:root {
    --primary: #1d4ed8;
    --primary-hover: #1e40af;
    --background: #f3f4f6;
    --foreground: #111827;
    --card: #ffffff;
    --card-foreground: #111827;
    --border: #e5e7eb;
    --input: #e5e7eb;
    --ring: #93c5fd;
    --radius: 0.5rem;
}

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

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
    background: linear-gradient(to bottom right, #1f2937, #111827);
    color: var(--foreground);
    display: flex;
    align-items: center;
    justify-content: center;
    min-height: 100vh;
}

.container {
    width: 100%;
    max-width: 400px;
    padding: 2rem;
    background-color: var(--card);
    border-radius: var(--radius);
    box-shadow: 0 25px 50px -12px rgba(0, 0, 0, 0.25);
}

h1 {
    font-size: 1.875rem;
    font-weight: bold;
    text-align: center;
    margin-bottom: 1.5rem;
    color: var(--card-foreground);
}

.form-group {
    margin-bottom: 1rem;
}

label {
    display: block;
    font-size: 0.875rem;
    font-weight: 500;
    margin-bottom: 0.5rem;
}

input {
    width: 100%;
    padding: 0.5rem 0.75rem;
    font-size: 0.875rem;
    line-height: 1.25rem;
    border: 1px solid var(--input);
    border-radius: var(--radius);
    background-color: var(--background);
    transition: border-color 0.15s ease-in-out, box-shadow 0.15s ease-in-out;
}

input:focus {
    outline: none;
    border-color: var(--ring);
    box-shadow: 0 0 0 3px rgba(147, 197, 253, 0.5);
}

.submit-button {
    width: 100%;
    padding: 0.5rem 1rem;
    font-size: 0.875rem;
    font-weight: 500;
    color: #ffffff;
    background-color: var(--primary);
    border: none;
    border-radius: var(--radius);
    cursor: pointer;
    transition: background-color 0.15s ease-in-out;
}

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

.submit-button:disabled {
    opacity: 0.5;
    cursor: not-allowed;
}

.forgot-password {
    display: block;
    text-align: center;
    font-size: 0.875rem;
    color: var(--primary);
    text-decoration: none;
    margin-top: 1rem;
}

.forgot-password:hover {
    text-decoration: underline;
}

.spinner {
    display: inline-block;
    width: 1rem;
    height: 1rem;
    border: 2px solid rgba(255, 255, 255, 0.3);
    border-radius: 50%;
    border-top-color: #ffffff;
    animation: spin 1s ease-in-out infinite;
    margin-right: 0.5rem;
}

@keyframes spin {
    to { transform: rotate(360deg); }
}

@media (max-width: 640px) {
    .container {
        max-width: 90%;
    }
}