/* ========================================
   AI Regex Generator — Styles
   Warm dark theme with amber & red accents
   ======================================== */

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

:root {
    --primary: #F59E0B;
    --primary-hover: #FBBF24;
    --primary-glow: rgba(245, 158, 11, 0.25);
    --accent: #EF4444;
    --accent-hover: #F87171;
    --accent-glow: rgba(239, 68, 68, 0.2);
    --success: #22C55E;
    --info: #3B82F6;

    --bg-root: #0F172A;
    --bg-surface: #1E293B;
    --bg-elevated: #334155;
    --bg-card: rgba(30, 41, 59, 0.7);
    --bg-hover: rgba(245, 158, 11, 0.08);

    --border: rgba(255, 255, 255, 0.08);
    --border-active: rgba(245, 158, 11, 0.4);

    --text-primary: #F1F5F9;
    --text-secondary: #94A3B8;
    --text-tertiary: #64748B;
    --text-match: #F59E0B;

    --radius-sm: 6px;
    --radius-md: 10px;
    --radius-lg: 14px;
    --radius-xl: 20px;

    --font-body: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    --font-mono: 'JetBrains Mono', 'Fira Code', 'SF Mono', monospace;

    --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.3);
    --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.4);
    --shadow-lg: 0 8px 32px rgba(0, 0, 0, 0.5);
    --shadow-glow: 0 0 24px var(--primary-glow);

    --transition-fast: 150ms ease;
    --transition-base: 250ms ease;
    --transition-smooth: 350ms cubic-bezier(0.4, 0, 0.2, 1);
}

html {
    font-size: 15px;
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-body);
    background: var(--bg-root);
    color: var(--text-primary);
    min-height: 100vh;
    -webkit-font-smoothing: antialiased;
}

/* ---------- Glass ---------- */
.glass {
    background: var(--bg-card);
    backdrop-filter: blur(16px);
    -webkit-backdrop-filter: blur(16px);
    border: 1px solid var(--border);
}

/* ---------- Header ---------- */
.header {
    position: sticky;
    top: 0;
    z-index: 100;
    background: rgba(15, 23, 42, 0.85);
    backdrop-filter: blur(12px);
    border-bottom: 1px solid var(--border);
}

.header-content {
    max-width: 900px;
    margin: 0 auto;
    padding: 14px 24px;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.logo {
    display: flex;
    align-items: center;
    gap: 12px;
}

.logo h1 {
    font-size: 1.15rem;
    font-weight: 700;
    color: var(--text-primary);
}

.gradient-text {
    background: linear-gradient(135deg, var(--primary), var(--accent));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.header-actions {
    display: flex;
    gap: 8px;
}

.icon-btn {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 36px;
    height: 36px;
    border: 1px solid var(--border);
    background: transparent;
    color: var(--text-secondary);
    border-radius: var(--radius-sm);
    cursor: pointer;
    transition: all var(--transition-fast);
    position: relative;
}

.icon-btn:hover {
    color: var(--text-primary);
    border-color: var(--border-active);
    background: var(--bg-hover);
}

.icon-btn.small {
    width: 30px;
    height: 30px;
}

.badge {
    position: absolute;
    top: -4px;
    right: -4px;
    min-width: 16px;
    height: 16px;
    padding: 0 4px;
    background: var(--accent);
    color: #fff;
    font-size: 0.6rem;
    font-weight: 700;
    border-radius: 8px;
    display: flex;
    align-items: center;
    justify-content: center;
}

/* ---------- Main ---------- */
.main {
    max-width: 900px;
    margin: 0 auto;
    padding: 32px 24px 60px;
}

/* ---------- Input Section ---------- */
.input-section {
    margin-bottom: 32px;
}

.input-card {
    border-radius: var(--radius-lg);
    padding: 24px;
    margin-bottom: 16px;
}

.input-label {
    display: block;
    font-size: 0.85rem;
    font-weight: 600;
    color: var(--text-secondary);
    margin-bottom: 12px;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.input-wrapper {
    display: flex;
    gap: 12px;
    align-items: flex-end;
}

.natural-input {
    flex: 1;
    padding: 14px 16px;
    background: var(--bg-surface);
    border: 1px solid var(--border);
    border-radius: var(--radius-md);
    color: var(--text-primary);
    font-family: var(--font-body);
    font-size: 0.95rem;
    line-height: 1.5;
    resize: vertical;
    transition: border-color var(--transition-fast);
}

.natural-input:focus {
    outline: none;
    border-color: var(--primary);
    box-shadow: 0 0 0 3px var(--primary-glow);
}

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

.generate-btn {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 14px 24px;
    background: linear-gradient(135deg, var(--primary), var(--accent));
    color: #fff;
    border: none;
    border-radius: var(--radius-md);
    font-family: var(--font-body);
    font-size: 0.9rem;
    font-weight: 600;
    cursor: pointer;
    transition: all var(--transition-base);
    white-space: nowrap;
    flex-shrink: 0;
}

.generate-btn:hover {
    transform: translateY(-1px);
    box-shadow: var(--shadow-glow);
}

.generate-btn:active {
    transform: translateY(0);
}

.input-hint {
    margin-top: 10px;
    font-size: 0.75rem;
    color: var(--text-tertiary);
}

/* ---------- Presets ---------- */
.presets {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
}

.preset-chip {
    padding: 8px 16px;
    border: 1px solid var(--border);
    background: var(--bg-card);
    backdrop-filter: blur(8px);
    color: var(--text-secondary);
    font-family: var(--font-body);
    font-size: 0.8rem;
    font-weight: 500;
    border-radius: var(--radius-xl);
    cursor: pointer;
    transition: all var(--transition-fast);
}

.preset-chip:hover {
    color: var(--text-primary);
    border-color: var(--border-active);
    background: var(--bg-hover);
    transform: translateY(-1px);
}

/* ---------- Results ---------- */
.results-section[hidden] {
    display: none;
}

.result-card {
    border-radius: var(--radius-lg);
    padding: 20px 24px;
    margin-bottom: 16px;
    animation: slideUp var(--transition-smooth);
}

.result-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-bottom: 16px;
}

.result-header h2 {
    font-size: 0.9rem;
    font-weight: 600;
    color: var(--text-secondary);
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

/* ---------- Regex Display ---------- */
.regex-display {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 16px;
    background: var(--bg-root);
    border-radius: var(--radius-md);
    border: 1px solid var(--border);
}

.regex-output {
    flex: 1;
    font-family: var(--font-mono);
    font-size: 1rem;
    color: var(--primary);
    word-break: break-all;
    line-height: 1.5;
}

.copy-actions {
    display: flex;
    gap: 4px;
    flex-shrink: 0;
}

.copy-btn {
    padding: 6px 10px;
    border: 1px solid var(--border);
    background: transparent;
    color: var(--text-tertiary);
    font-family: var(--font-mono);
    font-size: 0.7rem;
    font-weight: 500;
    border-radius: var(--radius-sm);
    cursor: pointer;
    transition: all var(--transition-fast);
}

.copy-btn:hover {
    color: var(--primary);
    border-color: var(--border-active);
    background: var(--bg-hover);
}

/* ---------- Flag Toggles ---------- */
.flag-toggles {
    display: flex;
    gap: 4px;
}

.flag-btn {
    width: 28px;
    height: 28px;
    border: 1px solid var(--border);
    background: transparent;
    color: var(--text-tertiary);
    font-family: var(--font-mono);
    font-size: 0.8rem;
    font-weight: 600;
    border-radius: var(--radius-sm);
    cursor: pointer;
    transition: all var(--transition-fast);
}

.flag-btn:hover {
    color: var(--text-secondary);
    border-color: var(--border-active);
}

.flag-btn.active {
    background: rgba(245, 158, 11, 0.15);
    color: var(--primary);
    border-color: var(--primary);
}

/* ---------- Railroad Diagram ---------- */
.railroad-container {
    overflow-x: auto;
    padding: 8px 0;
}

.railroad-container svg {
    display: block;
    margin: 0 auto;
}

.railroad-container svg text {
    font-family: var(--font-mono);
    font-size: 12px;
    fill: var(--text-primary);
}

.railroad-container svg .railroad-path {
    stroke: var(--primary);
    stroke-width: 2;
    fill: none;
}

.railroad-container svg .railroad-node {
    fill: var(--bg-elevated);
    stroke: var(--border-active);
    stroke-width: 1.5;
    rx: 6;
}

.railroad-container svg .railroad-terminal {
    fill: rgba(245, 158, 11, 0.1);
    stroke: var(--primary);
    stroke-width: 1.5;
    rx: 12;
}

/* ---------- Explanation ---------- */
.explanation {
    display: flex;
    flex-direction: column;
    gap: 8px;
}

.explanation-item {
    display: flex;
    gap: 10px;
    padding: 10px 14px;
    background: var(--bg-surface);
    border-radius: var(--radius-sm);
    border-left: 3px solid var(--primary);
}

.explanation-item code {
    font-family: var(--font-mono);
    color: var(--primary);
    font-weight: 500;
    white-space: nowrap;
    flex-shrink: 0;
    font-size: 0.85rem;
}

.explanation-item span {
    font-size: 0.82rem;
    color: var(--text-secondary);
    line-height: 1.5;
}

/* ---------- Test Area ---------- */
.test-area {
    display: flex;
    flex-direction: column;
    gap: 12px;
}

.test-input {
    width: 100%;
    padding: 14px 16px;
    background: var(--bg-surface);
    border: 1px solid var(--border);
    border-radius: var(--radius-md);
    color: var(--text-primary);
    font-family: var(--font-mono);
    font-size: 0.85rem;
    line-height: 1.6;
    resize: vertical;
    transition: border-color var(--transition-fast);
}

.test-input:focus {
    outline: none;
    border-color: var(--primary);
    box-shadow: 0 0 0 3px var(--primary-glow);
}

.test-input::placeholder {
    color: var(--text-tertiary);
    font-family: var(--font-body);
}

.match-count {
    font-size: 0.75rem;
    font-weight: 600;
    color: var(--text-tertiary);
    padding: 3px 10px;
    background: var(--bg-surface);
    border-radius: var(--radius-xl);
}

.test-results {
    display: flex;
    flex-direction: column;
    gap: 4px;
}

.test-line {
    padding: 8px 12px;
    background: var(--bg-surface);
    border-radius: var(--radius-sm);
    font-family: var(--font-mono);
    font-size: 0.82rem;
    line-height: 1.5;
    display: flex;
    align-items: center;
    gap: 10px;
}

.test-line .status {
    flex-shrink: 0;
    font-size: 0.7rem;
}

.test-line.match .status {
    color: var(--success);
}

.test-line.no-match .status {
    color: var(--accent);
}

.test-line .text {
    flex: 1;
    word-break: break-all;
}

.test-line .text mark {
    background: rgba(245, 158, 11, 0.25);
    color: var(--primary);
    padding: 1px 2px;
    border-radius: 2px;
}

/* ---------- Modals ---------- */
.modal-overlay {
    position: fixed;
    inset: 0;
    background: rgba(0, 0, 0, 0.7);
    backdrop-filter: blur(6px);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 1000;
    animation: fadeIn var(--transition-base);
}

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

.modal {
    width: 90%;
    max-width: 550px;
    max-height: 80vh;
    border-radius: var(--radius-lg);
    overflow: hidden;
    animation: slideUp var(--transition-smooth);
    display: flex;
    flex-direction: column;
}

.modal-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 16px 20px;
    border-bottom: 1px solid var(--border);
}

.modal-header h2 {
    font-size: 1rem;
    font-weight: 600;
}

.modal-close {
    width: 32px;
    height: 32px;
    display: flex;
    align-items: center;
    justify-content: center;
    border: none;
    background: transparent;
    color: var(--text-tertiary);
    font-size: 1.4rem;
    cursor: pointer;
    border-radius: var(--radius-sm);
    transition: all var(--transition-fast);
}

.modal-close:hover {
    background: var(--bg-elevated);
    color: var(--text-primary);
}

.saved-list {
    padding: 16px;
    overflow-y: auto;
    display: flex;
    flex-direction: column;
    gap: 8px;
}

.saved-item {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 12px 14px;
    background: var(--bg-surface);
    border-radius: var(--radius-md);
    cursor: pointer;
    transition: all var(--transition-fast);
}

.saved-item:hover {
    background: var(--bg-elevated);
    transform: translateX(4px);
}

.saved-item-info {
    flex: 1;
    min-width: 0;
}

.saved-item-info h4 {
    font-size: 0.82rem;
    font-weight: 600;
    margin-bottom: 2px;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

.saved-item-info code {
    font-family: var(--font-mono);
    font-size: 0.72rem;
    color: var(--primary);
}

.saved-item .delete-btn {
    width: 24px;
    height: 24px;
    border: none;
    background: transparent;
    color: var(--text-tertiary);
    cursor: pointer;
    border-radius: var(--radius-sm);
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all var(--transition-fast);
    flex-shrink: 0;
}

.saved-item .delete-btn:hover {
    color: var(--accent);
    background: var(--accent-glow);
}

.saved-empty {
    text-align: center;
    padding: 32px 16px;
    color: var(--text-tertiary);
    font-size: 0.85rem;
}

/* ---------- Toast ---------- */
.toast-container {
    position: fixed;
    bottom: 20px;
    right: 20px;
    display: flex;
    flex-direction: column;
    gap: 8px;
    z-index: 2000;
}

.toast {
    padding: 10px 16px;
    background: var(--bg-surface);
    border: 1px solid var(--border);
    border-radius: var(--radius-md);
    box-shadow: var(--shadow-md);
    font-size: 0.8rem;
    color: var(--text-primary);
    display: flex;
    align-items: center;
    gap: 8px;
    animation: slideInRight var(--transition-smooth);
    backdrop-filter: blur(12px);
    max-width: 320px;
}

.toast.success {
    border-left: 3px solid var(--success);
}

.toast.error {
    border-left: 3px solid var(--accent);
}

.toast.info {
    border-left: 3px solid var(--info);
}

.toast.fade-out {
    animation: fadeOut var(--transition-base) forwards;
}

/* ---------- Animations ---------- */
@keyframes fadeIn {
    from {
        opacity: 0;
    }

    to {
        opacity: 1;
    }
}

@keyframes slideUp {
    from {
        opacity: 0;
        transform: translateY(16px);
    }

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

@keyframes slideInRight {
    from {
        opacity: 0;
        transform: translateX(60px);
    }

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

@keyframes fadeOut {
    from {
        opacity: 1;
        transform: translateX(0);
    }

    to {
        opacity: 0;
        transform: translateX(60px);
    }
}

/* ---------- Responsive ---------- */
@media (max-width: 640px) {
    html {
        font-size: 14px;
    }

    .input-wrapper {
        flex-direction: column;
        align-items: stretch;
    }

    .generate-btn {
        justify-content: center;
    }

    .regex-display {
        flex-direction: column;
        align-items: flex-start;
    }

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

    .header-content {
        padding: 12px 16px;
    }

    .main {
        padding: 20px 16px 40px;
    }
}

/* ---------- Focus ---------- */
:focus-visible {
    outline: 2px solid var(--primary);
    outline-offset: 2px;
}

button:focus:not(:focus-visible) {
    outline: none;
}

/* ---------- Scrollbar ---------- */
::-webkit-scrollbar {
    width: 6px;
    height: 6px;
}

::-webkit-scrollbar-track {
    background: transparent;
}

::-webkit-scrollbar-thumb {
    background: rgba(255, 255, 255, 0.08);
    border-radius: 3px;
}

::-webkit-scrollbar-thumb:hover {
    background: rgba(255, 255, 255, 0.15);
}