:root {
    --bg: #0d1117;
    --card-bg: #161b22;
    --border: #30363d;
    --text: #e6edf3;
    --text-secondary: #8b949e;
    --accent: #58a6ff;
    --accent-hover: #79c0ff;
    --success: #3fb950;
    --error: #f85149;
    --warning: #d29922;
    --font: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
}

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

body {
    font-family: var(--font);
    background: var(--bg);
    color: var(--text);
    min-height: 100vh;
    line-height: 1.6;
}

.container {
    max-width: 640px;
    margin: 0 auto;
    padding: 40px 20px;
}

/* Header */
header {
    text-align: center;
    margin-bottom: 32px;
}

.logo-row {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 16px;
    margin-bottom: 24px;
}

.logo-link { display: flex; align-items: center; }

.logo {
    height: 40px;
    width: auto;
    filter: brightness(1.1);
}

.logo-separator {
    color: var(--text-secondary);
    font-size: 20px;
    font-weight: 300;
}

h1 {
    font-size: 2.2rem;
    font-weight: 800;
    margin-bottom: 8px;
    letter-spacing: -0.02em;
}

.accent { color: var(--accent); }

.subtitle {
    color: var(--text-secondary);
    font-size: 1rem;
    max-width: 480px;
    margin: 0 auto;
}

/* Cards */
.card {
    background: var(--card-bg);
    border: 1px solid var(--border);
    border-radius: 12px;
    padding: 24px;
    margin-bottom: 20px;
}

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

.form-group label {
    display: block;
    font-size: 0.875rem;
    font-weight: 600;
    margin-bottom: 6px;
    color: var(--text);
}

.form-group input,
.form-group select {
    width: 100%;
    padding: 10px 14px;
    font-size: 0.95rem;
    font-family: var(--font);
    background: var(--bg);
    border: 1px solid var(--border);
    border-radius: 8px;
    color: var(--text);
    transition: border-color 0.2s;
}

.form-group input:focus,
.form-group select:focus {
    outline: none;
    border-color: var(--accent);
    box-shadow: 0 0 0 2px rgba(88, 166, 255, 0.15);
}

.form-group input::placeholder {
    color: var(--text-secondary);
    opacity: 0.6;
}

.hint {
    font-size: 0.8rem;
    color: var(--text-secondary);
    margin-top: 4px;
}

.hint.center { text-align: center; }

.error-text {
    font-size: 0.8rem;
    color: var(--error);
    display: block;
    margin-top: 4px;
    min-height: 18px;
}

.key-status {
    font-size: 0.8rem;
    display: block;
    margin-top: 4px;
    min-height: 18px;
}

.key-status.valid { color: var(--success); }
.key-status.invalid { color: var(--error); }
.key-status.checking { color: var(--warning); }

/* API Key Toggle */
.api-key-section {
    margin-bottom: 16px;
}

.api-key-section summary {
    cursor: pointer;
    color: var(--accent);
    font-size: 0.9rem;
    font-weight: 500;
    padding: 8px 0;
}

.api-key-section summary:hover {
    color: var(--accent-hover);
}

.api-key-content {
    padding-top: 12px;
}

.api-key-toggle {
    display: flex;
    gap: 8px;
    margin-bottom: 16px;
}

.toggle-btn {
    flex: 1;
    padding: 8px 16px;
    font-size: 0.85rem;
    font-family: var(--font);
    font-weight: 500;
    background: var(--bg);
    border: 1px solid var(--border);
    border-radius: 8px;
    color: var(--text-secondary);
    cursor: pointer;
    transition: all 0.2s;
}

.toggle-btn.active {
    border-color: var(--accent);
    color: var(--accent);
    background: rgba(88, 166, 255, 0.08);
}

.toggle-btn:hover:not(.active) {
    border-color: var(--text-secondary);
    color: var(--text);
}

/* Buttons */
.primary-btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 100%;
    padding: 12px 24px;
    font-size: 1rem;
    font-weight: 600;
    font-family: var(--font);
    background: var(--accent);
    color: #fff;
    border: none;
    border-radius: 8px;
    cursor: pointer;
    transition: background 0.2s;
    text-decoration: none;
    gap: 8px;
}

.primary-btn:hover {
    background: var(--accent-hover);
}

.primary-btn:disabled {
    opacity: 0.5;
    cursor: not-allowed;
}

.primary-btn.small {
    width: auto;
    padding: 10px 20px;
    font-size: 0.9rem;
}

.secondary-btn {
    display: inline-block;
    padding: 10px 20px;
    font-size: 0.9rem;
    font-weight: 600;
    font-family: var(--font);
    background: transparent;
    color: var(--accent);
    border: 1px solid var(--accent);
    border-radius: 8px;
    cursor: pointer;
    transition: all 0.2s;
    text-decoration: none;
}

.secondary-btn:hover {
    background: rgba(88, 166, 255, 0.1);
}

.link-btn {
    background: none;
    border: none;
    color: var(--accent);
    font-size: 0.85rem;
    font-family: var(--font);
    cursor: pointer;
    margin-top: 8px;
}

.link-btn:disabled {
    color: var(--text-secondary);
    cursor: not-allowed;
}

/* OTP */
.otp-input-row {
    display: flex;
    gap: 12px;
    align-items: center;
    margin: 16px 0 8px;
}

.otp-input {
    flex: 1;
    padding: 12px 16px;
    font-size: 1.4rem;
    font-family: var(--font);
    font-weight: 600;
    letter-spacing: 0.3em;
    text-align: center;
    background: var(--bg);
    border: 1px solid var(--border);
    border-radius: 8px;
    color: var(--text);
}

.otp-input:focus {
    outline: none;
    border-color: var(--accent);
}

/* Spinner */
.spinner {
    width: 18px;
    height: 18px;
    border: 2px solid rgba(255,255,255,0.3);
    border-top-color: #fff;
    border-radius: 50%;
    animation: spin 0.7s linear infinite;
    display: inline-block;
}

.spinner.large {
    width: 40px;
    height: 40px;
    border-width: 3px;
    border-color: rgba(88,166,255,0.3);
    border-top-color: var(--accent);
}

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

/* Progress */
.progress-indicator {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 16px;
    padding: 24px 0;
}

/* Limitations */
.limitations-card {
    background: rgba(210, 153, 34, 0.06);
    border: 1px solid rgba(210, 153, 34, 0.2);
    border-radius: 12px;
    padding: 24px;
    margin-top: 24px;
}

.limitations-card h3 {
    color: var(--warning);
    font-size: 1rem;
    margin-bottom: 12px;
}

.limitations-card ul {
    list-style: none;
    padding: 0;
}

.limitations-card li {
    position: relative;
    padding-left: 20px;
    font-size: 0.875rem;
    color: var(--text-secondary);
    margin-bottom: 6px;
}

.limitations-card li::before {
    content: '•';
    position: absolute;
    left: 4px;
    color: var(--warning);
}

.cta-box {
    margin-top: 16px;
    padding-top: 16px;
    border-top: 1px solid rgba(210, 153, 34, 0.15);
    text-align: center;
}

.cta-box p {
    font-size: 0.9rem;
    margin-bottom: 12px;
    color: var(--text);
}

/* Footer */
footer {
    text-align: center;
    margin-top: 40px;
    padding-top: 24px;
    border-top: 1px solid var(--border);
}

footer a {
    color: var(--accent);
    text-decoration: none;
}

footer a:hover {
    text-decoration: underline;
}

.footer-small {
    font-size: 0.75rem;
    color: var(--text-secondary);
    margin-top: 4px;
}

/* Responsive */
@media (max-width: 480px) {
    .container { padding: 20px 16px; }
    h1 { font-size: 1.6rem; }
    .logo { height: 32px; }
    .otp-input { font-size: 1.1rem; }
}