:root { --bg:#ffffff; --text:#0a0a0a; --muted:#5f6c7b; --border:#e6e8eb; --accent:#0a2540; --accent-2:#635bff; --shadow:0 10px 30px rgba(16,24,40,.08); --shadow-strong:0 18px 50px rgba(16,24,40,.16); }
*{box-sizing:border-box}
body{margin:0;font-family:Inter,system-ui,-apple-system,Segoe UI,Roboto,Ubuntu,Arial,sans-serif;background:var(--bg);color:var(--text)}
header,main,footer{max-width:1200px;margin:0 auto;padding:24px}
.container{max-width:1200px;margin:0 auto;padding:24px}
.fullbleed{max-width:100vw;padding-left:0;padding-right:0}
header.site-header{position:sticky;top:0;z-index:50;backdrop-filter:blur(8px);background:rgba(255,255,255,.7)}
nav{display:flex;align-items:center;justify-content:space-between;gap:12px}
.brand{font-weight:800;display:flex;align-items:center;color:var(--text);text-decoration:none}
.brand .logo{height:28px;width:auto;vertical-align:middle;margin-right:8px}
.nav-links{display:flex;align-items:center;gap:14px}
.nav-links a{color:var(--text);text-decoration:none;font-weight:600}
.nav-links a.btn{color:#fff}
.menu-btn{display:none;align-items:center;gap:6px;padding:8px 12px;border-radius:10px;border:1px solid var(--border);background:#fff;color:var(--text)}
/* Icon-only hamburger styling */
.menu-btn{width:40px;height:40px;padding:0;display:none;place-items:center}
.menu-icon{position:relative;width:22px;height:2px;background:#0a2540;border-radius:2px;transition:transform .2s ease, opacity .2s ease}
.menu-icon::before,.menu-icon::after{content:"";position:absolute;left:0;width:22px;height:2px;background:#0a2540;border-radius:2px;transition:transform .2s ease, opacity .2s ease}
.menu-icon::before{top:-6px}
.menu-icon::after{top:6px}
.menu-btn.open .menu-icon{background:transparent}
.menu-btn.open .menu-icon::before{transform:translateY(6px) rotate(45deg)}
.menu-btn.open .menu-icon::after{transform:translateY(-6px) rotate(-45deg)}
.btn{display:inline-flex;align-items:center;gap:8px;background:#0a2540;color:#fff;padding:12px 16px;border-radius:999px;font-weight:700;box-shadow:var(--shadow);transition:transform .18s ease, box-shadow .18s ease}
.btn:hover{transform:translateY(-1px) scale(1.04);box-shadow:var(--shadow-strong)}
.btn:active{transform:translateY(0) scale(0.98)}
.btn.secondary{background:#fff;color:#0a2540;border:1px solid var(--border);box-shadow:none}
.btn.ghost{background:transparent;color:#0a2540;border:1px solid #cfd3d8}
.btn.small{padding:8px 12px;font-weight:700}
.card{background:#fff;border:1px solid var(--border);border-radius:16px;padding:20px;margin:16px 0;box-shadow:var(--shadow)}
input,button{font:inherit}
input[type=email],input[type=password],input[type=text]{width:100%;padding:12px 14px;border-radius:10px;border:1px solid var(--border);background:#fff;color:var(--text);margin:6px 0}
button{cursor:pointer;background:#0a2540;color:#fff;border:none;padding:12px 16px;border-radius:999px;font-weight:700}
.alert{padding:12px 14px;border-radius:12px;border:1px solid transparent;font-weight:700;margin-top:8px}
.alert-success{background:#ecfdf3;border-color:#abefc6;color:#027a48;box-shadow:0 1px 2px rgba(2,122,72,.08)}
.alert-error{background:#fef3f2;border-color:#fecdca;color:#b42318;box-shadow:0 1px 2px rgba(180,35,24,.08)}
.pw-req{display:flex;flex-direction:column;gap:6px;margin:6px 0 8px 2px;font-size:14px}
.pw-req span{display:flex;align-items:center;gap:8px}
.pw-req .ok{color:#1a7f37}
.pw-req .bad{color:#b42318}
.grid{display:grid;gap:16px;grid-template-columns:repeat(auto-fill,minmax(260px,1fr))}
.muted{color:var(--muted)}
.center{display:flex;align-items:center;justify-content:center}

/* Auth layout (register/login) */
.auth-layout{position:relative;min-height:calc(100vh - 220px);display:grid;grid-template-columns:1.1fr 0.9fr;gap:24px;align-items:center}
@media (max-width: 900px){.auth-layout{grid-template-columns:1fr}}
.benefit-list{list-style:none;padding:0;margin:10px 0 0}
.benefit-list li{margin:12px 0}
.benefits h3{margin:0 0 6px}

/* Decorative circles for auth pages (bottom-right) */
.decor-circles{position:absolute;right:0;bottom:-8px;width:420px;height:420px;pointer-events:none;z-index:-1}
.decor-circles span{position:absolute;border-radius:50%;border:4px solid transparent;background-clip:padding-box}
/* Toucan beak colors */
::root{--beak1:#e61b3b;--beak2:#00d4ff;--beak3:#2ad86b;--beak4:#ffe55c}
.decor-circles .a{width:200px;height:200px;right:24px;bottom:22px;border-color:var(--beak1);background:rgba(230,27,59,.12)}
.decor-circles .b{width:120px;height:120px;right:180px;bottom:170px;border-color:var(--beak2)}
.decor-circles .c{width:100px;height:100px;right:260px;bottom:40px;border-color:var(--beak3);background-image:radial-gradient(var(--beak3) 1.6px, transparent 1.6px);background-size:10px 10px}
.decor-circles .d{width:48px;height:48px;right:80px;bottom:232px;border-color:var(--beak4)}
@media (max-width: 900px){
  .decor-circles{width:300px;height:300px}
  .decor-circles .a{width:150px;height:150px;right:18px;bottom:18px}
  .decor-circles .b{width:96px;height:96px;right:130px;bottom:132px}
  .decor-circles .c{width:78px;height:78px;right:200px;bottom:34px}
  .decor-circles .d{width:40px;height:40px;right:64px;bottom:168px}
}
@media (max-width: 640px){
  .decor-circles{width:220px;height:220px}
  .decor-circles .a{width:110px;height:110px;right:14px;bottom:14px}
  .decor-circles .b{width:70px;height:70px;right:92px;bottom:96px}
  .decor-circles .c{width:60px;height:60px;right:150px;bottom:26px;background-size:8px 8px}
  .decor-circles .d{width:28px;height:28px;right:52px;bottom:126px}
  .decor-circles{bottom:-20px}
}

/* Hero with diagonal gradient + lava blobs */
.hero-wrap{position:relative;overflow:hidden;min-height:95vh}
.hero-bg{position:absolute;inset:0;z-index:0;pointer-events:none}
.hero-bg::before{content:"";position:absolute;inset:-10% -10% 28% -10%;
  background:linear-gradient(135deg,#f3f7ff 0%, #e8f0ff 40%, #ffe6f0 100%);
  clip-path:polygon(0 0,100% 0,100% 78%,0 92%);} 
.hero-wedge{position:absolute;inset:0;background:linear-gradient(135deg,#ff2047 0%, #ff7a3d 30%, #ffd166 55%, #7b6cf6 100%);opacity:.85;clip-path:polygon(0 0, 100% 0, 58% 55%, 0 78%);filter:saturate(1.15)}
.hero-animated{animation:hueRotateSlow 30s linear infinite}
@keyframes hueRotateSlow{0%{filter:hue-rotate(0)}100%{filter:hue-rotate(360deg)}}
.hero-mask{position:absolute;inset:0;z-index:0;pointer-events:none;background:radial-gradient(1000px 520px at 55% 45%, rgba(255,255,255,0) 0%, rgba(255,255,255,0) 60%, rgba(255,255,255,.6) 100%);}
@media (prefers-reduced-motion: reduce){.hero-animated{animation:none}}

/* Lava lamp blobs */
.lava{position:absolute;inset:0;filter:blur(32px);mix-blend-mode:screen;opacity:0.9}
.blob{position:absolute;border-radius:50%;will-change:transform;transform:translate3d(0,0,0) scale(1);} 
.blob.a{width:520px;height:520px;background:radial-gradient(circle at 30% 30%, rgba(99,91,255,.9), rgba(99,91,255,.2));left:-8%;top:-12%;animation:blobA 26s ease-in-out infinite alternate}
.blob.b{width:460px;height:460px;background:radial-gradient(circle at 30% 30%, rgba(0,214,255,.9), rgba(0,214,255,.2));left:20%;top:10%;animation:blobB 32s ease-in-out infinite alternate}
.blob.c{width:520px;height:520px;background:radial-gradient(circle at 30% 30%, rgba(255,105,97,.9), rgba(255,105,97,.2));right:10%;top:-8%;animation:blobC 28s ease-in-out infinite alternate}
.blob.d{width:420px;height:420px;background:radial-gradient(circle at 30% 30%, rgba(255,214,102,.9), rgba(255,214,102,.2));right:-6%;top:26%;animation:blobD 34s ease-in-out infinite alternate}

@keyframes blobA{0%{transform:translate(-5%, -5%) scale(1) rotate(0)}100%{transform:translate(12%, 6%) scale(1.2) rotate(25deg)}}
@keyframes blobB{0%{transform:translate(0%, 0%) scale(1.1) rotate(0)}100%{transform:translate(8%, -10%) scale(0.9) rotate(-20deg)}}
@keyframes blobC{0%{transform:translate(5%, 0%) scale(1) rotate(0)}100%{transform:translate(-10%, 8%) scale(1.15) rotate(30deg)}}
@keyframes blobD{0%{transform:translate(0, 0) scale(1) rotate(0)}100%{transform:translate(-6%, -8%) scale(1.25) rotate(-15deg)}}

@media (prefers-reduced-motion: reduce){
  .blob{animation:none}
}

/* Beak-inspired stripes overlay */
:root{--beak1:#e61b3b;--beak2:#00d4ff;--beak3:#2ad86b;--beak4:#ffe55c}
.beak-stripes{position:absolute;left:-8%;top:-12%;width:1400px;height:520px;transform:skewY(-8deg) rotate(-8deg);z-index:0;opacity:.9;mix-blend-mode:screen;filter:blur(8px);
  background:linear-gradient(90deg,
    var(--beak1) 0 22%,
    var(--beak2) 22% 44%,
    var(--beak3) 44% 66%,
    var(--beak4) 66% 88%,
    rgba(255,255,255,0) 88% 100%);
  animation:beakDrift 22s ease-in-out infinite alternate}
@keyframes beakDrift{0%{transform:skewY(-8deg) rotate(-8deg) translate3d(0,0,0) scale(1)}100%{transform:skewY(-10deg) rotate(-10deg) translate3d(2%,6%,0) scale(1.05)}}
@media (prefers-reduced-motion: reduce){.beak-stripes{animation:none}}

.hero{position:relative;z-index:1;display:grid;grid-template-columns:1.1fr 0.9fr;gap:40px;align-items:center;padding:72px 0}
.hero h1{font-size:clamp(36px,6vw,72px);line-height:1.05;margin:0;font-weight:800;letter-spacing:-0.02em}
.hero p{font-size:18px;color:var(--muted);max-width:60ch}
.hero .cta{display:flex;gap:10px;flex-wrap:wrap;margin-top:12px}
.mockup-card{position:relative;height:460px;border-radius:20px;border:1px solid rgba(255,255,255,.6);background:rgba(255,255,255,.75);backdrop-filter:blur(6px);box-shadow:0 20px 60px rgba(16,24,40,.18);padding:16px;display:flex;flex-direction:column;gap:12px}
.mockup-card.has-cover{padding:0}
.mockup-cover{position:absolute;inset:0;width:100%;height:100%;object-fit:cover;border-radius:20px}
.mockup-bar{height:10px;border-radius:6px;background:linear-gradient(90deg,#e6e8eb,#f4f6f8)}
.mockup-block{flex:1;border-radius:14px;border:1px solid var(--border);background:linear-gradient(180deg,#fafbfc,#f0f3f7)}

/* Badges/Logos row */
.logos{display:grid;grid-template-columns:repeat(auto-fit,minmax(120px,1fr));gap:20px;align-items:center;opacity:.8}
.logos img{max-width:120px;justify-self:center;filter:grayscale(1)}

/* Auth-state helpers */
.authed-only{display:none}
.anon-only{display:inline}

/* Adobe-style tiles */
.section{padding:40px 0}
.section.lift-up{margin-top:-360px;position:relative;z-index:2}
@media (max-width: 900px){.section.lift-up{margin-top:-180px}}
.feature-grid{display:grid;gap:24px;grid-template-columns:repeat(3,1fr)}
.feature-card{position:relative;border-radius:26px;padding:28px;color:#fff;box-shadow:0 22px 40px rgba(24,39,75,.18), 0 2px 6px rgba(24,39,75,.06);transition:transform .18s ease, box-shadow .18s ease}
.feature-card:hover{transform:translateY(-4px);box-shadow:0 30px 60px rgba(24,39,75,.22), 0 4px 10px rgba(24,39,75,.08)}
.feature-badge{font-size:12px;letter-spacing:.08em;font-weight:800;opacity:.95}
.feature-title{margin:10px 0 6px 0;font-size:24px;font-weight:800}
.feature-desc{margin:0 0 14px 0;font-size:16px;line-height:1.5;color:rgba(255,255,255,.95)}
.feature-cta{display:inline-flex;align-items:center;gap:6px;background:#fff;color:#0a2540;padding:10px 16px;border-radius:999px;font-weight:700;box-shadow:0 6px 16px rgba(0,0,0,.12)}

/* Card gradients to match reference */
.g-quiz{background:linear-gradient(135deg,#7c6cf5 0%, #6b6cf6 35%, #6b50f6 100%)}
.g-flash{background:linear-gradient(135deg,#e84b4b 0%, #f0823c 50%, #e8d254 100%)}
.g-video{background:linear-gradient(135deg,#22d3b6 0%, #3be89b 50%, #34d058 100%)}
.g-guides{background:linear-gradient(135deg,#3b2eb3 0%, #4b36c9 50%, #5a46dc 100%)}
.g-progress{background:linear-gradient(135deg,#4aa1ff 0%, #37d5ff 60%, #18e0e0 100%)}
.g-exam{background:linear-gradient(135deg,#701635 0%, #a2183e 50%, #e0263d 100%)}
.tile.gradient-a p,.tile.gradient-b p,.tile.gradient-c p{color:#f7f9fc}
.tile.gradient-a .mini-cta,.tile.gradient-b .mini-cta,.tile.gradient-c .mini-cta{color:#fff}
.tile.light{background:#ffffff}
.tile .badge{font-size:12px;font-weight:800;letter-spacing:.06em;opacity:.95}
.tile .card-ui{margin-top:12px;background:#fff;border-radius:14px;padding:12px;border:1px solid var(--border)}

/* Quadrant lesson layout */
:root{--mode-read:#00B050;--mode-video:#2DC9F7;--mode-cards:#FFD84D;--mode-quiz:#E53945}
.quad-grid{display:grid;grid-template-columns:1fr 1fr;gap:14px}
@media (max-width: 860px){.quad-grid{grid-template-columns:1fr}}
.quad-card{background:#fff;border:2px solid var(--border);border-radius:16px;padding:16px;box-shadow:var(--shadow)}
.quad-head{display:flex;align-items:center;justify-content:space-between;margin-bottom:8px}
.quad-title{margin:0;font-size:18px;font-weight:800}
.quad-desc{margin:0 0 10px 0}
.quad-cta{display:flex;gap:8px;flex-wrap:wrap;margin-top:10px}
.mode-read{border-color:var(--mode-read)}
.mode-video{border-color:var(--mode-video)}
.mode-cards{border-color:var(--mode-cards)}
.mode-quiz{border-color:var(--mode-quiz)}
.btn.read{background:var(--mode-read);color:#fff}
.btn.video{background:var(--mode-video);color:#0a2540}
.btn.cards{background:var(--mode-cards);color:#0a2540}
.btn.quiz{background:var(--mode-quiz);color:#fff}
/* Ensure meta icon matches mode color */
.mode-quiz .card [aria-hidden="true"]{background:var(--mode-quiz)!important}
/* Outline variant tinted to mode color */
.btn.secondary.quiz{border-color:var(--mode-quiz);color:var(--mode-quiz)}
.btn.secondary.cards{border-color:var(--mode-cards);color:#0a2540}

/* Flashcard flip effect */
.flashcard{position:relative;perspective:1000px;border:none;outline:none;cursor:pointer}
.flashcard:focus{outline:none}
.flashcard .flip-inner{position:relative;width:100%;min-height:220px;transform-style:preserve-3d;transition:transform .5s ease}
.flashcard.flipped .flip-inner{transform:rotateY(180deg)}
.flip-side{backface-visibility:hidden}
.flip-back{position:absolute;inset:0;transform:rotateY(180deg)}
/* Study index card styling */
.face{position:relative;background:#fff;border-radius:14px;padding:18px;border:1px solid #e1e4e8;box-shadow:0 8px 24px rgba(16,24,40,.08)}
.face::before{content:"";position:absolute;left:0;right:0;top:44px;border-top:1px dashed #e9ecf1}
.face-label{font-weight:800;color:#0a2540;margin-bottom:8px}
.face-body{color:#0a0a0a;line-height:1.6}
.flashcard .flip-hint{position:absolute;right:10px;bottom:10px;display:flex;align-items:center;gap:6px;background:rgba(255,255,255,.9);border:1px solid #e6e8eb;border-radius:999px;padding:6px 10px;box-shadow:var(--shadow);transition:opacity .25s ease}
.flashcard:hover .flip-hint{opacity:1}
@media (prefers-reduced-motion: reduce){
  .flashcard .flip-inner{transition:none}
}
/* Accessibility: show a subtle ring on keyboard focus */
.flashcard:focus-visible{box-shadow:0 0 0 3px rgba(99,91,255,.35);border-radius:16px}
@media (prefers-reduced-motion: reduce){
  .flashcard .flip-inner{transition:none}
}

/* Footer (Stripe-like, light) */
.site-footer{position:relative;background:#ffffff;color:#0a0a0a;margin-top:40px}
.site-footer a{color:#0a0a0a;text-decoration:none}
.site-footer .cols{display:grid;gap:20px;grid-template-columns:repeat(auto-fit,minmax(160px,1fr))}
.site-footer h4{margin:0 0 10px 0;color:#0a0a0a}
.site-footer .legal{border-top:1px solid #e6e8eb;margin-top:20px;padding-top:14px;display:flex;justify-content:space-between;flex-wrap:wrap}

/* Pre-footer decorative stripes (match beak hues and sit lower) */
.prefooter-angle{position:relative;height:110px;overflow:hidden;margin-top:40px}
.prefooter-angle::before,.prefooter-angle::after{content:"";position:absolute;left:-5%;width:110%;transform:rotate(-6deg);pointer-events:none}
.prefooter-angle::before{top:58px;height:54px;background:linear-gradient(90deg,#e61b3b, #00d4ff 33%, #2ad86b 66%, #ffe55c);opacity:.9}
.prefooter-angle::after{top:30px;height:28px;background:linear-gradient(90deg,#ff7a3d, #37d5ff 40%, #34d058 75%, #ffd166);opacity:.95}
@media (max-width: 640px){.prefooter-angle{height:90px}.prefooter-angle::before{top:48px;height:44px}.prefooter-angle::after{top:24px;height:22px}}

/* Responsive adjustments */
@media (max-width: 900px){
  .hero{grid-template-columns:1fr; padding:48px 0}
  .hero .mockup-card{order:2;height:280px}
  .adobe-grid{grid-template-columns:repeat(2,1fr)}
}
@media (max-width: 640px){
  .adobe-grid{grid-template-columns:1fr}
  .hero{padding:32px 0}
  .section.lift-up{margin-top:-320px}
  .hero-wrap{min-height:72vh}
  .hero .mockup-card{height:220px}
}

/* Accessible focus styles */
:where(a,button,.btn).focus-visible,:where(a,button,.btn):focus-visible{outline:3px solid #635bff;outline-offset:2px;border-radius:10px}

/* Mobile nav */
@media (max-width: 860px){
  .menu-btn{display:inline-grid}
  .nav-links{display:none;position:absolute;right:24px;top:64px;background:#fff;border:1px solid var(--border);border-radius:14px;box-shadow:var(--shadow-strong);padding:12px;flex-direction:column;gap:10px;z-index:60}
  header.site-header.nav-open .nav-links{display:flex}
}

/* Topic link affordances */
.topic-link{border-radius:8px}
.topic-link:hover,.topic-link:focus-visible{background:#f7f9fc}
.topic-link .topic-title{border-bottom:1px solid transparent}
.topic-link:hover .topic-title,.topic-link:focus-visible .topic-title{border-bottom-color:#0a2540}

/* Feature grid responsive */@media (max-width: 1024px){.feature-grid{grid-template-columns:repeat(2,1fr)}}
@media (max-width: 640px){.feature-grid{grid-template-columns:1fr}.feature-card{padding:22px}.feature-title{font-size:22px}}