:root {
  --primary: #1e293b;
  --accent: #2563eb;
  --bg: #f8fafc;
  --surface: #ffffff;
  --text: #334155;
  --text-light: #64748b;
  --border: #e2e8f0;
  --radius: 8px;
}

* { box-sizing: border-box; margin: 0; padding: 0; }
body { font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif; background: var(--bg); color: var(--text); line-height: 1.6; }

/* Header & Nav */
header { background: var(--surface); border-bottom: 1px solid var(--border); padding: 1rem 5%; display: flex; justify-content: space-between; align-items: center; }
.logo { font-size: 1.25rem; font-weight: 700; color: var(--primary); text-decoration: none; }
nav a { color: var(--text-light); text-decoration: none; margin-left: 1.5rem; font-weight: 500; transition: color 0.2s; }
nav a:hover, nav a.active { color: var(--accent); }

/* Main Container */
main { max-width: 900px; margin: 3rem auto; padding: 0 1.5rem; }
.card { background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius); padding: 2.5rem; box-shadow: 0 4px 6px -1px rgba(0,0,0,0.05); }

/* Typography */
h1 { font-size: 2.25rem; color: var(--primary); margin-bottom: 1rem; }
p { color: var(--text-light); margin-bottom: 1.5rem; }

/* Form Controls */
.form-group { margin-bottom: 1.25rem; }
label { display: block; font-weight: 600; margin-bottom: 0.5rem; color: var(--primary); }
input[type="text"], input[type="email"], textarea, input[type="file"] {
  width: 100%; padding: 0.75rem; border: 1px solid var(--border); border-radius: var(--radius); font-size: 1rem;
}
textarea { resize: vertical; min-height: 120px; }
button { background: var(--accent); color: white; border: none; padding: 0.75rem 1.5rem; border-radius: var(--radius); font-size: 1rem; font-weight: 600; cursor: pointer; }
button:hover { opacity: 0.9; }

/* Footer */
footer { text-align: center; padding: 2rem; color: var(--text-light); font-size: 0.875rem; margin-top: auto; }