:root {
    color-scheme: light dark;
    --bg:
        radial-gradient(900px 600px at 10% -15%, rgba(255, 255, 255, 0.8), transparent 70%),
        radial-gradient(900px 600px at 95% 5%, rgba(167, 243, 208, 0.24), transparent 75%),
        linear-gradient(145deg, #f5f2ea 0%, #e8e2d5 55%, #ddd5c7 100%);
    --card-bg: rgba(255, 255, 255, 0.25);
    --card-border: rgba(255, 255, 255, 0.7);
    --text-main: #1f2937;
    --text-sub: #4b5563;
    --field-bg: rgba(255, 255, 255, 0.75);
    --field-border: rgba(148, 163, 184, 0.42);
    --btn-bg: linear-gradient(135deg, #2563eb, #38bdf8);
    --btn-text: #f8fafc;
    --danger: #dc2626;
}

@media (prefers-color-scheme: dark) {
    :root {
        --bg:
            radial-gradient(1000px 650px at 10% -15%, rgba(56, 189, 248, 0.2), transparent 68%),
            radial-gradient(1000px 650px at 95% 5%, rgba(99, 102, 241, 0.16), transparent 74%),
            linear-gradient(180deg, #0f172a 0%, #0b1222 52%, #08101c 100%);
        --card-bg: rgba(17, 24, 39, 0.5);
        --card-border: rgba(255, 255, 255, 0.18);
        --text-main: #e5e7eb;
        --text-sub: #9ca3af;
        --field-bg: rgba(15, 23, 42, 0.72);
        --field-border: rgba(148, 163, 184, 0.28);
        --btn-bg: linear-gradient(135deg, #2563eb, #0ea5e9);
        --btn-text: #f8fafc;
        --danger: #fca5a5;
    }
}

* {
    box-sizing: border-box;
}

html,
body {
    width: 100%;
    height: 100%;
    margin: 0;
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
    background: var(--bg);
    color: var(--text-main);
}

.login-shell {
    width: 100%;
    min-height: 100%;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 24px;
}

.login-card {
    width: 100%;
    max-width: 420px;
    border-radius: 24px;
    padding: 32px 26px;
    background: var(--card-bg);
    border: 1px solid var(--card-border);
    backdrop-filter: blur(28px) saturate(170%);
    -webkit-backdrop-filter: blur(28px) saturate(170%);
    box-shadow: 0 30px 60px -34px rgba(15, 23, 42, 0.55);
}

.brand {
    margin: 0 0 8px 0;
    font-size: 0.78rem;
    letter-spacing: 0.32em;
    color: var(--text-sub);
}

.title {
    margin: 0 0 6px 0;
    font-size: 1.9rem;
    font-weight: 700;
    letter-spacing: -0.02em;
}

.subtitle {
    margin: 0 0 20px 0;
    font-size: 0.96rem;
    color: var(--text-sub);
}

.field {
    display: block;
    margin-bottom: 10px;
    font-size: 0.84rem;
    color: var(--text-sub);
}

.input {
    width: 100%;
    border-radius: 14px;
    border: 1px solid var(--field-border);
    background: var(--field-bg);
    color: var(--text-main);
    height: 46px;
    padding: 0 14px;
    font-size: 1rem;
    margin-top: 6px;
    outline: none;
}

.input:focus {
    border-color: rgba(59, 130, 246, 0.65);
    box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.16);
}

.error {
    margin: 6px 0 12px;
    color: var(--danger);
    font-size: 0.88rem;
}

.submit {
    width: 100%;
    margin-top: 10px;
    height: 48px;
    border: 0;
    border-radius: 14px;
    background: var(--btn-bg);
    color: var(--btn-text);
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
}

.lock-popup-backdrop {
    position: fixed;
    inset: 0;
    background: rgba(2, 6, 23, 0.5);
    backdrop-filter: blur(4px);
    -webkit-backdrop-filter: blur(4px);
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 20px;
    z-index: 40;
}

.lock-popup {
    width: 100%;
    max-width: 420px;
    border-radius: 20px;
    padding: 20px 18px 18px;
    background: var(--card-bg);
    border: 1px solid var(--card-border);
    box-shadow: 0 20px 46px -22px rgba(15, 23, 42, 0.62);
}

.lock-popup h2 {
    margin: 0;
    font-size: 1.1rem;
    font-weight: 700;
}

.lock-popup p {
    margin: 10px 0 16px;
    font-size: 0.92rem;
    color: var(--text-sub);
}

.lock-popup-btn {
    width: 100%;
    height: 42px;
    border: 0;
    border-radius: 12px;
    background: var(--btn-bg);
    color: var(--btn-text);
    font-size: 0.92rem;
    font-weight: 600;
    cursor: pointer;
}