/* ============================================================
   Login Page — Responsive (PC two-column + Mobile single)
   ============================================================ */
:root {
    --bg:      #0d1117;
    --surface: #161c2a;
    --border:  rgba(255,255,255,0.08);
    --text:    #e8eef8;
    --muted:   #7a8aaa;
    --accent:  #4ade9e;
    --accent2: #17a96b;
    --input-bg: rgba(255,255,255,0.05);
    --radius:  16px;
}

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

body {
    margin: 0;
    min-height: 100vh;
    font-family: "PingFang SC","Microsoft YaHei","Helvetica Neue",Arial,sans-serif;
    -webkit-font-smoothing: antialiased;
    background: var(--bg);
    background-image:
        radial-gradient(ellipse 55% 40% at 5% 5%,   rgba(78,222,158,0.10) 0%, transparent 55%),
        radial-gradient(ellipse 45% 35% at 95% 95%,  rgba(50,100,255,0.12) 0%, transparent 50%);
    color: var(--text);
}

/* ============================================================
   PC Layout — two-column
   ============================================================ */
.login-page {
    display: grid;
    grid-template-columns: 1fr 1fr;
    min-height: 100vh;
}

/* Left panel — branding */
.login-left {
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: flex-start;
    padding: 60px 56px;
    background: linear-gradient(160deg, rgba(22,30,46,0.95) 0%, rgba(12,17,28,0.98) 100%);
    border-right: 1px solid var(--border);
    position: relative;
    overflow: hidden;
}

.login-left::before {
    content: '';
    position: absolute;
    top: -80px; left: -80px;
    width: 420px; height: 420px;
    border-radius: 50%;
    background: radial-gradient(circle, rgba(78,222,158,0.12), transparent 70%);
    pointer-events: none;
}

.login-left::after {
    content: '';
    position: absolute;
    bottom: -60px; right: -60px;
    width: 300px; height: 300px;
    border-radius: 50%;
    background: radial-gradient(circle, rgba(50,100,255,0.10), transparent 70%);
    pointer-events: none;
}

.login-brand {
    display: flex;
    flex-direction: column;
    gap: 6px;
    margin-bottom: 40px;
    position: relative;
}

.login-brand__eyebrow {
    font-size: 11px;
    font-weight: 600;
    letter-spacing: 0.2em;
    text-transform: uppercase;
    color: var(--accent);
}

.login-brand__name {
    font-size: 40px;
    font-weight: 800;
    line-height: 1;
    letter-spacing: -0.02em;
}

.login-brand__logo {
    max-width: 200px;
    max-height: 60px;
    object-fit: contain;
    margin-bottom: 16px;
}

.login-tagline {
    position: relative;
    font-size: 22px;
    font-weight: 700;
    line-height: 1.4;
    max-width: 380px;
    margin: 0 0 20px;
}

.login-tagline-sub {
    position: relative;
    font-size: 14px;
    color: var(--muted);
    line-height: 1.7;
    max-width: 360px;
    margin: 0;
}

.login-features {
    display: flex;
    flex-direction: column;
    gap: 14px;
    margin-top: 40px;
    position: relative;
}

.login-feature {
    display: flex;
    align-items: center;
    gap: 12px;
    font-size: 14px;
    color: var(--muted);
}

.login-feature-dot {
    width: 8px; height: 8px;
    border-radius: 50%;
    background: var(--accent);
    flex-shrink: 0;
}

/* Right panel — form */
.login-right {
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    padding: 60px 40px;
    position: relative;
}

/* Language switcher */
.login-lang {
    position: absolute;
    top: 24px;
    right: 24px;
}

.login-lang__btn {
    border: 1px solid var(--border);
    background: rgba(255,255,255,0.05);
    color: var(--text);
    border-radius: 999px;
    padding: 7px 14px;
    font-size: 13px;
    font-weight: 600;
    cursor: pointer;
    transition: background .18s;
}

.login-lang__btn:hover { background: rgba(255,255,255,0.10); }

.login-lang__menu {
    display: none;
    position: absolute;
    top: calc(100% + 8px);
    right: 0;
    min-width: 140px;
    background: #111827;
    border: 1px solid rgba(255,255,255,0.12);
    border-radius: var(--radius);
    padding: 6px;
    box-shadow: 0 16px 48px rgba(0,0,0,.5);
    z-index: 200;
}

.login-lang__menu.is-open { display: block; }

.login-lang__menu span {
    display: block;
    padding: 9px 12px;
    border-radius: 8px;
    cursor: pointer;
    font-size: 13px;
    font-weight: 500;
    color: var(--text);
    transition: background .15s;
}

.login-lang__menu span:hover { background: rgba(255,255,255,0.08); }

/* Form card */
.login-card {
    width: 100%;
    max-width: 400px;
}

.login-card__title {
    font-size: 30px;
    font-weight: 800;
    margin: 0 0 6px;
    letter-spacing: -0.02em;
}

.login-card__sub {
    font-size: 14px;
    color: var(--muted);
    margin: 0 0 36px;
}

.login-field {
    margin-bottom: 16px;
}

.login-field label {
    display: block;
    font-size: 12px;
    font-weight: 600;
    letter-spacing: 0.06em;
    text-transform: uppercase;
    color: var(--muted);
    margin-bottom: 8px;
}

.login-field input {
    display: block;
    width: 100%;
    height: 52px;
    padding: 0 18px;
    border-radius: var(--radius);
    border: 1px solid var(--border);
    background: var(--input-bg);
    color: var(--text);
    font-size: 15px;
    outline: none;
    transition: border-color .2s, background .2s;
    font-family: inherit;
}

.login-field input:focus {
    border-color: var(--accent);
    background: rgba(78,222,158,0.04);
}

.login-field input::placeholder { color: var(--muted); }

.login-submit {
    display: block;
    width: 100%;
    height: 52px;
    margin: 24px 0 14px;
    border-radius: var(--radius);
    border: none;
    background: linear-gradient(135deg, var(--accent), var(--accent2));
    color: #07180e;
    font-size: 16px;
    font-weight: 700;
    cursor: pointer;
    transition: opacity .2s, transform .2s;
    font-family: inherit;
}

.login-submit:hover  { opacity: .88; transform: translateY(-1px); }
.login-submit:active { opacity: .75; transform: translateY(0); }

.login-register {
    display: block;
    width: 100%;
    height: 52px;
    border-radius: var(--radius);
    border: 1px solid rgba(78,222,158,0.35);
    background: transparent;
    color: var(--accent);
    font-size: 15px;
    font-weight: 600;
    text-align: center;
    line-height: 52px;
    transition: background .2s, border-color .2s;
    margin-bottom: 20px;
}

.login-register:hover {
    background: rgba(78,222,158,0.06);
    border-color: var(--accent);
}

.login-footer {
    display: flex;
    justify-content: center;
}

.login-footer a {
    color: var(--muted);
    font-size: 13px;
    transition: color .15s;
}

.login-footer a:hover { color: var(--text); }

/* ============================================================
   Mobile — single column
   ============================================================ */
@media (max-width: 768px) {
    .login-page {
        display: block;
        min-height: 100vh;
    }

    .login-left { display: none; }

    .login-right {
        min-height: 100vh;
        padding: 80px 24px 40px;
        justify-content: flex-start;
    }

    .login-lang { top: 20px; right: 20px; }

    /* Mobile logo at top */
    .login-mobile-brand {
        display: flex;
        flex-direction: column;
        align-items: center;
        margin-bottom: 32px;
        width: 100%;
    }

    .login-mobile-brand img {
        max-width: 140px;
        max-height: 50px;
        object-fit: contain;
        margin-bottom: 10px;
    }

    .login-mobile-brand__name {
        font-size: 22px;
        font-weight: 800;
        letter-spacing: -0.01em;
    }

    .login-card { max-width: 100%; }
    .login-card__title { font-size: 24px; }

    .login-field input { height: 48px; font-size: 16px; }
    .login-submit { height: 48px; font-size: 15px; margin-top: 20px; }
    .login-register { height: 48px; line-height: 48px; }
}

/* Desktop — hide mobile brand */
@media (min-width: 769px) {
    .login-mobile-brand { display: none; }
}