:root { 
    --primary: #1a237e; 
    --secondary: #2e7d32; 
    --bg: #f4f7f6; 
    --card: #ffffff; 
    --text-main: #1c1c1c; 
    --text-muted: #757575; 
    --radius: 18px; 
    --border: rgba(0,0,0,0.08); 
}
* { margin: 0; padding: 0; box-sizing: border-box; }
body { font-family: 'Inter', sans-serif; background-color: var(--bg); color: var(--text-main); line-height: 1.5; transition: 0.3s; }
body.dark-mode { --bg: #121212; --card: #1e1e1e; --text-main: #f0f0f0; --text-muted: #aaa; --border: rgba(255,255,255,0.1); }

main { max-width: 680px; margin: 40px auto; padding: 0 20px; min-height: 80vh; }
.collab-card { background: var(--card); padding: 35px; border-radius: var(--radius); box-shadow: 0 4px 20px rgba(0,0,0,0.05); border: 1px solid var(--border); }
.collab-header { text-align: center; margin-bottom: 25px; }
.collab-header h1 { color: var(--primary); font-size: 1.8rem; font-weight: 800; margin-bottom: 10px; }
body.dark-mode .collab-header h1 { color: #fff; }
.collab-header p { color: var(--text-muted); font-size: 0.95rem; max-width: 520px; margin: 0 auto; }

.intro-box { background: rgba(26, 35, 126, 0.03); border: 1px solid var(--border); border-radius: 12px; padding: 16px 20px; margin-bottom: 30px; font-size: 0.88rem; color: var(--text-muted); text-align: center; }
body.dark-mode .intro-box { background: rgba(255,255,255,0.02); }

.form-group { margin-bottom: 20px; }
.form-group label { display: block; font-size: 12px; font-weight: 700; color: var(--text-main); margin-bottom: 8px; text-transform: uppercase; letter-spacing: 0.5px; }

.form-control { width: 100%; padding: 12px 15px; border-radius: 10px; border: 1.5px solid var(--border); background: var(--bg); color: var(--text-main); font-family: 'Inter', sans-serif; font-size: 15px; transition: 0.3s; }
.form-control:focus { outline: none; border-color: var(--secondary); box-shadow: 0 0 0 3px rgba(46, 125, 50, 0.1); }

.btn-send { width: 100%; padding: 14px; background-color: var(--secondary); color: #fff; border: none; border-radius: 10px; font-size: 15px; font-weight: 700; cursor: pointer; transition: 0.3s; display: flex; align-items: center; justify-content: center; gap: 10px; margin-top: 10px; }
.btn-send:hover { opacity: 0.9; transform: translateY(-1px); }
.btn-send:disabled { opacity: 0.6; cursor: not-allowed; }

.status-msg { margin-top: 15px; padding: 12px; border-radius: 8px; font-size: 0.9rem; text-align: center; display: none; }
.status-msg.success { background: rgba(46, 125, 50, 0.1); color: var(--secondary); border: 1px solid var(--secondary); }
.status-msg.error { background: rgba(211, 47, 47, 0.1); color: #d32f2f; border: 1px solid #d32f2f; }

.form-row { display: grid; grid-template-columns: 1fr 1fr; gap: 15px; }
@media (max-width: 600px) { .form-row { grid-template-columns: 1fr; } .collab-card { padding: 22px; } }