:root {
    --accent: 99 102 241;
    --grid-opacity: 0.4;
    --glass-blur: 12px;
    
    /* Light theme (default) */
    --bg-primary: #ffffff;
    --bg-secondary: #fafafa;
    --bg-tertiary: #f4f4f5;
    --fg-primary: #18181b;
    --fg-secondary: #71717a;
    --fg-muted: #a1a1aa;
    --border-primary: #e4e4e7;
    --border-secondary: #d4d4d8;
    --accent-primary: #84cc16;
    --accent-hover: #65a30d;
    --glass-bg: rgba(255, 255, 255, 0.8);
    --glass-border: rgba(228, 228, 231, 0.5);
    --shadow-color: rgba(0, 0, 0, 0.08);
    --overlay-bg: rgba(0, 0, 0, 0.4);
    --input-bg: #ffffff;
    --input-border: #e4e4e7;
    --dropdown-bg: #ffffff;
    --dropdown-hover: #f4f4f5;
    --btn-primary-bg: #18181b;
    --btn-primary-hover: #84cc16;
    --btn-secondary-bg: #ffffff;
    --btn-secondary-hover: #f4f4f5;
    --bg-inverse: #18181b;
}

[data-theme="dark"] {
    --bg-primary: #18181b;
    --bg-secondary: #1f1f23;
    --bg-tertiary: #27272a;
    --fg-primary: #fafafa;
    --fg-secondary: #a1a1aa;
    --fg-muted: #71717a;
    --border-primary: #3f3f46;
    --border-secondary: #52525b;
    --accent-primary: #84cc16;
    --accent-hover: #a3e635;
    --glass-bg: rgba(24, 24, 27, 0.8);
    --glass-border: rgba(63, 63, 70, 0.5);
    --shadow-color: rgba(0, 0, 0, 0.3);
    --overlay-bg: rgba(0, 0, 0, 0.6);
    --input-bg: #27272a;
    --input-border: #3f3f46;
    --dropdown-bg: #27272a;
    --dropdown-hover: #3f3f46;
    --btn-primary-bg: #fafafa;
    --btn-primary-hover: #84cc16;
    --btn-secondary-bg: #27272a;
    --btn-secondary-hover: #3f3f46;
    --bg-inverse: #27272a;
}

html {
    transition: background-color 0.3s ease, color 0.3s ease;
}

body {
    font-family: 'Inter', sans-serif;
    background-color: var(--bg-primary);
    color: var(--fg-primary);
    overflow-x: hidden;
}

.optical-grid-surface {
    background-image: radial-gradient(var(--border-primary) 0.5px, transparent 0.5px);
    background-size: 20px 20px;
    position: relative;
}

.hero-headline {
    font-size: clamp(2.5rem, 8vw, 4.5rem);
    line-height: 1.1;
    font-weight: 800;
    letter-spacing: -0.04em;
}

.section-headline {
    font-size: clamp(1.75rem, 4vw, 2.5rem);
    line-height: 1.2;
    font-weight: 700;
    letter-spacing: -0.02em;
}

.animate-enter {
    opacity: 0;
    transform: translateY(30px);
    transition: opacity 0.8s cubic-bezier(0.16, 1, 0.3, 1), transform 0.8s cubic-bezier(0.16, 1, 0.3, 1);
}

.animate-enter.is-visible {
    opacity: 1;
    transform: translateY(0);
}

.word-reveal-parent {
    overflow: hidden;
    display: inline-block;
    vertical-align: bottom;
    padding-bottom: 0.15em;
}

.animate-word-enter {
    display: inline-block;
    transform: translateY(110%);
    transition: transform 0.8s cubic-bezier(0.16, 1, 0.3, 1);
}

.hero-headline.is-visible .animate-word-enter {
    transform: translateY(0);
}

.custom-scrollbar::-webkit-scrollbar {
    width: 4px;
}
.custom-scrollbar::-webkit-scrollbar-track {
    background: var(--bg-tertiary);
}
.custom-scrollbar::-webkit-scrollbar-thumb {
    background: var(--border-primary);
    border-radius: 2px;
}
.custom-scrollbar::-webkit-scrollbar-thumb:hover {
    background: var(--accent-primary);
}

.glass-panel {
    background: var(--glass-bg);
    backdrop-filter: blur(var(--glass-blur));
    border: 1px solid var(--glass-border);
}

.accordion-content {
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.3s cubic-bezier(0.16, 1, 0.3, 1);
}
.accordion-item.active .accordion-content {
    max-height: 1000px;
}
.accordion-header svg {
    transition: transform 0.3s ease;
}
.accordion-item.active .accordion-header svg {
    transform: rotate(180deg);
}

input[type="range"] {
    accent-color: var(--accent-primary);
}

.btn-primary {
    background: var(--accent-primary);
    color: #ffffff;
    transition: all 300ms cubic-bezier(0.16, 1, 0.3, 1);
}
.btn-primary:hover {
    background: var(--accent-hover);
    transform: translateY(-1px);
}
.btn-primary:active {
    transform: translateY(0) scale(0.97);
}

.lang-btn {
    background: var(--btn-secondary-bg);
    color: var(--fg-secondary);
}
.lang-btn:hover {
    background: var(--btn-secondary-hover);
}

/* Hide scrollbar for template carousel */
.no-scrollbar {
    -ms-overflow-style: none;
    scrollbar-width: none;
}
.no-scrollbar::-webkit-scrollbar {
    display: none;
}

/* QR preview responsive */
#qr-preview {
    width: 100%;
    max-width: 300px;
    margin: 0 auto;
}
#qr-preview svg,
#qr-preview canvas {
    max-width: 100%;
    height: auto;
}

/* Mobile Menu */
.mobile-menu {
    position: fixed;
    inset: 0;
    z-index: 100;
    background: var(--overlay-bg);
    backdrop-filter: blur(4px);
    opacity: 0;
    pointer-events: none;
    transition: opacity 0.3s ease;
}
.mobile-menu.is-open {
    opacity: 1;
    pointer-events: all;
}
.mobile-menu-panel {
    position: absolute;
    top: 0;
    right: 0;
    width: 280px;
    height: 100%;
    background: var(--bg-secondary);
    padding: 5rem 1.5rem 2rem;
    transform: translateX(100%);
    transition: transform 0.3s cubic-bezier(0.16, 1, 0.3, 1);
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}
.mobile-menu.is-open .mobile-menu-panel {
    transform: translateX(0);
}
.mobile-menu-link {
    display: block;
    padding: 0.75rem 1rem;
    font-size: 0.9375rem;
    font-weight: 600;
    color: var(--fg-primary);
    border-bottom: 1px solid var(--bg-tertiary);
    transition: color 0.2s;
}
.mobile-menu-link:hover {
    color: var(--accent-primary);
}
.mobile-menu-link.primary {
    background: var(--bg-inverse);
    color: #fff;
    text-align: center;
    text-transform: uppercase;
    letter-spacing: 0.1em;
    font-size: 0.75rem;
    margin-top: auto;
    border-bottom: none;
}
.mobile-menu-link.primary:hover {
    background: var(--accent-primary);
}

/* Bigger touch targets on mobile */
@media (max-width: 639px) {
    .lang-btn {
        padding: 0.5rem 0.75rem;
        font-size: 0.75rem;
    }
    .type-btn {
        padding: 0.625rem 0.5rem;
        font-size: 0.8125rem;
    }
    #qr-preview {
        max-width: 240px;
    }
}

/* Color picker bottom-safe positioning */
@media (max-height: 600px) {
    .clr-popup {
        top: auto;
        bottom: calc(100% + 6px);
    }
}

@supports (padding: env(safe-area-inset-bottom)) {
    .mobile-menu-panel {
        padding-bottom: calc(2rem + env(safe-area-inset-bottom));
    }
}

@media (min-width: 1024px) {
    .sticky-preview {
        position: sticky;
        top: 2rem;
    }
}

.donate-overlay {
    position: fixed;
    inset: 0;
    z-index: 999;
    background: var(--overlay-bg);
    backdrop-filter: blur(4px);
    display: flex;
    align-items: center;
    justify-content: center;
    opacity: 0;
    pointer-events: none;
    transition: opacity 0.4s cubic-bezier(0.16, 1, 0.3, 1);
}
.donate-overlay.is-open {
    opacity: 1;
    pointer-events: all;
}
.donate-modal {
    background: var(--bg-secondary);
    max-width: 380px;
    width: 90%;
    padding: 2rem;
    text-align: center;
    transform: translateY(20px) scale(0.96);
    transition: transform 0.4s cubic-bezier(0.16, 1, 0.3, 1);
}
.donate-overlay.is-open .donate-modal {
    transform: translateY(0) scale(1);
}
.donate-modal .emoji {
    font-size: 2.5rem;
    margin-bottom: 0.75rem;
}
.donate-modal h3 {
    font-size: 1.125rem;
    font-weight: 700;
    margin-bottom: 0.5rem;
}
.donate-modal p {
    font-size: 0.8125rem;
    color: var(--fg-secondary);
    line-height: 1.6;
    margin-bottom: 1.5rem;
}
.donate-modal .btn-donate {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.75rem 1.5rem;
    background: var(--bg-inverse);
    color: #fff;
    font-size: 0.75rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.1em;
    transition: all 0.3s ease;
    text-decoration: none;
}
.donate-modal .btn-donate:hover {
    background: var(--accent-primary);
}
.donate-modal .btn-close {
    margin-top: 1rem;
    background: none;
    border: none;
    font-size: 0.75rem;
    color: var(--fg-muted);
    cursor: pointer;
    text-decoration: underline;
}
.donate-modal .btn-close:hover {
    color: var(--fg-primary);
}

.clr-trigger {
    width: 2.5rem;
    height: 2.5rem;
    border-radius: 0;
    border: 1px solid var(--border-primary);
    cursor: pointer;
    position: relative;
    flex-shrink: 0;
    transition: border-color 0.2s;
}
.clr-trigger:hover {
    border-color: var(--accent-primary);
}
.clr-trigger.is-active {
    border-color: var(--accent-primary);
    box-shadow: 0 0 0 2px rgba(99,102,241,0.2);
}

.clr-popup {
    position: absolute;
    top: calc(100% + 6px);
    left: 0;
    z-index: 50;
    background: var(--dropdown-bg);
    border: 1px solid var(--border-primary);
    box-shadow: 0 8px 24px var(--shadow-color);
    padding: 1rem;
    width: 232px;
    opacity: 0;
    pointer-events: none;
    transform: translateY(4px);
    transition: opacity 0.2s, transform 0.2s;
}
.clr-popup.is-open {
    opacity: 1;
    pointer-events: all;
    transform: translateY(0);
}
.clr-popup canvas#sv-canvas {
    width: 200px;
    height: 150px;
    border: 1px solid var(--border-primary);
    cursor: crosshair;
    display: block;
    margin-bottom: 0.5rem;
}
.clr-popup input#hue-slider {
    width: 100%;
    height: 10px;
    -webkit-appearance: none;
    appearance: none;
    border-radius: 0;
    outline: none;
    cursor: pointer;
    margin-bottom: 0.75rem;
    background: linear-gradient(to right, #f00 0%, #ff0 17%, #0f0 33%, #0ff 50%, #00f 67%, #f0f 83%, #f00 100%);
}
.clr-popup input#hue-slider::-webkit-slider-thumb {
    -webkit-appearance: none;
    appearance: none;
    width: 14px;
    height: 14px;
    border: 2px solid #fff;
    border-radius: 0;
    background: transparent;
    box-shadow: 0 0 0 1px rgba(0,0,0,0.3);
    cursor: pointer;
}
.clr-popup input#hue-slider::-moz-range-thumb {
    width: 14px;
    height: 14px;
    border: 2px solid #fff;
    border-radius: 0;
    background: transparent;
    box-shadow: 0 0 0 1px rgba(0,0,0,0.3);
    cursor: pointer;
}

.clr-swatches {
    display: grid;
    grid-template-columns: repeat(6, 1fr);
    gap: 4px;
}
.clr-swatch {
    aspect-ratio: 1;
    border: 1px solid var(--border-primary);
    cursor: pointer;
    transition: transform 0.15s, border-color 0.15s;
}
.clr-swatch:hover {
    transform: scale(1.15);
    border-color: var(--accent-primary);
    z-index: 1;
    position: relative;
}

.csel {
    position: relative;
    display: block;
    width: 100%;
    cursor: pointer;
    user-select: none;
}
.csel-trigger {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 0.5rem;
    width: 100%;
    padding: 0.375rem 0.5rem;
    background: var(--input-bg);
    border: 1px solid var(--input-border);
    font-size: 0.75rem;
    font-weight: 500;
    color: var(--fg-primary);
    cursor: pointer;
    transition: border-color 0.2s;
    line-height: 1.4;
}
.csel-trigger:hover {
    border-color: var(--accent-primary);
}
.csel-trigger svg {
    width: 14px;
    height: 14px;
    color: var(--fg-muted);
    flex-shrink: 0;
    transition: transform 0.2s;
}
.csel.is-open .csel-trigger svg {
    transform: rotate(180deg);
}
.csel.is-open .csel-trigger {
    border-color: var(--accent-primary);
}
.csel-menu {
    position: absolute;
    top: calc(100% + 2px);
    left: 0;
    right: 0;
    z-index: 40;
    background: var(--dropdown-bg);
    border: 1px solid var(--border-primary);
    box-shadow: 0 8px 24px var(--shadow-color);
    opacity: 0;
    pointer-events: none;
    transform: translateY(4px);
    transition: opacity 0.15s, transform 0.15s;
}
.csel.is-open .csel-menu {
    opacity: 1;
    pointer-events: all;
    transform: translateY(0);
}
.csel-option {
    padding: 0.5rem 0.625rem;
    font-size: 0.75rem;
    color: var(--fg-primary);
    cursor: pointer;
    transition: background 0.15s;
}
.csel-option:hover {
    background: var(--dropdown-hover);
}
.csel-option.is-selected {
    background: var(--dropdown-hover);
    font-weight: 600;
    color: var(--accent-primary);
}

/* Custom Range Slider */
input:not([type="range"]):not([type="checkbox"]):not([type="radio"]),
select, textarea {
    background-color: var(--input-bg) !important;
    color: var(--fg-primary);
    border-color: var(--input-border) !important;
}

input[type="range"] {
    -webkit-appearance: none;
    appearance: none;
    width: 100%;
    height: 4px;
    background: var(--border-primary);
    border-radius: 2px;
    outline: none;
    cursor: pointer;
}
input[type="range"]::-webkit-slider-thumb {
    -webkit-appearance: none;
    appearance: none;
    width: 18px;
    height: 18px;
    border-radius: 50%;
    background: #84cc16;
    border: 3px solid #fff;
    box-shadow: 0 1px 4px rgba(0,0,0,0.15);
    cursor: pointer;
    transition: transform 0.15s;
}
input[type="range"]::-webkit-slider-thumb:hover {
    transform: scale(1.15);
}
input[type="range"]::-moz-range-thumb {
    width: 18px;
    height: 18px;
    border-radius: 50%;
    background: #84cc16;
    border: 3px solid #fff;
    box-shadow: 0 1px 4px rgba(0,0,0,0.15);
    cursor: pointer;
}

/* Custom Checkbox */
input[type="checkbox"] {
    -webkit-appearance: none;
    appearance: none;
    width: 18px;
    height: 18px;
    border: 2px solid var(--border-secondary);
    border-radius: 4px;
    outline: none;
    cursor: pointer;
    transition: all 0.15s;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
    margin: 0;
}
input[type="checkbox"]:checked {
    background: var(--accent-primary);
    border-color: var(--accent-primary);
}
input[type="checkbox"]:checked::after {
    content: "";
    display: block;
    width: 5px;
    height: 9px;
    border: solid #fff;
    border-width: 0 2px 2px 0;
    transform: rotate(45deg);
    margin-top: -1px;
}
input[type="checkbox"]:hover {
    border-color: var(--fg-muted);
}
input[type="checkbox"]:checked:hover {
    border-color: var(--accent-hover);
    background: var(--accent-hover);
}