:root {
    --bg-soft: #f2f6f8;
    --bg-gradient: radial-gradient(circle at top right, #d7eef0 0%, #f7fbfc 45%, #eef3f8 100%);
    --primary: #0f766e;
    --primary-hover: #0a5e58;
    --text-main: #15222d;
    --text-muted: #516171;
    --card-bg: #ffffff;
    --border: #d4dfe7;
    --danger-bg: #fdecec;
    --danger-text: #9f1d1d;
}

* {
    box-sizing: border-box;
}

body {
    margin: 0;
    min-height: 100vh;
    font-family: "Segoe UI", "Helvetica Neue", sans-serif;
    color: var(--text-main);
    background: var(--bg-gradient), var(--bg-soft);
}

.login-page {
    min-height: 100vh;
    display: grid;
    place-items: center;
    padding: 20px;
}

.login-card {
    width: 100%;
    max-width: 420px;
    background: var(--card-bg);
    border: 1px solid var(--border);
    border-radius: 16px;
    padding: 28px;
    box-shadow: 0 16px 40px rgba(16, 39, 58, 0.12);
}

.login-card h1 {
    margin: 0;
    font-size: 1.65rem;
    color: var(--primary);
}

.subtitle {
    margin: 8px 0 20px;
    color: var(--text-muted);
    font-size: 0.95rem;
}

label {
    display: block;
    margin-bottom: 6px;
    font-weight: 600;
    font-size: 0.9rem;
}

input {
    width: 100%;
    padding: 12px 14px;
    border: 1px solid var(--border);
    border-radius: 10px;
    margin-bottom: 14px;
    font-size: 0.95rem;
    outline: none;
    transition: border-color 0.2s;
}

input:focus {
    border-color: var(--primary);
}

button {
    width: 100%;
    border: 0;
    border-radius: 10px;
    padding: 12px;
    font-size: 1rem;
    font-weight: 700;
    cursor: pointer;
    color: #fff;
    background: var(--primary);
    transition: background 0.2s;
}

button:hover {
    background: var(--primary-hover);
}

.alert {
    margin-bottom: 14px;
    border-radius: 10px;
    padding: 10px 12px;
    background: var(--danger-bg);
    color: var(--danger-text);
    border: 1px solid #f8c7c7;
    font-size: 0.92rem;
}

.alert-success {
    background: #e9f9ef;
    color: #13613f;
    border-color: #c6efda;
}

@media (max-width: 520px) {
    .login-card {
        padding: 22px;
        border-radius: 14px;
    }
}