:root {
    --primary: #0f172a;
    --accent: #2563eb;
    --bg-body: #f8fafc;
    --text-main: #1e293b;
    --text-muted: #64748b;
    --border: #e2e8f0;
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Inter', sans-serif;
    background-color: var(--bg-body);
    height: 100vh;
    display: flex;
    justify-content: center;
    align-items: center;
    -webkit-font-smoothing: antialiased;
}

.login-container {
    background: #ffffff;
    padding: 48px 40px;
    border-radius: 12px;
    width: 90%;
    max-width: 400px;
    box-shadow: 0 1px 3px rgba(0,0,0,0.1), 0 10px 15px -3px rgba(0,0,0,0.05);
    border: 1px solid var(--border);
    position: relative;
}

.login-container::before {
    content: "BIENVENIDO";
    display: block;
    text-align: center;
    font-size: 12px;
    font-weight: 700;
    color: var(--accent);
    letter-spacing: 0.15em;
    margin-bottom: 12px;
}

h2 {
    color: var(--primary);
    font-size: 26px;
    font-weight: 800;
    text-align: center;
    margin-bottom: 24px;
    letter-spacing: -0.025em;
}

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

input {
    width: 100%;
    padding: 14px 16px;
    border: 1px solid var(--border);
    border-radius: 8px;
    font-size: 15px;
    color: var(--text-main);
    background-color: #ffffff;
    transition: all 0.2s ease;
}

input:focus {
    outline: none;
    border-color: var(--accent);
    box-shadow: 0 0 0 4px rgba(37, 99, 235, 0.1);
}

button {
    width: 100%;
    padding: 14px;
    background-color: var(--primary);
    color: white;
    border: none;
    border-radius: 8px;
    font-size: 15px;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.2s;
    margin-top: 8px;
}

button:hover {
    background-color: #1e293b;
    transform: translateY(-1px);
}

button:active {
    transform: translateY(0);
}

#mensaje-error {
    background-color: #fef2f2;
    color: #b91c1c;
    padding: 12px 16px;
    border-radius: 8px;
    font-size: 13px;
    margin-bottom: 20px;
    border: 1px solid #fee2e2;
    border-left: 4px solid #ef4444;
}