/* SafeZone Preview — Styles */
/* ========================================
   DESIGN TOKENS
   ======================================== */
:root {
    /* Backgrounds */
    --bg-body: #0D0D0D;
    --bg-surface: #1A1A1A;
    --bg-card: #1E1E1E;
    --bg-card-hover: #252525;
    --bg-input: #141414;
    --border-subtle: #2A2A2A;
    --border-medium: #3A3A3A;

    /* Text */
    --text-primary: #FFFFFF;
    --text-secondary: #A0A0A0;
    --text-muted: #666666;
    --text-dim: #444444;

    /* Platform Colors */
    --tiktok-primary: #00F2EA;
    --tiktok-secondary: #FF0050;
    --tiktok-bg: rgba(0, 242, 234, 0.15);
    --instagram-orange: #F58529;
    --instagram-pink: #DD2A7B;
    --instagram-purple: #8134AF;
    --instagram-bg: rgba(221, 42, 123, 0.15);
    --youtube-red: #FF0000;
    --youtube-bg: rgba(255, 0, 0, 0.15);

    /* Functional */
    --safe-green: #00FF88;
    --danger-orange: #FF6B35;
    --accent-blue: #3B82F6;

    /* Spacing */
    --sp-xs: 4px;
    --sp-sm: 8px;
    --sp-md: 16px;
    --sp-lg: 24px;
    --sp-xl: 32px;
    --sp-2xl: 48px;

    /* Radii */
    --r-sm: 6px;
    --r-md: 10px;
    --r-lg: 16px;
    --r-xl: 24px;
    --r-pill: 9999px;

    /* Fonts */
    --font-ui: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
    --font-mono: 'JetBrains Mono', 'Fira Code', monospace;

    /* Transitions */
    --transition-fast: 150ms ease;
    --transition-med: 250ms ease;
    --transition-slow: 400ms ease;

    /* Viewport sizing */
    --viewport-width: min(360px, 85vw);
}

/* ========================================
   RESET & BASE
   ======================================== */
*, *::before, *::after {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

html {
    font-size: 16px;
    -webkit-text-size-adjust: 100%;
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-ui);
    background: var(--bg-body);
    color: var(--text-primary);
    line-height: 1.6;
    min-height: 100vh;
    overflow-x: hidden;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

img {
    display: block;
    max-width: 100%;
}

button {
    cursor: pointer;
    border: none;
    background: none;
    font-family: inherit;
    color: inherit;
}

.sr-only {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    border: 0;
}

.hidden {
    display: none !important;
}

/* ========================================
   HEADER
   ======================================== */
#site-header {
    background: linear-gradient(180deg, rgba(30, 30, 30, 0.95) 0%, rgba(13, 13, 13, 0.98) 100%);
    border-bottom: 1px solid var(--border-subtle);
    padding: var(--sp-md) var(--sp-lg);
    position: sticky;
    top: 0;
    z-index: 100;
    backdrop-filter: blur(16px);
    -webkit-backdrop-filter: blur(16px);
}

.header-inner {
    max-width: 1400px;
    margin: 0 auto;
    display: flex;
    align-items: center;
    gap: var(--sp-md);
    flex-wrap: wrap;
}

.logo {
    display: flex;
    align-items: center;
    gap: var(--sp-sm);
}

.logo-icon {
    font-size: 1.5rem;
    filter: drop-shadow(0 0 8px rgba(0, 255, 136, 0.4));
}

.logo h1 {
    font-size: 1.3rem;
    font-weight: 700;
    letter-spacing: -0.02em;
    line-height: 1.2;
}

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

.logo-sub {
    font-weight: 400;
    color: var(--text-secondary);
    -webkit-text-fill-color: var(--text-secondary);
}

.tagline {
    font-size: 0.8rem;
    color: var(--text-muted);
    margin-left: auto;
}

/* ========================================
   AD PLACEHOLDERS
   ======================================== */
.ad-container {
    display: flex;
    justify-content: center;
    padding: var(--sp-sm) 0;
}

.ad-placeholder {
    border: 1px dashed var(--border-medium);
    background: rgba(42, 42, 42, 0.3);
    color: var(--text-dim);
    font-size: 0.7rem;
    font-family: var(--font-mono);
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: var(--r-sm);
}

.ad-mobile .ad-placeholder {
    width: 320px;
    height: 50px;
}

.ad-desktop .ad-placeholder {
    width: 728px;
    height: 90px;
}

/* Mobile: show mobile ad, hide desktop ad */
.ad-desktop {
    display: none;
}

/* ========================================
   MAIN LAYOUT
   ======================================== */
#app-main {
    max-width: 1400px;
    margin: 0 auto;
    padding: var(--sp-md);
}

.app-layout {
    display: flex;
    flex-direction: column;
    gap: var(--sp-lg);
}

/* ========================================
   CONFIG PANEL (Mobile = bottom drawer)
   ======================================== */
.config-panel {
    background: var(--bg-card);
    border-radius: var(--r-lg);
    border: 1px solid var(--border-subtle);
    overflow: hidden;
    order: 2;
}

.panel-toggle {
    display: flex;
    align-items: center;
    gap: var(--sp-sm);
    width: 100%;
    padding: var(--sp-md);
    background: var(--bg-card);
    color: var(--text-primary);
    font-size: 0.95rem;
    font-weight: 600;
    border-bottom: 1px solid var(--border-subtle);
}

.toggle-chevron {
    margin-left: auto;
    transition: transform var(--transition-med);
    font-size: 0.7rem;
}

.panel-toggle[aria-expanded="true"] .toggle-chevron {
    transform: rotate(180deg);
}

.panel-body {
    padding: var(--sp-md);
    display: none;
}

.panel-body.open {
    display: block;
    animation: slideDown 0.3s ease;
}

@keyframes slideDown {
    from { opacity: 0; transform: translateY(-8px); }
    to { opacity: 1; transform: translateY(0); }
}

/* Config sections */
.config-section {
    margin-bottom: var(--sp-md);
}

.config-title {
    font-size: 0.85rem;
    font-weight: 600;
    color: var(--text-secondary);
    text-transform: uppercase;
    letter-spacing: 0.06em;
    margin-bottom: var(--sp-sm);
}

.config-divider {
    border: none;
    border-top: 1px solid var(--border-subtle);
    margin: var(--sp-md) 0;
}

.config-row {
    margin-bottom: var(--sp-md);
}

.config-label {
    display: block;
    font-size: 0.82rem;
    color: var(--text-secondary);
    margin-bottom: var(--sp-xs);
    font-weight: 500;
}

.config-label-sm {
    font-size: 0.75rem;
    color: var(--text-muted);
    margin-bottom: var(--sp-xs);
    display: block;
}

.toggle-row {
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.toggle-row .config-label {
    margin-bottom: 0;
}

/* ========================================
   DROP ZONE
   ======================================== */
.drop-zone {
    border: 2px dashed var(--border-medium);
    border-radius: var(--r-md);
    padding: var(--sp-xl) var(--sp-md);
    text-align: center;
    cursor: pointer;
    transition: all var(--transition-med);
    background: var(--bg-input);
    position: relative;
    min-height: 100px;
}

.drop-zone:hover,
.drop-zone:focus-visible {
    border-color: var(--safe-green);
    background: rgba(0, 255, 136, 0.04);
}

.drop-zone.drag-over {
    border-color: var(--safe-green);
    background: rgba(0, 255, 136, 0.08);
    transform: scale(1.01);
    box-shadow: 0 0 24px rgba(0, 255, 136, 0.15);
}

.drop-zone.has-file {
    border-color: var(--tiktok-primary);
    border-style: solid;
    background: rgba(0, 242, 234, 0.05);
}

.drop-icon {
    font-size: 2rem;
    display: block;
    margin-bottom: var(--sp-sm);
}

.drop-text {
    font-size: 0.9rem;
    font-weight: 600;
    color: var(--text-primary);
}

.drop-subtext {
    font-size: 0.75rem;
    color: var(--text-muted);
    margin-top: 2px;
}

.upload-actions {
    display: flex;
    gap: var(--sp-sm);
    margin-top: var(--sp-sm);
}

.canvas-color-row {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-top: var(--sp-sm);
    padding: var(--sp-sm) var(--sp-md);
    background: var(--bg-input);
    border-radius: var(--r-sm);
}

.canvas-color-row .config-label {
    margin-bottom: 0;
}

.color-input {
    -webkit-appearance: none;
    appearance: none;
    width: 36px;
    height: 28px;
    border: 2px solid var(--border-medium);
    border-radius: var(--r-sm);
    cursor: pointer;
    background: transparent;
    padding: 0;
}

.color-input::-webkit-color-swatch-wrapper {
    padding: 0;
}

.color-input::-webkit-color-swatch {
    border: none;
    border-radius: 3px;
}

/* ========================================
   BUTTONS
   ======================================== */
.btn {
    display: inline-flex;
    align-items: center;
    gap: var(--sp-sm);
    padding: var(--sp-sm) var(--sp-md);
    border-radius: var(--r-md);
    font-size: 0.82rem;
    font-weight: 600;
    transition: all var(--transition-fast);
    white-space: nowrap;
    flex: 1;
    justify-content: center;
}

.btn-primary {
    background: linear-gradient(135deg, var(--safe-green), #00cc6a);
    color: #0D0D0D;
    box-shadow: 0 2px 12px rgba(0, 255, 136, 0.2);
}

.btn-primary:hover {
    box-shadow: 0 4px 20px rgba(0, 255, 136, 0.35);
    transform: translateY(-1px);
}

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

.btn-secondary:hover {
    border-color: var(--text-muted);
    background: var(--bg-card-hover);
}

.btn-ghost {
    color: var(--text-muted);
    font-weight: 500;
}

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

.btn:disabled {
    opacity: 0.3;
    cursor: not-allowed;
    transform: none !important;
}

.export-btns {
    display: flex;
    flex-direction: column;
    gap: var(--sp-sm);
}

/* ========================================
   PLATFORM TOGGLE BUTTONS
   ======================================== */
.platform-toggles {
    display: flex;
    flex-direction: column;
    gap: var(--sp-sm);
}

.platform-btn {
    display: flex;
    align-items: center;
    gap: var(--sp-sm);
    padding: var(--sp-sm) var(--sp-md);
    border-radius: var(--r-md);
    border: 1px solid var(--border-subtle);
    background: var(--bg-input);
    transition: all var(--transition-med);
    position: relative;
    overflow: hidden;
}

.platform-btn::before {
    content: '';
    position: absolute;
    inset: 0;
    opacity: 0;
    transition: opacity var(--transition-med);
    border-radius: inherit;
}

.platform-btn[data-platform="tiktok"]::before {
    background: linear-gradient(135deg, rgba(0, 242, 234, 0.12), rgba(255, 0, 80, 0.08));
}

.platform-btn[data-platform="instagram"]::before {
    background: linear-gradient(135deg, rgba(245, 133, 41, 0.1), rgba(221, 42, 123, 0.12), rgba(129, 52, 175, 0.1));
}

.platform-btn[data-platform="youtube"]::before {
    background: linear-gradient(135deg, rgba(255, 0, 0, 0.12), rgba(255, 0, 0, 0.06));
}

.platform-btn:hover {
    border-color: var(--border-medium);
    background: var(--bg-card-hover);
}

.platform-btn[aria-pressed="true"]::before {
    opacity: 1;
}

.platform-btn[aria-pressed="true"][data-platform="tiktok"] {
    border-color: var(--tiktok-primary);
    box-shadow: 0 0 16px rgba(0, 242, 234, 0.2), inset 0 0 16px rgba(0, 242, 234, 0.05);
}

.platform-btn[aria-pressed="true"][data-platform="instagram"] {
    border-color: var(--instagram-pink);
    box-shadow: 0 0 16px rgba(221, 42, 123, 0.2), inset 0 0 16px rgba(221, 42, 123, 0.05);
}

.platform-btn[aria-pressed="true"][data-platform="youtube"] {
    border-color: var(--youtube-red);
    box-shadow: 0 0 16px rgba(255, 0, 0, 0.2), inset 0 0 16px rgba(255, 0, 0, 0.05);
}

.platform-icon {
    font-size: 1.2rem;
}

.platform-name {
    font-size: 0.9rem;
    font-weight: 600;
    position: relative;
    z-index: 1;
}

.platform-indicator {
    margin-left: auto;
    width: 8px;
    height: 8px;
    border-radius: 50%;
    background: var(--border-medium);
    transition: all var(--transition-med);
    position: relative;
    z-index: 1;
}

.platform-btn[aria-pressed="true"][data-platform="tiktok"] .platform-indicator {
    background: var(--tiktok-primary);
    box-shadow: 0 0 8px var(--tiktok-primary);
}

.platform-btn[aria-pressed="true"][data-platform="instagram"] .platform-indicator {
    background: var(--instagram-pink);
    box-shadow: 0 0 8px var(--instagram-pink);
}

.platform-btn[aria-pressed="true"][data-platform="youtube"] .platform-indicator {
    background: var(--youtube-red);
    box-shadow: 0 0 8px var(--youtube-red);
}

/* ========================================
   TOGGLE SWITCH
   ======================================== */
.switch {
    position: relative;
    width: 42px;
    height: 24px;
    flex-shrink: 0;
}

.switch input {
    opacity: 0;
    width: 0;
    height: 0;
}

.switch-slider {
    position: absolute;
    inset: 0;
    background: var(--bg-input);
    border: 1px solid var(--border-medium);
    border-radius: var(--r-pill);
    transition: all var(--transition-med);
    cursor: pointer;
}

.switch-slider::after {
    content: '';
    position: absolute;
    top: 2px;
    left: 2px;
    width: 18px;
    height: 18px;
    background: var(--text-muted);
    border-radius: 50%;
    transition: all var(--transition-med);
}

.switch input:checked + .switch-slider {
    background: rgba(0, 255, 136, 0.15);
    border-color: var(--safe-green);
}

.switch input:checked + .switch-slider::after {
    transform: translateX(18px);
    background: var(--safe-green);
    box-shadow: 0 0 8px rgba(0, 255, 136, 0.4);
}

/* ========================================
   CUSTOM SLIDER (Range Input)
   ======================================== */
.slider-group {
    display: flex;
    align-items: center;
    gap: var(--sp-sm);
}

.custom-slider {
    -webkit-appearance: none;
    appearance: none;
    flex: 1;
    height: 6px;
    border-radius: var(--r-pill);
    background: linear-gradient(90deg, rgba(0, 255, 136, 0.2), rgba(0, 255, 136, 0.6));
    outline: none;
    transition: background var(--transition-fast);
}

.custom-slider::-webkit-slider-thumb {
    -webkit-appearance: none;
    appearance: none;
    width: 18px;
    height: 18px;
    border-radius: 50%;
    background: var(--safe-green);
    cursor: pointer;
    box-shadow: 0 0 8px rgba(0, 255, 136, 0.4);
    transition: all var(--transition-fast);
}

.custom-slider::-webkit-slider-thumb:hover {
    transform: scale(1.15);
    box-shadow: 0 0 14px rgba(0, 255, 136, 0.6);
}

.custom-slider::-moz-range-thumb {
    width: 18px;
    height: 18px;
    border-radius: 50%;
    background: var(--safe-green);
    cursor: pointer;
    border: none;
    box-shadow: 0 0 8px rgba(0, 255, 136, 0.4);
}

.slider-value {
    font-family: var(--font-mono);
    font-size: 0.8rem;
    color: var(--safe-green);
    min-width: 36px;
    text-align: right;
}

/* ========================================
   ORIENTATION BUTTONS
   ======================================== */
.orientation-btns {
    display: flex;
    gap: var(--sp-sm);
}

.orient-btn {
    flex: 1;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--sp-sm);
    padding: var(--sp-sm) var(--sp-md);
    border-radius: var(--r-md);
    border: 1px solid var(--border-subtle);
    background: var(--bg-input);
    font-size: 0.82rem;
    font-weight: 600;
    font-family: var(--font-mono);
    color: var(--text-muted);
    transition: all var(--transition-med);
}

.orient-btn.active {
    border-color: var(--safe-green);
    color: var(--safe-green);
    background: rgba(0, 255, 136, 0.06);
    box-shadow: 0 0 12px rgba(0, 255, 136, 0.1);
}

.orient-icon {
    display: inline-block;
    border: 2px solid currentColor;
    border-radius: 3px;
}

.portrait-icon {
    width: 10px;
    height: 16px;
}

.landscape-icon {
    width: 16px;
    height: 10px;
}

/* ========================================
   COMPARISON MODE SELECTORS
   ======================================== */
.compare-selectors {
    display: flex;
    align-items: flex-end;
    gap: var(--sp-sm);
    margin-top: var(--sp-sm);
}

.compare-side {
    flex: 1;
}

.compare-divider-icon {
    color: var(--text-dim);
    font-size: 1rem;
    padding-bottom: 6px;
}

.config-select {
    width: 100%;
    padding: var(--sp-sm) var(--sp-md);
    border-radius: var(--r-sm);
    border: 1px solid var(--border-subtle);
    background: var(--bg-input);
    color: var(--text-primary);
    font-family: var(--font-ui);
    font-size: 0.82rem;
    appearance: none;
    cursor: pointer;
    background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='10' height='6'%3E%3Cpath d='M0 0l5 6 5-6' fill='%23666'/%3E%3C/svg%3E");
    background-repeat: no-repeat;
    background-position: right 10px center;
    padding-right: 28px;
}

/* ========================================
   VIEWPORT AREA
   ======================================== */
.viewport-area {
    display: flex;
    flex-direction: column;
    align-items: center;
    order: 1;
}

.viewport-wrapper {
    display: flex;
    justify-content: center;
    align-items: center;
    width: 100%;
}

/* ========================================
   DEVICE FRAME
   ======================================== */
.device-frame {
    position: relative;
    padding: 0;
    transition: padding var(--transition-slow), border-radius var(--transition-slow),
                background var(--transition-slow), box-shadow var(--transition-slow);
}

.device-frame.show-frame {
    padding: 12px;
    background: linear-gradient(145deg, #2A2A2A, #1A1A1A);
    border-radius: 36px;
    box-shadow:
        0 0 0 2px #333,
        0 0 0 4px #222,
        0 20px 60px rgba(0, 0, 0, 0.6),
        inset 0 1px 0 rgba(255, 255, 255, 0.05);
}

.device-frame.show-frame::before {
    content: '';
    position: absolute;
    top: 6px;
    left: 50%;
    transform: translateX(-50%);
    width: 60px;
    height: 5px;
    background: #333;
    border-radius: 3px;
    z-index: 5;
}

/* ========================================
   PHONE VIEWPORT
   ======================================== */
.phone-viewport {
    position: relative;
    overflow: hidden;
    background: #111;
    border-radius: var(--r-lg);
    box-shadow:
        0 0 40px rgba(0, 0, 0, 0.5),
        0 0 80px rgba(0, 0, 0, 0.3);
}

.phone-viewport.portrait {
    width: var(--viewport-width);
    aspect-ratio: 9 / 16;
}

.phone-viewport.landscape {
    width: min(640px, 90vw);
    aspect-ratio: 16 / 9;
}

.show-frame .phone-viewport {
    border-radius: 24px;
}

.viewport-image {
    position: absolute;
    inset: 0;
    width: 100%;
    height: 100%;
    object-fit: cover;
    z-index: 1;
}

.viewport-image[src=""],
.viewport-image:not([src]) {
    display: none;
}

.viewport-canvas-bg {
    position: absolute;
    inset: 0;
    z-index: 0;
    background: #2A2A2A;
    display: none;
}

.viewport-canvas-bg.active {
    display: block;
}

/* ========================================
   OVERLAY CONTAINER & ZONES
   ======================================== */
.overlay-container {
    position: absolute;
    inset: 0;
    z-index: 2;
    pointer-events: none;
}

.overlay-zone {
    position: absolute;
    border-radius: 4px;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: opacity var(--transition-med);
    pointer-events: none;
    overflow: hidden;
}

.overlay-zone::after {
    content: '';
    position: absolute;
    inset: 0;
    border-radius: inherit;
    opacity: 0;
    animation: zonePulse 2s ease-in-out;
}

@keyframes zonePulse {
    0% { opacity: 0.6; transform: scale(1.05); }
    50% { opacity: 0.3; }
    100% { opacity: 0; transform: scale(1); }
}

.zone-label {
    font-size: 8px;
    font-weight: 600;
    font-family: var(--font-mono);
    color: rgba(255, 255, 255, 0.9);
    text-shadow: 0 1px 3px rgba(0, 0, 0, 0.8);
    z-index: 1;
    text-align: center;
    line-height: 1.2;
    padding: 2px 4px;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
    max-width: 100%;
}

/* Platform-specific overlay colors */
.overlay-zone.tiktok {
    background: rgba(0, 242, 234, var(--overlay-opacity, 0.4));
    border: 1px solid rgba(0, 242, 234, 0.5);
}

.overlay-zone.tiktok::after {
    background: rgba(0, 242, 234, 0.3);
}

.overlay-zone.instagram {
    background: rgba(221, 42, 123, var(--overlay-opacity, 0.4));
    border: 1px solid rgba(221, 42, 123, 0.5);
}

.overlay-zone.instagram::after {
    background: rgba(221, 42, 123, 0.3);
}

.overlay-zone.youtube {
    background: rgba(255, 0, 0, var(--overlay-opacity, 0.4));
    border: 1px solid rgba(255, 0, 0, 0.5);
}

.overlay-zone.youtube::after {
    background: rgba(255, 0, 0, 0.3);
}

.overlay-zone.overlap-zone {
    background: rgba(255, 107, 53, var(--overlay-opacity, 0.4));
    border: 2px solid rgba(255, 107, 53, 0.7);
    z-index: 3;
}

/* ========================================
   SAFE ZONE RECTANGLE
   ======================================== */
.safe-zone-rect {
    position: absolute;
    z-index: 4;
    border: 2px dashed var(--safe-green);
    border-radius: 4px;
    pointer-events: none;
    animation: marchingAnts 1s linear infinite;
    background: transparent;
}

@keyframes marchingAnts {
    0% { border-dash-offset: 0; }
    100% { border-dash-offset: 16; }
}

/* Use SVG-based marching ants for better browser support */
.safe-zone-rect {
    border: none;
    background-image:
        repeating-linear-gradient(0deg, var(--safe-green) 0, var(--safe-green) 6px, transparent 6px, transparent 12px),
        repeating-linear-gradient(90deg, var(--safe-green) 0, var(--safe-green) 6px, transparent 6px, transparent 12px),
        repeating-linear-gradient(180deg, var(--safe-green) 0, var(--safe-green) 6px, transparent 6px, transparent 12px),
        repeating-linear-gradient(270deg, var(--safe-green) 0, var(--safe-green) 6px, transparent 6px, transparent 12px);
    background-size: 2px 100%, 100% 2px, 2px 100%, 100% 2px;
    background-position: 0 0, 0 0, 100% 0, 0 100%;
    background-repeat: no-repeat;
    animation: marchAnts 0.5s linear infinite;
}

@keyframes marchAnts {
    0% {
        background-image:
            repeating-linear-gradient(0deg, var(--safe-green) 0, var(--safe-green) 6px, transparent 6px, transparent 12px),
            repeating-linear-gradient(90deg, var(--safe-green) 0, var(--safe-green) 6px, transparent 6px, transparent 12px),
            repeating-linear-gradient(180deg, var(--safe-green) 0, var(--safe-green) 6px, transparent 6px, transparent 12px),
            repeating-linear-gradient(270deg, var(--safe-green) 0, var(--safe-green) 6px, transparent 6px, transparent 12px);
    }
    50% {
        background-image:
            repeating-linear-gradient(0deg, transparent 0, transparent 6px, var(--safe-green) 6px, var(--safe-green) 12px),
            repeating-linear-gradient(90deg, transparent 0, transparent 6px, var(--safe-green) 6px, var(--safe-green) 12px),
            repeating-linear-gradient(180deg, transparent 0, transparent 6px, var(--safe-green) 6px, var(--safe-green) 12px),
            repeating-linear-gradient(270deg, transparent 0, transparent 6px, var(--safe-green) 6px, var(--safe-green) 12px);
    }
    100% {
        background-image:
            repeating-linear-gradient(0deg, var(--safe-green) 0, var(--safe-green) 6px, transparent 6px, transparent 12px),
            repeating-linear-gradient(90deg, var(--safe-green) 0, var(--safe-green) 6px, transparent 6px, transparent 12px),
            repeating-linear-gradient(180deg, var(--safe-green) 0, var(--safe-green) 6px, transparent 6px, transparent 12px),
            repeating-linear-gradient(270deg, var(--safe-green) 0, var(--safe-green) 6px, transparent 6px, transparent 12px);
    }
}

.safe-zone-label {
    position: absolute;
    top: 6px;
    left: 6px;
    font-family: var(--font-mono);
    font-size: 9px;
    font-weight: 700;
    color: var(--safe-green);
    background: rgba(0, 0, 0, 0.6);
    padding: 2px 6px;
    border-radius: 3px;
    letter-spacing: 0.1em;
    white-space: nowrap;
}

.safe-zone-dims {
    position: absolute;
    bottom: 6px;
    left: 6px;
    font-family: var(--font-mono);
    font-size: 7px;
    font-weight: 500;
    color: var(--safe-green);
    background: rgba(0, 0, 0, 0.6);
    padding: 2px 6px;
    border-radius: 3px;
    opacity: 0.9;
    white-space: nowrap;
}

/* ========================================
   COMPARISON MODE
   ======================================== */
.compare-viewport-wrapper {
    display: flex;
    gap: var(--sp-sm);
    justify-content: center;
    align-items: stretch;
    width: 100%;
}

.compare-half {
    flex: 1;
    display: flex;
    flex-direction: column;
    align-items: center;
    max-width: 280px;
}

.compare-label {
    font-family: var(--font-mono);
    font-size: 0.75rem;
    font-weight: 700;
    text-align: center;
    padding: var(--sp-xs) var(--sp-sm);
    margin-bottom: var(--sp-sm);
    border-radius: var(--r-sm);
    text-transform: uppercase;
    letter-spacing: 0.06em;
}

#compare-label-left {
    color: var(--tiktok-primary);
    background: rgba(0, 242, 234, 0.08);
    border: 1px solid rgba(0, 242, 234, 0.2);
}

#compare-label-right {
    color: var(--instagram-pink);
    background: rgba(221, 42, 123, 0.08);
    border: 1px solid rgba(221, 42, 123, 0.2);
}

.compare-divider {
    width: 2px;
    background: linear-gradient(180deg, transparent, var(--border-medium), transparent);
    margin: 20px 0;
    align-self: stretch;
}

.compare-frame {
    width: 100%;
}

.compare-vp {
    width: 100% !important;
}

/* ========================================
   PLATFORM LEGEND
   ======================================== */
.platform-legend {
    width: 100%;
    max-width: 500px;
    margin-top: var(--sp-lg);
    padding: var(--sp-md);
    background: var(--bg-card);
    border-radius: var(--r-md);
    border: 1px solid var(--border-subtle);
}

.legend-title {
    font-size: 0.75rem;
    font-weight: 600;
    color: var(--text-muted);
    text-transform: uppercase;
    letter-spacing: 0.08em;
    margin-bottom: var(--sp-sm);
}

.legend-items {
    display: flex;
    flex-wrap: wrap;
    gap: var(--sp-sm);
}

.legend-empty {
    font-size: 0.82rem;
    color: var(--text-dim);
    font-style: italic;
}

.legend-item {
    display: flex;
    align-items: center;
    gap: 6px;
    font-size: 0.78rem;
    font-weight: 500;
}

.legend-swatch {
    width: 12px;
    height: 12px;
    border-radius: 3px;
    flex-shrink: 0;
}

.legend-swatch.tiktok { background: var(--tiktok-primary); }
.legend-swatch.instagram { background: var(--instagram-pink); }
.legend-swatch.youtube { background: var(--youtube-red); }
.legend-swatch.overlap { background: var(--danger-orange); }
.legend-swatch.safezone {
    background: transparent;
    border: 2px dashed var(--safe-green);
}

/* ========================================
   HOW-TO SECTION
   ======================================== */
.how-to-section {
    max-width: 1000px;
    margin: var(--sp-2xl) auto;
    padding: 0 var(--sp-md);
}

.section-title {
    text-align: center;
    font-size: 1.5rem;
    font-weight: 700;
    margin-bottom: var(--sp-xl);
    color: var(--text-primary);
}

.steps-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: var(--sp-md);
}

.step-card {
    background: var(--bg-card);
    border: 1px solid var(--border-subtle);
    border-radius: var(--r-lg);
    padding: var(--sp-lg);
    text-align: center;
    position: relative;
    transition: all var(--transition-med);
}

.step-card:hover {
    border-color: var(--border-medium);
    transform: translateY(-2px);
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.3);
}

.step-number {
    position: absolute;
    top: var(--sp-sm);
    left: var(--sp-sm);
    width: 24px;
    height: 24px;
    background: rgba(0, 255, 136, 0.1);
    color: var(--safe-green);
    border-radius: 50%;
    font-size: 0.7rem;
    font-weight: 700;
    font-family: var(--font-mono);
    display: flex;
    align-items: center;
    justify-content: center;
    border: 1px solid rgba(0, 255, 136, 0.2);
}

.step-icon {
    font-size: 2rem;
    margin-bottom: var(--sp-sm);
}

.step-card h3 {
    font-size: 1rem;
    font-weight: 700;
    margin-bottom: var(--sp-xs);
}

.step-card p {
    font-size: 0.82rem;
    color: var(--text-secondary);
    line-height: 1.5;
}

/* ========================================
   FOOTER
   ======================================== */
#site-footer {
    border-top: 1px solid var(--border-subtle);
    padding: var(--sp-xl) var(--sp-md);
    text-align: center;
}

.footer-inner {
    max-width: 600px;
    margin: 0 auto;
}

.footer-inner p {
    font-size: 0.78rem;
    color: var(--text-muted);
    line-height: 1.5;
}

.footer-copy {
    margin-top: var(--sp-sm);
    color: var(--text-dim) !important;
    font-size: 0.7rem !important;
}

/* ========================================
   TOAST NOTIFICATION
   ======================================== */
.toast {
    position: fixed;
    bottom: 24px;
    left: 50%;
    transform: translateX(-50%) translateY(100px);
    background: var(--bg-card);
    border: 1px solid var(--border-medium);
    color: var(--text-primary);
    padding: var(--sp-sm) var(--sp-lg);
    border-radius: var(--r-pill);
    font-size: 0.82rem;
    font-weight: 500;
    z-index: 1000;
    opacity: 0;
    transition: all var(--transition-med);
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.5);
    white-space: nowrap;
}

.toast.show {
    opacity: 1;
    transform: translateX(-50%) translateY(0);
}

.toast.success {
    border-color: var(--safe-green);
    box-shadow: 0 8px 32px rgba(0, 255, 136, 0.15);
}

.toast.error {
    border-color: var(--danger-orange);
    box-shadow: 0 8px 32px rgba(255, 107, 53, 0.15);
}

/* ========================================
   RESPONSIVE: TABLET (>=640px)
   ======================================== */
@media (min-width: 640px) {
    :root {
        --viewport-width: 380px;
    }

    .steps-grid {
        grid-template-columns: repeat(2, 1fr);
    }

    .compare-half {
        max-width: 300px;
    }
}

/* ========================================
   RESPONSIVE: DESKTOP (>=960px)
   ======================================== */
@media (min-width: 960px) {
    :root {
        --viewport-width: 400px;
    }

    /* Show desktop ad, hide mobile ad */
    .ad-desktop {
        display: flex;
    }
    .ad-mobile {
        display: none;
    }

    /* Sidebar layout */
    .app-layout {
        flex-direction: row;
        align-items: flex-start;
    }

    .config-panel {
        width: 300px;
        min-width: 300px;
        order: 0;
        position: sticky;
        top: 80px;
        max-height: calc(100vh - 100px);
        overflow-y: auto;
        scrollbar-width: thin;
        scrollbar-color: var(--border-medium) transparent;
    }

    .config-panel::-webkit-scrollbar {
        width: 4px;
    }

    .config-panel::-webkit-scrollbar-track {
        background: transparent;
    }

    .config-panel::-webkit-scrollbar-thumb {
        background: var(--border-medium);
        border-radius: 2px;
    }

    /* Hide mobile drawer toggle on desktop */
    .panel-toggle {
        display: none;
    }

    .panel-body {
        display: block !important;
    }

    .viewport-area {
        flex: 1;
        order: 1;
    }

    .steps-grid {
        grid-template-columns: repeat(4, 1fr);
    }

    .compare-half {
        max-width: 360px;
    }
}

/* ========================================
   RESPONSIVE: WIDE (>=1200px)
   ======================================== */
@media (min-width: 1200px) {
    :root {
        --viewport-width: 420px;
    }

    .config-panel {
        width: 320px;
        min-width: 320px;
    }
}