:root { --bg1: #eef2f7; --bg2: #f7f8fa; --card: #fff; --text: #1d2433; --muted: #6b7385; --border: #dfe3ea; --primary: #1f5fbf; --bad: #b42318; --badbg: #fdecea; --infobg: #eef4fd; }
* { box-sizing: border-box; }
html, body { margin: 0; }
body { font-family: system-ui, "Segoe UI", Arial, sans-serif; color: var(--text); background: linear-gradient(160deg, var(--bg1), var(--bg2)); }
.wrap { min-height: 100vh; display: grid; place-items: center; padding: 16px; }
.box { width: min(380px, 100%); display: flex; flex-direction: column; gap: 14px; padding: 28px; background: var(--card); border: 1px solid var(--border); border-radius: 12px; box-shadow: 0 2px 10px rgba(20, 30, 60, .06); }
section { display: flex; flex-direction: column; gap: 14px; }
section[hidden] { display: none; }
.logo { width: 44px; height: 44px; border-radius: 10px; background: var(--primary); color: #fff; display: grid; place-items: center; font-size: 22px; }
h1 { margin: 0; font-size: 24px; }
.muted { margin: 0; color: var(--muted); }
.hint { margin: 0; color: var(--muted); font-size: 13px; }
.field { display: flex; flex-direction: column; gap: 6px; font-size: 14px; color: var(--muted); }
input { font: inherit; font-size: 16px; padding: 9px 11px; border: 1px solid var(--border); border-radius: 8px; color: var(--text); }
input:focus { outline: 2px solid var(--primary); outline-offset: -1px; border-color: var(--primary); }
.code { font-size: 22px; letter-spacing: 8px; text-align: center; }
button { font: inherit; width: 100%; padding: 10px; border-radius: 8px; border: 1px solid var(--border); background: #fff; cursor: pointer; }
button.primary { background: var(--primary); border-color: var(--primary); color: #fff; }
button.ghost { background: transparent; border-color: transparent; color: var(--primary); }
button:disabled { opacity: .55; cursor: default; }
.notice { padding: 10px 12px; border-radius: 8px; background: var(--infobg); font-size: 14px; }
.notice.bad { background: var(--badbg); color: var(--bad); }
.notice[hidden] { display: none; }
.modes { display: flex; gap: 4px; background: #f0f2f5; padding: 4px; border-radius: 10px; }
.modes[hidden] { display: none; }
.mode { border: 0; background: transparent; color: var(--muted); padding: 7px; }
.mode.active { background: #fff; color: var(--text); box-shadow: 0 1px 2px rgba(0,0,0,.08); }