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

:root {
    --primary-color: #21a7eb;
    --primary-hover: #0d90dc;
    --background: #F5F5F7;
    --surface: #FFFFFF;
    --text-primary: #1D1D1F;
    --text-secondary: #86868B;
    --text-tertiary: #AEAEB2;
    --border-color: #E5E5E7;
    --border-focus: #21a7eb;
    --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.06);
    --shadow-md: 0 2px 8px rgba(0, 0, 0, 0.08);
    --shadow-lg: 0 4px 24px rgba(0, 0, 0, 0.10);
    --spacing-xs: 4px;
    --spacing-sm: 8px;
    --spacing-md: 12px;
    --spacing-lg: 16px;
    --spacing-xl: 20px;
    --radius-sm: 4px;
    --radius-md: 8px;
    --radius-lg: 12px;
    --font-sans: -apple-system, BlinkMacSystemFont, 'Inter', 'SF Pro Display', 'Segoe UI', Roboto, sans-serif;
}

body {
    font-family: var(--font-sans);
    background: var(--background);
    color: var(--text-primary);
    line-height: 1.5;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    font-size: 13px;
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: var(--spacing-xl);
}

.login-wrapper {
    width: 100%;
    max-width: 380px;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 24px;
}

.login-logo {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 8px;
}

.login-logo img {
    height: 36px;
    width: auto;
    display: block;
}

.login-tagline {
    font-size: 12px;
    color: var(--text-secondary);
    text-align: center;
    letter-spacing: 0.01em;
}

.login-card {
    width: 100%;
    background: var(--surface);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-lg);
    padding: 28px 28px 24px;
    display: flex;
    flex-direction: column;
    gap: 18px;
}

.login-card-title {
    font-size: 16px;
    font-weight: 600;
    color: var(--text-primary);
    letter-spacing: -0.01em;
}

.login-form {
    display: flex;
    flex-direction: column;
    gap: 14px;
}

.form-group {
    display: flex;
    flex-direction: column;
    gap: 5px;
}

.form-group label {
    font-size: 12px;
    font-weight: 500;
    color: var(--text-secondary);
    letter-spacing: 0.01em;
}

.input-wrapper {
    position: relative;
    display: flex;
    align-items: center;
}

.form-group input {
    width: 100%;
    height: 40px;
    padding: 0 var(--spacing-md);
    border: 1.5px solid var(--border-color);
    border-radius: var(--radius-md);
    font-family: var(--font-sans);
    font-size: 13px;
    color: var(--text-primary);
    background: var(--surface);
    outline: none;
    transition: border-color 0.15s ease, box-shadow 0.15s ease;
    -webkit-appearance: none;
}

.form-group input:focus {
    border-color: var(--border-focus);
    box-shadow: 0 0 0 3px rgba(33, 167, 235, 0.12);
}

.form-group input::placeholder {
    color: var(--text-tertiary);
}

.input-wrapper input[type="password"],
.input-wrapper input[type="text"] {
    padding-right: 40px;
}

.toggle-password {
    position: absolute;
    right: 10px;
    background: none;
    border: none;
    cursor: pointer;
    padding: 4px;
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--text-tertiary);
    transition: color 0.15s ease;
    line-height: 0;
}

.toggle-password:hover {
    color: var(--text-secondary);
}

.toggle-password svg {
    width: 16px;
    height: 16px;
    pointer-events: none;
}

.form-footer {
    display: flex;
    align-items: center;
    justify-content: flex-end;
    margin-top: -4px;
}

.forgot-link {
    font-size: 12px;
    color: var(--primary-color);
    text-decoration: none;
    transition: color 0.15s ease;
}

.forgot-link:hover {
    color: var(--primary-hover);
    text-decoration: underline;
}

.login-error {
    display: none;
    align-items: center;
    gap: var(--spacing-sm);
    background: #fff2f2;
    border: 1px solid #ffd6d6;
    border-radius: var(--radius-md);
    padding: 10px var(--spacing-md);
    font-size: 12px;
    color: #c0392b;
}

.login-error.visible {
    display: flex;
}

.login-error svg {
    flex-shrink: 0;
    width: 14px;
    height: 14px;
}

.btn-primary {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-sm);
    width: 100%;
    height: 40px;
    background: var(--primary-color);
    color: #fff;
    border: none;
    border-radius: var(--radius-md);
    font-family: var(--font-sans);
    font-size: 13px;
    font-weight: 600;
    cursor: pointer;
    transition: background 0.15s ease, transform 0.1s ease, box-shadow 0.15s ease;
    letter-spacing: 0.01em;
}

.btn-primary:hover {
    background: var(--primary-hover);
    box-shadow: 0 2px 8px rgba(33, 167, 235, 0.28);
}

.btn-primary:active {
    transform: scale(0.98);
}

.btn-primary:disabled {
    opacity: 0.55;
    cursor: not-allowed;
    transform: none;
}

.btn-primary .spinner {
    display: none;
    width: 14px;
    height: 14px;
    border: 2px solid rgba(255,255,255,0.4);
    border-top-color: #fff;
    border-radius: 50%;
    animation: spin 0.7s linear infinite;
}

.btn-primary.loading .spinner {
    display: block;
}

.btn-primary.loading .btn-label {
    opacity: 0.7;
}

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

.site-footer {
    padding: 12px var(--spacing-lg);
    border-top: 1px solid var(--border-color);
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    justify-content: center;
    gap: 6px 16px;
}

.site-footer-text,
.site-footer a {
    font-size: 12px;
    color: var(--text-tertiary);
    text-decoration: none;
    white-space: nowrap;
}

.site-footer a {
    display: inline-flex;
    align-items: center;
}

.site-footer a:hover { color: var(--text-secondary); text-decoration: underline; }
.site-footer-sep { font-size: 11px; color: var(--border-color); }

.site-footer-icon {
    width: 20px;
    height: 20px;
    object-fit: contain;
    margin-right: 5px;
}

@media (max-width: 768px) {
    .site-footer { flex-direction: column; gap: 4px; text-align: center; }
    .site-footer-sep { display: none; }
    .site-footer-text,
    .site-footer a { white-space: normal; }
}

@media (max-width: 480px) {
    body {
        align-items: flex-start;
        padding: 36px var(--spacing-lg) var(--spacing-xl);
    }
    .login-wrapper { gap: 20px; }
    .login-card { padding: 24px 18px 20px; }
    .login-logo img { height: 30px; }
}