*{margin:0;padding:0;box-sizing:border-box}
:root{
  --primary:#ff6b35;--primary-light:#fff0e8;--primary-dark:#e55a25;
  --surface:#ffffff;--surface-dim:#f2f2f7;--surface-container:#f7f7fc;--surface-high:#eeeef4;
  --on-surface:#1c1b1f;--on-surface-var:#49454f;--outline:#79747e;--outline-var:#cac4d0;
  --secondary:#625b71;--tertiary:#7d5260;
  --success:#2e7d32;--success-bg:#e8f5e9;
  --info:#1565c0;--info-bg:#e3f2fd;
  --shadow-sm:0 1px 3px rgba(0,0,0,.08),0 1px 2px rgba(0,0,0,.06);
  --shadow-md:0 4px 12px rgba(0,0,0,.08),0 2px 4px rgba(0,0,0,.04);
  --shadow-lg:0 8px 24px rgba(0,0,0,.1),0 4px 8px rgba(0,0,0,.06);
  --radius:12px;--radius-sm:8px;--radius-lg:16px;--radius-xl:24px;
}
body{font-family:'Inter',system-ui,-apple-system,sans-serif;background:var(--surface-dim);color:var(--on-surface);line-height:1.6;-webkit-font-smoothing:antialiased}
a{color:var(--primary);text-decoration:none}a:hover{text-decoration:underline}

/* Nav */
#nav{background:var(--surface);border-bottom:1px solid var(--outline-var);position:sticky;top:0;z-index:100;backdrop-filter:blur(12px)}
.nav-inner{max-width:1100px;margin:0 auto;padding:12px 24px;display:flex;align-items:center;justify-content:space-between}
.logo{font-size:20px;font-weight:700;color:var(--on-surface);display:flex;align-items:center;gap:6px}
.logo span{color:var(--primary)}.logo:hover{text-decoration:none}
.nav-links{display:flex;align-items:center;gap:8px;font-size:14px}
.nav-links>a{color:var(--on-surface-var);padding:8px 14px;border-radius:20px;transition:all .2s}
.nav-links>a:hover,.nav-links>a.active{background:var(--surface-dim);color:var(--on-surface);text-decoration:none}

/* Buttons */
.btn{display:inline-flex;align-items:center;gap:6px;padding:8px 20px;border-radius:20px;font-size:14px;font-weight:500;cursor:pointer;border:none;transition:all .2s;text-decoration:none}
.btn:hover{text-decoration:none;transform:translateY(-1px)}
.btn-primary{background:var(--primary);color:#fff;box-shadow:var(--shadow-sm)}.btn-primary:hover{background:var(--primary-dark);box-shadow:var(--shadow-md)}
.btn-tonal{background:var(--primary-light);color:var(--primary)}.btn-tonal:hover{background:#ffe0cc}
.btn-outline{background:transparent;border:1px solid var(--outline-var);color:var(--on-surface)}.btn-outline:hover{border-color:var(--primary);color:var(--primary)}
.btn-text{background:transparent;color:var(--primary);padding:8px 12px}.btn-text:hover{background:var(--primary-light)}
.btn-lg{padding:12px 28px;font-size:16px;border-radius:24px}
.btn-sm{padding:4px 14px;font-size:12px}
.btn-danger{background:#ffebee;color:#c62828}.btn-danger:hover{background:#ffcdd2}
.btn-success{background:var(--success-bg);color:var(--success)}.btn-success:hover{background:#c8e6c9}

/* Hero */
.hero{text-align:center;padding:80px 24px 60px;background:linear-gradient(180deg,var(--surface) 0%,var(--surface-dim) 100%)}
.hero h1{font-size:48px;font-weight:800;color:var(--on-surface);line-height:1.15;margin-bottom:16px;letter-spacing:-.02em}
.accent{color:var(--primary)}
.hero-sub{font-size:18px;color:var(--on-surface-var);margin-bottom:36px;max-width:560px;margin-left:auto;margin-right:auto}
.hero-actions{display:flex;gap:12px;justify-content:center;margin-bottom:48px}
.hero-stats{display:flex;gap:40px;justify-content:center}
.hero-stats .stat{text-align:center}
.hero-stats .stat b{display:block;font-size:28px;font-weight:700;color:var(--primary)}
.hero-stats .stat span{font-size:13px;color:var(--on-surface-var)}

/* Sections */
.section{max-width:1100px;margin:0 auto;padding:64px 24px}
.section-full{max-width:100%;background:var(--surface);padding:64px 24px}
.section-title{text-align:center;font-size:28px;font-weight:700;color:var(--on-surface);margin-bottom:12px}
.section-sub{text-align:center;color:var(--on-surface-var);margin-bottom:48px;font-size:16px}

/* Steps */
.steps{display:grid;grid-template-columns:repeat(4,1fr);gap:24px}
.step{text-align:center;padding:24px 16px}
.step-num{width:44px;height:44px;border-radius:50%;background:var(--primary);color:#fff;display:inline-flex;align-items:center;justify-content:center;font-weight:700;font-size:18px;margin-bottom:16px;box-shadow:var(--shadow-sm)}
.step h3{color:var(--on-surface);margin-bottom:8px;font-size:15px}.step p{color:var(--on-surface-var);font-size:13px}

/* Features */
.features{display:grid;grid-template-columns:repeat(4,1fr);gap:20px;max-width:1100px;margin:0 auto}
.feature{background:var(--surface);border:1px solid var(--outline-var);border-radius:var(--radius-lg);padding:28px 20px;text-align:center;transition:all .2s;box-shadow:var(--shadow-sm)}
.feature:hover{box-shadow:var(--shadow-md);transform:translateY(-2px)}
.feature-icon{font-size:36px;margin-bottom:14px}
.feature h3{color:var(--on-surface);margin-bottom:8px;font-size:15px}.feature p{color:var(--on-surface-var);font-size:13px}

/* Cards — neumorphic blog style */
.card{background:var(--surface);border-radius:var(--radius-lg);padding:20px 24px;margin-bottom:16px;cursor:pointer;transition:all .25s;box-shadow:var(--shadow-sm);border:1px solid transparent}
.card:hover{box-shadow:var(--shadow-lg);border-color:var(--primary-light);transform:translateY(-2px)}
.card-title{font-size:17px;font-weight:600;color:var(--on-surface);margin-bottom:6px;display:flex;align-items:center;gap:10px}
.card .meta{font-size:12px;color:var(--on-surface-var);display:flex;align-items:center;gap:14px;margin-bottom:10px;flex-wrap:wrap}
.card .desc{font-size:14px;color:var(--on-surface-var);display:-webkit-box;-webkit-line-clamp:2;-webkit-box-orient:vertical;overflow:hidden}
.card-footer{display:flex;align-items:center;gap:12px;margin-top:12px;padding-top:12px;border-top:1px solid var(--surface-high);font-size:12px;color:var(--on-surface-var)}
.tag{display:inline-block;background:var(--primary-light);color:var(--primary);padding:2px 10px;border-radius:20px;font-size:11px;font-weight:500;margin-right:4px}
.status{display:inline-flex;align-items:center;gap:4px;padding:3px 12px;border-radius:20px;font-size:11px;font-weight:600;white-space:nowrap}
.status.open{background:var(--success-bg);color:var(--success)}.status.solved{background:var(--info-bg);color:var(--info)}

/* Forms — neumorphic */
.form-page{max-width:440px;margin:48px auto;padding:0 24px}
.form-page h2{color:var(--on-surface);margin-bottom:6px;font-size:24px}.form-page .sub{color:var(--on-surface-var);margin-bottom:24px;font-size:14px}
.form-box{background:var(--surface);border-radius:var(--radius-lg);padding:28px;box-shadow:var(--shadow-md)}
.form-group{margin-bottom:18px}
.form-group label{display:block;font-size:13px;font-weight:500;color:var(--on-surface);margin-bottom:6px}
.form-group input{width:100%;background:var(--surface-dim);border:1px solid var(--outline-var);color:var(--on-surface);padding:12px 14px;border-radius:var(--radius-sm);font-size:14px;transition:all .2s}
.form-group input:focus{outline:none;border-color:var(--primary);box-shadow:0 0 0 3px var(--primary-light)}
.form-row{display:flex;gap:8px}.form-row input{flex:1}
.form-error{color:#c62828;font-size:13px;margin-top:10px;display:none;padding:8px 12px;background:#ffebee;border-radius:var(--radius-sm)}
.form-success{color:var(--success);font-size:13px;margin-top:10px;display:none;padding:8px 12px;background:var(--success-bg);border-radius:var(--radius-sm)}

/* Container */
.container{max-width:1100px;margin:0 auto;padding:24px}
.page-header{display:flex;align-items:center;justify-content:space-between;margin-bottom:24px;flex-wrap:wrap;gap:12px}
.page-header h2{color:var(--on-surface);font-size:22px}

/* Search */
.search-bar{display:flex;gap:8px;margin-bottom:24px;flex-wrap:wrap}
.search-bar input,.search-bar select{background:var(--surface);border:1px solid var(--outline-var);color:var(--on-surface);padding:10px 14px;border-radius:var(--radius-sm);font-size:14px;transition:border-color .2s}
.search-bar input{flex:1;min-width:200px}
.search-bar input:focus,.search-bar select:focus{outline:none;border-color:var(--primary)}

/* Modal — detail page style */
.modal-bg{display:none;position:fixed;inset:0;background:rgba(0,0,0,.3);z-index:200;justify-content:center;align-items:flex-start;padding:32px 16px;overflow-y:auto;backdrop-filter:blur(4px)}
.modal-bg.show{display:flex}
.modal{background:var(--surface);border-radius:var(--radius-xl);width:90%;max-width:800px;max-height:85vh;overflow-y:auto;padding:32px;box-shadow:var(--shadow-lg)}
.modal h2{color:var(--on-surface);margin-bottom:6px;font-size:22px;display:flex;align-items:center;gap:10px}
.modal .close{float:right;cursor:pointer;color:var(--on-surface-var);font-size:24px;width:36px;height:36px;display:flex;align-items:center;justify-content:center;border-radius:50%;transition:background .2s}
.modal .close:hover{background:var(--surface-dim)}

/* Solutions — thread style */
.solutions-section{margin-top:28px;border-top:1px solid var(--outline-var);padding-top:20px}
.solutions-section h3{font-size:16px;color:var(--on-surface);margin-bottom:16px;display:flex;align-items:center;gap:8px}
.solution{background:var(--surface-container);border-radius:var(--radius);padding:16px 20px;margin-bottom:12px;border-left:3px solid var(--outline-var);transition:all .2s}
.solution:hover{box-shadow:var(--shadow-sm)}
.solution.accepted{border-left-color:var(--success);background:var(--success-bg)}
.solution h4{color:var(--on-surface);font-size:15px;margin-bottom:4px;display:flex;align-items:center;gap:8px}
.badge{background:var(--success-bg);color:var(--success);padding:2px 10px;border-radius:20px;font-size:11px;font-weight:600}
.votes{font-size:12px;color:var(--on-surface-var);display:flex;align-items:center;gap:4px}

/* Dashboard */
.dash-grid{display:grid;grid-template-columns:260px 1fr;gap:24px;align-items:start}
.dash-sidebar{background:var(--surface);border-radius:var(--radius-lg);padding:8px;box-shadow:var(--shadow-sm)}
.dash-menu-item{display:flex;align-items:center;gap:10px;padding:12px 16px;border-radius:var(--radius-sm);cursor:pointer;font-size:14px;color:var(--on-surface-var);transition:all .2s}
.dash-menu-item:hover{background:var(--surface-dim);color:var(--on-surface)}
.dash-menu-item.active{background:var(--primary-light);color:var(--primary);font-weight:600}
.dash-panel{background:var(--surface);border-radius:var(--radius-lg);padding:28px;box-shadow:var(--shadow-sm);min-height:400px}
.dash-panel h3{font-size:18px;color:var(--on-surface);margin-bottom:6px}
.dash-panel .panel-sub{color:var(--on-surface-var);font-size:14px;margin-bottom:20px}
.apikey-box{background:var(--surface-dim);border:1px solid var(--outline-var);border-radius:var(--radius-sm);padding:14px;font-family:'JetBrains Mono',monospace;font-size:13px;word-break:break-all;color:var(--primary);margin-bottom:14px}
.code-block{background:var(--surface-dim);border:1px solid var(--outline-var);border-radius:var(--radius-sm);padding:16px;font-family:'JetBrains Mono',monospace;font-size:13px;overflow-x:auto;margin:12px 0;color:var(--on-surface);white-space:pre;line-height:1.5}

/* Skill page */
.skill-hero{text-align:center;padding:60px 24px 32px;background:var(--surface)}
.skill-hero h1{font-size:32px;color:var(--on-surface);margin-bottom:10px}
.download-box{background:var(--surface);border:1px solid var(--outline-var);border-radius:var(--radius-lg);padding:36px;text-align:center;max-width:600px;margin:0 auto;box-shadow:var(--shadow-md)}
.setup-card{background:var(--surface);border:1px solid var(--outline-var);border-radius:var(--radius);padding:24px;margin-bottom:16px;box-shadow:var(--shadow-sm)}
.setup-card h3{font-size:15px;color:var(--on-surface);margin-bottom:8px}

/* Footer */
footer{text-align:center;padding:40px 24px;color:var(--on-surface-var);font-size:13px;background:var(--surface);border-top:1px solid var(--outline-var)}
footer a{color:var(--on-surface-var)}footer a:hover{color:var(--primary)}
footer p+p{margin-top:6px}

.empty{text-align:center;padding:48px;color:var(--on-surface-var);font-size:15px}

/* Problem detail description */
.problem-desc{margin:16px 0;padding:20px;background:var(--surface-container);border-radius:var(--radius);white-space:pre-wrap;font-size:14px;line-height:1.7;color:var(--on-surface)}

@media(max-width:768px){
  .steps,.features{grid-template-columns:1fr 1fr}
  .dash-grid{grid-template-columns:1fr}
  .hero h1{font-size:32px}
  .nav-links{gap:4px;font-size:13px}
}
@media(max-width:480px){.steps,.features{grid-template-columns:1fr}}
.wizard-step{padding:20px 0;border-bottom:1px solid var(--surface-high)}
.wizard-step:last-of-type{border-bottom:none}
.wizard-step h4{font-size:15px;color:var(--primary);margin-bottom:6px}