:root {
    /* Neutral Palette */
    --cream: #FAF8F5;
    --beige: #F0EAE1;
    --taupe: #D1CCB9;
    --mocha: #3B332B;
    --dark-mocha: #231E19;
    --white: #FFFFFF;
    
    --font-heading: 'Plus Jakarta Sans', sans-serif;
    --font-body: 'Plus Jakarta Sans', sans-serif;
    --font-code: 'Source Code Pro', monospace;
}

* { margin: 0; padding: 0; box-sizing: border-box; cursor: none; }

body { background-color: var(--cream); color: var(--mocha); font-family: var(--font-body); overflow-x: hidden; }

/* Custom Cursor */
.cosmos-cursor {
    position: fixed; width: 24px; height: 24px; border: 1px solid var(--mocha); border-radius: 50%;
    pointer-events: none; z-index: 10000; transform: translate(-50%, -50%); transition: width 0.2s, height 0.2s, background 0.2s;
}
.cosmos-cursor::after {
    content: ''; position: absolute; top: 50%; left: 50%; width: 4px; height: 4px; background: var(--mocha); border-radius: 50%; transform: translate(-50%, -50%);
}
.cosmos-cursor.hover { width: 48px; height: 48px; background: rgba(59, 51, 43, 0.1); }

/* Navigation */
.cosmos-nav {
    position: fixed; top: 0; width: 100%; padding: 20px 5%; display: flex; justify-content: space-between; align-items: center; z-index: 100; background: rgba(250, 248, 245, 0.9); backdrop-filter: blur(8px); border-bottom: 1px solid var(--beige);
}
.logo { font-weight: 700; font-size: 1.2rem; letter-spacing: 1px; color: var(--dark-mocha); }
.nav-links a { margin: 0 20px; text-decoration: none; color: var(--mocha); font-weight: 500; font-size: 0.9rem; transition: color 0.3s; }
.nav-links a:hover { color: var(--dark-mocha); }
.user-actions { display: flex; align-items: center; gap: 20px; }
.user-actions span { font-weight: 600; font-size: 0.9rem; }

.btn-primary { background: var(--dark-mocha); color: var(--white); border: none; padding: 10px 24px; border-radius: 30px; font-weight: 600; font-size: 0.9rem; transition: transform 0.2s, background 0.2s; }
.btn-primary:hover { transform: translateY(-2px); background: var(--mocha); }

/* Hero */
.cosmos-hero { height: 100vh; display: flex; align-items: center; justify-content: center; position: relative; }
#cosmos-canvas { position: absolute; inset: 0; z-index: 1; }
.hero-content { position: relative; z-index: 2; text-align: center; max-width: 800px; padding: 0 20px; }
.hero-content h1 { font-size: 4rem; font-weight: 700; color: var(--dark-mocha); margin-bottom: 40px; line-height: 1.1; }

.search-wrap { display: flex; background: var(--white); border-radius: 50px; padding: 8px; box-shadow: 0 10px 30px rgba(59, 51, 43, 0.1); border: 1px solid var(--beige); }
.search-wrap input { flex: 1; border: none; background: transparent; padding: 0 20px; font-family: var(--font-body); font-size: 1rem; color: var(--mocha); outline: none; }
.search-btn { background: var(--taupe); color: var(--dark-mocha); border: none; padding: 12px 30px; border-radius: 40px; font-weight: 600; transition: background 0.2s; }
.search-btn:hover { background: var(--mocha); color: var(--white); }

/* How It Works */
.how-it-works { padding: 100px 5%; background: var(--white); border-bottom: 1px solid var(--beige); }
.steps-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 40px; max-width: 1200px; margin: 0 auto; }
.step-card { background: var(--cream); padding: 40px; border-radius: 16px; border: 1px solid var(--beige); transition: transform 0.4s cubic-bezier(0.175, 0.885, 0.32, 1.275); }
.step-card:hover { transform: translateY(-10px); border-color: var(--taupe); }
.step-num { font-size: 3rem; font-weight: 700; color: var(--taupe); margin-bottom: 20px; font-family: var(--font-heading); }
.step-card h3 { font-size: 1.5rem; margin-bottom: 15px; color: var(--dark-mocha); }
.step-card p { color: var(--mocha); line-height: 1.6; }

/* Explorer Globe */
.subject-explorer { padding: 120px 5%; display: flex; align-items: center; justify-content: space-between; max-width: 1400px; margin: 0 auto; }
.explorer-text { flex: 1; padding-right: 50px; }
.explorer-text h2 { font-size: 3rem; color: var(--dark-mocha); margin-bottom: 20px; }
.explorer-text p { font-size: 1.1rem; line-height: 1.8; color: var(--mocha); }
.globe-container { flex: 1; height: 500px; position: relative; display: flex; justify-content: center; align-items: center; }
#globe-canvas { width: 100%; height: 100%; cursor: grab; }
#globe-canvas:active { cursor: grabbing; }
.globe-tooltip { position: absolute; background: var(--white); padding: 10px 15px; border-radius: 8px; box-shadow: 0 4px 12px rgba(0,0,0,0.1); border: 1px solid var(--beige); font-weight: 600; display: none; pointer-events: none; }
.globe-tooltip span { font-weight: 400; font-size: 0.8rem; color: var(--taupe); }

/* Interactive Demo */
.interactive-demo { padding: 100px 5%; background: var(--dark-mocha); color: var(--white); }
.demo-header { text-align: center; margin-bottom: 60px; }
.demo-header h2 { font-size: 2.5rem; margin-bottom: 10px; }
.demo-header p { color: var(--taupe); }
.editor-layout { display: flex; max-width: 1200px; margin: 0 auto; gap: 30px; background: var(--mocha); border-radius: 16px; overflow: hidden; border: 1px solid #4a4237; }
.lesson-panel { flex: 1; padding: 40px; background: #332b24; }
.badge { display: inline-block; background: var(--taupe); color: var(--dark-mocha); font-size: 0.7rem; font-weight: 700; padding: 4px 10px; border-radius: 4px; margin-bottom: 20px; }
.lesson-panel h3 { font-size: 1.5rem; margin-bottom: 15px; }
.lesson-panel p { color: var(--beige); margin-bottom: 20px; line-height: 1.6; }
.lesson-panel code { background: rgba(0,0,0,0.2); padding: 2px 6px; border-radius: 4px; font-family: var(--font-code); }
.hint { padding: 15px; border-left: 3px solid var(--taupe); background: rgba(209, 204, 185, 0.1); font-size: 0.9rem; }

.code-panel { flex: 1.5; display: flex; flex-direction: column; }
.panel-header { display: flex; justify-content: space-between; align-items: center; padding: 15px 20px; background: #261f1a; border-bottom: 1px solid #4a4237; }
.panel-header span { font-family: var(--font-code); color: var(--taupe); font-size: 0.9rem; }
#run-btn { background: var(--taupe); color: var(--dark-mocha); border: none; padding: 6px 15px; border-radius: 4px; font-weight: 600; font-size: 0.8rem; }
.code-area { display: flex; flex: 1; background: #1e1915; }
.line-numbers { padding: 20px 10px; color: #5a5247; font-family: var(--font-code); font-size: 0.9rem; text-align: right; user-select: none; border-right: 1px solid #332b24; }
#code-input { flex: 1; background: transparent; border: none; color: var(--white); font-family: var(--font-code); font-size: 0.9rem; padding: 20px; outline: none; resize: none; line-height: 1.5; }
.console-output { height: 100px; background: #000; color: #00ff00; font-family: var(--font-code); padding: 15px; font-size: 0.85rem; overflow-y: auto; }

/* Courses Grid */
.featured-courses { padding: 100px 5%; background: var(--cream); }
.section-title { text-align: center; font-size: 2.5rem; color: var(--dark-mocha); margin-bottom: 60px; }
.course-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 30px; max-width: 1400px; margin: 0 auto; }
.course-card { background: var(--white); border-radius: 12px; overflow: hidden; border: 1px solid var(--beige); transition: transform 0.3s, box-shadow 0.3s; }
.course-card:hover { transform: translateY(-5px); box-shadow: 0 10px 20px rgba(59, 51, 43, 0.05); }
.course-thumb { height: 160px; width: 100%; position: relative; }
/* Simulated 3D isometric pattern overlay in CSS */
.course-thumb::after { content: ''; position: absolute; inset: 0; background-image: linear-gradient(30deg, rgba(255,255,255,0.2) 12%, transparent 12.5%, transparent 87%, rgba(255,255,255,0.2) 87.5%, rgba(255,255,255,0.2)), linear-gradient(150deg, rgba(255,255,255,0.2) 12%, transparent 12.5%, transparent 87%, rgba(255,255,255,0.2) 87.5%, rgba(255,255,255,0.2)); background-size: 20px 35px; }
.course-info { padding: 20px; }
.course-info .tag { font-size: 0.7rem; font-weight: 700; color: var(--taupe); display: block; margin-bottom: 10px; }
.course-info h3 { font-size: 1.1rem; color: var(--dark-mocha); margin-bottom: 5px; line-height: 1.4; }
.course-info p { font-size: 0.85rem; color: var(--mocha); margin-bottom: 15px; }
.course-meta { display: flex; justify-content: space-between; font-size: 0.8rem; color: var(--taupe); font-weight: 600; border-top: 1px solid var(--beige); padding-top: 15px; }

/* Footer */
.cosmos-footer { background: var(--white); padding: 60px 5%; border-top: 1px solid var(--beige); }
.footer-wrap { display: flex; justify-content: space-between; max-width: 1200px; margin: 0 auto; }
.f-col h3 { color: var(--dark-mocha); margin-bottom: 10px; font-size: 1.2rem; }
.f-col p { color: var(--mocha); font-size: 0.9rem; }
.f-col a { display: block; color: var(--mocha); text-decoration: none; margin-bottom: 10px; font-size: 0.9rem; }
.f-col a:hover { color: var(--dark-mocha); }

@media (max-width: 900px) {
    .steps-grid { grid-template-columns: 1fr; }
    .subject-explorer { flex-direction: column; }
    .editor-layout { flex-direction: column; }
    .course-grid { grid-template-columns: 1fr 1fr; }
}