/* Reset and Base Styles */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Poppins', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
}

/* Light Mode (Pastel Yellow & White) */
:root {
    --primary-color: #f59e0b;
    --primary-hover: #d97706;
    --secondary-color: #fbbf24;
    --background: #fef9e7;
    --card-background: #ffffff;
    --text-primary: #fbbf24;
    --text-secondary: #d97706;
    --border-color: #fde68a;
    --shadow: 0 1px 3px 0 rgb(120 53 15 / 0.1), 0 1px 2px -1px rgb(120 53 15 / 0.1);
    --shadow-lg: 0 10px 15px -3px rgb(120 53 15 / 0.15), 0 4px 6px -4px rgb(120 53 15 / 0.1);
}

/* Dark Mode (Dark Grey & Purple) */
[data-theme="dark"] {
    --primary-color: #a78bfa;
    --primary-hover: #8b5cf6;
    --secondary-color: #c084fc;
    --background: #1f2937;
    --card-background: #374151;
    --text-primary: #f3f4f6;
    --text-secondary: #d1d5db;
    --border-color: #4b5563;
    --shadow: 0 1px 3px 0 rgb(0 0 0 / 0.3), 0 1px 2px -1px rgb(0 0 0 / 0.3);
    --shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 0.4), 0 4px 6px -4px rgb(0 0 0 / 0.3);
}

[data-theme="dark"] #textInput {
    color: #e5e7eb;
}

body {
    font-family: 'Poppins', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
    background: var(--background);
    color: var(--text-primary);
    line-height: 1.6;
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: background-color 0.3s ease, color 0.3s ease;
}

/* Container */
.container {
    max-width: 700px;
    margin: 0 auto;
    padding: 2rem;
    width: 100%;
}

/* Header */
header {
    text-align: center;
    margin-bottom: 3rem;
    position: relative;
}

header h1 {
    font-size: 2.5rem;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: 0.5rem;
}

/* Theme Toggle Button - Lamp Style */
.theme-toggle {
    position: absolute;
    top: 5px;
    right: calc(-10% + 60px);
    background: var(--card-background);
    border: 2px solid var(--border-color);
    color: var(--text-primary);
    width: 50px;
    height: 50px;
    border-radius: 50%;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.5rem;
    transition: all 0.3s ease;
    box-shadow: var(--shadow);
}

/* Settings Toggle Button */
.settings-toggle {
    position: absolute;
    top: 5px;
    right: -10%;
    background: var(--card-background);
    border: 2px solid var(--border-color);
    color: var(--text-primary);
    width: 50px;
    height: 50px;
    border-radius: 50%;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.5rem;
    transition: all 0.3s ease;
    box-shadow: var(--shadow);
}

.settings-toggle:hover {
    transform: scale(1.1) rotate(90deg);
    box-shadow: var(--shadow-lg);
}

.settings-toggle:active {
    transform: scale(0.9) rotate(0deg);
}

.theme-toggle.lamp-on {
    background: linear-gradient(135deg, #fef3c7 0%, #fde68a 100%);
    border-color: #fbbf24;
    filter: brightness(1.1);
    box-shadow: 0 0 20px rgba(251, 191, 36, 0.4), var(--shadow);
}

.theme-toggle.lamp-off {
    background: var(--card-background);
    border-color: var(--border-color);
    filter: brightness(0.7) grayscale(0.3);
}

.theme-toggle:hover {
    transform: scale(1.1) rotate(-5deg);
    box-shadow: var(--shadow-lg);
}

.theme-toggle.lamp-on:hover {
    box-shadow: 0 0 30px rgba(251, 191, 36, 0.6), var(--shadow-lg);
    filter: brightness(1.2);
}

.theme-toggle:active {
    transform: scale(0.9) rotate(0deg);
}

/* Add a subtle pulse animation for the lamp when on */
@keyframes lamp-glow {
    0%, 100% {
        filter: brightness(1.1);
    }
    50% {
        filter: brightness(1.15);
    }
}

.theme-toggle.lamp-on {
    animation: lamp-glow 2s ease-in-out infinite;
}

.subtitle {
    color: var(--text-secondary);
    font-size: 1.1rem;
}

/* Main Content */
main {
    display: flex;
    flex-direction: column;
    gap: 2rem;
}

/* Input Section */
.input-section {
    width: 120%;
    margin-left: -10%;
    margin-right: -10%;
}

#textInput {
    width: 100%;
    padding: 1rem;
    font-size: 1rem;
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, monospace;
    border: 2px solid var(--border-color);
    border-radius: 0.5rem;
    background: var(--card-background);
    color: var(--text-secondary);
    resize: none;
    overflow-y: auto;
    transition: border-color 0.2s, background-color 0.3s ease, color 0.3s ease;
    box-shadow: var(--shadow);
}

#textInput:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: var(--shadow-lg);
}

#textInput::placeholder {
    color: var(--text-secondary);
    opacity: 0.6;
}

/* Stats Section */
.stats-section {
    display: flex;
    justify-content: center;
    gap: 2rem;
    flex-wrap: wrap;
}

.stat-card {
    background: var(--card-background);
    padding: 2rem 3rem;
    border-radius: 0.75rem;
    text-align: center;
    border: 1px solid var(--border-color);
    box-shadow: var(--shadow);
    transition: transform 0.2s, box-shadow 0.2s, background-color 0.3s ease, border-color 0.3s ease;
    min-width: 200px;
}

.stat-card:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
}

.stat-value {
    font-size: 2.5rem;
    font-weight: 700;
    color: var(--primary-color);
    margin-bottom: 0.5rem;
}

.stat-label {
    font-size: 0.875rem;
    color: var(--text-secondary);
    font-weight: 500;
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

/* Action Section */
.action-section {
    display: flex;
    gap: 1rem;
    justify-content: center;
    flex-wrap: wrap;
}

.btn {
    padding: 0.75rem 1.5rem;
    font-size: 1rem;
    font-weight: 600;
    border: none;
    border-radius: 0.5rem;
    cursor: pointer;
    transition: all 0.2s;
    box-shadow: var(--shadow);
    min-width: 140px;
}

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

.btn-primary:hover {
    background: var(--primary-hover);
    box-shadow: var(--shadow-lg);
}

.btn-secondary {
    background: var(--card-background);
    color: var(--text-primary);
    border: 2px solid var(--border-color);
}

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

.btn:active {
    transform: translateY(1px);
}

/* Success animation for buttons */
@keyframes success-pop {
    0% {
        transform: scale(1);
    }
    50% {
        transform: scale(1.1);
    }
    100% {
        transform: scale(1);
    }
}

@keyframes success-glow {
    0%, 100% {
        box-shadow: var(--shadow);
    }
    50% {
        box-shadow: 0 0 20px rgba(34, 197, 94, 0.5), var(--shadow-lg);
    }
}

.btn.success {
    animation: success-pop 0.3s ease, success-glow 0.6s ease;
    background: #22c55e !important;
    color: white !important;
}

/* Clear animation for buttons */
@keyframes sweep {
    0% {
        transform: translateX(-100%) rotate(-10deg);
        opacity: 0;
    }
    50% {
        opacity: 1;
    }
    100% {
        transform: translateX(100%) rotate(10deg);
        opacity: 0;
    }
}

.btn.cleared {
    animation: success-pop 0.3s ease;
    background: #3b82f6 !important;
    color: white !important;
}

/* Warning animation for buttons (e.g., input empty) */
@keyframes warning-shake {
    0%, 100% { transform: translateX(0); }
    20% { transform: translateX(-4px); }
    40% { transform: translateX(4px); }
    60% { transform: translateX(-3px); }
    80% { transform: translateX(3px); }
}

@keyframes warning-glow {
    0%, 100% { box-shadow: var(--shadow); }
    50% { box-shadow: 0 0 20px rgba(234, 179, 8, 0.5), var(--shadow-lg); }
}

.btn.warning {
    animation: warning-shake 0.4s ease, warning-glow 0.6s ease;
    background: #eab308 !important; /* amber-500 */
    color: #ffffff !important; /* near-black for contrast */
}

/* Footer */
footer {
    text-align: center;
    margin-top: 3rem;
    padding-top: 2rem;
    color: var(--text-secondary);
    font-size: 0.875rem;
}

.footer-text {
    display: inline-flex;
    align-items: center;
    gap: 0.25rem;
}

.tooltip-wrapper {
    position: relative;
    display: inline-flex;
    cursor: pointer;
    padding: 0.25rem 0.5rem;
    margin: -0.25rem -0.5rem;
}

.trademark {
    font-size: 0.75rem;
    vertical-align: super;
}

.tooltip {
    position: absolute;
    bottom: 100%;
    left: 50%;
    transform: translateX(-50%) translateY(-8px);
    background: var(--card-background);
    color: var(--text-primary);
    padding: 0.5rem 0.75rem;
    padding-bottom: 0.75rem;
    border-radius: 0.375rem;
    font-size: 0.875rem;
    white-space: nowrap;
    opacity: 0;
    pointer-events: none;
    transition: opacity 0.3s ease, transform 0.3s ease;
    box-shadow: var(--shadow-lg);
    border: 1px solid var(--border-color);
    z-index: 10;
}

.tooltip::after {
    content: '';
    position: absolute;
    top: 100%;
    left: 50%;
    transform: translateX(-50%);
    border: 6px solid transparent;
    border-top-color: var(--card-background);
}

.tooltip::before {
    content: '';
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    height: 10px;
}

.tooltip-wrapper:hover .tooltip {
    opacity: 1;
    transform: translateX(-50%) translateY(-12px);
    pointer-events: auto;
    transition-delay: 0.3s, 0.3s;
}

.tooltip:hover {
    opacity: 1;
    pointer-events: auto;
    transition-delay: 0s, 0s;
}

.tooltip a {
    color: var(--primary-color);
    text-decoration: none;
    font-weight: 600;
}

.tooltip a:hover {
    text-decoration: underline;
}

/* Settings Panel */
.settings-panel {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0, 0, 0, 0.5);
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    z-index: 1000;
    opacity: 0;
    pointer-events: none;
    transition: opacity 0.3s ease;
    padding: 1rem;
}

.settings-panel.show {
    opacity: 1;
    pointer-events: auto;
}

.settings-panel.hidden {
    display: none;
}

.settings-panel .settings-header,
.settings-panel .settings-content {
    background: var(--card-background);
    max-width: 500px;
    width: 90%;
    box-shadow: var(--shadow-lg);
    transform: scale(0.9);
    transition: transform 0.3s ease;
}

.settings-panel.show .settings-header,
.settings-panel.show .settings-content {
    transform: scale(1);
}

.settings-panel .settings-header {
    border-radius: 1rem 1rem 0 0;
}

.settings-panel .settings-content {
    border-radius: 0 0 1rem 1rem;
    max-height: calc(80vh - 100px);
    overflow-y: auto;
}

.settings-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1.5rem;
    border-bottom: 2px solid var(--border-color);
}

.settings-header h2 {
    color: var(--text-primary);
    font-size: 1.5rem;
    font-weight: 600;
    margin: 0;
}

.close-btn {
    background: transparent;
    border: none;
    color: var(--text-secondary);
    font-size: 1.5rem;
    cursor: pointer;
    width: 40px;
    height: 40px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 50%;
    transition: all 0.2s;
}

.close-btn:hover {
    background: var(--background);
    color: var(--text-primary);
    transform: rotate(90deg);
}

.settings-content {
    padding: 1.5rem;
}

.setting-group {
    margin-bottom: 1.5rem;
}

.setting-group:last-child {
    margin-bottom: 0;
}

.setting-group h3 {
    color: var(--text-primary);
    font-size: 1.125rem;
    font-weight: 600;
    margin-bottom: 0.5rem;
}

.setting-description {
    color: var(--text-secondary);
    font-size: 0.875rem;
    margin-bottom: 1rem;
}

.setting-item {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 1rem;
    margin-bottom: 1rem;
    padding: 0.75rem;
    background: var(--background);
    border-radius: 0.5rem;
    border: 1px solid var(--border-color);
}

.setting-item:last-child {
    margin-bottom: 0;
}

.setting-item label {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    color: var(--text-primary);
    font-weight: 500;
    cursor: pointer;
    flex: 1;
}

.setting-item input[type="checkbox"] {
    width: 26px;
    height: 26px;
    cursor: pointer;
    appearance: none;
    -webkit-appearance: none;
    -moz-appearance: none;
    border: 2px solid var(--border-color);
    border-radius: 0.5rem;
    background: var(--background);
    box-shadow: var(--shadow);
    position: relative;
    transition: background 0.2s ease, border-color 0.2s ease, box-shadow 0.2s ease, transform 0.1s ease;
}

.setting-item input[type="checkbox"]:hover {
    border-color: var(--primary-color);
    box-shadow: var(--shadow-lg);
}

.setting-item input[type="checkbox"]:active {
    transform: translateY(1px);
}

.setting-item input[type="checkbox"]:focus-visible {
    outline: none;
    box-shadow: 0 0 0 3px rgba(251, 191, 36, 0.25), var(--shadow-lg);
    border-color: var(--primary-color);
}

.setting-item input[type="checkbox"]::after {
    content: '✓';
    position: absolute;
    left: 50%;
    top: 50%;
    transform: translate(-50%, -50%) scale(0.6);
    color: transparent;
    font-weight: 800;
    font-size: 1rem;
    line-height: 1;
    transition: color 0.15s ease;
}

.setting-item input[type="checkbox"]:checked {
    background: linear-gradient(135deg, var(--secondary-color) 0%, var(--primary-color) 100%);
    border-color: var(--primary-color);
}

.setting-item input[type="checkbox"]:checked::after {
    color: #1f2937; /* dark tick for contrast on warm bg */
}

[data-theme="dark"] .setting-item input[type="checkbox"] {
    background: var(--card-background);
    border-color: var(--border-color);
}

[data-theme="dark"] .setting-item input[type="checkbox"]:checked::after {
    color: #111827;
}

.setting-item input[type="number"] {
    width: 120px;
    padding: 0.5rem 2.25rem 0.5rem 0.75rem; /* leave space for steppers */
    font-size: 0.875rem;
    border: 2px solid var(--border-color);
    border-radius: 0.375rem;
    background: var(--card-background);
    color: var(--text-primary);
    transition: border-color 0.2s;
    appearance: textfield; /* hide spinners in most browsers */
}

/* Hide native spinners - WebKit */
.setting-item input[type="number"]::-webkit-outer-spin-button,
.setting-item input[type="number"]::-webkit-inner-spin-button {
    -webkit-appearance: none;
    margin: 0;
}

/* Hide native spinners - Firefox */
.setting-item input[type="number"] {
    -moz-appearance: textfield;
}

.setting-item input[type="number"]:focus {
    outline: none;
    border-color: var(--primary-color);
}

.setting-item input[type="number"]:disabled {
    opacity: 0.5;
    cursor: not-allowed;
}

/* Custom number input steppers */
.number-input {
    position: relative;
    display: inline-flex;
    align-items: center;
}

.number-input .stepper-group {
    position: absolute;
    right: 4px;
    top: 50%;
    transform: translateY(-50%);
    display: flex;
    flex-direction: column;
    gap: 2px;
}

.number-input .stepper-btn {
    width: 26px;
    height: 18px;
    display: flex;
    align-items: center;
    justify-content: center;
    border: 1px solid var(--border-color);
    background: var(--background);
    color: var(--text-primary);
    border-radius: 4px;
    cursor: pointer;
    font-size: 0.65rem;
    line-height: 1;
    transition: background 0.2s, transform 0.1s, box-shadow 0.2s, border-color 0.2s;
    box-shadow: var(--shadow);
}

.number-input .stepper-btn:hover {
    background: var(--card-background);
    border-color: var(--primary-color);
    box-shadow: var(--shadow-lg);
}

.number-input .stepper-btn:active {
    transform: translateY(1px);
}

[data-theme="dark"] .number-input .stepper-btn {
    background: var(--card-background);
}

/* Red Zone Warnings */
.red-zone {
    animation: red-zone-pulse 1.5s ease-in-out infinite;
}

@keyframes red-zone-pulse {
    0%, 100% {
        border-color: #ef4444;
    }
    50% {
        border-color: #dc2626;
    }
}

.stat-card.red-zone {
    border-color: #ef4444;
    background: linear-gradient(135deg, rgba(239, 68, 68, 0.1) 0%, rgba(220, 38, 38, 0.05) 100%);
}

.stat-value.red-zone {
    color: #ef4444 !important;
    font-weight: 800;
}

#textInput.red-zone {
    border-color: #ef4444;
    box-shadow: 0 0 0 3px rgba(239, 68, 68, 0.1), var(--shadow);
}

#textInput.red-zone:focus {
    border-color: #dc2626;
    box-shadow: 0 0 0 3px rgba(239, 68, 68, 0.2), var(--shadow-lg);
}

/* Responsive Design */
@media (max-width: 768px) {
    body {
        align-items: flex-start;
        padding: 2rem 0;
    }

    .container {
        padding: 1rem;
    }

    header {
        padding-top: 3rem;
    }

    header h1 {
        font-size: 2rem;
    }

    .subtitle {
        font-size: 1rem;
    }

    .input-section {
        width: 100%;
        margin-left: 0;
        margin-right: 0;
    }

    /* Center header controls as a symmetric pair */
    header {
        --control-size: 45px;
        --control-gap: 12px;
        --controls-offset: calc((var(--control-gap) + var(--control-size)) / 2);
    }

    .theme-toggle {
        width: 45px;
        height: 45px;
        font-size: 1.3rem;
        top: -0.5rem;
        left: calc(45% - var(--controls-offset));
        right: auto;
        transform: none;
    }
    
    .theme-toggle:hover {
        transform: scale(1.1) rotate(-5deg);
    }
    
    .theme-toggle:active {
        transform: scale(0.9) rotate(0deg);
    }
    .settings-toggle {
        width: 45px;
        height: 45px;
        font-size: 1.3rem;
        top: -0.5rem;
        left: calc(50% + var(--controls-offset));
        right: auto;
        transform: none;
    }

    .settings-toggle:hover {
        transform: scale(1.1) rotate(90deg);
    }

    .settings-toggle:active {
        transform: scale(0.9) rotate(0deg);
    }
    
    .theme-toggle.lamp-on {
        box-shadow: 0 0 15px rgba(251, 191, 36, 0.4), var(--shadow);
    }
    
    .theme-toggle.lamp-on:hover {
        box-shadow: 0 0 25px rgba(251, 191, 36, 0.6), var(--shadow-lg);
    }

    .stats-section {
        gap: 1.5rem;
    }

    .stat-card {
        padding: 1.5rem 2.5rem;
        min-width: 180px;
    }

    .stat-value {
        font-size: 1.75rem;
    }
}

@media (max-width: 480px) {
    .stats-section {
        flex-direction: column;
        width: 100%;
    }

    .stat-card {
        width: 100%;
        min-width: unset;
    }

    .action-section {
        flex-direction: column;
    }

    .btn {
        width: 100%;
    }
}