:root {
    --transition: all 0.3s cubic-bezier(0.16, 1, 0.3, 1);
    --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.08);
    --shadow-md: 0 4px 16px rgba(0, 0, 0, 0.12);
    --border-radius-sm: 12px;
    --border-radius-lg: 18px;
    --spacing-sm: 12px;
    --spacing-md: 24px;
    --spacing-lg: 32px;
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    -webkit-tap-highlight-color: transparent;
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, sans-serif;
    color: var(--tg-theme-text-color);
    background: var(--tg-theme-bg-color);
    line-height: 1.5;
    padding: env(safe-area-inset-top) env(safe-area-inset-right) env(safe-area-inset-bottom) env(safe-area-inset-left);
    min-height: 100vh;
}

.container {
    max-width: 480px;
    margin: 0 auto;
    padding: var(--spacing-md);
}

.app-header {
    text-align: center;
    margin-bottom: var(--spacing-lg);
    padding-top: 10px;
}

.app-logo {
    width: 80px;
    height: 80px;
    border-radius: 24px;
    background: linear-gradient(135deg, var(--tg-theme-button-color), #4a6cf7);
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto var(--spacing-sm);
    box-shadow: var(--shadow-md);
    border: 2px solid rgba(255, 255, 255, 0.1);
}

.app-logo img {
    width: 48px;
    height: 48px;
    object-fit: contain;
}

h1 {
    font-size: 28px;
    font-weight: 700;
    margin-bottom: 8px;
    background: linear-gradient(to right, var(--tg-theme-text-color), var(--tg-theme-link-color, #4a6cf7));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.app-subtitle {
    color: var(--tg-theme-hint-color);
    font-size: 16px;
    margin-top: 4px;
}

.card {
    background: var(--tg-theme-secondary-bg-color);
    border-radius: var(--border-radius-lg);
    padding: var(--spacing-md);
    margin-bottom: var(--spacing-md);
    box-shadow: var(--shadow-sm);
    backdrop-filter: blur(12px);
    transition: var(--transition);
}

.card:active {
    transform: translateY(1px);
    box-shadow: 0 2px 6px rgba(0, 0, 0, 0.1);
}

.form-group {
    margin-bottom: var(--spacing-sm);
    text-align: left;
}

.form-label {
    display: block;
    margin-bottom: 6px;
    font-weight: 500;
    color: var(--tg-theme-text-color);
    font-size: 14px;
    opacity: 0.9;
}

.input-field {
    width: 100%;
    padding: 14px var(--spacing-sm);
    background: rgba(255, 255, 255, 0.08);
    border: 1px solid rgba(255, 255, 255, 0.12);
    border-radius: var(--border-radius-sm);
    color: var(--tg-theme-text-color);
    font-family: inherit;
    font-size: 16px;
    transition: var(--transition);
}

.input-field:focus {
    outline: none;
    border-color: var(--tg-theme-link-color, #4a6cf7);
    box-shadow: 0 0 0 3px rgba(74, 108, 247, 0.2);
    background: rgba(255, 255, 255, 0.12);
}

.select-field {
    appearance: none;
    background-image: url("data:image/svg+xml;charset=utf-8,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24'%3E%3Cpath fill='%23aaa' d='M7 10l5 5 5-5z'/%3E%3C/svg%3E");
    background-repeat: no-repeat;
    background-position: right 12px center;
    background-size: 16px;
}

.btn {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    width: 100%;
    padding: 16px;
    border: none;
    border-radius: var(--border-radius-sm);
    font-family: inherit;
    font-weight: 600;
    font-size: 16px;
    cursor: pointer;
    transition: var(--transition);
    position: relative;
    overflow: hidden;
    margin-top: 4px;
}

.btn::after {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.2), transparent);
    transition: left 0.7s;
}

.btn:active::after {
    left: 100%;
}

.btn-primary {
    background: var(--tg-theme-button-color);
    color: var(--tg-theme-button-text-color);
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
}

.btn-primary:active {
    transform: translateY(2px);
    box-shadow: 0 2px 6px rgba(0, 0, 0, 0.1);
}

.btn-secondary {
    background: rgba(255, 255, 255, 0.08);
    color: var(--tg-theme-text-color);
}

.btn-secondary:active {
    background: rgba(255, 255, 255, 0.15);
}

.btn-keycloak {
    background: linear-gradient(135deg, #4A90D9, #2E6EB5);
    color: white;
    box-shadow: 0 4px 12px rgba(74, 144, 217, 0.3);
}

.btn-keycloak:active {
    transform: translateY(2px);
    box-shadow: 0 2px 6px rgba(74, 144, 217, 0.2);
}

.btn-icon {
    font-size: 18px;
    display: flex;
    align-items: center;
}

.oauth-divider {
    display: flex;
    align-items: center;
    text-align: center;
    margin: var(--spacing-md) 0;
    color: var(--tg-theme-hint-color);
    font-size: 14px;
}

.oauth-divider::before,
.oauth-divider::after {
    content: '';
    flex: 1;
    border-bottom: 1px solid rgba(255, 255, 255, 0.12);
}

.oauth-divider span {
    padding: 0 var(--spacing-sm);
}

.oauth-buttons {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-sm);
    margin-top: var(--spacing-md);
}

.choice-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: var(--spacing-sm);
    margin: var(--spacing-lg) 0;
}

.choice-card {
    background: linear-gradient(135deg, var(--tg-theme-secondary-bg-color), rgba(255, 255, 255, 0.05));
    border: 1px solid rgba(255, 255, 255, 0.08);
    border-radius: var(--border-radius-lg);
    padding: var(--spacing-md);
    text-align: left;
    cursor: pointer;
    transition: var(--transition);
    position: relative;
    overflow: hidden;
}

.choice-card:hover {
    transform: translateY(-2px);
    border-color: var(--tg-theme-link-color, rgba(74, 108, 247, 0.4));
}

.choice-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 4px;
    height: 100%;
    background: var(--tg-theme-link-color, #4a6cf7);
    transform: scaleY(0);
    transform-origin: bottom;
    transition: transform 0.4s ease;
}

.choice-card:hover::before {
    transform: scaleY(1);
}

.choice-title {
    font-size: 20px;
    font-weight: 700;
    margin-bottom: 4px;
    display: flex;
    align-items: center;
    gap: 10px;
}

.choice-desc {
    color: var(--tg-theme-hint-color);
    font-size: 14px;
    line-height: 1.4;
}

.alert {
    border-radius: var(--border-radius-sm);
    padding: 14px var(--spacing-sm);
    margin: var(--spacing-sm) 0;
    font-size: 14px;
    display: flex;
    align-items: center;
    gap: 10px;
    animation: slideIn 0.4s ease;
}

@keyframes slideIn {
    from {
        opacity: 0;
        transform: translateY(-10px);
    }

    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.alert.success {
    background: rgba(34, 197, 94, 0.15);
    border: 1px solid rgba(34, 197, 94, 0.3);
    color: #16a34a;
}

.alert.error {
    background: rgba(239, 68, 68, 0.15);
    border: 1px solid rgba(239, 68, 68, 0.3);
    color: #dc2626;
}

.alert.info {
    background: rgba(59, 130, 246, 0.15);
    border: 1px solid rgba(59, 130, 246, 0.3);
    color: #2563eb;
}

.alert-icon {
    font-size: 18px;
    flex-shrink: 0;
}

.form-actions {
    display: flex;
    flex-direction: column;
    gap: 12px;
    margin-top: 8px;
}

.hidden {
    display: none !important;
}

.page-transition {
    opacity: 0;
    transform: translateY(10px);
    transition: var(--transition);
}

.page-transition.active {
    opacity: 1;
    transform: translateY(0);
}

.logout-container {
    margin-top: var(--spacing-md);
    padding-top: var(--spacing-md);
    border-top: 1px solid rgba(255, 255, 255, 0.08);
}

/* Loading spinner for button states */
.spinner {
    width: 20px;
    height: 20px;
    border: 2px solid rgba(255, 255, 255, 0.3);
    border-top-color: white;
    border-radius: 50%;
    animation: spin 0.8s linear infinite;
    display: inline-block;
    margin-right: 8px;
}

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

@media (prefers-reduced-motion: no-preference) {

    .btn,
    .choice-card,
    .input-field {
        transition: var(--transition);
    }
}

@supports (backdrop-filter: blur(12px)) {
    .card {
        backdrop-filter: blur(12px);
        background: rgba(30, 30, 30, 0.6);
    }
}