:root {
    --primary-color: #4285f4;
    --error-color: #d93025;
    --success-color: #1e8e3e;
    --bg-gradient: linear-gradient(135deg, #f5f7fa 0%, #c3cfe2 100%);
    --card-bg: #ffffff;
    --text-color: #3c4043;
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background: var(--bg-gradient);
    min-height: 100vh;
    margin: 0;
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--text-color);
}

.container {
    width: 100%;
    max-width: 500px;
    padding: 20px;
}

.card {
    background: var(--card-bg);
    border-radius: 8px;
    box-shadow: 0 4px 6px rgba(0,0,0,0.1);
    padding: 40px;
    text-align: center;
}

h1 {
    margin-top: 0;
    font-size: 24px;
}

.subtitle {
    color: #70757a;
    margin-bottom: 30px;
}

.info-box {
    background: #f8f9fa;
    border: 1px solid #dadce0;
    border-radius: 4px;
    padding: 15px;
    margin-bottom: 25px;
    text-align: left;
}

.warning {
    color: var(--error-color);
    font-size: 0.9em;
    margin-top: 10px;
}

.hidden {
    display: none !important;
}

.google-btn {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 100%;
    background: white;
    color: #3c4043;
    border: 1px solid #dadce0;
    border-radius: 4px;
    padding: 10px;
    font-size: 16px;
    font-weight: 500;
    cursor: pointer;
    transition: background-color .2s ease;
}

.google-btn:hover {
    background-color: #f8f9fa;
}

.google-btn img {
    width: 18px;
    height: 18px;
    margin-right: 12px;
}

.instructions {
    margin-top: 30px;
    text-align: left;
    font-size: 0.9em;
}

.instructions h3 {
    font-size: 1.1em;
    margin-bottom: 10px;
}

.instructions ol {
    padding-left: 20px;
    color: #5f6368;
}

.instructions code {
    background: #f1f3f4;
    padding: 2px 4px;
    border-radius: 3px;
}

/* Callback page styles */
.spinner {
    border: 4px solid rgba(0,0,0,0.1);
    width: 36px;
    height: 36px;
    border-radius: 50%;
    border-left-color: var(--primary-color);
    animation: spin 1s linear infinite;
    margin: 0 auto 20px;
}

@keyframes spin {
    0% { transform: rotate(0deg); }
    100% { transform: rotate(360deg); }
}

.success-text { color: var(--success-color); }
.error-text { color: var(--error-color); }

.token-section {
    text-align: left;
    margin: 25px 0;
}

.token-box {
    background: #202124;
    color: #e8eaed;
    font-family: 'Courier New', Courier, monospace;
    padding: 15px;
    border-radius: 4px;
    word-break: break-all;
    font-size: 0.85em;
    max-height: 150px;
    overflow-y: auto;
    margin-bottom: 15px;
}

.form-group {
    text-align: left;
    margin-bottom: 20px;
}

.form-group label {
    display: block;
    margin-bottom: 5px;
    font-weight: 500;
}

.form-group input {
    width: 100%;
    padding: 10px;
    border: 1px solid #dadce0;
    border-radius: 4px;
    box-sizing: border-box;
}

.form-group input:disabled {
    background: #f1f3f4;
}

.btn {
    padding: 10px 24px;
    border-radius: 4px;
    border: 1px solid #dadce0;
    background: white;
    cursor: pointer;
    font-weight: 500;
}

.btn.primary {
    background: var(--primary-color);
    color: white;
    border-color: var(--primary-color);
}