:root{--navy:#122955;--blue:#2658b5;--blue-dark:#17418e;--sky:#eaf4ff;--teal:#04a9a4;--ink:#223452;--muted:#60738c;--cream:#fff8ef;--line:#dce6f2;--white:#fff;--pink:#fff0f4;--shadow:0 16px 44px rgba(25,65,126,.09);--radius:23px}
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.site-header{position:sticky;top:0;z-index:100;background:rgba(255,255,255,.97);border-bottom:1px solid rgba(201,214,233,.78);backdrop-filter:blur(14px)}.header-inner{min-height:88px;display:flex;align-items:center;gap:24px}.brand{display:inline-flex;align-items:center;gap:10px;flex-shrink:0;min-width:215px}.brand-symbol{display:flex;position:relative;align-items:center;justify-content:center;border-radius:16px;background:linear-gradient(140deg,#144993,#3295dd);width:44px;height:44px;font-size:27px;font-weight:900;color:#fff;line-height:1}.brand-dot{position:absolute;font-size:10px;color:#ffc65f;top:7px;right:5px}.brand-text{font-weight:900;font-size:16px;line-height:1.06;letter-spacing:-.025em;color:var(--navy)}.brand-text strong{color:var(--blue)}.brand-text small{display:block;color:#6681a4;font-weight:650;letter-spacing:.11em;font-size:9px;text-transform:uppercase;margin-top:6px}.nav{display:flex;gap:3px;align-items:center;margin-left:auto}.nav-link{display:block;white-space:nowrap;padding:10px 13px;border-radius:12px;color:#55667f;font-weight:700;font-size:14px;transition:.2s}.nav-link:hover{background:#eff5ff;color:var(--blue-dark)}.nav-link[aria-current=page]{background:#eaf1ff;color:#1c50aa}.header-cta,.btn{display:inline-flex;justify-content:center;align-items:center;gap:8px;border-radius:14px;font-weight:800;white-space:nowrap;transition:transform .18s,box-shadow .18s,background .18s}.header-cta{padding:12px 16px;background:var(--navy);color:#fff;font-size:13px}.header-cta:hover,.btn:hover{transform:translateY(-2px)}.btn{border:1px solid transparent;padding:13px 19px;font-size:14px;line-height:1.3}.btn-primary{background:#1e55b0;color:#fff;box-shadow:0 8px 18px rgba(23,73,155,.17)}.btn-primary:hover{background:#143f90}.btn-soft{background:#eaf3ff;color:#164994}.btn-soft:hover{background:#d9eaff}.btn-outline{background:#fff;color:#285199;border-color:#b9cde7}.btn-outline:hover{background:#f2f7ff}.btn-deep{background:#2f2b67;color:#fff}.btn-deep:hover{background:#191648}.btn-sm{padding:9px 13px;font-size:13px}.muted{color:var(--muted)}.overline{display:block;color:#2469b9;text-transform:uppercase;font-weight:900;font-size:12px;letter-spacing:.16em;margin-bottom:12px}.overline.light{color:#b9e6ff}
.hero-backdrop{background:linear-gradient(115deg,#eef8ff 0%,#f5fbff 51%,#e4f5f0 100%);overflow:hidden}.hero-grid{padding:85px 0 75px;display:grid;grid-template-columns:1.06fr 1fr;align-items:center;gap:65px}.eyebrow{display:inline-flex;align-items:center;gap:7px;border:1px solid #cbdff1;border-radius:50px;background:#fff;padding:6px 13px;color:#2d629b;font-size:11px;letter-spacing:.07em;font-weight:900;max-width:100%}.eyebrow-star{color:#f3a92b;font-size:18px}.hero-copy h1{font-size:clamp(44px,5.8vw,72px);letter-spacing:-.06em;margin:17px 0 20px;line-height:1.08}.hero-copy h1 span{color:#2276c9}.hero-lead{font-size:18px;color:#536b88;max-width:535px}.hero-lead strong{color:#1d4ca0}.hero-actions{display:flex;flex-wrap:wrap;gap:12px;margin:26px 0 20px}.hero-helper{font-size:12px;color:#627d96;margin:0 0 28px}.mini-stats{display:flex;gap:40px;border-top:1px solid #d4e3ef;max-width:480px;padding-top:24px}.mini-stats div{display:flex;align-items:baseline;gap:8px}.mini-stats strong{font-size:30px;color:#1c56af;line-height:1}.mini-stats span{font-size:12px;font-weight:700;color:#627d96}.hero-visual{position:relative;min-height:435px;display:flex;align-items:center;justify-content:center}.visual-glow{position:absolute;border-radius:50%;height:420px;width:420px;background:#d0edfa;right:4%;top:9%;filter:blur(1px)}.video-card-art{position:relative;z-index:2;width:85%;margin-top:12px;border:9px solid white;box-shadow:0 22px 55px rgba(35,80,143,.22);border-radius:24px;overflow:hidden;transform:rotate(-3deg);background:#fff}.video-card-art img{width:100%;height:300px;object-fit:cover;display:block}.video-caption{background:#fff;padding:12px 17px;font-size:13px;font-weight:900;color:#28558d;display:flex;align-items:center;justify-content:space-between}.video-status{color:#1fba9f}.floating-bubble{z-index:3;position:absolute;border-radius:18px;background:white;box-shadow:0 9px 24px rgba(23,67,119,.12);padding:11px 17px;font-weight:900;color:#183d7a;font-size:15px}.floating-bubble span{font-size:21px;margin-right:8px}.bubble-top{right:-3%;top:13%;transform:rotate(4deg)}.bubble-bottom{left:0%;bottom:8%;transform:rotate(4deg)}.hero-spark{position:absolute;color:#f2ac37;font-size:34px}.hero-spark.one{top:0;left:9%}.hero-spark.two{bottom:5%;right:2%}
.home-main{padding:72px 0 88px}.section-heading{margin-bottom:32px}.section-heading.centered{text-align:center}.section-heading h2{font-size:36px;margin-bottom:8px}.section-heading p{color:var(--muted)}.steps-grid{display:grid;grid-template-columns:repeat(5,1fr);gap:15px}.step-card{position:relative;background:#fff;border:1px solid #e5edf5;border-radius:20px;padding:22px 18px;box-shadow:0 7px 19px rgba(36,83,140,.045);min-height:200px}.step-num{position:absolute;right:15px;top:15px;color:#cbd8e8;font-size:13px;font-weight:900}.step-icon{background:#eaf4ff;color:#1d61bf;width:52px;height:52px;display:flex;align-items:center;justify-content:center;border-radius:15px;font-size:22px;font-weight:900;margin-bottom:17px}.step-card:nth-child(2) .step-icon{background:#e5faf8;color:#009d9b}.step-card:nth-child(3) .step-icon{background:#fff2e0;color:#f2a227}.step-card:nth-child(4) .step-icon{background:#ffecf3;color:#d4578a}.step-card:nth-child(5) .step-icon{background:#eee9ff;color:#8666ce}.step-card h3{font-size:18px;margin-bottom:5px}.step-card p{color:#637891;font-size:13px;margin:0}.home-split{margin-top:76px;display:grid;grid-template-columns:1fr 1fr;gap:45px;align-items:center}.story-panel{padding:25px 5px}.story-panel h2{font-size:clamp(28px,3.5vw,44px);max-width:510px}.story-panel p{color:#5a6f86;max-width:510px}.text-link{display:inline-block;color:#205ab1;font-weight:900;padding:8px 0}.photo-panel{position:relative;border-radius:25px;overflow:hidden;box-shadow:var(--shadow);background:#eaf3ff}.photo-panel img{display:block;width:100%;height:340px;object-fit:cover}.photo-tag{position:absolute;bottom:18px;left:17px;background:rgba(255,255,255,.95);border-radius:13px;padding:7px 13px;color:#165294;font-weight:900;font-size:13px}
.page-top{padding:54px 0 51px}.page-top h1{font-size:clamp(35px,4.4vw,54px);margin:0 0 13px}.page-top p{max-width:750px;margin:0;font-size:16px}.blue-top{background:linear-gradient(110deg,#15438c,#2c74b9);color:#fff}.blue-top h1,.blue-top p{color:#fff}.pink-top{background:linear-gradient(110deg,#fff0f2,#eff8ff)}.aqua-top{background:linear-gradient(120deg,#e7faf6,#eef5ff)}.purple-top{background:linear-gradient(115deg,#253780,#5557a8);color:#fff}.purple-top h1,.purple-top p{color:#fff}.content-section{padding:39px 0 86px}.lesson-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:17px;margin-bottom:32px}.lesson-tile{background:white;border:1px solid #dde9f5;border-radius:19px;padding:18px;text-align:left;display:flex;gap:12px;align-items:flex-start;transition:.2s;min-height:122px}.lesson-tile:hover,.lesson-tile.active{border-color:#7facdd;box-shadow:0 9px 26px rgba(36,89,158,.12);transform:translateY(-2px)}.lesson-tile.active{background:#f0f7ff}.lesson-tile .lesson-emoji{width:46px;height:46px;display:flex;align-items:center;justify-content:center;border-radius:15px;background:#eaf4ff;font-size:24px;flex:none}.lesson-tile:nth-child(2) .lesson-emoji{background:#fff0e5}.lesson-tile:nth-child(3) .lesson-emoji{background:#eafaf4}.lesson-tile:nth-child(4) .lesson-emoji{background:#f7eeff}.lesson-tile:nth-child(5) .lesson-emoji{background:#fff4e5}.lesson-tile:nth-child(6) .lesson-emoji{background:#f4f2ff}.lesson-tile small{display:block;font-size:11px;color:#4f79af;font-weight:900;letter-spacing:.08em;text-transform:uppercase}.lesson-tile strong{display:block;font-size:15px;color:#1d3b6e;margin:2px 0}.lesson-tile em{display:block;font-style:normal;font-size:12px;color:#708198}.lesson-panel{background:white;border:1px solid #dce8f5;border-radius:25px;box-shadow:var(--shadow);padding:30px}.lesson-panel-header{display:flex;justify-content:space-between;align-items:center;gap:20px;border-bottom:1px solid #e4ecf4;padding-bottom:21px;margin-bottom:25px}.lesson-panel-header h2{margin:0 0 5px;font-size:30px}.lesson-panel-header p{margin:0}.panel-tools{display:flex;gap:8px;flex-wrap:wrap}.lesson-layout{display:grid;grid-template-columns:minmax(0,1.9fr) minmax(260px,1fr);gap:25px}.video-region{border-radius:20px;overflow:hidden;background:#e8f2ff}.video-placeholder{text-align:center;padding:38px 22px 31px;min-height:255px;background:radial-gradient(circle at 80% 0,#d5f1ff 0,transparent 35%),linear-gradient(130deg,#e5efff,#f0fbff)}.play-symbol{border-radius:50%;width:68px;height:68px;background:#2264c4;color:#fff;display:flex;align-items:center;justify-content:center;font-size:27px;margin:0 auto 13px;padding-left:4px;box-shadow:0 9px 20px #1f61c240}.video-placeholder h3{font-size:21px;margin-bottom:7px}.video-placeholder p{font-size:14px;color:#58718e;max-width:440px;margin:0 auto 10px}.placeholder-caption{display:block;font-size:11px;color:#64819b}.placeholder-caption code{font-size:11px}#lessonVideo{display:block;width:100%;max-height:460px;background:#0b1630;aspect-ratio:16/9}#lessonVideo[hidden]{display:none}.dialogue-head{margin:27px 0 14px;display:flex;align-items:center;justify-content:space-between;gap:10px}.dialogue-head h3{font-size:19px;margin:0}.dialogue-list{display:grid;gap:10px}.dialogue-row{display:grid;grid-template-columns:39px 1fr auto;align-items:start;gap:12px;border:1px solid #e3ebf4;border-radius:15px;padding:12px;background:#fff}.dialogue-row:nth-child(even){background:#f8fbff}.speaker-avatar{width:35px;height:35px;border-radius:12px;display:flex;align-items:center;justify-content:center;background:#e6efff;color:#1b58ac;font-size:15px;font-weight:900}.dialogue-row:nth-child(even) .speaker-avatar{background:#fce6ef;color:#ad426a}.speaker-name{font-weight:900;color:#1b519a;font-size:12px;display:block}.en-line{font-weight:700;font-size:15px;line-height:1.52;margin:3px 0 4px}.vi-line{color:#71849b;font-size:13px;margin:0;line-height:1.5}.hide-translation .vi-line{display:none}.listen-line{border:1px solid #dae6f5;background:#fff;color:#2456a3;border-radius:12px;width:36px;height:36px;font-size:17px;flex:none}.listen-line:hover{background:#eaf4ff}.lesson-end-actions{display:flex;flex-wrap:wrap;gap:9px;margin-top:22px}.lesson-aside{display:grid;gap:16px;align-content:start}.aside-block{background:#f5f9ff;border:1px solid #e0ecf7;padding:21px;border-radius:18px}.aside-block h3{font-size:16px;margin-bottom:14px}.vocab-item{display:flex;gap:10px;justify-content:space-between;padding:9px 0;border-bottom:1px dashed #ceddef;font-size:13px}.vocab-item:last-child{border:0;padding-bottom:0}.vocab-item strong{color:#234d93}.vocab-item span{text-align:right;color:#627892}.five-steps{background:#f1fbf9;border-color:#d7f2ec}.five-steps ol{padding-left:23px;margin:0;display:grid;gap:8px;font-size:13px;color:#4b697d}.five-steps strong{color:#096f79}.challenge-block{background:#fff8e8;border-color:#f8e3b2}.challenge-block .overline{color:#a87916}.challenge-block p{font-size:14px;font-weight:700;color:#6b571f;margin:0}
.practice-controls{display:flex;align-items:center;gap:13px;margin-bottom:25px;flex-wrap:wrap}.practice-controls label{font-weight:800;color:#294a77}.practice-controls select{min-width:265px;border:1px solid #becfe4;border-radius:12px;background:#fff;padding:12px 14px;color:#233f68}.practice-layout{display:grid;grid-template-columns:minmax(0,1.5fr) minmax(260px,.8fr);gap:23px;align-items:start}.practice-card{background:white;border:1px solid var(--line);border-radius:24px;box-shadow:var(--shadow);padding:29px}.practice-card-top h2{font-size:27px}.practice-card-top p{font-size:14px}.roles-line{display:flex;gap:10px;justify-content:center;align-items:center;margin:20px 0}.role-chip{border-radius:12px;font-size:13px;padding:10px 13px;font-weight:900}.role-a{background:#e8efff;color:#2956a3}.role-b{background:#ffedf1;color:#b74468}.switch-roles{color:#8a9fbb;font-size:22px}.pair-dialogue{display:grid;gap:8px}.pair-line{border-radius:12px;padding:11px 13px;background:#f1f6ff;color:#294b77;font-size:14px}.pair-line.b{background:#fff1f5;color:#803e5f}.pair-line strong{display:block;font-size:12px;color:#315caa}.pair-line.b strong{color:#b64578}.practice-guide{display:grid;gap:17px}.practice-hint-card{border:1px solid #e7dff5;background:#f6f0ff;border-radius:20px;padding:22px}.practice-hint-card h3{font-size:18px;margin:8px 0}.practice-hint-card p{font-size:14px;color:#65617d;margin:0}.hint-icon{font-size:27px;color:#8058cd}.feedback-card{background:#f4fbf9;border-color:#dceeea}.feedback-card label{display:flex;gap:11px;align-items:flex-start;padding:8px 0;color:#38596e;font-size:14px;cursor:pointer}.feedback-card input{width:18px;height:18px;accent-color:#249a84;flex:none;margin-top:2px}.feedback-card .btn{margin-top:12px;margin-right:7px}
.chatbot-shell{max-width:875px}.chat-window{background:white;border-radius:23px;border:1px solid #dce7f4;box-shadow:var(--shadow);overflow:hidden}.chat-head{padding:15px 20px;background:#f2f8ff;display:flex;align-items:center;gap:12px;border-bottom:1px solid #dfe9f5}.bot-avatar{width:43px;height:43px;border-radius:15px;display:grid;place-items:center;color:#fff;background:linear-gradient(140deg,#2156ac,#27b6ae);font-size:27px}.chat-head strong{display:block;color:#203f73;font-size:14px}.chat-head span{font-size:11px;color:#71849b;display:block}.chat-head .bot-online{margin-left:auto;color:#1cb58d;font-size:17px}.chat-messages{height:340px;overflow-y:auto;padding:21px;display:flex;flex-direction:column;gap:13px;background:linear-gradient(#fff,#fbfdff)}.message{display:flex;gap:9px;max-width:85%;align-items:flex-end}.message.user{margin-left:auto;flex-direction:row-reverse}.message-avatar{height:29px;width:29px;border-radius:10px;background:#e4f4ee;display:grid;place-items:center;flex:none;color:#118c80;font-size:14px}.message.user .message-avatar{background:#e8efff;color:#2a60ae}.message-text{padding:11px 15px;border-radius:17px 17px 17px 3px;background:#edf7f4;color:#295c62;white-space:pre-wrap;line-height:1.55;font-size:14px}.message.user .message-text{background:#245ab4;border-radius:17px 17px 3px 17px;color:#fff}.quick-questions{padding:0 19px 15px;display:flex;gap:8px;flex-wrap:wrap}.quick-questions button{font-size:12px;padding:6px 11px;color:#37629a;background:#fff;border:1px solid #cfdfef;border-radius:18px}.quick-questions button:hover{background:#edf6ff}.chat-input-form{display:flex;gap:11px;padding:14px 18px 17px;border-top:1px solid #e8eff7}.chat-input-form input{flex:1;min-width:0;border:1px solid #d5e2ef;padding:13px 16px;border-radius:13px;color:#294b76}.gemini-box{display:flex;gap:18px;margin-top:24px;padding:24px;border:1px solid #dedcf2;background:linear-gradient(115deg,#f8f6ff,#f6faff);border-radius:22px}.gemini-icon{background:linear-gradient(125deg,#ece3ff,#d8ddff);color:#6c44ac;width:55px;height:55px;border-radius:18px;flex:none;display:grid;place-items:center;font-size:35px}.gemini-copy{flex:1}.gemini-copy h3{margin:0 0 6px;font-size:19px}.gemini-copy p{margin:0 0 16px;color:#647187;font-size:14px}.gemini-actions{display:flex;gap:10px;flex-wrap:wrap}.copy-status{margin:11px 0 0!important;font-size:12px!important;min-height:16px;color:#317158!important}.gemini-box details{margin-top:12px}.gemini-box summary{font-size:13px;color:#365d91;cursor:pointer;font-weight:700}.gemini-box textarea{width:100%;resize:vertical;background:#fff;border:1px solid #d6dced;border-radius:12px;color:#365073;padding:10px;font-size:12px;line-height:1.5;margin-top:8px}.privacy-tip{font-size:12px;color:#637890;margin-top:16px}
.progress-summary{background:linear-gradient(100deg,#f0f7ff,#effefa);border:1px solid #d9ebf6;border-radius:23px;padding:27px 33px;display:flex;align-items:center;justify-content:space-between;gap:20px}.progress-summary h2{font-size:42px;margin:2px 0 17px;color:#2357ac}.progress-summary h2 small{font-size:15px;color:#5a7894;font-weight:600}.progress-summary p{margin:12px 0 0;font-size:13px;color:#55768f}.progress-track{width:min(650px,67vw);height:12px;background:#dce9f5;border-radius:20px;overflow:hidden}.progress-track span{display:block;width:0;height:100%;background:linear-gradient(90deg,#2361c9,#19b4a4);transition:width .3s;border-radius:20px}.progress-cup{font-size:95px;line-height:1}.progress-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:17px;margin:24px 0}.progress-card{border:1px solid #deebf4;background:white;border-radius:19px;padding:20px;display:flex;justify-content:space-between;gap:15px;align-items:flex-start}.progress-card h3{font-size:16px;margin:4px 0 5px}.progress-card p{font-size:12px;color:#72859b;margin:0}.progress-card .card-check{border-radius:10px;height:40px;min-width:40px;border:1px solid #bfd3e8;background:#f2f7ff;color:#3164ae;font-size:20px;font-weight:900}.progress-card.done{background:#f1fdf8;border-color:#9edbc5}.progress-card.done .card-check{background:#1d9e7e;border-color:#1d9e7e;color:#fff}.progress-bottom{display:flex;align-items:center;justify-content:space-between;gap:15px;padding:15px 2px}.progress-bottom p{font-size:12px;color:#788aa0;max-width:650px;margin:0}
.site-footer{border-top:1px solid #dce6f1;background:#f6f9fc}.footer-inner{display:flex;justify-content:space-between;gap:30px;padding:30px 0}.footer-inner strong{font-size:15px;color:#1b3b73}.footer-inner p{font-size:12px;color:#7a899a;margin:5px 0}.footer-right{display:flex;flex-wrap:wrap;align-content:flex-start;align-items:center;gap:20px;font-size:12px;font-weight:750;color:#58748f}.footer-right span{color:#96a5b4}.toast{position:fixed;right:22px;bottom:22px;z-index:999;padding:13px 17px;border-radius:12px;background:#183d78;color:#fff;font-size:13px;box-shadow:var(--shadow);opacity:0;pointer-events:none;transform:translateY(12px);transition:.2s}.toast.show{opacity:1;transform:translateY(0)}#printSheet{display:none}
@media(max-width:1100px){.header-inner{gap:14px}.brand{min-width:200px}.nav-link{padding:8px 9px;font-size:13px}.header-cta{display:none}.hero-grid{gap:28px}.hero-visual{min-height:360px}.video-card-art img{height:260px}.visual-glow{width:350px;height:350px}.lesson-layout{grid-template-columns:1.65fr 1fr}}
@media(max-width:800px){.header-inner{display:block;padding:12px 0 9px;min-height:auto}.brand{margin-bottom:9px}.nav{width:100%;overflow-x:auto;margin:0;scrollbar-width:none}.nav::-webkit-scrollbar{display:none}.nav-link{padding:8px 15px}.hero-grid{padding:50px 0;grid-template-columns:1fr;gap:28px}.hero-copy h1{font-size:56px}.hero-visual{min-height:340px;max-width:600px;margin:auto;width:100%}.video-card-art img{height:265px}.bubble-top{right:2%}.steps-grid{grid-template-columns:repeat(3,1fr)}.home-split{grid-template-columns:1fr;gap:18px;margin-top:45px}.story-panel{padding:5px 0}.lesson-grid{grid-template-columns:repeat(2,1fr)}.lesson-layout,.practice-layout{grid-template-columns:1fr}.lesson-aside{grid-template-columns:repeat(2,1fr)}.challenge-block{grid-column:1/-1}.progress-grid{grid-template-columns:repeat(2,1fr)}}
@media(max-width:540px){body{font-size:15px}.shell{width:calc(100% - 28px)}.brand-symbol{width:38px;height:38px}.brand-text{font-size:15px}.nav-link{font-size:13px;padding:8px 12px}.hero-grid{padding:35px 0 44px}.eyebrow{font-size:9px}.hero-copy h1{font-size:43px}.hero-lead{font-size:15px}.hero-actions{gap:8px}.hero-actions .btn{font-size:12px;padding:12px 13px}.hero-helper{line-height:2}.mini-stats{gap:18px}.mini-stats strong{font-size:26px}.mini-stats span{font-size:10px}.hero-visual{min-height:240px}.visual-glow{width:250px;height:240px}.video-card-art{border-width:6px;width:83%;border-radius:17px}.video-card-art img{height:185px}.video-caption{font-size:11px;padding:7px 10px}.floating-bubble{font-size:10px;padding:6px 9px;border-radius:10px}.floating-bubble span{font-size:14px;margin-right:3px}.bubble-top{top:8%}.bubble-bottom{bottom:2%}.home-main{padding:48px 0}.section-heading h2{font-size:29px}.steps-grid{grid-template-columns:repeat(2,1fr);gap:10px}.step-card{padding:16px;min-height:155px}.step-icon{margin-bottom:10px;width:41px;height:41px;font-size:18px}.step-card h3{font-size:16px}.step-card p{font-size:12px}.photo-panel img{height:245px}.page-top{padding:37px 0}.page-top h1{font-size:34px}.page-top p{font-size:14px}.content-section{padding:25px 0 54px}.lesson-grid{grid-template-columns:1fr;gap:9px}.lesson-tile{min-height:80px;padding:13px}.lesson-panel{padding:16px;border-radius:18px}.lesson-panel-header{display:block}.lesson-panel-header h2{font-size:25px}.panel-tools{margin-top:14px}.lesson-aside{grid-template-columns:1fr}.video-placeholder{padding:27px 15px;min-height:220px}.dialogue-head{display:block}.dialogue-head h3{margin-bottom:10px}.dialogue-row{grid-template-columns:29px 1fr 32px;gap:8px;padding:10px}.speaker-avatar{width:29px;height:29px;border-radius:9px}.en-line{font-size:14px}.listen-line{width:32px;height:32px}.practice-card{padding:19px}.practice-controls select{min-width:0;width:100%}.practice-controls .btn{width:100%}.practice-layout{gap:15px}.chat-messages{height:330px;padding:13px}.message{max-width:93%}.message-text{font-size:13px;padding:10px 12px}.chat-input-form{padding:11px;gap:6px}.chat-input-form input{padding:11px}.chat-input-form .btn{padding:11px}.gemini-box{padding:16px;gap:10px}.gemini-icon{width:37px;height:37px;font-size:27px}.gemini-copy h3{font-size:17px}.gemini-actions .btn{font-size:12px;padding:9px 11px}.progress-summary{padding:19px}.progress-summary h2{font-size:33px}.progress-summary h2 small{display:block;margin-top:5px}.progress-track{width:100%;min-width:200px}.progress-cup{font-size:48px}.progress-grid{grid-template-columns:1fr;gap:10px}.progress-bottom{display:block}.progress-bottom button{margin-top:12px}.footer-inner{display:block}.footer-right{gap:12px;margin-top:18px}.toast{right:10px;left:10px;bottom:9px;text-align:center}}
@media(prefers-reduced-motion:reduce){*,*:before,*:after{scroll-behavior:auto!important;transition-duration:.01ms!important;animation-duration:.01ms!important}}
@page{size:A4;margin:14mm}@media print{body.print-mode>*:not(#printSheet){display:none!important}body.print-mode #printSheet{display:block!important;font:12pt/1.45 "Times New Roman",serif;color:#000}#printSheet h1{font-size:20pt}#printSheet h2{font-size:15pt;margin:10pt 0}#printSheet .print-dialogue p{margin:4pt 0}#printSheet .print-vi{color:#555}#printSheet .print-vocab{display:grid;grid-template-columns:1fr 1fr;gap:5pt}#printSheet .print-item{border:1px solid #ccc;padding:5pt;break-inside:avoid}#printSheet .print-section{margin-bottom:15pt}#printSheet .print-header{text-align:center;border-bottom:1pt solid #444;margin-bottom:15pt}}
/* Five navigation items always visible on narrow phone screens. */
@media (max-width:540px) {
  .nav {display:grid;grid-template-columns:repeat(5,minmax(0,1fr));gap:2px;overflow:visible}
  .nav-link {min-width:0;padding:8px 2px;text-align:center;white-space:normal;font-size:11px;line-height:1.2}
}

/* Nhom nghien cuu va giao vien huong dan o chan trang. */
.footer-credits{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:20px;border-top:1px solid #dce6f1;padding:22px 0 28px}
.footer-credit-block{min-width:0}
.footer-credit-block h2{font-size:13px;letter-spacing:.02em;margin:0 0 8px;color:#2a5ba3;font-weight:850}
.footer-credit-block p{font-size:14px;line-height:1.85;margin:0;color:#405675}
.footer-credit-block strong{font-size:14px;font-weight:720;color:#213f6b}
.footer-role{font-size:12px;color:#6d7e96}
@media(max-width:600px){.footer-credits{grid-template-columns:1fr;gap:17px;padding:20px 0 28px}}