:root {
  color-scheme: light;
  --ink: #16181b;
  --muted: #6d727a;
  --paper: #f4f5f1;
  --line: #e3e5e1;
  --accent: #c8ff3d;
  --accent-dark: #95c400;
  --danger: #b42318;
  --shadow: 0 18px 45px rgb(24 28 18 / .07);
}

* { box-sizing: border-box; }

body {
  min-height: 100vh;
  margin: 0;
  background:
    radial-gradient(circle at 15% 15%, rgb(200 255 61 / .18), transparent 28rem),
    var(--paper);
  color: var(--ink);
  font-family: Inter, "Pretendard", "Noto Sans KR", system-ui, sans-serif;
}

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

.login-card {
  width: min(100%, 440px);
  padding: 40px;
  border: 1px solid var(--line);
  border-radius: 20px;
  background: #fff;
  box-shadow: var(--shadow);
}

.brand-mark {
  width: 50px;
  height: 50px;
  display: grid;
  place-items: center;
  margin-bottom: 24px;
  border-radius: 15px;
  background: var(--ink);
  color: var(--accent);
  font-size: 23px;
  font-weight: 900;
  letter-spacing: -.08em;
  box-shadow: 0 9px 22px rgb(22 24 27 / .18);
}

.eyebrow {
  margin: 0 0 8px;
  color: #747b6a;
  font: 800 11px/1.3 ui-monospace, Consolas, monospace;
  letter-spacing: .13em;
}

h1 {
  margin: 0 0 10px;
  font-size: clamp(28px, 8vw, 44px);
  line-height: 1.05;
  letter-spacing: -.05em;
}

.description {
  margin: 0 0 30px;
  color: var(--muted);
  font-size: 14px;
  line-height: 1.6;
}

form { display: grid; gap: 9px; }

label {
  margin-top: 7px;
  color: #555b63;
  font-size: 12px;
  font-weight: 750;
}

input {
  width: 100%;
  border: 1px solid var(--line);
  border-radius: 11px;
  padding: 13px 14px;
  background: #fff;
  color: inherit;
  font: inherit;
}

input:focus {
  outline: 3px solid rgb(149 196 0 / .32);
  border-color: var(--accent-dark);
  outline-offset: 2px;
}

button {
  width: 100%;
  margin-top: 8px;
  border: 1px solid var(--ink);
  border-radius: 11px;
  padding: 13px 16px;
  background: var(--ink);
  color: #fff;
  font: 750 14px/1.2 inherit;
  cursor: pointer;
  transition: transform .15s ease, background .15s ease;
}

button:hover:not(:disabled) { transform: translateY(-1px); background: #2b2e32; }
button:active:not(:disabled) { transform: translateY(0); }
button:focus-visible { outline: 3px solid rgb(149 196 0 / .32); outline-offset: 2px; }
button:disabled { opacity: .55; cursor: wait; }

.message {
  min-height: 18px;
  margin: 5px 0 0;
  color: var(--danger);
  font-size: 12px;
}

.notice {
  margin: 24px 0 0;
  padding-top: 18px;
  border-top: 1px solid var(--line);
  color: #7b8078;
  font-size: 11px;
  line-height: 1.5;
}

@media (max-width: 520px) {
  .login-shell { padding: 14px; }
  .login-card { padding: 30px 24px; border-radius: 20px; }
}