:root {
    color-scheme: light;
    --login-bg: #f4f7fb;
    --login-surface-top: rgba(255, 255, 255, 0.96);
    --login-ambient-cyan: rgba(52, 211, 213, 0.1);
    --login-ambient-blue: rgba(59, 130, 246, 0.09);
    --login-panel: rgba(255, 255, 255, 0.84);
    --login-border: rgba(11, 44, 67, 0.12);
    --login-text: #0b2435;
    --login-muted: #5d7482;
    --login-accent: #0066ff;
    --login-accent-2: #00b7c7;
    --line-green: #06c755;
    --line-green-hover: #05b34c;
    --login-shadow: 0 24px 70px rgba(11, 42, 65, 0.16);
    --login-focus: 0 0 0 4px rgba(0, 102, 255, 0.2);
    --login-error: #b64d57;
    --login-error-surface: rgba(255, 107, 107, 0.12);
}

[data-bs-theme="dark"] {
    color-scheme: dark;
    --login-bg: #07121d;
    --login-surface-top: rgba(17, 36, 52, 0.72);
    --login-ambient-cyan: rgba(32, 211, 203, 0.075);
    --login-ambient-blue: rgba(61, 165, 255, 0.075);
    --login-panel: rgba(14, 31, 45, 0.86);
    --login-border: rgba(168, 225, 236, 0.18);
    --login-text: #eaf7fb;
    --login-muted: #9cb4c0;
    --login-accent: #43a5ff;
    --login-accent-2: #22d2cb;
    --login-shadow: 0 28px 80px rgba(0, 0, 0, 0.36);
    --login-focus: 0 0 0 4px rgba(67, 165, 255, 0.25);
    --login-error: #ffb3b3;
    --login-error-surface: rgba(255, 107, 107, 0.16);
}

@media (prefers-color-scheme: dark) {
    :root:not([data-bs-theme="light"]) {
        color-scheme: dark;
        --login-bg: #07121d;
        --login-surface-top: rgba(17, 36, 52, 0.72);
        --login-ambient-cyan: rgba(32, 211, 203, 0.075);
        --login-ambient-blue: rgba(61, 165, 255, 0.075);
        --login-panel: rgba(14, 31, 45, 0.86);
        --login-border: rgba(168, 225, 236, 0.18);
        --login-text: #eaf7fb;
        --login-muted: #9cb4c0;
        --login-accent: #43a5ff;
        --login-accent-2: #22d2cb;
        --login-shadow: 0 28px 80px rgba(0, 0, 0, 0.36);
        --login-focus: 0 0 0 4px rgba(67, 165, 255, 0.25);
        --login-error: #ffb3b3;
        --login-error-surface: rgba(255, 107, 107, 0.16);
    }
}

*,
*::before,
*::after {
    box-sizing: border-box;
}

html,
body {
    min-height: 100%;
}

body {
    min-height: 100svh;
    margin: 0;
    padding: clamp(1rem, 4vw, 3rem);
    padding-top: max(clamp(1rem, 4vw, 3rem), env(safe-area-inset-top, 0px));
    padding-bottom: max(clamp(1rem, 4vw, 3rem), env(safe-area-inset-bottom, 0px));
    display: grid;
    place-items: center;
    background: var(--login-bg);
    color: var(--login-text);
    font-family: "Noto Sans TC", "PingFang TC", "Microsoft JhengHei", system-ui, sans-serif;
    overflow-x: hidden;
    position: relative;
    isolation: isolate;
}

body::before {
    content: "";
    position: absolute;
    inset: 0 0 auto;
    z-index: -1;
    height: clamp(520px, 68vw, 920px);
    pointer-events: none;
    background:
        radial-gradient(
            clamp(520px, 44vw, 900px) clamp(360px, 34vw, 640px) at 8% 4%,
            var(--login-ambient-cyan),
            transparent 72%
        ),
        radial-gradient(
            clamp(560px, 48vw, 1000px) clamp(380px, 36vw, 700px) at 94% 7%,
            var(--login-ambient-blue),
            transparent 74%
        ),
        linear-gradient(180deg, var(--login-surface-top) 0, var(--login-bg) 38rem, var(--login-bg) 100%);
    background-repeat: no-repeat;
}

.login-page {
    position: relative;
    z-index: 1;
    width: min(100%, 480px);
}

.login-card {
    position: relative;
    width: 100%;
    padding: clamp(2rem, 6vw, 3.25rem);
    background: var(--login-panel);
    border: 1px solid var(--login-border);
    border-radius: 2rem;
    box-shadow: var(--login-shadow);
    overflow: hidden;
}

@supports ((backdrop-filter: blur(1px)) or (-webkit-backdrop-filter: blur(1px))) {
    .login-card {
        backdrop-filter: blur(18px) saturate(125%);
        -webkit-backdrop-filter: blur(18px) saturate(125%);
    }
}

.login-card::before {
    content: "";
    position: absolute;
    inset: 0 0 auto;
    height: 4px;
    background: linear-gradient(90deg, var(--line-green), var(--login-accent-2), var(--login-accent));
}

.brand-lockup {
    text-align: center;
}

.brand-kicker {
    display: block;
    margin-bottom: 1.5rem;
    color: var(--login-accent-2);
    font-size: 0.68rem;
    font-weight: 800;
    letter-spacing: 0.2em;
    text-transform: uppercase;
}

.brand-logo {
    display: block;
    width: clamp(4.5rem, 20vw, 5.5rem);
    height: auto;
    aspect-ratio: 1;
    margin: 0 auto 1.25rem;
    object-fit: contain;
    filter: drop-shadow(0 10px 16px rgba(3, 28, 49, 0.2));
}

.brand-title {
    margin: 0;
    color: var(--login-text);
    font-size: clamp(1.65rem, 5vw, 2.1rem);
    font-weight: 900;
    letter-spacing: -0.04em;
}

.brand-title span {
    color: var(--login-accent-2);
}

.login-state {
    margin-top: 2.25rem;
    text-align: center;
}

.login-state-message {
    margin: 0 0 1.25rem;
    color: var(--login-muted);
    font-size: 0.95rem;
}

.button {
    min-height: 3.25rem;
    width: 100%;
    padding: 0.75rem 1.25rem;
    border: 1px solid transparent;
    border-radius: 1rem;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 0.75rem;
    color: #fff;
    font: inherit;
    font-weight: 800;
    text-decoration: none;
    cursor: pointer;
    transition: transform 160ms ease, box-shadow 160ms ease, background-color 160ms ease, border-color 160ms ease;
}

.button:hover {
    transform: translateY(-2px);
}

.button:focus-visible {
    outline: none;
    box-shadow: var(--login-focus);
}

.button-line {
    background: var(--line-green);
    box-shadow: 0 12px 24px rgba(6, 199, 85, 0.22);
}

.button-line:hover {
    background: var(--line-green-hover);
    box-shadow: 0 16px 28px rgba(6, 199, 85, 0.3);
}

.button-ghost {
    color: var(--login-text);
    background: transparent;
    border-color: var(--login-border);
}

.button-ghost:hover {
    background: rgba(255, 255, 255, 0.08);
    border-color: var(--login-accent-2);
}

.line-glyph {
    display: inline-grid;
    place-items: center;
    min-width: 2rem;
    height: 2rem;
    padding: 0 0.25rem;
    border-radius: 0.65rem;
    background: rgba(255, 255, 255, 0.96);
    color: var(--line-green);
    font-size: 0.58rem;
    font-weight: 900;
    letter-spacing: -0.06em;
}

.user-avatar {
    display: block;
    width: 5.5rem;
    height: 5.5rem;
    margin: 0 auto 1.25rem;
    border: 3px solid var(--line-green);
    border-radius: 50%;
    object-fit: cover;
    box-shadow: 0 12px 24px rgba(6, 199, 85, 0.18);
}

.visitor-name {
    margin: 0 0 0.5rem;
    font-size: 1.15rem;
    font-weight: 800;
}

.visitor-note {
    margin: 0 0 1.25rem;
    color: var(--login-error);
    font-size: 0.86rem;
    line-height: 1.7;
}

.visitor-note span {
    color: var(--login-muted);
}

.status-spinner {
    width: 2rem;
    height: 2rem;
    margin: 0 auto 1rem;
    border: 3px solid rgba(0, 183, 199, 0.2);
    border-top-color: var(--login-accent-2);
    border-radius: 50%;
    animation: spin 760ms linear infinite;
}

.status-icon {
    display: grid;
    place-items: center;
    width: 3rem;
    height: 3rem;
    margin: 0 auto 1rem;
    border-radius: 1rem;
    color: var(--login-accent-2);
    background: rgba(0, 183, 199, 0.12);
    font-size: 1.4rem;
    font-weight: 900;
}

.status-icon.error {
    color: var(--login-error);
    background: var(--login-error-surface);
}

.status-error {
    margin: 0 0 1.25rem;
    color: var(--login-error);
    line-height: 1.7;
}

.auth-failure-state {
    max-width: 25rem;
    margin-inline: auto;
}

.auth-failure-state .status-icon {
    width: 3.5rem;
    height: 3.5rem;
    margin-bottom: 1.25rem;
}

.auth-failure-eyebrow {
    margin: 0 0 0.55rem;
    color: var(--login-error);
    font-size: 0.78rem;
    font-weight: 800;
    letter-spacing: 0.12em;
}

.auth-failure-title {
    margin: 0;
    color: var(--login-text);
    font-size: clamp(1.35rem, 4vw, 1.7rem);
    font-weight: 900;
    letter-spacing: -0.03em;
}

.auth-failure-copy {
    margin: 0.85rem 0 1.5rem;
    color: var(--login-muted);
    line-height: 1.75;
}

.auth-failure-actions {
    display: grid;
    gap: 0.75rem;
}

.footer-text {
    margin: 2.25rem 0 0;
    color: var(--login-muted);
    font-size: 0.76rem;
    text-align: center;
}

.footer-text p {
    margin: 0;
}

.fade-in {
    animation: fadeIn 300ms ease-out both;
}

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(8px); }
    to { opacity: 1; transform: translateY(0); }
}

@keyframes spin {
    to { transform: rotate(360deg); }
}

@media (max-width: 480px) {
    body { padding: 0.75rem; }
    .login-card { border-radius: 1.5rem; }
}

@media (prefers-reduced-motion: reduce) {
    *,
    *::before,
    *::after {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        scroll-behavior: auto !important;
        transition-duration: 0.01ms !important;
    }
}