@import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700&display=swap');
:root{--primary-color:#3b82f6;--primary-hover:#2563eb;--primary-light:#dbeafe;--secondary-color:#8b5cf6;--success-color:#10b981;--success-light:#d1fae5;--warning-color:#f59e0b;--warning-light:#fef3c7;--danger-color:#ef4444;--danger-light:#fecaca;--bg-light:#ffffff;--bg-secondary:#f8fafc;--bg-tertiary:#f1f5f9;--text-primary:#0f172a;--text-secondary:#475569;--text-muted:#64748b;--border-color:#e2e8f0;--border-hover:#cbd5e1;--shadow-sm:0 1px 2px 0 rgba(0,0,0,0.05);--shadow-md:0 4px 6px -1px rgba(0,0,0,0.1);--shadow-lg:0 10px 15px -3px rgba(0,0,0,0.1);--shadow-xl:0 20px 25px -5px rgba(0,0,0,0.1);--radius-sm:6px;--radius-md:8px;--radius-lg:12px;--radius-xl:16px;}
.dark{--bg-light:#0f172a;--bg-secondary:#1e293b;--bg-tertiary:#334155;--text-primary:#f1f5f9;--text-secondary:#cbd5e1;--text-muted:#94a3b8;--border-color:#334155;--border-hover:#475569;--primary-light:#1e3a8a;--success-light:#064e3b;--warning-light:#92400e;--danger-light:#991b1b;}
*{margin:0;padding:0;box-sizing:border-box;}
body{font-family:'Inter',-apple-system,BlinkMacSystemFont,'Segoe UI',Roboto,sans-serif;background:var(--bg-secondary);color:var(--text-primary);line-height:1.6;transition:all 0.3s ease;min-height:100vh;}
.header{background:var(--bg-light);border-bottom:1px solid var(--border-color);padding:1rem 0;position:sticky;top:0;z-index:100;backdrop-filter:blur(10px);}
.header-content{max-width:1200px;margin:0 auto;display:flex;justify-content:space-between;align-items:center;padding:0 1.5rem;}
.logo{display:flex;align-items:center;gap:0.5rem;font-size:1.5rem;font-weight:700;color:var(--primary-color);text-decoration:none;}
.logo-icon{width:32px;height:32px;background:linear-gradient(135deg,var(--primary-color),var(--secondary-color));border-radius:var(--radius-md);display:flex;align-items:center;justify-content:center;color:white;font-size:1.2rem;}
.logo img{width:180px;height:auto;object-fit:contain;}
.theme-toggle{display:flex;align-items:center;gap:0.75rem;font-size:0.9rem;color:var(--text-secondary);}
.theme-switch{position:relative;width:44px;height:24px;}
.theme-switch input{opacity:0;width:0;height:0;}
.slider{position:absolute;cursor:pointer;top:0;left:0;right:0;bottom:0;background-color:var(--border-color);transition:0.3s;border-radius:24px;}
.slider:before{position:absolute;content:"";height:18px;width:18px;left:3px;bottom:3px;background-color:white;transition:0.3s;border-radius:50%;}
input:checked+.slider{background-color:var(--primary-color);}
input:checked+.slider:before{transform:translateX(20px);}
.main-container{max-width:1200px;margin:0 auto;padding:0 1.5rem;}
.hero-section{padding:4rem 0 6rem;text-align:center;}
.hero-title{font-size:3.5rem;font-weight:700;margin-bottom:1.5rem;background:linear-gradient(135deg,var(--primary-color),var(--secondary-color));-webkit-background-clip:text;-webkit-text-fill-color:transparent;background-clip:text;line-height:1.1;}
.hero-subtitle{font-size:1.25rem;color:var(--text-secondary);margin-bottom:3rem;max-width:600px;margin-left:auto;margin-right:auto;}
.main-card{background:var(--bg-light);border-radius:var(--radius-xl);box-shadow:var(--shadow-xl);border:1px solid var(--border-color);padding:2.5rem;margin-bottom:3rem;transition:all 0.3s ease;}
.main-card:hover{box-shadow:0 25px 50px -12px rgba(0,0,0,0.15);transform:translateY(-2px);}
.main-card-policy{text-align:left!important;background:var(--bg-light);border-radius:var(--radius-xl);box-shadow:var(--shadow-xl);border:1px solid var(--border-color);padding:2.5rem;margin-bottom:3rem;transition:all 0.3s ease;}
.main-card-policy ul{padding-left:20px;}
.main-card-policy h2{margin:15px 0px;}
.main-card-policy:hover{box-shadow:0 25px 50px -12px rgba(0,0,0,0.15);transform:translateY(-2px);}
.form-group{margin-bottom:1.5rem;}
.form-label{display:block;font-weight:600;margin-bottom:0.5rem;color:var(--text-primary);}
.form-textarea{width:100%;min-height:200px;padding:1rem;border:2px solid var(--border-color);border-radius:var(--radius-lg);background:var(--bg-light);color:var(--text-primary);font-size:1rem;font-family:inherit;resize:vertical;transition:all 0.3s ease;}
.form-textarea:focus{outline:none;border-color:var(--primary-color);box-shadow:0 0 0 3px var(--primary-light);}
.form-textarea::placeholder{color:var(--text-muted);}
.btn{display:inline-flex;align-items:center;justify-content:center;gap:0.5rem;padding:0.875rem 2rem;border:none;border-radius:var(--radius-lg);font-size:1rem;font-weight:600;cursor:pointer;transition:all 0.3s ease;text-decoration:none;font-family:inherit;}
.btn-primary{background:linear-gradient(135deg,var(--primary-color),var(--secondary-color));color:white;box-shadow:var(--shadow-md);}
.btn-primary:hover{transform:translateY(-1px);box-shadow:var(--shadow-lg);}
.btn-primary:active{transform:translateY(0);}
.btn-large{padding:1rem 2.5rem;font-size:1.1rem;}
.turnstile-container{display:flex;justify-content:center;margin:1.5rem 0;}
.features-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(280px,1fr));gap:2rem;margin-top:4rem;}
.feature-card{display: flex;flex-flow: column;justify-content: center;align-items: center;background:var(--bg-light);padding:2rem;border-radius:var(--radius-lg);border:1px solid var(--border-color);transition:all 0.3s ease;}
.feature-card:hover{transform:translateY(-4px);box-shadow:var(--shadow-lg);}
.feature-icon{width:48px;height:48px;background:linear-gradient(135deg,var(--primary-color),var(--secondary-color));border-radius:var(--radius-lg);display:flex;align-items:center;justify-content:center;color:white;font-size:1.5rem;margin-bottom:1rem;}
.feature-title{font-size:1.25rem;font-weight:600;margin-bottom:0.75rem;color:var(--text-primary);}
.feature-description{color:var(--text-secondary);line-height:1.6;}
.result-container{margin-top:2rem;}
.result-card{background:var(--bg-light);border-radius:var(--radius-lg);padding:2rem;border:1px solid var(--border-color);margin-bottom:1rem;}
.result-header{display:flex;align-items:center;gap:1rem;margin-bottom:1.5rem;}
.result-icon{width:48px;height:48px;border-radius:50%;display:flex;align-items:center;justify-content:center;font-size:1.5rem;}
.result-ai .result-icon{background:var(--danger-light);color:var(--danger-color);}
.result-human .result-icon{background:var(--success-light);color:var(--success-color);}
.result-title{font-size:1.5rem;font-weight:700;margin:0;}
.result-ai .result-title{color:var(--danger-color);}
.result-human .result-title{color:var(--success-color);}
.score-container{display:grid;grid-template-columns:1fr 1fr;gap:1rem;margin-bottom:1.5rem;}
.score-item{text-align:center;padding:1rem;background:var(--bg-secondary);border-radius:var(--radius-md);}
.score-label{font-size:0.875rem;color:var(--text-muted);margin-bottom:0.25rem;}
.score-value{font-size:1.5rem;font-weight:700;color:var(--text-primary);}
.back-link{display:inline-flex;align-items:center;gap:0.5rem;color:var(--primary-color);text-decoration:none;font-weight:600;}
.back-link:hover{text-decoration:underline;}
.error{background:var(--danger-light);color:var(--danger-color);padding:1rem;border-radius:var(--radius-md);border:1px solid var(--danger-color);margin-bottom:1rem;text-align:center;}
.footer{background:var(--bg-light);border-top:1px solid var(--border-color);padding:2rem 0;margin-top:4rem;}
.footer-content{max-width:1200px;margin:0 auto;padding:0 1.5rem;text-align:center;color:var(--text-muted);}
@media(max-width:768px){
    .hero-title{font-size:2.5rem;}
    .hero-subtitle{font-size:1.1rem;}
    .main-card{padding:1.5rem;}
    .features-grid{grid-template-columns:1fr;}
    .score-container{grid-template-columns:1fr;}
    .header-content,.main-container,.footer-content{padding:0 1rem;}
}


.theme-toggle{display:flex;align-items:center;gap:0.75rem;font-size:0.9rem;color:var(--text-secondary);}
.theme-switch{position:relative;width:44px;height:24px;display:inline-block;}
.theme-switch input{opacity:0;width:0;height:0;}
.slider{position:absolute;cursor:pointer;top:0;left:0;right:0;bottom:0;background-color:var(--border-color);transition:0.3s;border-radius:24px;}
.slider:before{position:absolute;content:"";height:18px;width:18px;left:3px;bottom:3px;background-color:white;transition:0.3s;border-radius:50%;}
input:checked + .slider{background-color:var(--primary-color);}
input:checked + .slider:before{transform:translateX(20px);}
body.dark{--bg-light:#0f172a;--bg-secondary:#1e293b;--bg-tertiary:#334155;--text-primary:#f1f5f9;--text-secondary:#cbd5e1;--text-muted:#94a3b8;--border-color:#334155;--border-hover:#475569;--primary-light:#1e3a8a;--success-light:#064e3b;--warning-light:#92400e;--danger-light:#991b1b;}


.ai-model-switch{position:relative;display:inline-block;width:44px;height:24px;}
.ai-model-switch input{opacity:0;width:0;height:0;}
.ai-model-slider{position:absolute;cursor:pointer;top:0;left:0;right:0;bottom:0;background-color:var(--border-color);transition:0.3s;border-radius:24px;}
.ai-model-slider:before{position:absolute;content:"";height:18px;width:18px;left:3px;bottom:3px;background-color:white;transition:0.3s;border-radius:50%;}
input:checked+.ai-model-slider{background-color:var(--primary-color);}
input:checked+.ai-model-slider:before{transform:translateX(20px);}

.textarea-wrapper {
  position: relative;
}

.textarea-overlay {
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: rgba(255, 255, 255, 0.7);
  border-radius: var(--radius-lg);
  display: flex;
  justify-content: center;
  align-items: center;
  z-index: 2;
}

.spinner {
  display: inline-block;
  width: 20px;
  height: 20px;
  border: 3px solid rgba(255, 255, 255, 0.3);
  border-radius: 50%;
  border-top-color: white;
  animation: spin 1s ease-in-out infinite;
  vertical-align: middle;
  margin-right: 8px;
}
@keyframes spin {
  to { transform: rotate(360deg); }
}