/* AI For Students — shared design system */
:root{
  --bg:#fff;--bg-alt:#f9fafb;--bg-dark:#0f172a;--bg-dark-2:#1e293b;
  --blue:#2563eb;--blue-soft:#eff6ff;--lime:#84cc16;--lime-dark:#4d7c0f;--lime-soft:#ecfccb;
  --text:#111827;--text-soft:#374151;--text-muted:#6b7280;--border:#e5e7eb;
  --green:#16a34a;--red:#dc2626;--orange:#ea580c;
  --shadow-sm:0 1px 3px rgba(17,24,39,.06),0 1px 2px rgba(17,24,39,.04);
  --shadow-md:0 8px 24px rgba(17,24,39,.08);
  --shadow-lg:0 20px 50px rgba(17,24,39,.12);
  --shadow-lime:0 16px 40px rgba(132,204,22,.28);
}
*{margin:0;padding:0;box-sizing:border-box}
html{scroll-behavior:smooth}
body{font-family:'Inter',-apple-system,BlinkMacSystemFont,sans-serif;background:var(--bg);color:var(--text-soft);font-size:16px;line-height:1.65;-webkit-font-smoothing:antialiased;-moz-osx-font-smoothing:grayscale;overflow-x:hidden}
h1,h2,h3,h4{font-family:'Space Grotesk',sans-serif;color:var(--text);line-height:1.15;letter-spacing:-0.02em}
a{text-decoration:none;color:inherit}
img,svg{max-width:100%;display:block}
.container{max-width:1180px;margin:0 auto;padding:0 24px}
.container-narrow{max-width:820px;margin:0 auto;padding:0 24px}
.eyebrow{font-family:'Inter',sans-serif;font-size:13px;font-weight:600;color:var(--blue);text-transform:uppercase;letter-spacing:1.5px;margin-bottom:14px}

/* NAVBAR */
.navbar{background:rgba(255,255,255,.8);backdrop-filter:blur(16px);-webkit-backdrop-filter:blur(16px);border-bottom:1px solid var(--border);position:sticky;top:0;z-index:100}
.nav-inner{max-width:1180px;margin:0 auto;padding:16px 24px;display:flex;align-items:center;justify-content:space-between}
.logo{font-family:'Space Grotesk',sans-serif;font-size:20px;font-weight:700;color:var(--text);letter-spacing:-0.4px;display:flex;align-items:center;gap:9px}
.logo-mark{width:30px;height:30px;border-radius:9px;background:linear-gradient(135deg,var(--lime),#65a30d);color:#fff;display:flex;align-items:center;justify-content:center;font-size:17px;font-weight:800;box-shadow:0 4px 10px rgba(132,204,22,.35);font-family:'Space Grotesk',sans-serif}
.nav-links{display:flex;align-items:center;gap:28px;list-style:none}
.nav-links>li>a,.nav-links>li>button{color:var(--text-soft);font-family:'Inter',sans-serif;font-size:14.5px;font-weight:500;background:none;border:none;cursor:pointer;display:flex;align-items:center;gap:4px;padding:6px 0;transition:color .15s}
.nav-links>li>a:hover,.nav-links>li>button:hover{color:var(--text)}
.nav-cta{background:var(--text)!important;color:#fff!important;padding:9px 18px!important;border-radius:10px;font-weight:600!important;transition:transform .15s,background .15s!important}
.nav-cta:hover{transform:translateY(-1px);background:#000!important}
.dropdown{position:relative}
.dropdown-toggle::after{content:'';display:inline-block;width:7px;height:7px;border-right:1.5px solid currentColor;border-bottom:1.5px solid currentColor;transform:rotate(45deg);margin-left:4px;margin-top:-3px;transition:transform .2s}
.dropdown.open .dropdown-toggle::after{transform:rotate(-135deg);margin-top:3px}
.dropdown-menu{position:absolute;top:calc(100% + 14px);right:0;background:var(--bg);border:1px solid var(--border);border-radius:14px;box-shadow:var(--shadow-lg);padding:8px;min-width:460px;opacity:0;visibility:hidden;transform:translateY(-6px);transition:.18s;z-index:200;display:grid;grid-template-columns:1fr 1fr;gap:2px}
.dropdown.open .dropdown-menu{opacity:1;visibility:visible;transform:translateY(0)}
.dropdown-menu a{display:flex;align-items:center;gap:10px;padding:9px 12px;color:var(--text-soft);font-size:14px;font-weight:500;border-radius:9px;transition:background .12s,color .12s}
.dropdown-menu a:hover{background:var(--bg-alt);color:var(--blue)}
.dropdown-menu a img{width:20px;height:20px;border-radius:5px}
.hamburger{display:none;background:none;border:none;cursor:pointer;padding:4px;width:38px;height:38px}
.hamburger span{display:block;width:22px;height:2px;background:var(--text);margin:5px auto;border-radius:2px;transition:.25s}

/* DISCLOSURE */
.disclosure-bar{background:#fefce8;border-bottom:1px solid #fde047;padding:11px 0;font-family:'Inter',sans-serif;font-size:13px;color:#713f12;line-height:1.5}
.disclosure-bar .di{max-width:1180px;margin:0 auto;padding:0 24px}
.disclosure-bar strong{font-weight:600;color:#713f12}

/* BREADCRUMB */
.breadcrumb{padding:24px 0 0;font-family:'Inter',sans-serif;font-size:13px;color:var(--text-muted)}
.breadcrumb a{color:var(--text-muted);transition:color .15s}
.breadcrumb a:hover{color:var(--blue)}
.breadcrumb-sep{margin:0 8px;color:var(--border)}
.breadcrumb-current{color:var(--text);font-weight:500}

/* BUTTONS */
.btn{display:inline-flex;align-items:center;justify-content:center;gap:8px;font-family:'Inter',sans-serif;font-size:15px;font-weight:600;border-radius:12px;padding:14px 26px;cursor:pointer;border:none;transition:transform .15s,box-shadow .15s,background .15s}
.btn-primary{background:linear-gradient(135deg,var(--lime),#65a30d);color:var(--text);box-shadow:var(--shadow-lime)}
.btn-primary:hover{transform:translateY(-2px);box-shadow:0 22px 48px rgba(132,204,22,.4)}
.btn-dark{background:var(--text);color:#fff}
.btn-dark:hover{transform:translateY(-2px);background:#000}
.btn-ghost{background:var(--bg);color:var(--text);border:1px solid var(--border)}
.btn-ghost:hover{transform:translateY(-2px);border-color:var(--text)}

/* HERO (page) */
.page-hero{position:relative;padding:60px 0 64px;overflow:hidden;border-bottom:1px solid var(--border)}
.page-hero-bg{position:absolute;inset:0;z-index:0;pointer-events:none}
.page-hero-bg::before{content:'';position:absolute;top:-220px;right:-160px;width:620px;height:620px;background:radial-gradient(circle,rgba(132,204,22,.14),transparent 65%);border-radius:50%}
.page-hero-bg::after{content:'';position:absolute;bottom:-280px;left:-160px;width:560px;height:560px;background:radial-gradient(circle,rgba(37,99,235,.10),transparent 65%);border-radius:50%}
.page-hero .inner{position:relative;z-index:1;max-width:820px}
.page-hero.center .inner{margin:0 auto;text-align:center}
.tag{display:inline-flex;align-items:center;gap:7px;background:var(--lime-soft);color:var(--lime-dark);padding:7px 15px;border-radius:999px;font-size:13px;font-weight:600;margin-bottom:22px}
.page-hero h1{font-size:clamp(34px,5vw,54px);font-weight:700;color:var(--text);margin-bottom:20px;letter-spacing:-0.03em}
.page-hero .sub{font-family:'Inter',sans-serif;font-size:clamp(17px,2vw,19px);color:var(--text-muted);max-width:680px;line-height:1.6}
.page-hero.center .sub{margin-left:auto;margin-right:auto}
.meta-row{display:flex;gap:18px;flex-wrap:wrap;align-items:center;margin-top:24px;font-family:'Inter',sans-serif;font-size:13.5px;color:var(--text-muted)}
.meta-row .dot{width:4px;height:4px;border-radius:50%;background:var(--border)}

/* SECTIONS */
section{padding:80px 0}
.section-head{text-align:center;max-width:680px;margin:0 auto 56px}
.section-head h2{font-size:clamp(28px,4vw,40px);font-weight:700;margin-bottom:14px}
.section-head p{font-size:17px;color:var(--text-muted);line-height:1.6}

/* ARTICLE BODY */
.article{padding:64px 0}
.article h2{font-size:30px;font-weight:700;margin:48px 0 18px;color:var(--text);scroll-margin-top:90px}
.article h2:first-child{margin-top:0}
.article h3{font-size:22px;font-weight:600;margin:32px 0 14px;color:var(--text)}
.article p{font-family:'Inter',sans-serif;font-size:16.5px;color:var(--text-soft);margin-bottom:18px;line-height:1.78}
.article ul,.article ol{margin:0 0 22px;padding-left:0;list-style:none}
.article ul li{font-family:'Inter',sans-serif;font-size:16px;color:var(--text-soft);padding:9px 0 9px 30px;position:relative;line-height:1.6}
.article ul li::before{content:'';position:absolute;left:8px;top:18px;width:6px;height:6px;border-radius:50%;background:var(--lime)}
.article ol{counter-reset:c}
.article ol li{font-family:'Inter',sans-serif;font-size:16px;color:var(--text-soft);padding:10px 0 10px 40px;position:relative;counter-increment:c;line-height:1.6}
.article ol li::before{content:counter(c);position:absolute;left:0;top:9px;width:26px;height:26px;border-radius:8px;background:var(--lime-soft);color:var(--lime-dark);font-family:'Space Grotesk',sans-serif;font-weight:700;font-size:13px;display:flex;align-items:center;justify-content:center}
.article strong{color:var(--text);font-weight:600}
.article a.ilink{color:var(--blue);font-weight:600;border-bottom:1px solid transparent;transition:border-color .15s}
.article a.ilink:hover{border-bottom-color:var(--blue)}
.article blockquote{border-left:4px solid var(--lime);background:var(--bg-alt);padding:18px 24px;border-radius:0 12px 12px 0;margin:24px 0;font-family:'Space Grotesk',sans-serif;font-size:18px;color:var(--text);font-weight:500}

/* CALLOUT / TIP */
.tip{background:var(--lime-soft);border-left:4px solid var(--lime);border-radius:0 10px 10px 0;padding:18px 22px;margin:24px 0;font-family:'Inter',sans-serif;font-size:15px;color:var(--text-soft)}
.tip strong{color:var(--text)}

/* VERDICT / WINNER BOX */
.verdict{background:var(--bg-dark);color:#fff;border-radius:20px;padding:36px 40px;margin:32px 0;position:relative;overflow:hidden}
.verdict::before{content:'';position:absolute;top:-120px;right:-80px;width:360px;height:360px;background:radial-gradient(circle,rgba(132,204,22,.2),transparent 70%);border-radius:50%}
.verdict .vlabel{position:relative;font-family:'Inter',sans-serif;font-size:12px;font-weight:700;text-transform:uppercase;letter-spacing:1px;color:var(--lime);margin-bottom:10px}
.verdict h3{position:relative;color:#fff;font-size:24px;margin-bottom:12px}
.verdict p{position:relative;font-family:'Inter',sans-serif;color:#cbd5e1;font-size:15.5px;line-height:1.7;margin-bottom:20px}
.verdict .btn-primary{position:relative}

/* TABLE */
.table-wrap{overflow-x:auto;border:1px solid var(--border);border-radius:16px;box-shadow:var(--shadow-sm);margin:28px 0}
table.ctable{width:100%;border-collapse:collapse;min-width:560px;font-family:'Inter',sans-serif}
.ctable th{text-align:left;padding:16px 20px;background:var(--bg-alt);font-size:12.5px;font-weight:700;text-transform:uppercase;letter-spacing:.5px;color:var(--text-soft);border-bottom:1px solid var(--border)}
.ctable td{padding:15px 20px;border-bottom:1px solid var(--border);font-size:14.5px;color:var(--text-soft);vertical-align:top}
.ctable tr:last-child td{border-bottom:none}
.ctable tr:hover td{background:var(--bg-alt)}
.ctable .tool-cell{display:flex;align-items:center;gap:10px;font-weight:600;color:var(--text)}
.ctable .tool-cell img{width:24px;height:24px;border-radius:6px}
.ctable .stars{color:#f59e0b}
.ctable .win{color:var(--lime-dark);font-weight:700}

/* PROS CONS */
.pros-cons{display:grid;grid-template-columns:1fr 1fr;gap:18px;margin:28px 0}
.pc{background:var(--bg);border:1px solid var(--border);border-radius:14px;padding:24px 26px}
.pc.pros{border-top:3px solid var(--green)}
.pc.cons{border-top:3px solid var(--red)}
.pc h4{font-size:16px;margin-bottom:14px;display:flex;align-items:center;gap:8px}
.pc ul{margin:0;padding:0;list-style:none}
.pc li{padding:7px 0 7px 26px;font-size:14.5px;position:relative;line-height:1.55}
.pc.pros li::before{content:'✓';position:absolute;left:0;top:7px;color:var(--green);font-weight:700}
.pc.cons li::before{content:'×';position:absolute;left:2px;top:6px;color:var(--red);font-weight:700;font-size:18px}

/* TOOL CARD GRID */
.tools-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:22px}
.tool-card{background:var(--bg);border:1px solid var(--border);border-radius:18px;padding:26px;display:flex;flex-direction:column;transition:border-color .2s,transform .2s,box-shadow .2s;position:relative}
.tool-card:hover{border-color:var(--lime);transform:translateY(-5px);box-shadow:var(--shadow-md)}
.tool-rank{position:absolute;top:20px;right:22px;font-family:'Space Grotesk',sans-serif;font-size:13px;font-weight:700;color:var(--text-muted);background:var(--bg-alt);border:1px solid var(--border);border-radius:8px;padding:2px 9px}
.tool-head{display:flex;align-items:center;gap:14px;margin-bottom:16px}
.tool-logo{width:52px;height:52px;border-radius:13px;background:var(--bg-alt);border:1px solid var(--border);display:flex;align-items:center;justify-content:center;padding:9px;flex-shrink:0}
.tool-logo img{width:34px;height:34px;object-fit:contain}
.tool-name{font-family:'Space Grotesk',sans-serif;font-size:19px;font-weight:600;color:var(--text)}
.tool-rating{display:flex;align-items:center;gap:6px;margin-top:3px}
.tool-rating .stars{color:#f59e0b;font-size:13px;letter-spacing:.5px}
.tool-rating .num{font-size:12.5px;font-weight:600;color:var(--text-muted)}
.tool-desc{font-family:'Inter',sans-serif;font-size:14.5px;color:var(--text-muted);line-height:1.6;margin-bottom:18px;flex-grow:1}
.tool-foot{display:flex;align-items:center;justify-content:space-between;padding-top:16px;border-top:1px solid var(--border)}
.badge{font-family:'Inter',sans-serif;font-size:12px;font-weight:600}
.badge-free{color:var(--green)}.badge-freemium{color:var(--blue)}.badge-paid{color:var(--orange)}
.tool-link{font-family:'Inter',sans-serif;font-size:13.5px;font-weight:600;color:var(--text);display:inline-flex;align-items:center;gap:4px;transition:gap .2s,color .2s}
.tool-card:hover .tool-link{gap:8px;color:var(--lime-dark)}

/* BLOG CARDS */
.post-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:26px}
.post-card{background:var(--bg);border:1px solid var(--border);border-radius:18px;overflow:hidden;display:flex;flex-direction:column;transition:transform .2s,box-shadow .2s,border-color .2s}
.post-card:hover{transform:translateY(-5px);box-shadow:var(--shadow-md);border-color:var(--lime)}
.post-thumb{aspect-ratio:16/9;background:var(--bg-alt);border-bottom:1px solid var(--border);display:flex;align-items:center;justify-content:center;position:relative;overflow:hidden}
.post-thumb svg{width:100%;height:100%}
.post-cat{position:absolute;top:14px;left:14px;background:rgba(255,255,255,.92);backdrop-filter:blur(6px);color:var(--text);font-family:'Inter',sans-serif;font-size:11.5px;font-weight:700;text-transform:uppercase;letter-spacing:.5px;padding:5px 11px;border-radius:999px;box-shadow:var(--shadow-sm)}
.post-body{padding:24px;display:flex;flex-direction:column;flex-grow:1}
.post-body h3{font-size:19px;font-weight:600;line-height:1.3;margin-bottom:10px}
.post-body p{font-family:'Inter',sans-serif;font-size:14px;color:var(--text-muted);line-height:1.6;margin-bottom:16px;flex-grow:1}
.post-meta{display:flex;align-items:center;gap:8px;font-family:'Inter',sans-serif;font-size:12.5px;color:var(--text-muted)}
.post-read{font-family:'Inter',sans-serif;font-size:13.5px;font-weight:600;color:var(--lime-dark);margin-top:14px;display:inline-flex;gap:4px;transition:gap .2s}
.post-card:hover .post-read{gap:8px}

/* TOC */
.toc{background:var(--bg-alt);border:1px solid var(--border);border-radius:14px;padding:22px 26px;margin:0 0 32px}
.toc h4{font-size:13px;text-transform:uppercase;letter-spacing:.8px;color:var(--text-muted);margin-bottom:12px;font-family:'Inter',sans-serif;font-weight:700}
.toc ol{list-style:none;counter-reset:t;padding:0;margin:0}
.toc ol li{counter-increment:t;margin-bottom:8px;padding:0}
.toc ol li::before{content:none;display:none}
.toc a{font-family:'Inter',sans-serif;font-size:14.5px;color:var(--text-soft);display:flex;gap:10px;transition:color .15s}
.toc a::before{content:counter(t);color:var(--lime-dark);font-weight:700;font-family:'Space Grotesk',sans-serif}
.toc a:hover{color:var(--blue)}

/* FORM */
.form-card{background:var(--bg);border:1px solid var(--border);border-radius:18px;padding:36px;box-shadow:var(--shadow-sm)}
.field{margin-bottom:20px}
.field label{display:block;font-family:'Inter',sans-serif;font-size:14px;font-weight:600;color:var(--text);margin-bottom:7px}
.field input,.field textarea{width:100%;padding:13px 16px;border:1px solid var(--border);border-radius:11px;font-family:'Inter',sans-serif;font-size:15px;color:var(--text);outline:none;transition:border-color .2s;background:var(--bg)}
.field input:focus,.field textarea:focus{border-color:var(--lime)}
.field textarea{min-height:140px;resize:vertical}
.form-success{display:none;background:var(--lime-soft);border:1px solid #d9f99d;border-radius:12px;padding:18px 20px;font-family:'Inter',sans-serif;font-size:15px;color:var(--lime-dark);font-weight:600}
.form-success.show{display:block}

/* CTA STRIP */
.cta-strip{background:var(--bg-alt);border-top:1px solid var(--border);border-bottom:1px solid var(--border)}
.cta-box{max-width:880px;margin:0 auto;background:linear-gradient(135deg,var(--lime),#4d7c0f);border-radius:28px;padding:52px 50px;text-align:center;position:relative;overflow:hidden}
.cta-box::before{content:'';position:absolute;top:-120px;left:-80px;width:360px;height:360px;background:radial-gradient(circle,rgba(255,255,255,.18),transparent 70%);border-radius:50%}
.cta-box h2{position:relative;color:var(--text);font-size:clamp(26px,4vw,38px);margin-bottom:14px}
.cta-box p{position:relative;font-family:'Inter',sans-serif;font-size:16px;color:#1a2e05;margin-bottom:28px;max-width:520px;margin-left:auto;margin-right:auto}
.cta-box .btn-dark{position:relative}

/* RELATED */
.related-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:22px}

/* FOOTER */
.footer{background:var(--bg-dark);color:#cbd5e1;padding:70px 0 32px}
.footer-grid{display:grid;grid-template-columns:1.6fr 1fr 1fr 1fr;gap:48px;margin-bottom:50px}
.footer-brand .logo{color:#fff;margin-bottom:16px}
.footer-brand p{font-family:'Inter',sans-serif;font-size:14px;color:#94a3b8;max-width:300px;line-height:1.7;margin-bottom:22px}
.social-links{display:flex;gap:10px}
.social-link{width:38px;height:38px;border-radius:10px;background:rgba(255,255,255,.06);display:flex;align-items:center;justify-content:center;color:#cbd5e1;transition:background .2s,transform .2s,color .2s}
.social-link:hover{background:var(--lime);color:var(--text);transform:translateY(-2px)}
.social-link svg{width:17px;height:17px}
.footer-col h4{font-family:'Space Grotesk',sans-serif;font-size:15px;font-weight:600;color:#fff;margin-bottom:18px}
.footer-col ul{list-style:none}
.footer-col li{margin-bottom:11px}
.footer-col a{font-family:'Inter',sans-serif;font-size:14px;color:#94a3b8;transition:color .15s}
.footer-col a:hover{color:var(--lime)}
.footer-bottom{padding-top:30px;border-top:1px solid rgba(255,255,255,.08);display:flex;justify-content:space-between;align-items:center;gap:16px;flex-wrap:wrap;font-family:'Inter',sans-serif;font-size:13px;color:#64748b}
.footer-tagline{color:#94a3b8;font-weight:500}

/* REVEAL */
.reveal{opacity:0;transform:translateY(28px);transition:opacity .7s ease,transform .7s ease}
.reveal.in{opacity:1;transform:translateY(0)}

/* RESPONSIVE */
@media(max-width:980px){
  .tools-grid,.post-grid,.related-grid{grid-template-columns:repeat(2,1fr)}
  .footer-grid{grid-template-columns:1fr 1fr;gap:36px}
  .footer-brand{grid-column:1/-1}
  .dropdown-menu{min-width:360px}
  .verdict{padding:30px 28px}
}
@media(max-width:680px){
  section{padding:56px 0}
  .article{padding:48px 0}
  .nav-links{position:fixed;inset:69px 0 auto 0;background:var(--bg);border-bottom:1px solid var(--border);flex-direction:column;align-items:stretch;gap:0;padding:12px 0 20px;display:none;box-shadow:var(--shadow-md)}
  .nav-links.open{display:flex}
  .nav-links>li{width:100%}
  .nav-links>li>a,.nav-links>li>button{padding:13px 24px;width:100%;justify-content:flex-start}
  .nav-cta{margin:6px 24px!important;justify-content:center!important}
  .dropdown-menu{position:static;opacity:1;visibility:visible;transform:none;box-shadow:none;border:none;grid-template-columns:1fr;min-width:0;max-height:0;overflow:hidden;padding:0 12px;transition:max-height .3s}
  .dropdown.open .dropdown-menu{max-height:900px;padding:6px 12px}
  .hamburger{display:block}
  .tools-grid,.post-grid,.related-grid,.pros-cons,.footer-grid{grid-template-columns:1fr}
  .cta-box{padding:40px 26px}
  .verdict{padding:28px 22px}
}