:root {
    --purple: #8b5cf6;
    --purple-hover: #7c3aed;
    --black: #030213;
    --white: #ffffff;
}

* {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC",
                 "Hiragino Sans GB", "Microsoft YaHei", "Helvetica Neue",
                 sans-serif;
    font-weight: var(--font-weight-normal, 400);
    -webkit-font-smoothing: antialiased;
}

body {
    background-color: #000000;
    margin: 0;
    padding: 0;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: flex-start;
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC",
                 "Hiragino Sans GB", "Microsoft YaHei", "Helvetica Neue",
                 sans-serif;
}

.brand-mark {
    text-align: center;
    margin-top: 60px;
    margin-bottom: 40px;
    width: 100%;
}

.brand-mark .logo {
    max-width: 900px;
    width: 100%;
    height: auto;
    display: block;
    margin: 0 auto;
}

.login-card {
    background: var(--white);
    border-radius: 16px;
    padding: 40px 32px 36px;
    width: 100%;
    max-width: 300px;
    box-sizing: border-box;
}

.login-card h2 {
    font-size: 24px;
    font-weight: 600;
    color: var(--black);
    margin: 0 0 6px 0;
    text-align: center;
}

.login-card .subtitle {
    font-size: 14px;
    color: rgba(0,0,0,0.45);
    margin: 0 0 36px 0;
    text-align: center;
}

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

.form-group label {
    width: calc(50% - 6px);
    flex: none;
    font-size: 14px;
    font-weight: 500;
    color: var(--black);
    text-align: center;
    box-sizing: border-box;
}

.form-group input {
    width: calc(50% - 6px);
    flex: none;
    padding: 11px 16px;
    text-align: center;
    border: 1.5px solid rgba(0,0,0,0.08);
    border-radius: 10px;
    font-size: 15px;
    color: var(--black);
    background: #f5f5f7;
    box-sizing: border-box;
    transition: all 0.15s ease;
    outline: none;
}

.form-group input:focus {
    border-color: var(--purple);
    background: var(--white);
    box-shadow: 0 0 0 3px rgba(139, 92, 246, 0.12);
}

.form-group input::placeholder {
    color: rgba(0,0,0,0.25);
}

.form-group input:hover {
    background: #f0f0f2;
}

.btn-login {
    width: 100%;
    background-color: var(--purple);
    color: var(--white);
    border: none;
    border-radius: 10px;
    padding: 13px 24px;
    font-size: 15px;
    font-weight: 500;
    cursor: pointer;
    transition: all 0.15s ease;
    margin-top: 8px;
}

.btn-login:hover {
    background-color: var(--purple-hover);
    box-shadow: 0 4px 16px rgba(139, 92, 246, 0.35);
    transform: translateY(-1px);
}

.btn-login:active {
    transform: translateY(0);
}

.alert {
    background-color: rgba(212, 24, 61, 0.08);
    color: #d4183d;
    padding: 12px 16px;
    border-radius: 10px;
    font-size: 14px;
    margin-bottom: 20px;
    border: 1px solid rgba(212, 24, 61, 0.15);
}