:root {
    --bg-1: #0f2c43;
    --bg-2: #0b1c2c;
    --card: #0c2740;
    --accent: #4ac1ff;
    --text: #e6edf6;
    --muted: #9fb4c8;
    --error: #ffd7d7;
    --error-text: #a63b3b;
}

* { box-sizing: border-box; }

body {
    font-family: 'Poppins', 'Segoe UI', sans-serif;
    background: radial-gradient(circle at 20% 20%, rgba(74,193,255,0.18), transparent 35%),
                radial-gradient(circle at 80% 0%, rgba(74,193,255,0.14), transparent 30%),
                linear-gradient(135deg, var(--bg-1), var(--bg-2));
    margin: 0;
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 30px;
    color: var(--text);
}

.login-shell {
    width: 100%;
    max-width: 960px;
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(340px, 1fr));
    gap: 24px;
    align-items: stretch;
}

.intro {
    background: rgba(12, 39, 64, 0.55);
    border: 1px solid rgba(255, 255, 255, 0.06);
    border-radius: 14px;
    padding: 32px;
    backdrop-filter: blur(6px);
    box-shadow: 0 18px 60px rgba(0, 0, 0, 0.35);
    position: relative;
    overflow: hidden;
}

.intro::after {
    content: "";
    position: absolute;
    width: 220px;
    height: 220px;
    background: radial-gradient(circle, rgba(74,193,255,0.28), transparent 65%);
    top: -40px;
    right: -60px;
    z-index: 0;
}

.intro-content {
    position: relative;
    z-index: 1;
}

.logo-row {
    display: flex;
    align-items: center;
    gap: 12px;
    margin-bottom: 18px;
}

.logo {
    height: 52px;
    width: auto;
}

.brand-title {
    font-size: 18px;
    font-weight: 600;
    letter-spacing: 0.6px;
}

.intro h2 {
    margin: 6px 0 10px;
    font-size: 24px;
    font-weight: 600;
    color: var(--text);
}

.intro p {
    margin: 0;
    color: var(--muted);
    line-height: 1.5;
    font-size: 14px;
}

.login-card {
    background: var(--card);
    border-radius: 14px;
    padding: 30px;
    border: 1px solid rgba(255, 255, 255, 0.06);
    box-shadow: 0 18px 60px rgba(0, 0, 0, 0.45);
}

h1 {
    margin: 0 0 20px;
    font-size: 22px;
    font-weight: 600;
    color: var(--text);
    text-align: left;
}

.form-group { margin-bottom: 16px; }

label {
    display: block;
    margin-bottom: 6px;
    font-weight: 600;
    font-size: 13px;
    color: var(--muted);
    letter-spacing: 0.2px;
}

input[type="text"], input[type="password"] {
    width: 100%;
    padding: 12px 14px;
    border: 1px solid rgba(255, 255, 255, 0.08);
    border-radius: 10px;
    background: rgba(8, 21, 33, 0.9);
    color: var(--text);
    font-size: 15px;
    transition: border-color 0.2s, box-shadow 0.2s, transform 0.1s;
}

input[type="text"]:focus, input[type="password"]:focus {
    outline: none;
    border-color: var(--accent);
    box-shadow: 0 0 0 4px rgba(74, 193, 255, 0.15);
    transform: translateY(-1px);
}

button {
    width: 100%;
    padding: 12px;
    background: linear-gradient(120deg, #38a6e8, #4ac1ff);
    color: #0b1f30;
    border: none;
    border-radius: 10px;
    font-size: 16px;
    font-weight: 700;
    cursor: pointer;
    letter-spacing: 0.4px;
    transition: transform 0.15s ease, box-shadow 0.15s ease;
}

button:hover { box-shadow: 0 12px 30px rgba(74, 193, 255, 0.25); }
button:active { transform: translateY(1px); }

.alert {
    background-color: var(--error);
    color: var(--error-text);
    padding: 12px 14px;
    border-radius: 10px;
    margin-bottom: 16px;
    border: 1px solid rgba(166, 59, 59, 0.25);
    font-size: 14px;
}

.hint {
    font-size: 13px;
    color: var(--muted);
    margin-top: 16px;
    text-align: center;
}

.hint strong { color: var(--text); }

@media (max-width: 720px) {
    body { padding: 18px; }
    .login-card, .intro { padding: 24px; }
    .login-shell { gap: 16px; }
}