/* ===== CSS Variables ===== */
:root {
    --primary-color: #6366f1;
    --primary-hover: #4f46e5;
    --primary-light: #e0e7ff;
    --secondary-color: #64748b;
    --secondary-hover: #475569;
    --success-color: #10b981;
    --warning-color: #f59e0b;
    --danger-color: #ef4444;
    --background-color: #f8fafc;
    --card-background: #ffffff;
    --text-primary: #1e293b;
    --text-secondary: #64748b;
    --text-muted: #94a3b8;
    --border-color: #e2e8f0;
    --border-radius: 12px;
    --border-radius-sm: 8px;
    --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.05);
    --shadow: 0 4px 6px -1px rgb(0 0 0 / 0.1), 0 2px 4px -2px rgb(0 0 0 / 0.1);
    --shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 0.1), 0 4px 6px -4px rgb(0 0 0 / 0.1);
    --transition: all 0.2s ease;
    --font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
}

/* ===== Reset & Base Styles ===== */
*,
*::before,
*::after {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

html {
    font-size: 16px;
    scroll-behavior: smooth;
}

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

/* ===== App Container ===== */
.app-container {
    display: flex;
    flex-direction: column;
    min-height: 100vh;
}

/* ===== Header ===== */
.header {
    background: linear-gradient(135deg, var(--primary-color) 0%, #8b5cf6 100%);
    color: white;
    padding: 2rem 1rem;
    text-align: center;
}

.header-content {
    max-width: 800px;
    margin: 0 auto;
}

.logo {
    font-size: 2rem;
    font-weight: 700;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
    margin-bottom: 0.5rem;
}

.logo-icon {
    font-size: 2.5rem;
}

.tagline {
    font-size: 1.1rem;
    opacity: 0.9;
    font-weight: 300;
}

/* ===== Main Content ===== */
.main-content {
    flex: 1;
    max-width: 900px;
    width: 100%;
    margin: 0 auto;
    padding: 2rem 1rem;
    display: flex;
    flex-direction: column;
    gap: 2rem;
}

/* ===== Cards ===== */
.card {
    background: var(--card-background);
    border-radius: var(--border-radius);
    padding: 1.5rem;
    box-shadow: var(--shadow);
    border: 1px solid var(--border-color);
}

.card h2 {
    font-size: 1.25rem;
    font-weight: 600;
    margin-bottom: 1rem;
    color: var(--text-primary);
}

.card h3 {
    font-size: 1rem;
    font-weight: 600;
    margin-top: 1.5rem;
    margin-bottom: 1rem;
    color: var(--text-primary);
}

.section-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 1rem;
}

.section-header h2 {
    margin-bottom: 0;
}

.section-description {
    color: var(--text-secondary);
    font-size: 0.9rem;
    margin-bottom: 1.5rem;
}

/* ===== Form Elements ===== */
.form-group {
    margin-bottom: 1rem;
}

.form-group label {
    display: block;
    font-size: 0.875rem;
    font-weight: 500;
    color: var(--text-secondary);
    margin-bottom: 0.5rem;
}

.select-input,
.textarea-input {
    width: 100%;
    padding: 0.75rem 1rem;
    font-size: 1rem;
    font-family: var(--font-family);
    border: 2px solid var(--border-color);
    border-radius: var(--border-radius-sm);
    background-color: var(--card-background);
    color: var(--text-primary);
    transition: var(--transition);
    appearance: none;
}

.select-input {
    background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' fill='none' viewBox='0 0 24 24' stroke='%2364748b'%3E%3Cpath stroke-linecap='round' stroke-linejoin='round' stroke-width='2' d='M19 9l-7 7-7-7'%3E%3C/path%3E%3C/svg%3E");
    background-repeat: no-repeat;
    background-position: right 0.75rem center;
    background-size: 1.25rem;
    padding-right: 2.5rem;
    cursor: pointer;
}

.select-input:focus,
.textarea-input:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px var(--primary-light);
}

.textarea-input {
    resize: vertical;
    min-height: 80px;
}

/* ===== Buttons ===== */
.button-group {
    display: flex;
    gap: 0.75rem;
    margin-top: 1.5rem;
}

.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
    padding: 0.75rem 1.5rem;
    font-size: 1rem;
    font-weight: 500;
    font-family: var(--font-family);
    border: none;
    border-radius: var(--border-radius-sm);
    cursor: pointer;
    transition: var(--transition);
    text-decoration: none;
}

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

.btn-primary:hover {
    background-color: var(--primary-hover);
    transform: translateY(-1px);
    box-shadow: var(--shadow);
}

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

.btn-secondary:hover {
    background-color: var(--secondary-hover);
    transform: translateY(-1px);
    box-shadow: var(--shadow);
}

.btn-outline {
    background-color: transparent;
    color: var(--secondary-color);
    border: 2px solid var(--border-color);
}

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

.btn-small {
    padding: 0.5rem 1rem;
    font-size: 0.875rem;
}

.btn-icon {
    font-size: 1.1rem;
}

.btn-icon-only {
    background: none;
    border: none;
    cursor: pointer;
    font-size: 1.25rem;
    padding: 0.25rem;
    opacity: 0.7;
    transition: var(--transition);
}

.btn-icon-only:hover {
    opacity: 1;
    transform: scale(1.1);
}

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

.btn-danger:hover {
    background-color: #dc2626;
}

/* ===== Prompt Display ===== */
.prompt-display {
    margin-top: 1.5rem;
    padding: 1.25rem;
    background: linear-gradient(135deg, #f0f9ff 0%, #e0f2fe 100%);
    border-radius: var(--border-radius-sm);
    border: 2px solid #bae6fd;
    animation: fadeIn 0.3s ease;
}

.prompt-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 0.75rem;
}

.prompt-label {
    font-size: 0.875rem;
    font-weight: 600;
    color: var(--primary-color);
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

.prompt-text {
    font-size: 1.1rem;
    line-height: 1.7;
    color: var(--text-primary);
}

.prompt-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
    margin-top: 1rem;
}

.tag {
    display: inline-block;
    padding: 0.25rem 0.75rem;
    font-size: 0.75rem;
    font-weight: 500;
    background-color: var(--primary-light);
    color: var(--primary-color);
    border-radius: 9999px;
}

/* ===== History & Favorites Lists ===== */
.history-list,
.favorites-list,
.user-prompts-list {
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
}

.history-item,
.favorite-item,
.user-prompt-item {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    gap: 1rem;
    padding: 1rem;
    background-color: var(--background-color);
    border-radius: var(--border-radius-sm);
    border: 1px solid var(--border-color);
    transition: var(--transition);
}

.history-item:hover,
.favorite-item:hover,
.user-prompt-item:hover {
    border-color: var(--primary-color);
}

.item-content {
    flex: 1;
}

.item-text {
    font-size: 0.95rem;
    color: var(--text-primary);
    margin-bottom: 0.5rem;
}

.item-meta {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
}

.item-actions {
    display: flex;
    gap: 0.5rem;
    flex-shrink: 0;
}

.action-btn {
    background: none;
    border: none;
    cursor: pointer;
    font-size: 1.25rem;
    padding: 0.25rem;
    opacity: 0.6;
    transition: var(--transition);
}

.action-btn:hover {
    opacity: 1;
    transform: scale(1.15);
}

.action-btn.favorited {
    opacity: 1;
    color: var(--warning-color);
}

/* ===== Empty State ===== */
.empty-state {
    text-align: center;
    padding: 2rem;
    color: var(--text-muted);
    font-style: italic;
}

/* ===== Hidden Utility ===== */
.hidden {
    display: none !important;
}

/* ===== Footer ===== */
.footer {
    background-color: var(--text-primary);
    color: white;
    padding: 1.5rem 1rem;
    text-align: center;
    margin-top: auto;
}

.footer-content {
    max-width: 800px;
    margin: 0 auto;
}

.powered-by {
    font-size: 1rem;
    margin-bottom: 0.5rem;
}

.powered-by a {
    color: #93c5fd;
    text-decoration: none;
    font-weight: 500;
    transition: var(--transition);
}

.powered-by a:hover {
    color: white;
    text-decoration: underline;
}

.copyright {
    font-size: 0.875rem;
    color: var(--text-muted);
}

/* ===== Toast Notification ===== */
.toast {
    position: fixed;
    bottom: 2rem;
    left: 50%;
    transform: translateX(-50%);
    background-color: var(--text-primary);
    color: white;
    padding: 0.75rem 1.5rem;
    border-radius: var(--border-radius-sm);
    box-shadow: var(--shadow-lg);
    z-index: 1000;
    animation: slideUp 0.3s ease;
}

.toast.hidden {
    display: none;
}

/* ===== Animations ===== */
@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(-10px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@keyframes slideUp {
    from {
        opacity: 0;
        transform: translate(-50%, 20px);
    }
    to {
        opacity: 1;
        transform: translate(-50%, 0);
    }
}

/* ===== Responsive Design ===== */
@media (max-width: 768px) {
    .header {
        padding: 1.5rem 1rem;
    }

    .logo {
        font-size: 1.5rem;
        flex-direction: column;
        gap: 0.25rem;
    }

    .logo-icon {
        font-size: 2rem;
    }

    .tagline {
        font-size: 0.95rem;
    }

    .main-content {
        padding: 1rem;
        gap: 1.5rem;
    }

    .card {
        padding: 1.25rem;
    }

    .button-group {
        flex-direction: column;
    }

    .btn {
        width: 100%;
    }

    .section-header {
        flex-direction: column;
        align-items: flex-start;
        gap: 0.75rem;
    }

    .history-item,
    .favorite-item,
    .user-prompt-item {
        flex-direction: column;
    }

    .item-actions {
        align-self: flex-end;
    }

    .prompt-header {
        flex-direction: column;
        align-items: flex-start;
        gap: 0.5rem;
    }
}

@media (max-width: 480px) {
    html {
        font-size: 14px;
    }

    .card h2 {
        font-size: 1.1rem;
    }

    .prompt-text {
        font-size: 1rem;
    }
}

/* ===== Accessibility ===== */
@media (prefers-reduced-motion: reduce) {
    *,
    *::before,
    *::after {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
    }
}

/* Focus visible for keyboard navigation */
.btn:focus-visible,
.select-input:focus-visible,
.textarea-input:focus-visible,
.action-btn:focus-visible {
    outline: 2px solid var(--primary-color);
    outline-offset: 2px;
}

/* ===== Scrollbar Styling ===== */
::-webkit-scrollbar {
    width: 8px;
    height: 8px;
}

::-webkit-scrollbar-track {
    background: var(--background-color);
}

::-webkit-scrollbar-thumb {
    background: var(--text-muted);
    border-radius: 4px;
}

::-webkit-scrollbar-thumb:hover {
    background: var(--secondary-color);
}