:root {
    --primary: #1f3a5f;
    --primary-dark: #162b47;
    --accent: #2b6cb0;
    --text-main: #172133;
    --text-muted: #64748b;
    --danger: #b42318;
    --surface: #ffffff;
    --surface-alt: #f8fafc;
    --border: #dce3ed;
    --shadow: 0 20px 45px rgba(15, 23, 42, 0.15);
}

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

html,
body,
form {
    margin: 0;
    min-height: 100%;
    font-family: "Segoe UI", Tahoma, Arial, sans-serif;
    color: var(--text-main);
    background: linear-gradient(130deg, #0f172a 0%, #1e3a5f 45%, #2d5d8a 100%);
}

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

.login-card {
    width: 100%;
    max-width: 440px;
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: 16px;
    box-shadow: var(--shadow);
    overflow: hidden;
}

.brand-area {
    text-align: center;
    padding: 28px 28px 22px;
    background: linear-gradient(180deg, #f8fbff 0%, #f1f6fc 100%);
    border-bottom: 1px solid var(--border);
}

.brand-logo {
    width: 120px;
    max-width: 100%;
    height: auto;
}

.brand-title {
    margin: 14px 0 8px;
    font-size: 22px;
    font-weight: 700;
    letter-spacing: 0.2px;
    color: var(--primary);
}

.brand-slogan {
    margin: 0;
    font-size: 14px;
    color: var(--text-muted);
}

.form-area {
    padding: 24px 28px 30px;
}

.input-group + .input-group {
    margin-top: 16px;
}

.input-label {
    display: inline-block;
    margin-bottom: 8px;
    font-size: 13px;
    font-weight: 600;
    color: var(--text-main);
}

.input-control {
    width: 100%;
    height: 44px;
    padding: 0 13px;
    border: 1px solid #c7d3e3;
    border-radius: 10px;
    font-size: 14px;
    outline: none;
    transition: border-color 0.2s ease, box-shadow 0.2s ease;
}

.input-control:focus {
    border-color: var(--accent);
    box-shadow: 0 0 0 4px rgba(43, 108, 176, 0.15);
}

.error-message {
    display: block;
    margin-top: 14px;
    font-size: 13px;
    line-height: 1.5;
    color: var(--danger);
}

.btn-login {
    width: 100%;
    margin-top: 18px;
    height: 46px;
    border: none;
    border-radius: 10px;
    background: linear-gradient(90deg, var(--primary) 0%, var(--accent) 100%);
    color: #ffffff;
    font-size: 15px;
    font-weight: 600;
    cursor: pointer;
    transition: transform 0.15s ease, box-shadow 0.2s ease, background 0.2s ease;
}

.btn-login:hover {
    box-shadow: 0 8px 18px rgba(31, 58, 95, 0.32);
    transform: translateY(-1px);
}

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

@media (max-width: 600px) {
    .login-page {
        padding: 14px;
    }

    .brand-area {
        padding: 24px 18px 18px;
    }

    .form-area {
        padding: 20px 18px 24px;
    }

    .brand-title {
        font-size: 20px;
    }
}