:root {
    --bg-color: #0f172a;
    --card-bg: #1e293b;
    --text-primary: #f1f5f9;
    /* Slightly brighter white */
    --text-secondary: #94a3b8;
    --accent-color: #3b82f6;
    --accent-hover: #2563eb;
    --error-color: #ef4444;
    --success-color: #22c55e;
    --border-color: #334155;
    --input-bg: #020617;
    --ring-color: rgba(59, 130, 246, 0.5);
}

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

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
    background-color: var(--bg-color);
    color: var(--text-primary);
    line-height: 1.6;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    align-items: center;
    padding: 2rem 1rem;
    -webkit-font-smoothing: antialiased;
    /* Smoother fonts */
}

.container {
    width: 100%;
    max-width: 800px;
    background-color: var(--card-bg);
    border-radius: 1rem;
    box-shadow: 0 20px 25px -5px rgba(0, 0, 0, 0.3), 0 10px 10px -5px rgba(0, 0, 0, 0.2);
    /* Deeper shadow */
    padding: 2.5rem;
    /* More padding */
    border: 1px solid var(--border-color);
}

/* Navigation */
.top-nav {
    display: grid;
    grid-template-columns: 1fr auto 1fr;
    align-items: center;
    padding-bottom: 1.5rem;
    margin-bottom: 2rem;
    border-bottom: 1px solid var(--border-color);
}

.site-name {
    font-size: 1.25rem;
    font-weight: 700;
    color: var(--text-primary);
    letter-spacing: -0.025em;
}

.nav-tabs {
    display: flex;
    gap: 0.25rem;
    background-color: var(--input-bg);
    padding: 0.25rem;
    border-radius: 0.5rem;
    border: 1px solid var(--border-color);
}

.nav-tab {
    background: transparent;
    border: none;
    color: var(--text-secondary);
    padding: 0.4rem 1rem;
    font-size: 0.9rem;
    font-weight: 500;
    cursor: pointer;
    border-radius: 0.375rem;
    transition: all 0.2s;
}

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

.nav-tab.active {
    background-color: var(--accent-color);
    color: white;
}

header {
    text-align: center;
    margin-bottom: 2rem;
    /* Removed border-bottom from here as it's now on nav or not needed */
    padding-bottom: 0;
}

h1 {
    font-size: 2rem;
    /* Larger title */
    font-weight: 800;
    /* Bolder */
    background: linear-gradient(to right, #60a5fa, #a78bfa);
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
    margin-bottom: 0.75rem;
    letter-spacing: -0.025em;
    /* Modern tight spacing */
}

.subtitle {
    color: var(--text-secondary);
    font-size: 1rem;
    /* Slightly larger */
    max-width: 600px;
    margin: 0 auto;
}

.section {
    margin-bottom: 2rem;
    /* More breathing room */
}

label {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: 600;
    color: var(--text-secondary);
    font-size: 0.9rem;
}

textarea,
input[type="password"],
input[type="number"],
input[type="text"] {
    width: 100%;
    padding: 0.875rem;
    /* More comfortable padding */
    background-color: var(--input-bg);
    border: 1px solid var(--border-color);
    border-radius: 0.5rem;
    color: var(--text-primary);
    font-family: monospace;
    font-size: 0.95rem;
    transition: border-color 0.2s, box-shadow 0.2s, background-color 0.2s;
}

textarea:focus,
input[type="password"]:focus,
input[type="number"]:focus,
input[type="text"]:focus {
    outline: none;
    border-color: var(--accent-color);
    box-shadow: 0 0 0 4px var(--ring-color);
    /* Nice focus ring */
    background-color: rgba(2, 6, 23, 0.8);
}

textarea {
    min-height: 120px;
    resize: vertical;
}

.controls {
    display: flex;
    gap: 1rem;
    margin-bottom: 1.5rem;
    flex-wrap: wrap;
}

.input-row {
    display: flex;
    gap: 1rem;
    margin-bottom: 0.5rem;
    align-items: flex-start;
}

.input-group {
    flex: 1;
    text-align: center;
}

.input-row+.help-text {
    margin-top: 0;
    margin-bottom: 1.5rem;
}

button {
    flex: 1;
    padding: 0.75rem 1.5rem;
    border: none;
    border-radius: 0.5rem;
    font-weight: 600;
    cursor: pointer;
    transition: transform 0.1s, opacity 0.2s, background-color 0.2s;
    font-size: 1rem;
    min-width: 120px;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
}

button:active {
    transform: scale(0.98);
    /* Satisfying click effect */
}

button:disabled {
    opacity: 0.5;
    cursor: not-allowed;
}

.btn-encrypt {
    background-color: var(--card-bg);
    border: 1px solid var(--accent-color);
    color: var(--accent-color);
}

.btn-encrypt:hover:not(:disabled) {
    background-color: var(--accent-hover);
}

.btn-decrypt {
    background-color: var(--card-bg);
    border: 1px solid var(--accent-color);
    color: var(--accent-color);
}

.btn-decrypt:hover:not(:disabled) {
    background-color: rgba(59, 130, 246, 0.1);
}

.btn-copy {
    background-color: var(--border-color);
    color: var(--text-secondary);
    font-size: 0.85rem;
    padding: 0.5rem 1rem;
    margin-top: 0.5rem;
    width: auto;
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
}

.btn-copy:hover {
    background-color: #475569;
    color: white;
}

.output-container {
    position: relative;
}

.qr-status {
    margin-top: 0.5rem;
    font-size: 0.85rem;
    color: var(--text-secondary);
    padding: 0.5rem;
    border-radius: 0.25rem;
    background-color: rgba(255, 255, 255, 0.05);
    border: 1px solid var(--border-color);
}

.qr-file-row {
    display: flex;
    align-items: center;
    gap: 1rem;
    margin-bottom: 0.5rem;
}

.qr-file-name {
    font-size: 0.9rem;
    color: var(--text-secondary);
    word-break: break-all;
}

#qr-input-file {
    display: none;
}

.status-message {
    margin-top: 0.5rem;
    font-size: 0.9rem;
    min-height: 1.5rem;
    text-align: center;
}

.error {
    color: var(--error-color);
}

.success {
    color: var(--success-color);
}

.info-section {
    margin-top: 4rem;
    padding-top: 3rem;
    border-top: 1px solid var(--border-color);
    color: var(--text-secondary);
    font-size: 0.95rem;
}

.info-section h2 {
    color: var(--text-primary);
    font-size: 1.5rem;
    margin-bottom: 1.5rem;
    margin-top: 2rem;
    font-weight: 700;
    letter-spacing: -0.025em;
}

.info-section ul {
    padding-left: 1.5rem;
    margin-bottom: 1.5rem;
    line-height: 1.7;
}

.info-section li {
    margin-bottom: 0.75rem;
}

.disclaimer {
    background-color: rgba(245, 158, 11, 0.1);
    /* Amber tint */
    border: 1px solid rgba(245, 158, 11, 0.2);
    padding: 1.5rem;
    border-radius: 0.75rem;
    margin-top: 3rem;
}

.disclaimer h3 {
    color: #fbbf24;
    /* Amber-400 */
    margin-bottom: 0.5rem;
    font-size: 1.1rem;
}

.disclaimer p {
    font-size: 0.9rem;
    color: #cbd5e1;
}

.disclaimer strong {
    color: #fbbf24;
}

/* Advanced Options Toggle */
.advanced-toggle {
    background-color: rgba(255, 255, 255, 0.05);
    border: 1px solid var(--border-color);
    color: var(--text-secondary);
    font-size: 0.85rem;
    cursor: pointer;
    padding: 0.4rem 0.8rem;
    border-radius: 0.5rem;
    margin-bottom: 1rem;
    display: inline-flex;
    width: auto;
    text-align: center;
    text-decoration: none;
    transition: background-color 0.2s, color 0.2s;
}

.advanced-toggle:hover {
    background-color: rgba(255, 255, 255, 0.1);
    color: var(--text-primary);
}

.advanced-options {
    display: none;
    padding: 1rem;
    background-color: var(--input-bg);
    border: 1px solid var(--border-color);
    border-radius: 0.5rem;
    margin-bottom: 1.5rem;
}

.advanced-options.show {
    display: block;
}

.advanced-group {
    display: flex;
    gap: 1rem;
    align-items: center;
}

.advanced-group input {
    width: 120px;
    padding: 0.5rem;
}

@media (max-width: 600px) {
    .container {
        padding: 1.5rem;
    }

    .controls {
        flex-direction: column;
    }

    button {
        width: 100%;
    }
}

/* QR Mode Styles */
#qrMode {
    display: none;
}

.back-btn {
    background: none;
    border: none;
    color: var(--accent-color);
    cursor: pointer;
    font-size: 0.9rem;
    margin-bottom: 1rem;
    padding: 0;
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
}

.back-btn:hover {
    text-decoration: underline;
}

/* Refined UI Layout */
.top-actions {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 0.5rem;
    /* Left/Right alignment for clear and QR buttons */
    gap: 0.75rem;
}


.qr-entry-button {
    width: auto;
    /* Allow proportional shrinking */
    flex: 0 1 auto;
    min-width: 0;
    justify-content: center;
    padding: 0.4rem 0.8rem;
    font-size: 0.85rem;
    background-color: var(--card-bg);
    border: 1px dashed var(--accent-color);
    color: var(--accent-color);
    border-radius: 0.5rem;
    cursor: pointer;
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    transition: background-color 0.2s;
    /* Allow text wrapping */
    white-space: normal;
    height: auto;
    text-align: center;
    line-height: 1.2;
}

.qr-entry-button:hover {
    background-color: rgba(59, 130, 246, 0.1);
}

.qr-entry-button:active {
    transform: scale(0.98);
}

.output-actions {
    display: flex;
    justify-content: flex-end;
    gap: 0.5rem;
    width: 100%;
}

.output-action-button {
    width: auto;
    min-width: 140px;
    padding: 0.5rem 1rem;
    font-size: 0.85rem;
    background-color: var(--border-color);
    color: var(--text-secondary);
    border: none;
    border-radius: 0.5rem;
    cursor: pointer;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
    transition: background-color 0.2s, color 0.2s;
}

.output-action-button:hover {
    background-color: #475569;
    color: white;
}

.output-action-button:active {
    transform: scale(0.98);
}

/* Specific layout adjustments */
.output-actions .primary-copy,
.output-actions .secondary-qrcode,
.output-actions .secondary-link {
    flex: 1;
    min-width: 0; /* Ensure all buttons can shrink equally */
}

/* QR Select Section Redesign */
.qr-select-card {
    background-color: transparent;
    border: none;
    /* Removed border-radius as it's not needed without background/border */
    padding: 2rem 0;
    /* Adjusted padding to be vertical only if needed, or keep it */
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 1rem;
    text-align: center;
}

.qr-choose-button {
    background-color: var(--accent-color);
    color: white;
    border: none;
    border-radius: 0.5rem;
    padding: 0.75rem 1.5rem;
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    transition: background-color 0.2s, transform 0.1s;
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
}

.qr-choose-button:hover {
    background-color: #2563eb;
    transform: translateY(-1px);
}

.qr-choose-button:active {
    transform: scale(0.98);
}

.qr-file-info-container {
    display: flex;
    justify-content: center;
    width: 100%;
}

.qr-file-name-pill {
    background-color: rgba(255, 255, 255, 0.05);
    border: 1px solid var(--border-color);
    border-radius: 9999px;
    padding: 0.25rem 1rem;
    font-size: 0.85rem;
    color: var(--text-primary);
    max-width: 80%;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

.qr-status-text {
    font-size: 0.85rem;
    color: var(--text-secondary);
    margin-top: 0.5rem;
    line-height: 1.4;
}

.help-text {
    margin-top: 0.35rem;
    color: var(--text-secondary);
    font-size: 0.8rem;
    line-height: 1.4;
}

#btn-download-qr {
    margin: 1rem auto 0 auto;
    min-width: 180px;
    display: none;
}

.input-error {
    border-color: var(--error-color) !important;
    box-shadow: 0 0 0 4px rgba(239, 68, 68, 0.35) !important;
}

#qr-section {
    margin-top: 1.5rem;
    display: none;
    text-align: center;
    border: 1px dashed var(--border-color);
    border-radius: 0.5rem;
    padding: 1.5rem;
    background-color: rgba(255, 255, 255, 0.02);
}

#qr-code-container {
    background: white;
    padding: 1rem;
    display: inline-block;
    border-radius: 0.5rem;
    box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
}

.icon {
    width: 16px;
    height: 16px;
    fill: none;
    stroke: currentColor;
    display: inline-block;
}

.icon-20 {
    width: 20px;
    height: 20px;
}

.icon path {
    stroke-linecap: round;
    stroke-linejoin: round;
    stroke-width: 2;
}

#unsupported-warning {
    display: none;
    background-color: #ef4444;
    color: white;
    padding: 1rem;
    border-radius: 0.5rem;
    margin-bottom: 1.5rem;
    text-align: center;
}

.label-compact {
    margin-bottom: 0;
}

.advanced-help {
    font-size: 0.8rem;
    color: var(--text-secondary);
    margin-top: 0.5rem;
}

.column-stack {
    display: flex;
    flex-direction: column;
    margin-top: 0.5rem;
    gap: 0.5rem;
}

.qr-meta {
    margin-top: 0.75rem;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 0.35rem;
}

.qr-or {
    color: var(--text-secondary);
    font-size: 0.85rem;
}

.help-text-tight {
    margin: 0;
}

.qr-title {
    margin-bottom: 0.5rem;
    color: var(--text-primary);
}

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

.textarea-subtle {
    background-color: rgba(255, 255, 255, 0.03);
}

.btn-qr-decrypt {
    background-color: var(--accent-color);
    color: white;
    width: 100%;
}

.qr-footnote {
    font-size: 0.8rem;
    color: var(--text-secondary);
    text-align: center;
    margin-top: 2rem;
}

/* Password Toggle Styles */
.password-container {
    position: relative;
    display: flex;
    align-items: center;
    width: 100%;
}

.password-container input[type="password"],
.password-container input[type="text"] {
    padding-right: 40px; /* Make room for the eye icon */
}

.password-toggle {
    position: absolute;
    right: 10px;
    background: none;
    border: none;
    padding: 0;
    cursor: pointer;
    color: var(--text-secondary);
    display: flex;
    align-items: center;
    justify-content: center;
    min-width: auto; /* Override default button min-width */
    width: 24px;
    height: 24px;
    transition: color 0.2s;
}

.password-toggle:hover {
    color: var(--accent-color);
    background: none; /* Override default button hover background */
}

.password-toggle:active {
    transform: scale(0.95);
}

.password-toggle .icon {
    width: 20px;
    height: 20px;
}

/* URL Notice Styles */
.url-notice {
    margin-top: 0.5rem;
    padding: 0.75rem;
    background-color: rgba(59, 130, 246, 0.1);
    border: 1px solid rgba(59, 130, 246, 0.2);
    border-radius: 0.5rem;
    color: #60a5fa;
    font-size: 0.875rem;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.url-notice::before {
    content: "ℹ";
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 1.25rem;
    height: 1.25rem;
    background-color: rgba(59, 130, 246, 0.2);
    border-radius: 50%;
    font-size: 0.75rem;
    font-weight: bold;
}

/* Clear Button Styles */
.label-row {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 0.5rem;
}

.label-row label {
    margin-bottom: 0; /* Override default label margin */
}

.btn-clear {
    background: none;
    border: none;
    color: var(--text-secondary);
    font-size: 0.875rem;
    cursor: pointer;
    padding: 0.25rem 0.5rem;
    border-radius: 0.25rem;
    transition: all 0.2s;
}

.btn-clear:hover {
    color: var(--error-color);
    background-color: rgba(239, 68, 68, 0.1);
}

/* Clear Screen Button Styles */
.top-actions {
    display: flex;
    align-items: center;
    margin-bottom: 1rem;
    gap: 1rem;
    /* flex-wrap: wrap; Removed to prevent wrapping */
}

.btn-clear-screen {
    width:auto;
    flex: 0 1 auto;
    min-width: 0;
    justify-content: center;
    padding: 0.4rem 0.8rem;
    font-size: 0.85rem;
    background-color: transparent;
    border: 1px solid var(--border-color);
    color: var(--text-secondary);
    border-radius: 0.5rem;
    cursor: pointer;
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    transition: all 0.2s;
    /* Allow text wrapping */
    white-space: normal;
    height: auto;
    text-align: center;
    line-height: 1.2;
}

.btn-clear-screen:hover {
    background-color: rgba(239, 68, 68, 0.1);
    color: var(--error-color);
    border-color: var(--error-color);
}

.btn-clear-screen:active {
    transform: scale(0.98);
}

.btn-clear-screen .icon {
    width: 16px;
    height: 16px;
}





/* Center Labels */
/* Center Labels */
.section > label[for="encrypt-input"],
.section > label[for="decrypt-input"],
.section > label[for="encrypt-password"],
.section > label[for="decrypt-password"],
.output-container > label[for="encrypt-output"],
.output-container > label[for="decrypt-output"],
.section > label[for="qrCiphertext"],
.input-group > label[for="qrPassword"],
.input-group > label[for="qrIterationsInput"],
.output-container > label[for="qrPlaintextOutput"] {
    text-align: center;
    display: block;
    width: 100%;
}

/* FAQ and Security Sections */
.faq-section {
    margin-top: 4rem;
    padding-top: 3rem;
    border-top: 1px solid var(--border-color);
    color: var(--text-secondary);
    font-size: 0.95rem;
}

.security-section {
    margin-top: 4rem;
    background-color: rgba(245, 158, 11, 0.1); /* Amber tint */
    border: 1px solid rgba(245, 158, 11, 0.2);
    padding: 1.5rem;
    border-radius: 0.75rem;
}

.faq-section h2 {
    color: var(--text-primary);
    font-size: 1.5rem;
    margin-bottom: 1.5rem;
    font-weight: 700;
    letter-spacing: -0.025em;
}

.security-section h2 {
    color: #fbbf24; /* Amber-400 */
    font-size: 1.5rem;
    margin-bottom: 1.5rem;
    font-weight: 700;
    letter-spacing: -0.025em;
}

.security-section p {
    font-size: 0.9rem;
    color: #cbd5e1;
    margin-bottom: 1rem;
    line-height: 1.6;
}

.security-section strong {
    color: #fbbf24;
}

.faq-item {
    margin-bottom: 2.5rem;
}

.faq-item h3 {
    color: var(--text-primary);
    font-size: 1.1rem;
    margin-bottom: 0.5rem;
    font-weight: 600;
}

.faq-item p,
.faq-item ul,
.faq-item ol {
    margin-bottom: 1rem;
    line-height: 1.6;
}

.faq-item ul,
.faq-item ol {
    padding-left: 1.5rem;
}

.faq-item li {
    margin-bottom: 0.5rem;
}

.security-section p {
    margin-bottom: 1rem;
    line-height: 1.6;
}
/* Header Layout */
/* Header Layout */
.site-header {
    text-align: center;
    margin-bottom: 2rem;
}

/* Nav Brand */
.nav-brand {
    display: flex;
    align-items: center;
    gap: 0.75rem;
}

.site-logo-nav {
    display: inline-flex;
    align-items: center;
    text-decoration: none;
}

.site-logo-nav img {
    height: 32px;
    width: auto;
    transition: transform 0.2s ease;
}

.site-logo-nav:hover img {
    transform: scale(1.05);
}

/* Language Selector */
.nav-actions {
    display: flex;
    justify-content: flex-end;
}

.lang-selector {
    position: relative;
}

.lang-btn {
    background: transparent;
    border: 1px solid var(--border-color);
    color: var(--text-secondary);
    padding: 0.4rem 0.8rem;
    font-size: 0.9rem;
    border-radius: 0.5rem;
    display: flex;
    align-items: center;
    gap: 0.5rem;
    cursor: pointer;
    min-width: auto;
    transition: all 0.2s;
}

.lang-btn:hover {
    color: var(--text-primary);
    border-color: var(--text-secondary);
    background-color: rgba(255, 255, 255, 0.05);
}

.lang-dropdown {
    position: absolute;
    top: 100%;
    right: 0;
    margin-top: 0.5rem;
    background-color: var(--card-bg);
    border: 1px solid var(--border-color);
    border-radius: 0.5rem;
    padding: 0.35rem;
    min-width: 140px;
    display: none;
    flex-direction: column;
    gap: 0.25rem;
    box-shadow: 0 10px 15px -3px rgba(0, 0, 0, 0.3);
    z-index: 50;
}

.lang-dropdown::before {
    content: "";
    position: absolute;
    top: -0.5rem;
    left: 0;
    right: 0;
    height: 0.5rem;
}

.lang-selector:hover .lang-dropdown {
    display: flex;
}

.lang-item {
    display: block;
    padding: 0.5rem 0.75rem;
    color: var(--text-secondary);
    text-decoration: none;
    border-radius: 0.35rem;
    font-size: 0.9rem;
    transition: background-color 0.2s, color 0.2s;
    text-align: left;
}

.lang-item:hover {
    background-color: var(--input-bg);
    color: var(--text-primary);
}

.lang-item.active {
    color: var(--accent-color);
    font-weight: 600;
    background-color: rgba(59, 130, 246, 0.1);
}

.icon-sm {
    width: 14px;
    height: 14px;
    opacity: 0.7;
}

/* Responsive Header */
@media (max-width: 600px) {
    .top-nav {
        display: flex;
        flex-direction: column;
        gap: 1rem;
        align-items: center;
    }
    
    .nav-brand {
        width: 100%;
        justify-content: center;
    }

    .nav-actions {
        width: 100%;
        justify-content: center;
    }
}