* { box-sizing: border-box; }
body {
    margin: 0;
    color: #f1f5f9;
    font-family: 'Inter', system-ui, -apple-system, sans-serif;
    line-height: 1.5;
    background:
        radial-gradient(circle at 20% 10%, rgba(99, 102, 241, .18), transparent 42%),
        radial-gradient(circle at 80% 90%, rgba(124, 58, 237, .12), transparent 38%),
        linear-gradient(165deg, #030712 0%, #0f172a 48%, #111827 100%);
}
.login-shell { min-height: 100vh; min-height: 100svh; display: flex; align-items: center; justify-content: center; padding: 40px 16px; }
.login-layout { width: 100%; max-width: 420px; min-width: 0; }
.brand-section { margin-bottom: 40px; text-align: center; }
.brand-identity { display: flex; flex-direction: column; align-items: center; gap: 16px; }
.brand-logo { display: block; height: 56px; width: auto; }
.brand-title { font-size: 28px; font-weight: 600; letter-spacing: -.03em; color: #f8fafc; }
.brand-subtitle { margin-top: 4px; font-size: 15.2px; font-weight: 400; color: #94a3b8; letter-spacing: .08em; }
.platform-name { margin-top: 20px; font-size: 18px; font-weight: 600; letter-spacing: -.02em; color: #e2e8f0; }
.platform-desc { margin-top: 5.6px; font-size: 14px; color: #94a3b8; }
.brand-tagline { margin: 28px 0 0; font-size: clamp(20px, 3.5vw, 28px); font-weight: 300; line-height: 1.35; letter-spacing: -.03em; color: rgba(248, 250, 252, .88); }
.brand-tagline span { background: linear-gradient(90deg, #c7d2fe, #ddd6fe, #e9d5ff); -webkit-background-clip: text; background-clip: text; color: transparent; }
.login-card {
    padding: 32px;
    border-radius: 28px;
    background: rgba(15, 23, 42, .72);
    border: 1px solid rgba(148, 163, 184, .14);
    box-shadow: 0 24px 60px rgba(2, 6, 23, .45), inset 0 1px 0 rgba(255, 255, 255, .04);
    backdrop-filter: blur(16px);
}
.card-heading { margin-bottom: 28px; text-align: center; }
h1 { margin: 0; color: #fff; font-size: 20px; line-height: 28px; font-weight: 600; }
.intro { margin: 8px 0 0; font-size: 14px; color: #94a3b8; }
form { display: grid; gap: 20px; }
label { display: block; margin-bottom: 8px; font-size: 14px; font-weight: 500; color: #cbd5e1; }
input { display: block; width: 100%; min-width: 0; border: 1px solid rgba(100, 116, 139, .45); border-radius: 14px; background: rgba(2, 6, 23, .65); padding: .85rem 1rem; font: inherit; font-size: 14px; color: #f8fafc; outline: none; transition: border-color .2s, box-shadow .2s; }
input::placeholder { color: #64748b; }
input:focus { border-color: rgba(129, 140, 248, .85); box-shadow: 0 0 0 3px rgba(99, 102, 241, .18); }
button { appearance: none; width: 100%; border: 0; border-radius: 14px; padding: .85rem 1rem; font: inherit; font-size: 14px; font-weight: 600; color: #fff; background: linear-gradient(135deg, #6366f1 0%, #7c3aed 100%); cursor: pointer; transition: transform .15s, box-shadow .15s, opacity .15s; }
button:hover { opacity: .95; box-shadow: 0 12px 28px rgba(99, 102, 241, .28); }
button:active { transform: translateY(1px); }
button:focus-visible { outline: 2px solid #a5b4fc; outline-offset: 4px; }
button:disabled { opacity: .55; cursor: wait; box-shadow: none; }
.error { margin: 0; border: 1px solid rgba(244, 63, 94, .3); border-radius: 16px; padding: 12px 16px; font-size: 14px; line-height: 1.5; color: #fecdd3; background: rgba(244, 63, 94, .1); overflow-wrap: anywhere; }
.error:empty { display: none; }
.register-prompt { margin: 24px 0 0; font-size: 14px; text-align: center; color: #94a3b8; }
.register-prompt a { margin-left: 4px; color: #a5b4fc; font-weight: 500; text-decoration: none; }
.register-prompt a:hover { color: #c7d2fe; text-decoration: underline; }
.register-prompt a:focus-visible { outline: 2px solid #a5b4fc; outline-offset: 4px; border-radius: 2px; }
.help { margin: 12px 0 0; font-size: 12px; text-align: center; color: #94a3b8; }
footer { margin-top: 32px; text-align: center; color: #64748b; font-size: 12px; }
@media (min-width: 640px) { .login-shell { padding-inline: 24px; } .login-card { padding: 36px; } }
@media (prefers-reduced-motion: reduce) { input, button { transition: none; } }