* { margin: 0; padding: 0; box-sizing: border-box; font-family: 'Poppins', sans-serif; }
body { background: linear-gradient(135deg, #667eea, #764ba2); color: #fff; padding: 20px; }
.container { max-width: 500px; margin: auto; background: rgba(255,255,255,0.1); padding: 25px; border-radius: 20px; backdrop-filter: blur(10px); }
h1 { text-align: center; margin-bottom: 5px; }
.subtitle { text-align: center; opacity: 0.8; margin-bottom: 20px; font-size: 14px; }
.subject-row { display: flex; gap: 8px; margin-bottom: 10px; }
input, select { padding: 10px; border-radius: 10px; border: none; width: 100%; }
button { width: 100%; padding: 12px; margin-top: 10px; border: none; border-radius: 10px; background: #fff; color: #667eea; font-weight: bold; cursor: pointer; }
button.calc { background: #ffd700; color: #000; }
#result { margin-top: 20px; padding: 15px; background: rgba(0,0,0,0.3); border-radius: 10px; text-align: center; font-size: 20px; }
.target-box { margin-top: 20px; padding: 15px; background: rgba(255,255,255,0.15); border-radius: 10px; }