:root {
    --primary: #1687d9;
    --primary-dark: #0869ae;
    --background: #f5f7fa;
    --surface: #ffffff;
    --text: #17202a;
    --muted: #74808c;
    --border: #e4e9ee;
    --danger: #dc4d4d;
    --shadow: 0 20px 60px rgba(18, 35, 52, .12);
}

* { box-sizing: border-box; }

body {
    margin: 0;
    min-height: 100vh;
    font-family: Inter, -apple-system, BlinkMacSystemFont, "Segoe UI", Arial, sans-serif;
    background: radial-gradient(circle at top, #ffffff 0, var(--background) 55%, #edf1f5 100%);
    color: var(--text);
}

.login-shell {
    min-height: 100vh;
    display: grid;
    place-items: center;
    padding: 24px;
}

.login-card {
    width: min(430px, 100%);
    background: var(--surface);
    border: 1px solid rgba(228,233,238,.9);
    border-radius: 22px;
    padding: 38px;
    box-shadow: var(--shadow);
}

.brand { display: flex; align-items: center; gap: 13px; margin-bottom: 42px; }
.brand-mark {
    width: 48px; height: 48px; border-radius: 13px;
    display: grid; place-items: center;
    background: #0d1722; color: white; font-size: 23px; font-weight: 700;
}
.brand strong { display: block; font-size: 21px; letter-spacing: .04em; }
.brand span { display: block; margin-top: 2px; font-size: 10px; letter-spacing: .16em; color: var(--muted); }
.eyebrow { font-size: 11px; font-weight: 700; letter-spacing: .13em; color: var(--primary); }
h1 { margin: 8px 0 8px; font-size: 31px; letter-spacing: -.03em; }
.intro { margin: 0 0 28px; color: var(--muted); line-height: 1.55; }

form { display: grid; gap: 9px; }
label { font-size: 13px; font-weight: 600; margin-top: 7px; }
input {
    width: 100%; height: 48px; border: 1px solid var(--border); border-radius: 11px;
    padding: 0 14px; outline: none; background: #fff; color: var(--text); font-size: 15px;
    transition: border-color .15s, box-shadow .15s;
}
input:focus { border-color: var(--primary); box-shadow: 0 0 0 3px rgba(22,135,217,.12); }
.password-wrap { position: relative; }
.password-wrap input { padding-right: 80px; }
.show-password {
    position: absolute; right: 8px; top: 7px; height: 34px; padding: 0 9px;
    border: 0; background: transparent; color: var(--primary-dark); font-weight: 600; cursor: pointer;
}
.login-button {
    height: 48px; margin-top: 16px; border: 0; border-radius: 11px;
    background: var(--primary); color: white; font-weight: 700; cursor: pointer;
    transition: transform .1s, background .15s;
}
.login-button:hover { background: var(--primary-dark); }
.login-button:active { transform: translateY(1px); }
.login-button:disabled { opacity: .65; cursor: wait; }
.message { min-height: 20px; margin: 8px 0 0; color: var(--danger); font-size: 13px; line-height: 1.4; }
small { color: var(--muted); line-height: 1.4; }
footer { margin-top: 28px; text-align: center; color: var(--muted); font-size: 11px; }

@media (max-width: 480px) {
    .login-shell { padding: 14px; }
    .login-card { padding: 28px 22px; border-radius: 18px; }
    .brand { margin-bottom: 32px; }
}