:root{--navy:#0d3b82;--navy-2:#08285c;--teal:#11a5a2;--teal-2:#087e7c;--yellow:#ffbf1f;--bg:#f4f7fb;--text:#18324a;--muted:#6a7d90;--line:#dce5ee;--white:#fff;--danger:#dc3545;--success:#16a367;--warning:#f59e0b;--purple:#7c3aed;--shadow:0 18px 50px rgba(15,52,96,.10)}
*{box-sizing:border-box}html{scroll-behavior:smooth}body{margin:0;font-family:Inter,ui-sans-serif,system-ui,-apple-system,BlinkMacSystemFont,"Segoe UI",sans-serif;color:var(--text);background:#fff;line-height:1.55}a{color:inherit;text-decoration:none}img{max-width:100%;display:block}.container{width:min(1160px,calc(100% - 32px));margin:auto}.site-header{position:sticky;top:0;z-index:50;background:rgba(255,255,255,.94);backdrop-filter:blur(16px);border-bottom:1px solid rgba(220,229,238,.8)}.header-inner{min-height:72px;display:flex;align-items:center;gap:30px}.brand{display:inline-flex;align-items:center;gap:10px;font-size:1.18rem;font-weight:800;color:var(--navy)}.brand b{color:var(--teal)}.brand-mark{width:42px;height:42px;border-radius:13px;background:linear-gradient(135deg,var(--navy),#1766c2);display:grid;place-items:center;color:#fff;font-weight:900;box-shadow:0 8px 20px rgba(13,59,130,.25)}.top-nav{display:flex;gap:24px;margin-left:auto}.top-nav a{font-weight:700;color:#486079}.top-nav a:hover{color:var(--navy)}.header-actions{display:flex;gap:10px}.btn{display:inline-flex;align-items:center;justify-content:center;gap:8px;border:0;border-radius:12px;padding:11px 17px;font-weight:800;cursor:pointer;transition:.2s;font-size:.94rem}.btn:hover{transform:translateY(-1px)}.btn-primary{background:linear-gradient(135deg,var(--navy),#1766c2);color:#fff;box-shadow:0 10px 26px rgba(13,59,130,.2)}.btn-teal{background:linear-gradient(135deg,var(--teal),var(--teal-2));color:#fff}.btn-light{background:#eef4fa;color:var(--navy)}.btn-outline{background:#fff;color:var(--navy);border:1px solid #c9d8e6}.btn-danger{background:#fee2e2;color:#991b1b}.btn-sm{padding:8px 12px;border-radius:9px;font-size:.84rem}.btn-block{width:100%}.hero{position:relative;overflow:hidden;background:radial-gradient(circle at 80% 20%,rgba(17,165,162,.18),transparent 28%),linear-gradient(135deg,#f9fcff 0%,#edf6ff 55%,#f9ffff 100%);padding:82px 0}.hero:after{content:"";position:absolute;right:-120px;bottom:-160px;width:420px;height:420px;border-radius:50%;background:rgba(255,191,31,.13)}.hero-grid{display:grid;grid-template-columns:1.03fr .97fr;align-items:center;gap:52px}.eyebrow{display:inline-flex;align-items:center;gap:8px;padding:8px 12px;border-radius:999px;background:#e4f7f6;color:#087e7c;font-weight:800;font-size:.83rem}.hero h1{font-size:clamp(2.6rem,5vw,5rem);line-height:1.02;margin:18px 0 20px;color:var(--navy);letter-spacing:-.045em}.hero h1 span{color:var(--teal)}.hero p{font-size:1.12rem;color:#526b83;max-width:650px}.hero-actions{display:flex;gap:12px;flex-wrap:wrap;margin:28px 0}.hero-points{display:flex;gap:20px;flex-wrap:wrap;color:#38536e;font-weight:700;font-size:.9rem}.hero-card{position:relative;background:#fff;border:1px solid rgba(207,222,236,.85);border-radius:28px;padding:22px;box-shadow:0 30px 80px rgba(13,59,130,.16);transform:rotate(1deg)}.hero-card img{border-radius:18px;width:100%;aspect-ratio:4/5;object-fit:cover}.floating-chip{position:absolute;left:-28px;bottom:30px;background:#fff;border-radius:16px;padding:13px 16px;box-shadow:var(--shadow);font-weight:800;color:var(--navy)}.section{padding:80px 0}.section-soft{background:var(--bg)}.section-title{text-align:center;max-width:760px;margin:0 auto 38px}.section-title h2{font-size:clamp(2rem,4vw,3rem);line-height:1.1;margin:0 0 14px;color:var(--navy);letter-spacing:-.03em}.section-title p{color:var(--muted);font-size:1.05rem}.feature-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:18px}.feature-card{background:#fff;border:1px solid var(--line);border-radius:20px;padding:24px;box-shadow:0 8px 24px rgba(34,70,110,.05)}.feature-card .icon{width:48px;height:48px;border-radius:14px;background:#e8f4ff;display:grid;place-items:center;font-size:1.45rem;margin-bottom:16px}.feature-card h3{margin:0 0 8px;color:var(--navy);font-size:1.05rem}.feature-card p{margin:0;color:var(--muted);font-size:.92rem}.steps{display:grid;grid-template-columns:repeat(4,1fr);gap:20px}.step{position:relative;padding:25px;border-radius:20px;background:#fff;border:1px solid var(--line)}.step-no{width:38px;height:38px;border-radius:50%;background:var(--navy);color:#fff;display:grid;place-items:center;font-weight:900;margin-bottom:14px}.pricing-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(180px,1fr));gap:15px;align-items:stretch}.price-card{background:#fff;border:1px solid var(--line);border-radius:22px;padding:24px;display:flex;flex-direction:column;position:relative}.price-card.featured{border:2px solid var(--yellow);box-shadow:0 18px 55px rgba(255,191,31,.18);transform:translateY(-6px)}.price-card.trial-card{border:2px solid var(--teal);background:linear-gradient(180deg,#f2fffe 0%,#fff 42%);box-shadow:0 18px 50px rgba(17,165,162,.14)}.ribbon{position:absolute;right:14px;top:14px;background:var(--yellow);color:#4c3500;border-radius:999px;padding:5px 9px;font-size:.72rem;font-weight:900}.trial-ribbon{background:var(--teal);color:#fff}.trial-activation{scroll-margin-top:90px;border:2px solid rgba(17,165,162,.35)}.price-card h3{margin:0;color:var(--navy)}.price{font-size:2.1rem;font-weight:900;color:var(--navy);margin:17px 0 4px}.price small{font-size:.8rem;color:var(--muted)}.price-card ul{padding:0;margin:18px 0;list-style:none;flex:1}.price-card li{padding:7px 0;color:#536a80;font-size:.9rem}.price-card li:before{content:"✓";color:var(--teal);font-weight:900;margin-right:8px}.poster-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:20px}.poster-grid img{border-radius:20px;box-shadow:var(--shadow);border:1px solid var(--line)}.cta{background:linear-gradient(135deg,var(--navy-2),var(--navy),var(--teal-2));color:#fff;border-radius:28px;padding:44px;display:flex;align-items:center;justify-content:space-between;gap:24px}.cta h2{margin:0 0 8px;font-size:2rem}.cta p{margin:0;color:#d7e6f4}.site-footer{background:#081d3c;color:#d6e1ec;padding:54px 0 30px}.footer-grid{display:grid;grid-template-columns:2fr 1fr 1fr;gap:40px}.site-footer .brand{color:#fff}.site-footer a{display:block;margin-top:9px;color:#b9c9d8}.site-footer p{color:#b9c9d8}.faq-list{max-width:850px;margin:auto}.faq-item{background:#fff;border:1px solid var(--line);border-radius:16px;padding:20px;margin-bottom:12px}.faq-item h3{margin:0 0 8px;color:var(--navy)}.faq-item p{margin:0;color:var(--muted)}
/* Auth */
.auth-page{min-height:calc(100vh - 72px);display:grid;place-items:center;background:linear-gradient(135deg,#f3f8ff,#effdfb);padding:42px 16px}.auth-card{width:min(520px,100%);background:#fff;border-radius:24px;padding:32px;box-shadow:var(--shadow);border:1px solid var(--line)}.auth-card h1{margin:0 0 8px;color:var(--navy)}.auth-card>p{margin:0 0 24px;color:var(--muted)}.form-grid{display:grid;grid-template-columns:1fr 1fr;gap:16px}.form-group{margin-bottom:16px}.form-group.full{grid-column:1/-1}.form-group label{display:block;margin-bottom:7px;font-weight:800;color:#314c66}.form-control,.form-select,textarea.form-control{width:100%;border:1px solid #cfdbe7;border-radius:12px;padding:12px 13px;font:inherit;background:#fff;color:var(--text);outline:none}.form-control:focus,.form-select:focus{border-color:#5f8fca;box-shadow:0 0 0 3px rgba(23,102,194,.10)}textarea.form-control{min-height:120px;resize:vertical}.help-text{font-size:.82rem;color:var(--muted);margin-top:5px}.auth-footer{text-align:center;margin-top:20px;color:var(--muted)}
/* Dashboard */
.dashboard-body{background:var(--bg)}.app-shell{display:grid;grid-template-columns:260px 1fr;min-height:100vh}.sidebar{background:#071f43;color:#d5e0ea;padding:18px 14px;display:flex;flex-direction:column;position:sticky;top:0;height:100vh;z-index:70}.brand-sidebar{color:#fff;padding:6px 8px 20px}.user-card{display:flex;align-items:center;gap:11px;background:rgba(255,255,255,.07);border:1px solid rgba(255,255,255,.08);border-radius:15px;padding:12px;margin:4px 0 18px}.user-card small{display:block;color:#9fb4ca}.avatar{width:40px;height:40px;border-radius:12px;background:linear-gradient(135deg,var(--teal),#54d1cf);color:#fff;display:grid;place-items:center;font-weight:900}.side-nav{display:flex;flex-direction:column;gap:5px;overflow-y:auto}.nav-item{display:flex;align-items:center;gap:11px;padding:11px 12px;border-radius:10px;color:#b8c8d8;font-weight:700;font-size:.9rem}.nav-item span{min-width:23px;text-align:center}.nav-item:hover,.nav-item.active{background:rgba(255,255,255,.1);color:#fff}.sidebar-footer{margin-top:auto;border-top:1px solid rgba(255,255,255,.1);padding:15px 10px}.sidebar-footer a{color:#ffb7b7}.main-panel{min-width:0}.app-topbar{height:68px;background:#fff;border-bottom:1px solid var(--line);display:flex;align-items:center;justify-content:space-between;padding:0 26px;position:sticky;top:0;z-index:40}.mobile-menu{display:none;border:0;background:#eaf1f8;border-radius:9px;padding:8px;margin-right:10px}.notification-link{position:relative;font-size:1.2rem}.notification-link span{position:absolute;right:-8px;top:-8px;background:var(--danger);color:#fff;border-radius:50%;font-size:.65rem;width:18px;height:18px;display:grid;place-items:center}.page-content{padding:26px}.page-header{display:flex;align-items:flex-start;justify-content:space-between;gap:20px;margin-bottom:22px}.page-header h1{margin:0 0 5px;color:var(--navy);font-size:1.85rem}.page-header p{margin:0;color:var(--muted)}.stats-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:18px;margin-bottom:22px}.stat-card{background:#fff;border:1px solid var(--line);border-radius:18px;padding:20px;box-shadow:0 7px 20px rgba(24,64,105,.04)}.stat-top{display:flex;align-items:center;justify-content:space-between;color:var(--muted);font-size:.88rem;font-weight:700}.stat-icon{width:40px;height:40px;border-radius:12px;background:#eaf4ff;display:grid;place-items:center}.stat-value{font-size:2rem;font-weight:900;color:var(--navy);margin-top:9px}.stat-note{font-size:.8rem;color:var(--muted)}.card{background:#fff;border:1px solid var(--line);border-radius:18px;box-shadow:0 7px 20px rgba(24,64,105,.04)}.card-header{padding:18px 20px;border-bottom:1px solid var(--line);display:flex;align-items:center;justify-content:space-between;gap:15px}.card-header h2,.card-header h3{margin:0;color:var(--navy)}.card-body{padding:20px}.grid-2{display:grid;grid-template-columns:1fr 1fr;gap:20px}.grid-3{display:grid;grid-template-columns:repeat(3,1fr);gap:20px}.table-wrap{overflow-x:auto}.table{width:100%;border-collapse:collapse}.table th,.table td{text-align:left;padding:13px 14px;border-bottom:1px solid #edf1f5;vertical-align:top}.table th{font-size:.78rem;text-transform:uppercase;letter-spacing:.04em;color:#6a7d90;background:#fbfcfe}.table td{font-size:.9rem}.table tr:hover td{background:#fbfdff}.badge{display:inline-flex;align-items:center;border-radius:999px;padding:5px 9px;font-size:.73rem;font-weight:900}.badge-info{background:#dff2ff;color:#08689c}.badge-primary{background:#e3edff;color:#174ea6}.badge-warning{background:#fff0cb;color:#8a5b00}.badge-purple{background:#eee4ff;color:#6431b8}.badge-success{background:#dcfce7;color:#166534}.badge-danger{background:#fee2e2;color:#991b1b}.badge-muted{background:#edf1f5;color:#5e6f80}.alert{padding:13px 15px;border-radius:12px;margin-bottom:18px;font-weight:700}.alert-success{background:#dcfce7;color:#166534}.alert-danger{background:#fee2e2;color:#991b1b}.alert-warning{background:#fff0cb;color:#7c5500}.alert-info{background:#dff2ff;color:#075b8a}.empty{padding:44px 20px;text-align:center;color:var(--muted)}.empty .empty-icon{font-size:2.4rem;margin-bottom:8px}.filter-bar{display:flex;gap:10px;flex-wrap:wrap}.filter-bar .form-control,.filter-bar .form-select{width:auto;min-width:150px}.progress{height:9px;border-radius:999px;background:#e9eef4;overflow:hidden}.progress span{height:100%;display:block;background:linear-gradient(90deg,var(--teal),#5bd4d1)}.quota-box{background:linear-gradient(135deg,#eef8ff,#effcfb);border:1px solid #cfe4f2;border-radius:16px;padding:18px}.quota-box strong{color:var(--navy)}.message-thread{display:flex;flex-direction:column;gap:15px}.message{max-width:78%;padding:13px 15px;border-radius:16px;background:#f0f4f8;border:1px solid #e0e7ee}.message.me{margin-left:auto;background:#dff6ee;border-color:#bcebdc}.message.teacher{background:#e8f0ff;border-color:#ccdafe}.message.system{max-width:100%;text-align:center;background:#fff8db;border-color:#f4e2a0;font-size:.85rem}.message-meta{display:flex;gap:10px;font-size:.74rem;color:#73869a;margin-bottom:5px}.attachment{display:inline-flex;align-items:center;gap:8px;padding:8px 10px;background:#fff;border:1px solid var(--line);border-radius:10px;margin-top:8px;font-size:.83rem}.homework-meta{display:flex;gap:9px;flex-wrap:wrap;margin-top:10px}.meta-pill{background:#eef3f8;border-radius:999px;padding:6px 10px;font-size:.78rem;font-weight:800;color:#4f667c}.timeline{border-left:2px solid #dce5ee;margin-left:8px;padding-left:20px}.timeline-item{position:relative;margin-bottom:18px}.timeline-item:before{content:"";position:absolute;left:-27px;top:5px;width:12px;height:12px;border-radius:50%;background:var(--teal);border:3px solid #fff;box-shadow:0 0 0 1px #b9d8d7}.metric-row{display:grid;grid-template-columns:150px 1fr 80px;gap:12px;align-items:center;margin:12px 0}.stars{display:flex;gap:5px}.stars label{font-size:1.6rem;cursor:pointer}.stars input{display:none}.stars input:checked~label{opacity:.35}.plan-summary{display:flex;align-items:center;justify-content:space-between;gap:20px;padding:20px;background:linear-gradient(135deg,#0d3b82,#0a6d87);color:#fff;border-radius:18px}.plan-summary h3{margin:0 0 5px}.plan-summary p{margin:0;color:#d7e6f4}.mini-list{display:flex;flex-direction:column}.mini-item{display:flex;justify-content:space-between;gap:15px;padding:13px 0;border-bottom:1px solid #edf1f5}.mini-item:last-child{border:0}.muted{color:var(--muted)}.text-danger{color:var(--danger)}.text-success{color:var(--success)}.text-right{text-align:right}.inline-form{display:inline}.w-100{width:100%}.mb-0{margin-bottom:0}.mt-2{margin-top:12px}.mt-3{margin-top:20px}.mb-3{margin-bottom:20px}.code-box{background:#071f43;color:#d7e6f4;border-radius:14px;padding:15px;font-family:ui-monospace,SFMono-Regular,Menlo,monospace;overflow:auto}.marketing-thumb{width:100%;border-radius:14px;border:1px solid var(--line)}
@media(max-width:1100px){.pricing-grid{grid-template-columns:repeat(3,1fr)}.feature-grid{grid-template-columns:repeat(2,1fr)}.stats-grid{grid-template-columns:repeat(2,1fr)}}
@media(max-width:900px){.hero-grid,.grid-2,.grid-3{grid-template-columns:1fr}.hero{padding:55px 0}.hero-card{max-width:560px;margin:auto}.pricing-grid{grid-template-columns:repeat(2,1fr)}.poster-grid{grid-template-columns:repeat(2,1fr)}.top-nav{display:none}.app-shell{grid-template-columns:1fr}.sidebar{position:fixed;left:-280px;width:260px;transition:.25s}.sidebar.open{left:0}.mobile-menu{display:inline-block}.page-content{padding:18px}.cta{flex-direction:column;align-items:flex-start}.steps{grid-template-columns:repeat(2,1fr)}}
@media(max-width:620px){.header-actions .btn-light{display:none}.hero h1{font-size:2.65rem}.feature-grid,.pricing-grid,.poster-grid,.steps,.stats-grid,.form-grid{grid-template-columns:1fr}.footer-grid{grid-template-columns:1fr}.page-header{flex-direction:column}.app-topbar{padding:0 15px}.page-content{padding:14px}.table th,.table td{padding:10px}.message{max-width:92%}.cta{padding:28px}.floating-chip{left:10px}.filter-bar .form-control,.filter-bar .form-select{width:100%}}