:root {
    --bg-primary: #fafafa;
    --bg-secondary: #ffffff;
    --bg-tertiary: #f5f5f5;
    --text-primary: #1a1a1a;
    --text-secondary: #666666;
    --text-tertiary: #999999;
    --border: #e0e0e0;
    --accent: #152e47;
    --accent-hover: #0f1f30;
    --success: #10b981;
    --success-hover: #059669;
    --danger: #ef4444;
    --danger-hover: #dc2626;
    --shadow: rgba(0, 0, 0, 0.05);
    --shadow-lg: rgba(0, 0, 0, 0.1);
}

[data-theme="dark"] {
    --bg-primary: #0f0f0f;
    --bg-secondary: #1a1a1a;
    --bg-tertiary: #262626;
    --text-primary: #f5f5f5;
    --text-secondary: #a3a3a3;
    --text-tertiary: #737373;
    --border: #333333;
    --accent: #2a4d6e;
    --accent-hover: #1f3a52;
    --success: #34d399;
    --success-hover: #10b981;
    --danger: #f87171;
    --danger-hover: #ef4444;
    --shadow: rgba(0, 0, 0, 0.3);
    --shadow-lg: rgba(0, 0, 0, 0.5);
}

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

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', sans-serif;
    background: var(--bg-primary);
    color: var(--text-primary);
    line-height: 1.6;
    transition: background 0.3s ease, color 0.3s ease;
    min-height: 100vh;
}

.app-header {
    background: var(--bg-secondary);
    border-bottom: 1px solid var(--border);
    padding: 16px 20px;
    display: grid;
    grid-template-columns: 40px 1fr 40px;
    align-items: center;
    gap: 12px;
    position: sticky;
    top: 0;
    z-index: 100;
    box-shadow: 0 1px 3px var(--shadow);
}

.app-header h1 {
    font-size: 1.25rem;
    font-weight: 600;
    color: var(--text-primary);
    margin: 0;
    text-align: center;
    justify-self: center;
}

.header-right {
    display: flex;
    align-items: center;
    gap: 8px;
    justify-self: end;
}

.user-info {
    font-size: 0.875rem;
    color: var(--text-secondary);
    white-space: nowrap;
}

.btn-icon-only {
    width: 40px;
    height: 40px;
    padding: 0;
    display: flex;
    align-items: center;
    justify-content: center;
    background: transparent;
    border: 1px solid var(--border);
    border-radius: 8px;
    cursor: pointer;
    transition: all 0.2s ease;
    flex-shrink: 0;
}

.btn-icon-only svg {
    color: var(--text-secondary);
    transition: color 0.2s ease;
}

.btn-icon-only:hover {
    background: var(--bg-tertiary);
    border-color: var(--accent);
}

.btn-icon-only:hover svg {
    color: var(--accent);
}

#theme-toggle {
    background: rgba(222, 184, 135, 0.15);
}

#theme-toggle:hover {
    background: rgba(222, 184, 135, 0.25);
    border-color: rgb(222, 184, 135);
    box-shadow: 0 0 12px rgba(222, 184, 135, 0.4);
}

#theme-toggle:hover svg {
    color: rgb(184, 134, 11);
}

#theme-toggle:active {
    box-shadow: 0 0 16px rgba(222, 184, 135, 0.6);
}

.logout-btn {
    background: rgba(239, 68, 68, 0.12);
}

.logout-btn:hover {
    background: rgba(239, 68, 68, 0.2);
    border-color: var(--danger);
    box-shadow: 0 0 12px rgba(239, 68, 68, 0.4);
}

.logout-btn:hover svg {
    color: var(--danger);
}

.logout-btn:active {
    box-shadow: 0 0 16px rgba(239, 68, 68, 0.6);
}

.user-menu {
    position: relative;
    display: flex;
    align-items: center;
}

.user-btn {
    background: rgba(21, 46, 71, 0.08);
}

.user-btn:hover {
    background: rgba(21, 46, 71, 0.15);
    border-color: var(--accent);
    box-shadow: 0 0 12px rgba(21, 46, 71, 0.3);
}

.user-btn:hover svg {
    color: var(--accent);
}

.user-btn:active {
    box-shadow: 0 0 16px rgba(21, 46, 71, 0.5);
}

.user-tooltip {
    position: absolute;
    top: calc(100% + 8px);
    right: 0;
    background: var(--bg-secondary);
    border: 1px solid var(--border);
    border-radius: 8px;
    padding: 8px 12px;
    font-size: 0.875rem;
    color: var(--text-primary);
    white-space: nowrap;
    box-shadow: 0 4px 12px var(--shadow-lg);
    z-index: 1000;
    pointer-events: none;
}

.user-tooltip::before {
    content: '';
    position: absolute;
    top: -6px;
    right: 12px;
    width: 12px;
    height: 12px;
    background: var(--bg-secondary);
    border-left: 1px solid var(--border);
    border-top: 1px solid var(--border);
    transform: rotate(45deg);
}

@media (hover: hover) {
    .user-menu:hover .user-tooltip {
        display: block !important;
    }
}

.user-tooltip.show {
    display: block !important;
}

.btn-text {
    background: transparent;
    border: none;
    color: var(--text-secondary);
    font-size: 0.875rem;
    padding: 8px 12px;
    cursor: pointer;
    transition: color 0.2s ease;
    font-weight: 500;
}

.btn-text:hover {
    color: var(--text-primary);
}

.container {
    max-width: 640px;
    margin: 0 auto;
    padding: 24px 16px;
}

#login-screen {
    max-width: 400px;
    margin: 0 auto;
    padding: 60px 16px;
}

#login-screen .card {
    text-align: left;
}

#login-screen h2 {
    text-align: center;
    margin-bottom: 8px;
}

#login-screen p {
    text-align: center;
    font-size: 0.875rem;
    color: var(--text-secondary);
    margin-bottom: 24px;
}

.card {
    background: var(--bg-secondary);
    border: 1px solid var(--border);
    border-radius: 12px;
    padding: 20px;
    margin-bottom: 16px;
    transition: all 0.3s ease;
}

.card h2 {
    font-size: 0.875rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    color: var(--text-tertiary);
    margin-bottom: 16px;
}

.row {
    display: flex;
    gap: 12px;
    margin-bottom: 12px;
    align-items: flex-end;
    justify-content: center;
}

.lang-select {
    flex: 1;
    max-width: 200px;
}

.swap-btn-container {
    flex: 0 0 auto;
    display: flex;
    align-items: flex-end;
}

.swap-btn {
    width: auto;
    padding: 12px 16px;
    font-size: 1.2rem;
}

label {
    display: block;
    font-size: 0.875rem;
    font-weight: 500;
    color: var(--text-secondary);
    margin-bottom: 6px;
}

select,
input[type="text"],
input[type="password"] {
    width: 100%;
    padding: 12px 14px;
    font-size: 0.9375rem;
    border: 1px solid var(--border);
    border-radius: 8px;
    background: var(--bg-primary);
    color: var(--text-primary);
    appearance: none;
    -webkit-appearance: none;
    transition: all 0.2s ease;
}

select:focus,
input:focus {
    outline: none;
    border-color: var(--accent);
    box-shadow: 0 0 0 3px rgba(21, 46, 71, 0.15);
}

button {
    width: 100%;
    padding: 12px 16px;
    font-size: 0.9375rem;
    font-weight: 500;
    border: none;
    border-radius: 8px;
    cursor: pointer;
    transition: all 0.2s ease;
}

.btn-primary {
    background: var(--accent);
    color: #ffffff;
}

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

.btn-primary:disabled {
    background: var(--text-tertiary);
    cursor: not-allowed;
    opacity: 0.5;
}

.btn-success {
    background: var(--success);
    color: #ffffff;
}

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

.btn-success:disabled {
    background: var(--text-tertiary);
    cursor: not-allowed;
    opacity: 0.5;
}

.btn-secondary {
    background: var(--bg-tertiary);
    color: var(--text-primary);
    border: 1px solid var(--border);
}

.btn-secondary:hover {
    background: var(--border);
}

.btn-outline {
    background: transparent;
    border: 1px solid var(--border);
    color: var(--text-secondary);
}

.btn-outline:hover {
    border-color: var(--accent);
    color: var(--accent);
    background: rgba(21, 46, 71, 0.05);
}

.btn-danger {
    background: var(--danger);
    color: #ffffff;
}

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

.results {
    margin-top: 8px;
}

.wordclass {
    font-weight: 600;
    font-size: 0.875rem;
    color: var(--text-primary);
    background: var(--bg-tertiary);
    padding: 8px 12px;
    border-radius: 6px;
    margin: 16px 0 8px 0;
}

.wordclass:first-child {
    margin-top: 0;
}

.translation-item {
    display: flex;
    align-items: flex-start;
    padding: 12px 0;
    border-bottom: 1px solid var(--border);
}

.translation-item:last-child {
    border-bottom: none;
}

.translation-item input[type="radio"] {
    width: 20px;
    height: 20px;
    margin-right: 12px;
    margin-top: 2px;
    flex-shrink: 0;
    accent-color: var(--accent);
}

.translation-content {
    flex: 1;
}

.translation-text {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
    align-items: center;
    cursor: pointer;
}

.source {
    font-weight: 500;
    color: var(--text-primary);
}

.arrow {
    color: var(--text-tertiary);
}

.target {
    color: var(--success);
    font-weight: 500;
}

.examples-toggle {
    font-size: 0.875rem;
    color: var(--accent);
    background: none;
    border: none;
    padding: 6px 0;
    cursor: pointer;
    text-align: left;
    width: auto;
    font-weight: 500;
}

.examples-toggle:hover {
    color: var(--accent-hover);
}

.examples-list {
    display: none;
    margin-top: 8px;
    padding-left: 12px;
    border-left: 2px solid var(--border);
}

.examples-list.open {
    display: block;
}

.example-item {
    display: flex;
    align-items: flex-start;
    padding: 8px 0;
    font-size: 0.875rem;
    color: var(--text-secondary);
}

.example-item input[type="checkbox"] {
    width: 18px;
    height: 18px;
    margin-right: 10px;
    flex-shrink: 0;
    accent-color: var(--accent);
}

.status {
    text-align: center;
    padding: 12px 16px;
    border-radius: 8px;
    font-size: 0.875rem;
    margin: 16px 0;
    font-weight: 500;
}

.status.error {
    background: rgba(239, 68, 68, 0.1);
    color: var(--danger);
    border: 1px solid rgba(239, 68, 68, 0.2);
}

.status.success {
    background: rgba(16, 185, 129, 0.1);
    color: var(--success);
    border: 1px solid rgba(16, 185, 129, 0.2);
}

.status.info {
    background: rgba(21, 46, 71, 0.1);
    color: var(--accent);
    border: 1px solid rgba(21, 46, 71, 0.2);
}

.hidden {
    display: none !important;
}

.loading {
    display: inline-block;
    width: 16px;
    height: 16px;
    border: 2px solid currentColor;
    border-top-color: transparent;
    border-radius: 50%;
    animation: spin 0.8s linear infinite;
    vertical-align: middle;
    margin-right: 8px;
}

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

#anki-section {
    display: none;
}

#anki-section.visible {
    display: block;
}

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

.deck-row {
    display: flex;
    gap: 8px;
    align-items: center;
    margin-bottom: 8px;
}

.deck-row select {
    flex: 1;
}

.deck-row .btn-icon {
    width: 44px;
    padding: 10px;
    flex-shrink: 0;
}

.btn-icon {
    display: flex;
    align-items: center;
    justify-content: center;
}

.deck-actions {
    display: flex;
    gap: 8px;
    margin-top: 8px;
}

.deck-actions button {
    flex: 1;
    padding: 10px;
    font-size: 0.875rem;
}

.modal-overlay {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0, 0, 0, 0.5);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 1000;
    backdrop-filter: blur(4px);
}

.modal-overlay.hidden {
    display: none;
}

.modal {
    background: var(--bg-secondary);
    border: 1px solid var(--border);
    border-radius: 16px;
    padding: 24px;
    width: 90%;
    max-width: 400px;
    box-shadow: 0 20px 40px var(--shadow-lg);
}

.modal h3 {
    margin-bottom: 16px;
    color: var(--text-primary);
    font-size: 1.125rem;
    font-weight: 600;
}

.modal p {
    color: var(--text-secondary);
    font-size: 0.9375rem;
    margin-bottom: 20px;
    line-height: 1.5;
}

.modal-buttons {
    display: flex;
    gap: 12px;
    margin-top: 20px;
}

.modal-buttons button {
    flex: 1;
}

#main-app {
    max-width: 640px;
    margin: 0 auto;
    padding: 24px 16px;
}

@media (max-width: 640px) {
    .app-header {
        padding: 12px 16px;
        grid-template-columns: 40px 1fr auto;
    }

    .app-header h1 {
        font-size: 1.125rem;
    }

    .user-info {
        display: none;
    }

    #main-app {
        padding: 16px 12px;
    }

    .card {
        padding: 16px;
    }

    .modal {
        padding: 20px;
    }
}

@media (max-width: 400px) {
    .row {
        flex-direction: column;
        gap: 8px;
        align-items: center;
    }

    .lang-select {
        max-width: 100%;
        width: 100%;
    }

    .swap-btn-container {
        order: 2;
        width: auto;
    }

    .deck-actions {
        flex-direction: column;
    }

    .modal-buttons {
        flex-direction: column;
    }
}