:root { --bg-color: #0f172a; --card-bg: #1e293b; --accent: #38bdf8; --text-main: #f1f5f9; --border: #334155; }
        body { font-family: system-ui, sans-serif; background-color: var(--bg-color); color: var(--text-main); display: flex; justify-content: center; align-items: center; height: 100vh; margin: 0; }
        .login-card { background: var(--card-bg); padding: 2.5rem; border-radius: 12px; width: 100%; max-width: 400px; border: 1px solid var(--border); }
        .header { text-align: center; margin-bottom: 2rem; }
        .logo-icon { width: 48px; height: 48px; background: var(--accent); margin: 0 auto 1rem; border-radius: 10px; }
        .form-group { margin-bottom: 1.5rem; }
        input { width: 100%; padding: 12px; border-radius: 8px; border: 1px solid var(--border); background: var(--bg-color); color: white; box-sizing: border-box; }
        .btn { width: 100%; padding: 12px; border: none; border-radius: 8px; background: var(--accent); color: #0f172a; font-weight: 700; cursor: pointer; }