/* Shared styles for /summer/ — Vi An's Summer 2026 Learning Camp.
   Per-lesson accent: set --accent (and optional --accent-soft) on .wrap. Default = Learn teal. */
*{margin:0;padding:0;box-sizing:border-box}
body{font-family:'Lora',Georgia,serif;background:linear-gradient(135deg,#fef6e4 0%,#f3d2c1 50%,#fae3d9 100%);min-height:100vh;color:#001858;padding:40px 20px}
.wrap{--accent:#5fa8b3;--accent-soft:#8bd3dd;max-width:1080px;margin:0 auto;background:#fffaf0;border-radius:24px;box-shadow:0 20px 60px rgba(0,24,88,.15);padding:50px 50px;position:relative;overflow:hidden}
.wrap::before{content:'';position:absolute;top:-100px;right:-100px;width:300px;height:300px;background:radial-gradient(circle,var(--accent-soft) 33,transparent);opacity:.35;border-radius:50%;pointer-events:none}
.wrap::after{content:'';position:absolute;bottom:-80px;left:-80px;width:250px;height:250px;background:radial-gradient(circle,#f5a62333,transparent);border-radius:50%;pointer-events:none}

.back{display:inline-block;font-family:Helvetica,sans-serif;font-size:13px;letter-spacing:2px;text-transform:uppercase;color:#5a6c8c;text-decoration:none;margin-bottom:24px;position:relative;z-index:1}
.back:hover{color:var(--accent)}
header{text-align:center;margin-bottom:34px;position:relative;z-index:1}
.kicker{font-family:Helvetica,sans-serif;font-size:13px;letter-spacing:6px;color:var(--accent);text-transform:uppercase;margin-bottom:12px}
.lesson-emoji{font-size:60px;line-height:1;margin-bottom:8px}
h1{font-size:46px;margin-bottom:12px;letter-spacing:-1px;line-height:1.05}
.subtitle{font-size:18px;font-style:italic;opacity:.85;max-width:680px;margin:0 auto;line-height:1.5}

.scene{background:#fff;border-radius:18px;padding:34px 30px;margin-bottom:26px;box-shadow:0 6px 20px rgba(0,24,88,.08);position:relative;z-index:1}
.scene-num{font-family:Helvetica,sans-serif;font-size:12px;letter-spacing:2px;color:var(--accent);text-transform:uppercase;font-weight:600;margin-bottom:8px}
.scene h2{font-size:26px;margin-bottom:14px;line-height:1.25}
.scene p{font-size:17px;line-height:1.6;margin-bottom:14px;color:#172c66}
.scene p strong{color:var(--accent)}

/* Generic interactive scaffolding */
.demo{text-align:center;margin:20px 0}
.controls{display:flex;justify-content:center;align-items:center;gap:12px;margin-top:14px;flex-wrap:wrap}
.readout{font-family:Helvetica,sans-serif;font-size:30px;font-weight:700;color:#001858;min-width:70px}
.hint{font-size:14px;color:#5a6c8c;margin-top:10px;font-style:italic}
button{font-family:Helvetica,sans-serif;font-size:14px;font-weight:600;padding:10px 20px;border:none;border-radius:12px;cursor:pointer;transition:transform .15s,background .15s}
.btn-primary{background:var(--accent);color:#fff;box-shadow:0 4px 12px rgba(0,24,88,.18)}
.btn-primary:hover{transform:translateY(-2px)}
.btn-sm{padding:10px 14px;font-size:20px;font-weight:700}
input[type=range]{accent-color:var(--accent);width:min(420px,80%)}

/* Tap quiz */
.quiz{background:#f6fbfc;border:2px solid var(--accent-soft);border-radius:16px;padding:24px;margin:18px 0}
.quiz .q{font-size:21px;font-weight:700;color:#001858;margin-bottom:16px;text-align:center;line-height:1.3}
.opts{display:flex;gap:12px;justify-content:center;flex-wrap:wrap}
.opt{background:#fff;border:3px solid var(--accent-soft);border-radius:12px;padding:14px 22px;font-size:24px;font-weight:700;cursor:pointer;font-family:Helvetica,sans-serif;transition:all .15s;color:#001858;min-width:64px}
.opt:hover{border-color:var(--accent);transform:translateY(-2px)}
.opt.right{background:#dcfce7;border-color:#16a34a;color:#15803d}
.opt.wrong{background:#fee2e2;border-color:#dc2626;color:#dc2626}
.fb{margin-top:14px;font-size:17px;font-weight:600;text-align:center;min-height:26px;color:#16a34a}
.fb.no{color:#dc2626}
.score{font-family:Helvetica,sans-serif;font-size:13px;letter-spacing:1px;color:#5a6c8c;text-align:center;margin-top:10px;text-transform:uppercase}

/* Level Up challenge box — the gradual-difficulty ramp */
.challenge{background:linear-gradient(135deg,#fff7ed,#ffedd5);border:2px dashed #f5a623;border-radius:16px;padding:24px 26px;margin:22px 0;position:relative;z-index:1}
.challenge .tag{display:inline-block;font-family:Helvetica,sans-serif;font-size:11px;letter-spacing:2px;text-transform:uppercase;font-weight:700;color:#b45309;background:#fde68a;border-radius:999px;padding:4px 12px;margin-bottom:10px}
.challenge h3{font-size:21px;margin-bottom:10px;color:#92400e}
.challenge p{font-size:16px;line-height:1.55;color:#7c2d12;margin-bottom:10px}

/* Big Idea reveal */
.reveal{background:linear-gradient(135deg,#001858 0%,#172c66 100%);color:#fffaf0;padding:44px 38px;border-radius:18px;text-align:center;margin-top:36px;position:relative;z-index:1}
.reveal-kicker{font-family:Helvetica,sans-serif;font-size:12px;letter-spacing:6px;color:var(--accent-soft);text-transform:uppercase;margin-bottom:14px}
.reveal h2{font-size:30px;margin-bottom:16px;color:#fffaf0}
.reveal p{font-size:17px;line-height:1.7;max-width:680px;margin:12px auto;opacity:.92}
.reveal strong{color:var(--accent-soft)}

footer{margin-top:36px;text-align:center;font-family:Helvetica,sans-serif;font-size:12px;color:#5a6c8c;letter-spacing:2px;text-transform:uppercase;position:relative;z-index:1}
footer a{color:var(--accent);text-decoration:none}
.nav{display:flex;justify-content:space-between;gap:12px;margin-top:30px;position:relative;z-index:1}
.nav a{flex:1;font-family:Helvetica,sans-serif;font-size:13px;font-weight:700;text-decoration:none;color:#001858;background:#fff;border:2px solid var(--accent-soft);border-radius:12px;padding:14px 16px;transition:all .15s}
.nav a:hover{border-color:var(--accent);transform:translateY(-2px)}
.nav a.next{text-align:right}
.nav a .lbl{display:block;font-size:10px;letter-spacing:1.5px;text-transform:uppercase;color:#5a6c8c;margin-bottom:3px}

@media(max-width:700px){.wrap{padding:30px 20px}h1{font-size:34px}.scene{padding:24px 20px}.opt{font-size:20px;padding:12px 16px}}