*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
    background: #f1f5f9;
    color: #1e293b;
    line-height: 1.6;
}

.container { max-width: 960px; margin: 0 auto; padding: 2rem 1rem; }

/* Nav */
.topnav {
    background: #1e293b;
    color: #fff;
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0 1.5rem;
    height: 56px;
}
.topnav .brand { color: #fff; text-decoration: none; font-weight: 700; font-size: 1.1rem; }
.topnav ul { list-style: none; display: flex; gap: 1rem; }
.topnav .link { background: none; border: none; color: #94a3b8; cursor: pointer; font-size: .9rem; }
.topnav .link:hover { color: #fff; }

/* Cards */
.card {
    background: #fff;
    border-radius: 8px;
    box-shadow: 0 1px 3px rgba(0,0,0,.1);
    padding: 2rem;
}

/* Auth box */
.auth-box {
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 80vh;
}
.auth-box .card { width: 100%; max-width: 420px; }
.auth-box h1 { margin-bottom: 1.5rem; }

/* Forms */
.form-row { margin-bottom: 1rem; }
.form-row label { display: block; font-weight: 600; margin-bottom: .25rem; font-size: .9rem; }
.form-row input {
    width: 100%;
    padding: .6rem .75rem;
    border: 1px solid #cbd5e1;
    border-radius: 6px;
    font-size: 1rem;
}
.form-row input:focus { outline: none; border-color: #3b82f6; box-shadow: 0 0 0 3px rgba(59,130,246,.15); }

.btn {
    display: inline-block;
    background: #3b82f6;
    color: #fff;
    border: none;
    padding: .65rem 1.5rem;
    border-radius: 6px;
    font-size: 1rem;
    cursor: pointer;
    width: 100%;
    margin-top: .5rem;
}
.btn:hover { background: #2563eb; }

.auth-link { margin-top: 1rem; text-align: center; font-size: .9rem; }
.auth-link a { color: #3b82f6; text-decoration: none; }
.auth-link a:hover { text-decoration: underline; }

/* Alerts */
.alert { padding: .75rem 1rem; border-radius: 6px; margin-bottom: 1rem; font-size: .9rem; }
.alert-success { background: #dcfce7; color: #166534; }
.alert-error { background: #fee2e2; color: #991b1b; }