* { box-sizing: border-box; }
        body { margin: 0; min-height: 100vh; font-family: "Microsoft YaHei", Arial, sans-serif; color: #172033; background: linear-gradient(135deg, #eef6ff 0%, #f7faf6 48%, #fff4ea 100%); display: flex; flex-direction: column; align-items: center; justify-content: center; gap: 18px; padding: 24px; }
        .panel { width: min(420px, 100%); background: rgba(255,255,255,.94); border: 1px solid #dfe7f2; border-radius: 8px; box-shadow: 0 20px 50px rgba(35, 55, 90, .14); padding: 28px; }
        h1 { margin: 0 0 22px; font-size: 26px; text-align: center; }
        .tabs { display: grid; grid-template-columns: 1fr 1fr; gap: 8px; margin-bottom: 18px; }
        .tabs a { display: block; text-align: center; text-decoration: none; color: #31506f; border: 1px solid #d7e1ea; border-radius: 6px; padding: 10px; background: #f8fbff; font-weight: 600; }
        .tabs a.active { background: #1C86EE; color: white; border-color: #1C86EE; }
        label { display: block; margin: 14px 0 7px; font-weight: 600; font-size: 14px; }
        input { width: 100%; height: 42px; border: 1px solid #cbd5e1; border-radius: 6px; padding: 0 12px; font-size: 15px; background: #fff; }
        input:focus { outline: 2px solid #b8dcff; border-color: #1C86EE; }
        .captcha { display: grid; grid-template-columns: 1fr 128px; gap: 10px; align-items: end; }
        .captcha img { width: 128px; height: 42px; border: 1px solid #cbd5e1; border-radius: 6px; background: white; cursor: pointer; }
        button { width: 100%; height: 44px; margin-top: 20px; border: 0; border-radius: 6px; background: green; color: white; font-size: 16px; font-weight: 700; cursor: pointer; }
        button:hover { background: #0f578f; }
        .alert { margin: 0 0 14px; padding: 10px 12px; border-radius: 6px; font-size: 14px; line-height: 1.5; }
        .error { background: #fff1f0; color: #b42318; border: 1px solid #ffd5d2; }
        .success { background: #effbf3; color: #047857; border: 1px solid #bbf7d0; }
        .site-footer { color: #667085; font-size: 13px; text-align: center; }