/* ===== StudyFlow — Design System ===== */
:root{
  --blue-50:#eef4ff;
  --blue-100:#dbe6ff;
  --blue-500:#3b6cff;
  --blue-600:#2a55e6;
  --blue-700:#1f43c2;
  --purple-300:#c9b8ff;
  --purple-400:#a78bfa;
  --purple-500:#8b6cf2;
  --purple-600:#7553e0;
  --white:#ffffff;
  --bg:#f7f9ff;
  --bg-alt:#eef2ff;
  --text:#0f172a;
  --muted:#5b647a;
  --border:#e6ebf5;
  --radius:16px;
  --radius-lg:24px;
  --shadow-sm:0 4px 14px rgba(31,67,194,.06);
  --shadow:0 10px 30px rgba(31,67,194,.10);
  --shadow-lg:0 24px 60px rgba(31,67,194,.18);
  --grad:linear-gradient(135deg,var(--blue-500),var(--purple-500));
  --grad-soft:linear-gradient(135deg,#eef4ff,#f3edff);
}
*{box-sizing:border-box;margin:0;padding:0}
html,body{overflow-x:hidden;max-width:100%}
html{scroll-behavior:smooth}
body{
  font-family:'Plus Jakarta Sans',system-ui,-apple-system,Segoe UI,Roboto,sans-serif;
  color:var(--text);
  background:var(--bg);
  line-height:1.55;
  -webkit-font-smoothing:antialiased;
}
img{max-width:100%;display:block}
a{color:inherit;text-decoration:none}
.container{width:100%;max-width:1180px;margin:0 auto;padding:0 20px}

/* ===== Buttons ===== */
.btn{display:inline-flex;align-items:center;justify-content:center;gap:8px;padding:12px 20px;border-radius:12px;font-weight:600;font-size:15px;cursor:pointer;border:none;transition:transform .2s ease,box-shadow .2s ease,background .2s ease;font-family:inherit}
.btn-primary{background:var(--grad);color:#fff;box-shadow:0 8px 20px rgba(59,108,255,.35)}
.btn-primary:hover{transform:translateY(-2px);box-shadow:0 12px 28px rgba(59,108,255,.45)}
.btn-ghost{background:transparent;color:var(--text);border:1px solid var(--border)}
.btn-ghost:hover{background:#fff;border-color:var(--blue-500);color:var(--blue-600)}
.btn-lg{padding:15px 26px;font-size:16px;border-radius:14px}

/* ===== Navbar ===== */
.navbar{position:sticky;top:0;z-index:50;background:rgba(255,255,255,.75);backdrop-filter:blur(14px);-webkit-backdrop-filter:blur(14px);border-bottom:1px solid var(--border)}
.nav-inner{display:flex;align-items:center;justify-content:space-between;height:70px;gap:24px}
.brand{display:flex;align-items:center;gap:10px;font-weight:800;font-size:18px}
.brand img{width:32px;height:32px}
.nav-links{display:flex;gap:26px}
.nav-links a{font-weight:500;font-size:15px;color:var(--muted);transition:color .2s}
.nav-links a:hover{color:var(--blue-600)}
.nav-cta{padding:10px 18px;font-size:14px}
.nav-toggle{display:none;flex-direction:column;gap:5px;background:none;border:none;cursor:pointer;padding:8px}
.nav-toggle span{width:24px;height:2px;background:var(--text);border-radius:2px;transition:.3s}

/* ===== Hero ===== */
.hero{position:relative;padding:80px 0 100px;overflow:hidden}
.hero-bg{position:absolute;inset:0;background:radial-gradient(circle at 20% 20%,rgba(139,108,242,.15),transparent 50%),radial-gradient(circle at 80% 30%,rgba(59,108,255,.18),transparent 55%);pointer-events:none;z-index:0}
.hero-inner{position:relative;z-index:1;display:grid;grid-template-columns:1.1fr 1fr;gap:60px;align-items:center}
.pill{display:inline-block;background:#fff;border:1px solid var(--border);padding:6px 14px;border-radius:999px;font-size:13px;font-weight:600;color:var(--blue-600);margin-bottom:20px;box-shadow:var(--shadow-sm)}
.hero h1{font-size:clamp(34px,5vw,58px);line-height:1.08;font-weight:800;letter-spacing:-.02em}
.grad{background:var(--grad);-webkit-background-clip:text;background-clip:text;color:transparent}
.lead{margin-top:18px;font-size:18px;color:var(--muted);max-width:540px}
.hero-cta{display:flex;flex-wrap:wrap;gap:14px;margin-top:30px}
.hero-stats{display:flex;gap:36px;margin-top:42px;flex-wrap:wrap}
.hero-stats strong{display:block;font-size:24px;font-weight:800;color:var(--blue-700)}
.hero-stats span{font-size:13px;color:var(--muted)}
.hero-card{position:relative}
.glass-card{background:rgba(255,255,255,.75);backdrop-filter:blur(20px);border:1px solid rgba(255,255,255,.6);border-radius:var(--radius-lg);padding:24px;box-shadow:var(--shadow-lg)}
.hc-head{display:flex;align-items:center;gap:8px;padding-bottom:14px;border-bottom:1px solid var(--border);margin-bottom:14px;font-size:13px;color:var(--muted);font-weight:600}
.hc-head .dot{width:10px;height:10px;border-radius:50%;background:#dde3f0}
.hc-head .dot:nth-child(1){background:#ff6b6b}.hc-head .dot:nth-child(2){background:#ffd166}.hc-head .dot:nth-child(3){background:#06d6a0}
.hc-head span{margin-left:auto}
.hc-row{display:flex;justify-content:space-between;align-items:center;padding:10px 0;font-size:14px;color:var(--text)}
.tag{display:inline-block;padding:5px 12px;border-radius:999px;font-size:12px;font-weight:600}
.tag-blue{background:var(--blue-50);color:var(--blue-600)}
.tag-purple{background:#f1ebff;color:var(--purple-600)}
.hc-progress{margin-top:14px;padding-top:14px;border-top:1px solid var(--border)}
.hc-progress-label{display:flex;justify-content:space-between;font-size:13px;color:var(--muted);margin-bottom:8px;font-weight:600}
.bar{height:8px;background:var(--bg-alt);border-radius:999px;overflow:hidden}
.bar-fill{height:100%;background:var(--grad);border-radius:999px;transition:width .6s ease}
.float-badge{position:absolute;background:#fff;border-radius:14px;padding:10px 16px;font-size:13px;font-weight:600;box-shadow:var(--shadow);animation:float 4s ease-in-out infinite}
.fb-1{top:-18px;left:-20px}
.fb-2{bottom:-14px;right:-10px;animation-delay:1.5s}
@keyframes float{0%,100%{transform:translateY(0)}50%{transform:translateY(-8px)}}

/* ===== Sections ===== */
.section{padding:90px 0}
.section-alt{background:var(--bg-alt)}
.section-head{text-align:center;max-width:680px;margin:0 auto 50px}
.eyebrow{display:inline-block;text-transform:uppercase;letter-spacing:.12em;font-size:12px;font-weight:700;color:var(--purple-600);margin-bottom:12px}
.section-head h2{font-size:clamp(28px,4vw,40px);font-weight:800;letter-spacing:-.02em;line-height:1.15}
.section-head p{margin-top:14px;color:var(--muted);font-size:17px}

/* ===== Grid + Cards ===== */
.grid{display:grid;gap:24px}
.grid-2{grid-template-columns:repeat(2,1fr)}
.grid-3{grid-template-columns:repeat(3,1fr)}
.grid-4{grid-template-columns:repeat(4,1fr)}
.mt-32{margin-top:32px}
.card,.feature,.testimonial,.stat{background:#fff;border:1px solid var(--border);border-radius:var(--radius);padding:26px;box-shadow:var(--shadow-sm);transition:transform .25s,box-shadow .25s,border-color .25s}
.card:hover,.feature:hover,.testimonial:hover,.stat:hover{transform:translateY(-4px);box-shadow:var(--shadow);border-color:#d6dffb}
.icon-box,.f-icon{width:52px;height:52px;border-radius:14px;background:var(--grad-soft);display:flex;align-items:center;justify-content:center;font-size:24px;margin-bottom:16px}
.card h3,.feature h3{font-size:18px;margin-bottom:8px;font-weight:700}
.card p,.feature p{color:var(--muted);font-size:15px}

/* Steps */
.steps{display:grid;grid-template-columns:repeat(3,1fr);gap:24px}
.step{background:#fff;border:1px solid var(--border);border-radius:var(--radius);padding:30px;text-align:left;position:relative;overflow:hidden}
.step-num{width:44px;height:44px;border-radius:12px;background:var(--grad);color:#fff;display:flex;align-items:center;justify-content:center;font-weight:800;margin-bottom:16px}
.step h3{font-size:18px;margin-bottom:8px}
.step p{color:var(--muted)}

/* Stats */
.stat{text-align:left}
.stat span{display:block;color:var(--muted);font-size:14px;margin-bottom:8px;font-weight:600}
.stat strong{font-size:30px;font-weight:800;background:var(--grad);-webkit-background-clip:text;background-clip:text;color:transparent}

/* Forms */
.schedule-wrap{display:grid;grid-template-columns:340px 1fr;gap:32px;align-items:start}
.schedule-form{background:#fff;border:1px solid var(--border);border-radius:var(--radius);padding:24px;box-shadow:var(--shadow-sm);display:flex;flex-direction:column;gap:14px}
.field{display:flex;flex-direction:column;gap:6px}
.field label{font-size:13px;font-weight:600;color:var(--muted)}
.field input,.field select{padding:11px 14px;border:1px solid var(--border);border-radius:10px;font-size:15px;font-family:inherit;background:#fff;transition:border-color .2s,box-shadow .2s}
.field input:focus,.field select:focus{outline:none;border-color:var(--blue-500);box-shadow:0 0 0 3px rgba(59,108,255,.15)}
.schedule-board{display:grid;grid-template-columns:repeat(auto-fill,minmax(180px,1fr));gap:14px}
.day-col{background:#fff;border:1px solid var(--border);border-radius:var(--radius);padding:16px;min-height:120px}
.day-col h4{font-size:14px;margin-bottom:12px;color:var(--blue-600);font-weight:700;text-transform:uppercase;letter-spacing:.05em}
.task-item{background:var(--grad-soft);border-radius:10px;padding:10px 12px;margin-bottom:8px;font-size:13px;display:flex;justify-content:space-between;align-items:center;gap:8px;border-left:3px solid var(--blue-500)}
.task-item button{background:none;border:none;color:#ff5a5a;cursor:pointer;font-size:16px;line-height:1}
.task-item .meta{display:block;font-size:11px;color:var(--muted);margin-top:2px}

/* Calendar */
.calendar{background:#fff;border:1px solid var(--border);border-radius:var(--radius-lg);padding:28px;box-shadow:var(--shadow-sm)}
.cal-head{display:flex;justify-content:space-between;align-items:center;margin-bottom:16px}
.cal-head h3{font-size:18px;font-weight:700;text-transform:capitalize}
.cal-head button{padding:8px 14px;border-radius:10px;border:1px solid var(--border);background:#fff;cursor:pointer;font-weight:700;color:var(--blue-600)}
.cal-weekdays{display:grid;grid-template-columns:repeat(7,1fr);text-align:center;font-size:12px;font-weight:700;color:var(--muted);margin-bottom:8px;text-transform:uppercase;letter-spacing:.05em}
.cal-grid{display:grid;grid-template-columns:repeat(7,1fr);gap:6px}
.cal-day{aspect-ratio:1;display:flex;align-items:center;justify-content:center;border-radius:10px;font-size:14px;font-weight:600;background:var(--bg);cursor:pointer;transition:all .2s;color:var(--text)}
.cal-day:hover{background:var(--blue-50);color:var(--blue-600)}
.cal-day.today{background:var(--grad);color:#fff;box-shadow:0 6px 14px rgba(59,108,255,.35)}
.cal-day.muted{color:#c0c8d8;background:transparent}
.cal-day.has{position:relative}
.cal-day.has::after{content:"";position:absolute;bottom:6px;width:6px;height:6px;border-radius:50%;background:var(--purple-500)}
.cal-progress{margin-top:24px}
.cal-progress-label{display:flex;justify-content:space-between;margin-bottom:8px;font-size:13px;font-weight:600;color:var(--muted)}

/* Lists */
.inline-form{display:flex;gap:8px;margin:14px 0 16px}
.inline-form input{flex:1;padding:11px 14px;border:1px solid var(--border);border-radius:10px;font-size:14px;font-family:inherit}
.inline-form input:focus{outline:none;border-color:var(--blue-500);box-shadow:0 0 0 3px rgba(59,108,255,.15)}
.list{list-style:none;display:flex;flex-direction:column;gap:8px;max-height:280px;overflow-y:auto}
.list li{display:flex;align-items:center;gap:10px;padding:10px 12px;background:var(--bg);border-radius:10px;font-size:14px}
.list li.done{opacity:.55;text-decoration:line-through}
.list li input[type=checkbox]{width:18px;height:18px;accent-color:var(--blue-500);cursor:pointer}
.list li span{flex:1}
.list li button{background:none;border:none;color:#ff5a5a;cursor:pointer;font-size:16px}

/* Testimonials */
.testimonial p{font-size:15px;color:var(--text);margin-bottom:18px;line-height:1.6}
.author{display:flex;align-items:center;gap:12px}
.avatar{width:44px;height:44px;border-radius:50%;background:var(--grad);color:#fff;display:flex;align-items:center;justify-content:center;font-weight:700;font-size:14px}
.author strong{display:block;font-size:14px}
.author span{font-size:12px;color:var(--muted)}

/* About */
.about-grid{display:grid;grid-template-columns:1fr 1fr;gap:60px;align-items:center}
.checklist{list-style:none;margin-top:20px;display:flex;flex-direction:column;gap:10px}
.checklist li{font-weight:500;color:var(--text)}
.muted{color:var(--muted)}
.about-visual .glass-card{background:#fff}
.about-visual h3{margin-bottom:14px}

/* FAQ */
.faq{max-width:760px;margin:0 auto;display:flex;flex-direction:column;gap:12px}
.faq details{background:#fff;border:1px solid var(--border);border-radius:14px;padding:18px 22px;transition:box-shadow .2s}
.faq details[open]{box-shadow:var(--shadow-sm);border-color:#d6dffb}
.faq summary{cursor:pointer;font-weight:700;font-size:15px;list-style:none;display:flex;justify-content:space-between;align-items:center}
.faq summary::after{content:"+";font-size:22px;color:var(--blue-500);transition:transform .3s;font-weight:400}
.faq details[open] summary::after{transform:rotate(45deg)}
.faq p{margin-top:12px;color:var(--muted);font-size:15px}

/* CTA Final */
.cta-final{padding:90px 0;background:var(--grad);text-align:center;color:#fff}
.cta-final h2{font-size:clamp(28px,4vw,40px);font-weight:800;margin-bottom:14px;letter-spacing:-.02em}
.cta-final p{font-size:17px;opacity:.92;margin-bottom:30px}
.cta-final .btn-primary{background:#fff;color:var(--blue-600);box-shadow:0 14px 30px rgba(0,0,0,.18)}
.cta-final .btn-primary:hover{background:#f5f7ff}

/* Footer */
.footer{background:#0f172a;color:#cbd5e1;padding:60px 0 30px}
.footer .brand{color:#fff;margin-bottom:12px}
.footer-grid{display:grid;grid-template-columns:1.5fr 1fr 1fr 1fr;gap:40px;padding-bottom:40px;border-bottom:1px solid rgba(255,255,255,.08)}
.footer h4{color:#fff;margin-bottom:14px;font-size:14px;font-weight:700;text-transform:uppercase;letter-spacing:.08em}
.footer a{display:block;color:#cbd5e1;font-size:14px;padding:4px 0;transition:color .2s}
.footer a:hover{color:#fff}
.footer-bottom{padding-top:24px;text-align:center;font-size:13px;color:#94a3b8}

/* WhatsApp FAB */
.wa-fab{position:fixed;bottom:24px;right:24px;width:60px;height:60px;border-radius:50%;background:#25d366;display:flex;align-items:center;justify-content:center;box-shadow:0 10px 30px rgba(37,211,102,.4);z-index:60;transition:transform .25s}
.wa-fab:hover{transform:scale(1.08)}
.wa-fab::before{content:"";position:absolute;inset:-6px;border-radius:50%;border:2px solid #25d366;opacity:.5;animation:pulse 2s infinite}
@keyframes pulse{0%{transform:scale(.9);opacity:.6}100%{transform:scale(1.4);opacity:0}}

/* Reveal animations */
.reveal{opacity:0;transform:translateY(24px);transition:opacity .8s ease,transform .8s ease}
.reveal.visible{opacity:1;transform:translateY(0)}

/* ===== Responsive ===== */
@media (max-width: 980px){
  .hero-inner{grid-template-columns:1fr;gap:50px}
  .grid-3,.grid-4,.steps,.about-grid{grid-template-columns:1fr 1fr}
  .schedule-wrap{grid-template-columns:1fr}
  .footer-grid{grid-template-columns:1fr 1fr}
}
@media (max-width: 680px){
  .nav-links{display:none;position:absolute;top:70px;left:0;right:0;background:#fff;flex-direction:column;padding:20px;gap:18px;border-bottom:1px solid var(--border);box-shadow:var(--shadow)}
  .nav-links.open{display:flex}
  .nav-cta{display:none}
  .nav-toggle{display:flex}
  .section{padding:64px 0}
  .hero{padding:50px 0 70px}
  .grid-2,.grid-3,.grid-4,.steps,.about-grid,.footer-grid{grid-template-columns:1fr}
  .hero-stats{gap:24px}
  .float-badge{display:none}
  .cta-final{padding:64px 0}
}