="dark"] .tone-panel-coral,
:root[data-theme="dark"] .tone-panel-green,
:root[data-theme="dark"] .tone-panel-cyan,
:root[data-theme="dark"] .daily-question,
:root[data-theme="dark"] .lesson-tip,
:root[data-theme="dark"] .coding-requirements,
:root[data-theme="dark"] .button-secondary,
:root[data-theme="dark"] .button-outline,
:root[data-theme="dark"] .lesson-nav-empty,
:root[data-theme="dark"] .answer-textarea { color: var(--text-primary); background: var(--surface-soft); border-color: var(--border-subtle); }
:root[data-theme="dark"] :is(
  .brand-name, .breadcrumbs strong, .welcome-copy h1, .welcome-summary strong,
  .resume-copy h2, .section-heading h2, .track-card-copy h3, .daily-card h2,
  .progress-card h2, .page-heading h1, .track-hero h1, .track-hero-progress strong,
  .track-overview strong, .lesson-row-title, .lesson-article > h1, .lesson-body-copy h2,
  .content-source h2, .lesson-action-card h2, .exercise-heading h1,
  .solution-heading h2, .backup-panel h2, .profile-stat-card > strong,
  .empty-state h1, .empty-state strong
) { color: var(--text-primary); }
:root[data-theme="dark"] :is(
  .nav-link, .track-nav-link, .breadcrumbs, .sidebar-label, .sidebar-label-row a,
  .sidebar-bottom p, .save-indicator, .site-footer, .site-footer a, .welcome-description,
  .summary-caption, .summary-foot, .resume-kicker, .resume-track, .resume-copy > p:last-of-type,
  .track-card-copy > p:last-child, .track-progress-row, .card-link, .daily-card > p,
  .progress-card > p, .daily-question strong, .daily-question small, .progress-stat,
  .progress-stat strong, .page-heading > p:last-child, .back-link, .track-hero-copy > p:not(.eyebrow),
  .track-hero-meta, .track-hero-progress > span, .track-overview p, .lesson-row-stage,
  .lesson-row-subtitle, .lesson-row-meta, .lesson-lead, .lesson-body-copy > p,
  .learning-points li, .lesson-tip p, .lesson-tip strong, .lesson-navigation span,
  .lesson-navigation strong, .content-source p, .content-source a, .lesson-action-card > p,
  .lesson-action-details span, .saved-small, .question-type-pill, .exercise-step,
  .exercise-progress-label, .exercise-prompt, .choice-text, .field-label, .field-hint,
  .answer-save-hint, .coding-requirements, .hint-disclosure summary, .hint-disclosure > p,
  .solution-disclosure summary, .solution-card > p, .side-goal-card h2, .side-goal-card > a,
  .side-privacy-note p, .stat-caption, .stat-foot, .empty-state p,
  .backup-panel > p:not(.eyebrow):not(.backup-caption), .backup-caption,
  .storage-info strong, .storage-info p, .muted-label
) { color: var(--text-muted); }
:root[data-theme="dark"] .nav-link.is-active { color: var(--blue); background: #2a3850; }
:root[data-theme="dark"] .button-primary { color: #111722; background: #b8caff; box-shadow: none; }
:root[data-theme="dark"] .button-primary:hover { color: #111722; background: #cbd7ff; box-shadow: none; }
:root[data-theme="dark"] .button-secondary { color: var(--text-primary); }
:root[data-theme="dark"] .button-outline { color: var(--text-primary); }
:root[data-theme="dark"] .choice-option,
:root[data-theme="dark"] .choice-letter { color: var(--text-primary); background: var(--surface-raised); border-color: var(--border-subtle); }
:root[data-theme="dark"] .choice-option:has(input:checked) { background: #28354a; border-color: #9ab4ff; box-shadow: 0 0 0 2px rgba(169, 192, 255, .16); }
:root[data-theme="dark"] .choice-option:has(input:checked) .choice-letter { color: #111722; background: #b8caff; border-color: #b8caff; }
:root[data-theme="dark"] .answer-textarea { color: var(--text-primary); background: var(--surface-field); }
:root[data-theme="dark"] .answer-textarea::placeholder { color: #aab6c6; }
:root[data-theme="dark"] .feedback-correct { color: var(--text-success); background: #1b3328; border-color: #345744; }
:root[data-theme="dark"] .feedback-review { color: var(--text-review); background: #382f1e; border-color: #5d4e2e; }
:root[data-theme="dark"] .answer-feedback.feedback-correct strong,
:root[data-theme="dark"] .answer-feedback.feedback-correct p { color: var(--text-success); }
:root[data-theme="dark"] .answer-feedback.feedback-review strong,
:root[data-theme="dark"] .answer-feedback.feedback-review p { color: var(--text-review); }
:root[data-theme="dark"] .answer-feedback .feedback-icon { color: #122319; background: #a8dfbd; }
:root[data-theme="dark"] .feedback-review .feedback-icon { color: #251c0e; background: #f3cf86; }
:root[data-theme="dark"] .completed-pill,
:root[data-theme="dark"] .lesson-index.is-done { color: #a8dfbd; background: #1b3328; border-color: #345744; }
:root[data-theme="dark"] .side-privacy-note { color: #a8dfbd; background: #1b3328; }
:root[data-theme="dark"] .side-privacy-note strong { color: #a8dfbd; }
:root[data-theme="dark"] .lesson-body-copy code:not(pre code),
:root[data-theme="dark"] .solution-card code,
:root[data-theme="dark"] .exercise-prompt code,
:root[data-theme="dark"] .choice-text code { color: #c5d4ff; background: #293449; }
:root[data-theme="dark"] .progress-track { background: #303a48; }
:root[data-theme="dark"] .mobile-nav { background: rgba(26, 32, 41, .98); border-color: var(--border-subtle); }
:root[data-theme="dark"] .theme-control select { color: var(--text-primary); background: var(--surface-raised); }
:root[data-theme="dark"] button:focus-visible,
:root[data-theme="dark"] a:focus-visible,
:root[data-theme="dark"] input:focus-visible,
:root[data-theme="dark"] textarea:focus-visible,
:root[data-theme="dark"] summary:focus-visible { outline-color: #b8caff; }
:root[data-theme="dark"] .lesson-row,
:root[data-theme="dark"] .lesson-index,
:root[data-theme="dark"] .question-type-pill { color: var(--text-muted); background: var(--surface-raised); border-color: var(--border-subtle); }
:root[data-theme="dark"] .lesson-row:hover,
:root[data-theme="dark"] .nav-link:hover,
:root[data-theme="dark"] .track-nav-link:hover,
:root[data-theme="dark"] .choice-option:hover,
:root[data-theme="dark"] .lesson-navigation a:hover { background: #263142; }

@media (max-width: 760px) {
  .topbar-actions { gap: 9px; }
  .theme-control > span { display: none; }
  .theme-control select { min-height: 40px; }
  .resume-card { min-height: 0; }
}