/* ============================================
   Percentage Calculator — Premium Design System
   ============================================ */

:root {
    /* Light Mode */
    --color-bg: #f5f6fa;
    --color-bg-alt: #ffffff;
    --color-bg-elevated: #ffffff;
    --color-surface: #f0f1f7;
    --color-surface-hover: #e5e7f0;
    --color-border: #dfe2ed;
    --color-border-subtle: #eceef5;

    --color-text-primary: #1a1d2e;
    --color-text-secondary: #5a5f7a;
    --color-text-tertiary: #8b90a8;
    --color-text-inverse: #ffffff;

    --color-primary: #3a7bd5;
    --color-primary-hover: #2d6bc4;
    --color-primary-light: rgba(58, 123, 213, 0.1);
    --color-primary-glow: rgba(58, 123, 213, 0.25);

    --color-success: #22c55e;
    --color-success-light: rgba(34, 197, 94, 0.1);

    --gradient-hero: linear-gradient(135deg, #3a7bd5 0%, #6c5ce7 100%);

    --shadow-sm: 0 1px 3px rgba(0,0,0,0.04), 0 1px 2px rgba(0,0,0,0.06);
    --shadow-md: 0 4px 14px rgba(0,0,0,0.06), 0 2px 6px rgba(0,0,0,0.04);
    --shadow-lg: 0 10px 40px rgba(0,0,0,0.08), 0 4px 12px rgba(0,0,0,0.04);

    --font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    --font-size-xs: 0.75rem;
    --font-size-sm: 0.875rem;
    --font-size-base: 1rem;
    --font-size-lg: 1.125rem;
    --font-size-xl: 1.25rem;
    --font-size-2xl: 1.5rem;
    --font-size-3xl: 1.875rem;

    --space-1: 0.25rem;
    --space-2: 0.5rem;
    --space-3: 0.75rem;
    --space-4: 1rem;
    --space-5: 1.25rem;
    --space-6: 1.5rem;
    --space-8: 2rem;
    --space-10: 2.5rem;
    --space-12: 3rem;
    --space-16: 4rem;
    --space-20: 5rem;

    --radius-sm: 0.375rem;
    --radius-md: 0.5rem;
    --radius-lg: 0.75rem;
    --radius-xl: 1rem;
    --radius-2xl: 1.25rem;
    --radius-full: 9999px;

    --transition-fast: 150ms cubic-bezier(0.4, 0, 0.2, 1);
    --transition-normal: 250ms cubic-bezier(0.4, 0, 0.2, 1);
    --transition-slow: 350ms cubic-bezier(0.4, 0, 0.2, 1);

    --max-width: 1240px;
    --header-height: 64px;
}

/* Dark Mode */
[data-theme="dark"] {
    --color-bg: #111320;
    --color-bg-alt: #161827;
    --color-bg-elevated: #1b1e30;
    --color-surface: #222540;
    --color-surface-hover: #2a2e4a;
    --color-border: #2c3050;
    --color-border-subtle: #232640;

    --color-text-primary: #eef0f6;
    --color-text-secondary: #9ea3c0;
    --color-text-tertiary: #6b7094;
    --color-text-inverse: #111320;

    --color-primary-light: rgba(58, 123, 213, 0.15);

    --shadow-sm: 0 1px 3px rgba(0,0,0,0.3);
    --shadow-md: 0 4px 14px rgba(0,0,0,0.35);
    --shadow-lg: 0 10px 40px rgba(0,0,0,0.4);
}

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

html {
    scroll-behavior: smooth;
    scroll-padding-top: var(--header-height);
    overflow-x: hidden;
    width: 100%;
}

body {
    font-family: var(--font-family);
    font-size: var(--font-size-base);
    line-height: 1.7;
    color: var(--color-text-primary);
    background-color: var(--color-bg);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    overflow-x: hidden;
    transition: background-color var(--transition-slow), color var(--transition-slow);
}

a {
    color: var(--color-primary);
    text-decoration: none;
    transition: color var(--transition-fast);
}

a:hover {
    color: var(--color-primary-hover);
}

ul { list-style: none; }
img { max-width: 100%; height: auto; }

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

input {
    font-family: inherit;
    font-size: inherit;
}

/* ============================================
   Layout
   ============================================ */
.container {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 var(--space-6);
}

/* ============================================
   Header
   ============================================ */
.header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    height: var(--header-height);
    background: rgba(248, 249, 252, 0.88);
    backdrop-filter: blur(16px) saturate(180%);
    -webkit-backdrop-filter: blur(16px) saturate(180%);
    border-bottom: 1px solid var(--color-border-subtle);
    transition: background var(--transition-slow), border-color var(--transition-slow), box-shadow var(--transition-slow);
}

[data-theme="dark"] .header {
    background: rgba(17, 19, 32, 0.88);
}

.header.scrolled {
    box-shadow: var(--shadow-md);
}

.nav-container {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 var(--space-6);
    height: 100%;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.logo {
    display: flex;
    align-items: center;
    gap: var(--space-3);
    color: var(--color-text-primary);
    font-weight: 700;
    font-size: var(--font-size-lg);
    text-decoration: none;
}

.logo:hover { opacity: 0.85; color: var(--color-text-primary); }

.logo-icon {
    width: 36px;
    height: 36px;
    border-radius: var(--radius-lg);
    background: var(--gradient-hero);
    color: white;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 800;
    font-size: var(--font-size-lg);
    box-shadow: 0 2px 10px var(--color-primary-glow);
}

.nav-links {
    display: flex;
    align-items: center;
    gap: var(--space-1);
}

.nav-link {
    padding: var(--space-2) var(--space-4);
    border-radius: var(--radius-md);
    color: var(--color-text-secondary);
    font-weight: 500;
    font-size: var(--font-size-sm);
    transition: all var(--transition-fast);
}

.nav-link:hover {
    color: var(--color-text-primary);
    background: var(--color-surface);
}

.nav-link.active {
    color: var(--color-primary);
    background: var(--color-primary-light);
}

.theme-toggle {
    width: 38px;
    height: 38px;
    border-radius: var(--radius-md);
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--color-text-secondary);
    transition: all var(--transition-fast);
    margin-left: var(--space-2);
}

.theme-toggle:hover {
    color: var(--color-text-primary);
    background: var(--color-surface);
}

.icon-moon { display: none; }
[data-theme="dark"] .icon-sun { display: none; }
[data-theme="dark"] .icon-moon { display: block; }

/* Mobile Menu Toggle */
.mobile-menu-toggle {
    display: none;
    flex-direction: column;
    justify-content: center;
    gap: 5px;
    width: 38px;
    height: 38px;
    padding: 8px;
    border-radius: var(--radius-md);
    transition: background var(--transition-fast);
}

.mobile-menu-toggle:hover { background: var(--color-surface); }

.mobile-menu-toggle span {
    display: block;
    height: 2px;
    background: var(--color-text-primary);
    border-radius: 2px;
    transition: all var(--transition-normal);
}

.mobile-menu-toggle.active span:nth-child(1) { transform: rotate(45deg) translate(5px, 5px); }
.mobile-menu-toggle.active span:nth-child(2) { opacity: 0; }
.mobile-menu-toggle.active span:nth-child(3) { transform: rotate(-45deg) translate(5px, -5px); }

/* Mobile Menu Overlay */
.mobile-menu-overlay {
    display: none;
    position: fixed;
    top: var(--header-height);
    left: 0;
    right: 0;
    bottom: 0;
    z-index: 999;
    background: rgba(0, 0, 0, 0.5);
    backdrop-filter: blur(4px);
    opacity: 0;
    visibility: hidden;
    transition: opacity var(--transition-normal), visibility var(--transition-normal);
}

.mobile-menu-overlay.active { opacity: 1; visibility: visible; }

.mobile-menu {
    background: var(--color-bg-elevated);
    border-bottom: 1px solid var(--color-border);
    padding: var(--space-4) var(--space-6);
    display: flex;
    flex-direction: column;
    gap: var(--space-1);
    box-shadow: var(--shadow-lg);
}

.mobile-nav-link {
    padding: var(--space-3) var(--space-4);
    border-radius: var(--radius-md);
    color: var(--color-text-secondary);
    font-weight: 500;
    font-size: var(--font-size-base);
    transition: all var(--transition-fast);
}

.mobile-nav-link:hover, .mobile-nav-link.active {
    color: var(--color-primary);
    background: var(--color-primary-light);
}

.mobile-theme-toggle {
    width: auto;
    justify-content: flex-start;
    gap: var(--space-3);
    padding: var(--space-3) var(--space-4);
    margin-left: 0;
    font-size: var(--font-size-base);
}

/* ============================================
   Hero + Calculators Section
   ============================================ */
.main-page-wrapper,
.hero-calc-section {
    position: relative;
    padding: calc(var(--header-height) + var(--space-8)) 0 var(--space-12);
    overflow: hidden;
}

.hero-bg-shapes {
    position: absolute;
    inset: 0;
    overflow: hidden;
    pointer-events: none;
}

.shape {
    position: absolute;
    border-radius: 50%;
    filter: blur(100px);
    opacity: 0.10;
    will-change: transform;
    transform: translate3d(0, 0, 0);
    animation: float 25s ease-in-out infinite;
}

[data-theme="dark"] .shape { opacity: 0.06; }

.shape-1 {
    width: 500px;
    height: 500px;
    background: #3a7bd5;
    top: -120px;
    right: -100px;
}

.shape-2 {
    width: 400px;
    height: 400px;
    background: #6c5ce7;
    bottom: -80px;
    left: -80px;
    animation-delay: -8s;
}

.shape-3 {
    width: 300px;
    height: 300px;
    background: #00b4d8;
    top: 40%;
    left: 40%;
    animation-delay: -16s;
}

@keyframes float {
    0%, 100% { transform: translate(0, 0) scale(1); }
    33% { transform: translate(25px, -20px) scale(1.03); }
    66% { transform: translate(-15px, 15px) scale(0.97); }
}

/* 2-Column Main Page Layout (Matches original UI) */
.main-layout-container {
    display: grid;
    grid-template-columns: minmax(0, 1fr) 320px;
    gap: var(--space-8);
    align-items: start;
    position: relative;
    z-index: 1;
}

.main-content-column {
    min-width: 0;
    display: flex;
    flex-direction: column;
    gap: var(--space-6);
}

/* Sidebar Column: Vertical Advertisement */
.sidebar-ad-column {
    width: 320px;
    min-width: 300px;
    flex-shrink: 0;
}

.sidebar-ad-sticky {
    position: sticky;
    top: calc(var(--header-height) + var(--space-5));
    display: flex;
    flex-direction: column;
    gap: var(--space-2);
}

.sidebar-ad-header {
    display: flex;
    justify-content: center;
    align-items: center;
    padding: var(--space-1) 0;
}

.sidebar-ad-header .ad-label {
    letter-spacing: 0.14em;
    font-size: var(--font-size-xs);
    font-weight: 700;
    color: var(--color-text-tertiary);
}

/* Hero Content */
.top-row {
    display: flex;
    align-items: flex-start;
    justify-content: space-between;
    gap: var(--space-6);
    margin-bottom: var(--space-2);
    position: relative;
    z-index: 1;
}

.hero-content {
    flex: 1;
    margin-bottom: var(--space-2);
}

.hero-title {
    font-size: var(--font-size-3xl);
    font-weight: 800;
    letter-spacing: -0.025em;
    margin-bottom: var(--space-2);
    background: var(--gradient-hero);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero-subtitle {
    color: var(--color-text-secondary);
    font-size: var(--font-size-base);
}

/* ============================================
   Calculator Row Bars
   ============================================ */
.calc-rows {
    display: flex;
    flex-direction: column;
    gap: var(--space-4);
    position: relative;
    z-index: 1;
}

.calc-row-bar {
    background: var(--color-bg-elevated);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-xl);
    padding: var(--space-5) var(--space-6);
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: var(--space-4);
    flex-wrap: wrap;
    transition: all var(--transition-normal);
    position: relative;
}

.calc-row-bar::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 2px;
    background: var(--gradient-hero);
    border-radius: var(--radius-xl) var(--radius-xl) 0 0;
    opacity: 0;
    transition: opacity var(--transition-normal);
}

.calc-row-bar:hover {
    border-color: rgba(58, 123, 213, 0.3);
    box-shadow: var(--shadow-md), 0 0 0 1px rgba(58, 123, 213, 0.08);
}

.calc-row-bar:hover::before {
    opacity: 1;
}

.calc-bar-inputs {
    display: flex;
    align-items: center;
    gap: var(--space-3);
    flex-wrap: wrap;
}

.calc-bar-inputs-second {
    width: 100%;
    padding-top: 0;
}

/* Third calculator: two-line layout */
#form-increase-decrease {
    flex-wrap: wrap;
}

#form-increase-decrease .calc-bar-inputs:first-child {
    width: 100%;
}

#form-increase-decrease .calc-bar-actions {
    margin-top: 0;
}

.calc-text {
    color: var(--color-text-secondary);
    font-weight: 500;
    font-size: var(--font-size-sm);
    white-space: nowrap;
    user-select: none;
}

.calc-input {
    width: 100px;
    padding: var(--space-2) var(--space-3);
    border: 2px solid var(--color-border);
    border-radius: var(--radius-md);
    background: var(--color-surface);
    color: var(--color-text-primary);
    font-weight: 600;
    font-size: var(--font-size-base);
    transition: all var(--transition-fast);
    outline: none;
    text-align: center;
}

.calc-input:focus {
    border-color: var(--color-primary);
    box-shadow: 0 0 0 3px var(--color-primary-light);
    background: var(--color-bg-elevated);
}

.calc-input::placeholder {
    color: var(--color-text-tertiary);
    font-weight: 400;
}

/* Remove spinners */
.calc-input::-webkit-outer-spin-button,
.calc-input::-webkit-inner-spin-button { -webkit-appearance: none; margin: 0; }
.calc-input[type=number] { -moz-appearance: textfield; }

.calc-bar-actions {
    display: flex;
    align-items: center;
    gap: var(--space-3);
    margin-left: auto;
}

/* Calculate button */
.btn-calc {
    padding: var(--space-2) var(--space-5);
    border-radius: var(--radius-md);
    font-weight: 700;
    font-size: var(--font-size-sm);
    letter-spacing: 0.03em;
    background: var(--color-primary);
    color: white;
    border: none;
    cursor: pointer;
    transition: all var(--transition-fast);
    white-space: nowrap;
    box-shadow: 0 2px 8px var(--color-primary-glow);
}

.btn-calc:hover {
    background: var(--color-primary-hover);
    box-shadow: 0 4px 16px var(--color-primary-glow);
    transform: translateY(-1px);
}

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

/* Result box */
.result-box {
    min-width: 140px;
    padding: var(--space-2) var(--space-4);
    background: var(--color-surface);
    border: 2px solid var(--color-border);
    border-radius: var(--radius-md);
    font-weight: 700;
    font-size: var(--font-size-base);
    color: var(--color-text-primary);
    text-align: center;
    min-height: 40px;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all var(--transition-fast);
}

.result-box.has-value {
    border-color: var(--color-primary);
    background: var(--color-primary-light);
    color: var(--color-primary);
    animation: resultPop 0.3s ease;
}

@keyframes resultPop {
    0% { transform: scale(0.95); }
    50% { transform: scale(1.04); }
    100% { transform: scale(1); }
}

.result-unit {
    font-weight: 700;
    font-size: var(--font-size-lg);
    color: var(--color-text-secondary);
}

/* Copy button */
.btn-copy {
    width: 38px;
    height: 38px;
    border-radius: var(--radius-md);
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--color-text-tertiary);
    transition: all var(--transition-fast);
    flex-shrink: 0;
    cursor: pointer;
    border: none;
    background: none;
}

.btn-copy:hover {
    color: var(--color-text-primary);
    background: var(--color-surface);
}

.btn-copy.copied {
    color: var(--color-success);
    background: var(--color-success-light);
}

/* ============================================
   Ad Containers
   ============================================ */
.ad-container { margin: var(--space-2) 0; }

.ad-placeholder {
    background: var(--color-surface);
    border: 1px dashed var(--color-border);
    border-radius: var(--radius-xl);
    padding: var(--space-6) var(--space-4);
    display: flex;
    align-items: center;
    justify-content: center;
    min-height: 90px;
    contain: layout style;
    transition: all var(--transition-fast);
}

[data-theme="dark"] .ad-placeholder {
    background: #181b2c;
    border-color: #2e3456;
}

.ad-label {
    font-size: var(--font-size-xs);
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.12em;
    color: var(--color-text-tertiary);
}

.ad-top-right {
    flex-shrink: 0;
    margin: 0;
}

.ad-top-right .ad-placeholder {
    min-width: 200px;
    min-height: 60px;
    padding: var(--space-4);
}

.ad-horizontal-mid {
    margin: var(--space-2) 0;
}

.ad-horizontal-mid .ad-placeholder,
.ad-below-calcs .ad-placeholder {
    min-height: 140px;
}

/* Vertical Skyscraper Ad (Matches UI mockup) */
.ad-vertical-skyscraper {
    min-height: 620px;
    height: auto;
    width: 100%;
    border-radius: var(--radius-xl);
    display: flex;
    align-items: center;
    justify-content: center;
    padding: var(--space-8) var(--space-5);
    background: var(--color-surface);
    border: 1px dashed var(--color-border);
    contain: layout style;
}

[data-theme="dark"] .ad-vertical-skyscraper {
    background: #161929;
    border-color: #2c3254;
}

.ad-content-slot {
    display: flex;
    flex-direction: column;
    align-items: center;
    text-align: center;
    gap: var(--space-3);
}

.ad-icon {
    font-size: 2rem;
    opacity: 0.7;
}

.ad-slot-title {
    font-size: var(--font-size-xs);
    font-weight: 700;
    letter-spacing: 0.14em;
    text-transform: uppercase;
    color: var(--color-text-tertiary);
}

.ad-slot-size {
    font-size: var(--font-size-sm);
    font-weight: 600;
    color: var(--color-text-secondary);
}

.ad-slot-desc {
    font-size: var(--font-size-xs);
    color: var(--color-text-tertiary);
}

/* ============================================
   Related Calculators
   ============================================ */
.related-section {
    padding: var(--space-4) 0 var(--space-2);
}

.section-title-left {
    font-size: var(--font-size-2xl);
    font-weight: 800;
    letter-spacing: -0.02em;
    margin-bottom: var(--space-5);
}

.related-row {
    display: flex;
    gap: var(--space-3);
    flex-wrap: wrap;
}

.related-pill {
    display: flex;
    align-items: center;
    gap: var(--space-3);
    padding: var(--space-3) var(--space-5);
    background: var(--color-bg-elevated);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-xl);
    color: var(--color-text-primary);
    font-weight: 600;
    font-size: var(--font-size-sm);
    transition: all var(--transition-normal);
    text-decoration: none;
}

.related-pill:hover {
    border-color: var(--color-primary);
    box-shadow: var(--shadow-md);
    color: var(--color-primary);
    transform: translateY(-2px);
}

.related-pill svg {
    color: var(--color-text-tertiary);
    transition: all var(--transition-fast);
}

.related-pill:hover svg {
    color: var(--color-primary);
    transform: translateX(3px);
}

.related-pill-icon {
    font-size: 1.1rem;
    line-height: 1;
    display: inline-flex;
    align-items: center;
}

.related-pill-all {
    background: rgba(58, 123, 213, 0.08);
    border-color: var(--color-primary);
    color: var(--color-primary);
    font-weight: 700;
}

[data-theme="dark"] .related-pill-all {
    background: rgba(58, 123, 213, 0.18);
}

.related-pill-all:hover {
    background: var(--color-primary);
    color: #ffffff;
    box-shadow: 0 4px 14px var(--color-primary-glow);
}

.related-pill-all:hover svg {
    color: #ffffff;
}

/* ============================================
   FAQ Section (text-based)
   ============================================ */
.faq-section {
    padding: var(--space-6) 0 var(--space-2);
    border-top: 1px solid var(--color-border-subtle);
}

.faq-block {
    margin-bottom: var(--space-6);
}

.faq-block:last-child {
    margin-bottom: 0;
}

.faq-block h3 {
    font-size: var(--font-size-lg);
    font-weight: 700;
    margin-bottom: var(--space-2);
    color: var(--color-text-primary);
}

.faq-block p {
    color: var(--color-text-secondary);
    line-height: 1.8;
    font-size: var(--font-size-base);
}

/* ============================================
   About Section
   ============================================ */
.about-section {
    padding: var(--space-6) 0 var(--space-4);
    border-top: 1px solid var(--color-border-subtle);
}

.about-text {
    color: var(--color-text-secondary);
    line-height: 1.8;
    font-size: var(--font-size-base);
}

/* ============================================
   Footer
   ============================================ */
.footer {
    border-top: 1px solid var(--color-border);
    padding: var(--space-6) 0;
    background: var(--color-bg-alt);
    content-visibility: auto;
    contain-intrinsic-size: 0 80px;
}

.footer-row {
    display: flex;
    align-items: center;
    justify-content: space-between;
    flex-wrap: wrap;
    gap: var(--space-4);
}

.footer-copyright {
    font-size: var(--font-size-sm);
    color: var(--color-text-tertiary);
}

.footer-links {
    display: flex;
    gap: var(--space-5);
}

.footer-links a {
    font-size: var(--font-size-sm);
    color: var(--color-text-secondary);
    transition: color var(--transition-fast);
}

.footer-links a:hover {
    color: var(--color-primary);
}

/* ============================================
   Cookie Banner
   ============================================ */
.cookie-banner {
    position: fixed;
    bottom: 0;
    left: 0;
    right: 0;
    z-index: 10000;
    background: var(--color-bg-elevated);
    border-top: 1px solid var(--color-border);
    box-shadow: 0 -4px 24px rgba(0,0,0,0.1);
    padding: var(--space-5) var(--space-6);
    transform: translateY(100%);
    transition: transform var(--transition-slow);
}

.cookie-banner.visible { transform: translateY(0); }

[data-theme="dark"] .cookie-banner { box-shadow: 0 -4px 24px rgba(0,0,0,0.3); }

.cookie-content {
    max-width: var(--max-width);
    margin: 0 auto;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: var(--space-6);
}

.cookie-text {
    display: flex;
    align-items: flex-start;
    gap: var(--space-3);
    flex: 1;
}

.cookie-text svg {
    flex-shrink: 0;
    margin-top: 2px;
    color: #f59e0b;
}

.cookie-text p {
    font-size: var(--font-size-sm);
    color: var(--color-text-secondary);
    line-height: 1.6;
}

.cookie-text a { font-weight: 600; }

.cookie-actions {
    display: flex;
    gap: var(--space-3);
    flex-shrink: 0;
}

.btn-cookie-decline {
    padding: var(--space-2) var(--space-5);
    border-radius: var(--radius-md);
    font-weight: 600;
    font-size: var(--font-size-sm);
    color: var(--color-text-secondary);
    background: var(--color-surface);
    border: 1px solid var(--color-border);
    cursor: pointer;
    transition: all var(--transition-fast);
}

.btn-cookie-decline:hover {
    background: var(--color-surface-hover);
    color: var(--color-text-primary);
}

.btn-cookie-accept {
    padding: var(--space-2) var(--space-5);
    border-radius: var(--radius-md);
    font-weight: 600;
    font-size: var(--font-size-sm);
    color: white;
    background: var(--color-primary);
    border: none;
    cursor: pointer;
    transition: all var(--transition-fast);
}

.btn-cookie-accept:hover { background: var(--color-primary-hover); }

/* ============================================
   Toast
   ============================================ */
.toast {
    position: fixed;
    bottom: var(--space-8);
    left: 50%;
    transform: translateX(-50%) translateY(80px);
    z-index: 10001;
    display: flex;
    align-items: center;
    gap: var(--space-2);
    padding: var(--space-3) var(--space-5);
    background: var(--color-bg-elevated);
    border: 1px solid var(--color-success);
    border-radius: var(--radius-full);
    box-shadow: var(--shadow-lg);
    font-size: var(--font-size-sm);
    font-weight: 600;
    color: var(--color-success);
    opacity: 0;
    visibility: hidden;
    transition: all var(--transition-normal);
}

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

/* ============================================
   Sub-Page Specific Styles
   ============================================ */

/* Calculator Page Hero */
.page-hero {
    padding: calc(var(--header-height) + var(--space-10)) 0 var(--space-6);
    position: relative;
    overflow: hidden;
}

.page-hero .hero-bg-shapes {
    position: absolute;
    inset: 0;
    overflow: hidden;
    pointer-events: none;
}

.page-title {
    font-size: var(--font-size-3xl);
    font-weight: 800;
    letter-spacing: -0.025em;
    margin-bottom: var(--space-2);
    background: var(--gradient-hero);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    position: relative;
    z-index: 1;
}

.page-subtitle {
    color: var(--color-text-secondary);
    font-size: var(--font-size-base);
    position: relative;
    z-index: 1;
    margin-bottom: var(--space-6);
}

/* Sub-page calc cards (for individual calculator pages) */
.calc-page-card {
    background: var(--color-bg-elevated);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-2xl);
    padding: var(--space-8);
    margin-bottom: var(--space-6);
    transition: all var(--transition-normal);
    position: relative;
    overflow: hidden;
}

.calc-page-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 3px;
    background: var(--gradient-hero);
}

.calc-page-card:hover {
    box-shadow: var(--shadow-lg);
}

.calc-page-form {
    display: flex;
    flex-direction: column;
    gap: var(--space-5);
}

.calc-page-row {
    display: flex;
    align-items: center;
    gap: var(--space-3);
    flex-wrap: wrap;
}

.calc-page-label {
    color: var(--color-text-secondary);
    font-weight: 600;
    font-size: var(--font-size-sm);
    min-width: 120px;
}

.calc-page-input {
    width: 180px;
    padding: var(--space-3) var(--space-4);
    border: 2px solid var(--color-border);
    border-radius: var(--radius-lg);
    background: var(--color-surface);
    color: var(--color-text-primary);
    font-weight: 600;
    font-size: var(--font-size-lg);
    transition: all var(--transition-fast);
    outline: none;
}

.calc-page-input:focus {
    border-color: var(--color-primary);
    box-shadow: 0 0 0 3px var(--color-primary-light);
    background: var(--color-bg-elevated);
}

.calc-page-input::placeholder {
    color: var(--color-text-tertiary);
    font-weight: 400;
}

.calc-page-input::-webkit-outer-spin-button,
.calc-page-input::-webkit-inner-spin-button { -webkit-appearance: none; margin: 0; }
.calc-page-input[type=number] { -moz-appearance: textfield; }

.calc-page-actions {
    display: flex;
    align-items: center;
    gap: var(--space-4);
    flex-wrap: wrap;
    padding-top: var(--space-2);
}

.btn-page-calc {
    padding: var(--space-3) var(--space-8);
    border-radius: var(--radius-lg);
    font-weight: 700;
    font-size: var(--font-size-base);
    letter-spacing: 0.03em;
    background: var(--color-primary);
    color: white;
    border: none;
    cursor: pointer;
    transition: all var(--transition-fast);
    box-shadow: 0 2px 8px var(--color-primary-glow);
}

.btn-page-calc:hover {
    background: var(--color-primary-hover);
    box-shadow: 0 4px 16px var(--color-primary-glow);
    transform: translateY(-1px);
}

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

.result-page-group {
    display: flex;
    align-items: center;
    gap: var(--space-3);
}

.result-page-box {
    min-width: 180px;
    padding: var(--space-3) var(--space-5);
    background: var(--color-surface);
    border: 2px solid var(--color-border);
    border-radius: var(--radius-lg);
    font-weight: 700;
    font-size: var(--font-size-xl);
    color: var(--color-text-primary);
    text-align: center;
    min-height: 48px;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all var(--transition-fast);
}

.result-page-box.has-value {
    border-color: var(--color-primary);
    background: var(--color-primary-light);
    color: var(--color-primary);
    animation: resultPop 0.3s ease;
}

.result-page-label {
    font-size: var(--font-size-sm);
    font-weight: 600;
    color: var(--color-text-tertiary);
}

/* Result breakdown (multiple results) */
.result-breakdown {
    display: flex;
    flex-direction: column;
    gap: var(--space-3);
    padding-top: var(--space-4);
    border-top: 1px solid var(--color-border-subtle);
    margin-top: var(--space-4);
}

.result-breakdown-item {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: var(--space-3) var(--space-4);
    background: var(--color-surface);
    border-radius: var(--radius-md);
}

.result-breakdown-label {
    font-size: var(--font-size-sm);
    font-weight: 600;
    color: var(--color-text-secondary);
}

.result-breakdown-value {
    font-size: var(--font-size-lg);
    font-weight: 700;
    color: var(--color-text-primary);
}

.result-breakdown-value.has-value {
    color: var(--color-primary);
    animation: resultPop 0.3s ease;
}

/* "Back to home" link on sub-pages */
.breadcrumb {
    padding: calc(var(--header-height) + var(--space-4)) 0 0;
    font-size: var(--font-size-sm);
    position: relative;
    z-index: 1;
}

.breadcrumb a {
    color: var(--color-text-tertiary);
    font-weight: 500;
    transition: color var(--transition-fast);
}

.breadcrumb a:hover { color: var(--color-primary); }
.breadcrumb span { color: var(--color-text-tertiary); margin: 0 var(--space-2); }

/* ============================================
   Directory Hub (more-calculators.html)
   ============================================ */
.dir-search-bar {
    position: relative;
    margin-bottom: var(--space-5);
    max-width: 540px;
}

.dir-search-input {
    width: 100%;
    padding: var(--space-3) var(--space-4) var(--space-3) 44px;
    border: 2px solid var(--color-border);
    border-radius: var(--radius-xl);
    background: var(--color-bg-elevated);
    color: var(--color-text-primary);
    font-size: var(--font-size-base);
    font-family: inherit;
    outline: none;
    transition: all var(--transition-fast);
}

.dir-search-input:focus {
    border-color: var(--color-primary);
    box-shadow: 0 0 0 3px var(--color-primary-light);
}

.dir-search-icon {
    position: absolute;
    left: 14px;
    top: 50%;
    transform: translateY(-50%);
    color: var(--color-text-tertiary);
    pointer-events: none;
}

.category-filter-pills {
    display: flex;
    gap: var(--space-2);
    flex-wrap: wrap;
    margin-bottom: var(--space-6);
}

.cat-pill {
    padding: var(--space-2) var(--space-4);
    border-radius: var(--radius-full);
    border: 1px solid var(--color-border);
    background: var(--color-bg-elevated);
    color: var(--color-text-secondary);
    font-size: var(--font-size-sm);
    font-weight: 600;
    cursor: pointer;
    transition: all var(--transition-fast);
}

.cat-pill:hover {
    border-color: var(--color-primary);
    color: var(--color-primary);
    background: var(--color-surface);
}

.cat-pill.active {
    background: var(--color-primary);
    color: white;
    border-color: var(--color-primary);
    box-shadow: 0 2px 8px var(--color-primary-glow);
}

.calc-dir-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: var(--space-4);
    margin-bottom: var(--space-8);
}

.calc-dir-card {
    background: var(--color-bg-elevated);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-xl);
    padding: var(--space-5);
    display: flex;
    flex-direction: column;
    justify-content: space-between;
    transition: all var(--transition-normal);
    text-decoration: none;
    position: relative;
    overflow: hidden;
}

.calc-dir-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 3px;
    background: var(--gradient-hero);
    opacity: 0;
    transition: opacity var(--transition-normal);
}

.calc-dir-card:hover {
    transform: translateY(-3px);
    border-color: var(--color-primary);
    box-shadow: var(--shadow-lg);
}

.calc-dir-card:hover::before {
    opacity: 1;
}

.calc-dir-top {
    display: flex;
    align-items: flex-start;
    justify-content: space-between;
    gap: var(--space-3);
    margin-bottom: var(--space-3);
}

.calc-dir-icon {
    width: 44px;
    height: 44px;
    border-radius: var(--radius-lg);
    background: var(--color-surface);
    color: var(--color-primary);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.35rem;
    flex-shrink: 0;
}

.calc-dir-badge {
    font-size: var(--font-size-xs);
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.08em;
    padding: var(--space-1) var(--space-2);
    border-radius: var(--radius-md);
    background: var(--color-surface);
    color: var(--color-text-secondary);
}

.calc-dir-title {
    font-size: var(--font-size-lg);
    font-weight: 700;
    color: var(--color-text-primary);
    margin-bottom: var(--space-2);
}

.calc-dir-desc {
    font-size: var(--font-size-sm);
    color: var(--color-text-secondary);
    line-height: 1.6;
    margin-bottom: var(--space-4);
    flex: 1;
}

.calc-dir-footer {
    display: flex;
    align-items: center;
    justify-content: space-between;
    font-size: var(--font-size-sm);
    font-weight: 600;
    color: var(--color-primary);
    padding-top: var(--space-3);
    border-top: 1px solid var(--color-border-subtle);
}

.calc-dir-footer svg {
    transition: transform var(--transition-fast);
}

.calc-dir-card:hover .calc-dir-footer svg {
    transform: translateX(4px);
}

/* ============================================
   Presets & Select Inputs for Advanced Calculators
   ============================================ */
.preset-btn-group {
    display: flex;
    gap: var(--space-2);
    flex-wrap: wrap;
    margin-top: var(--space-1);
}

.preset-btn {
    padding: var(--space-2) var(--space-3);
    border-radius: var(--radius-md);
    border: 1px solid var(--color-border);
    background: var(--color-surface);
    color: var(--color-text-secondary);
    font-weight: 600;
    font-size: var(--font-size-sm);
    cursor: pointer;
    transition: all var(--transition-fast);
}

.preset-btn:hover {
    border-color: var(--color-primary);
    color: var(--color-primary);
}

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

.calc-page-select {
    width: 180px;
    padding: var(--space-3) var(--space-4);
    border: 2px solid var(--color-border);
    border-radius: var(--radius-lg);
    background: var(--color-surface);
    color: var(--color-text-primary);
    font-weight: 600;
    font-size: var(--font-size-base);
    transition: all var(--transition-fast);
    outline: none;
    cursor: pointer;
}

.calc-page-select:focus {
    border-color: var(--color-primary);
    box-shadow: 0 0 0 3px var(--color-primary-light);
}

/* Formula Box */
.formula-box {
    background: var(--color-surface);
    border-left: 4px solid var(--color-primary);
    border-radius: 0 var(--radius-md) var(--radius-md) 0;
    padding: var(--space-3) var(--space-4);
    margin: var(--space-3) 0;
    font-family: monospace;
    font-size: var(--font-size-sm);
    color: var(--color-text-primary);
}

/* ============================================
   Responsive
   ============================================ */
@media (max-width: 1040px) {
    .main-layout-container {
        grid-template-columns: minmax(0, 1fr) 280px;
        gap: var(--space-6);
    }

    .sidebar-ad-column {
        width: 280px;
        min-width: 260px;
    }
}

@media (max-width: 920px) {
    .main-layout-container {
        grid-template-columns: 1fr;
        gap: var(--space-6);
    }

    .sidebar-ad-column {
        width: 100%;
        min-width: auto;
        max-width: 100%;
        margin: var(--space-4) 0 0;
    }

    .sidebar-ad-sticky {
        position: static;
    }

    .ad-vertical-skyscraper {
        min-height: 250px;
        max-height: 320px;
        padding: var(--space-5);
    }
}

@media (max-width: 768px) {
    :root {
        --font-size-3xl: 1.6rem;
        --font-size-2xl: 1.3rem;
    }

    .nav-links { display: none; }
    .mobile-menu-toggle { display: flex; }
    .mobile-menu-overlay { display: block; }

    .main-page-wrapper,
    .hero-calc-section {
        padding-top: calc(var(--header-height) + var(--space-5));
        padding-bottom: var(--space-8);
    }

    .top-row {
        flex-direction: column;
        gap: var(--space-4);
    }

    .ad-top-right {
        width: 100%;
    }

    .ad-top-right .ad-placeholder {
        min-width: auto;
    }

    .calc-row-bar {
        flex-direction: column;
        align-items: stretch;
        padding: var(--space-4);
        gap: var(--space-3);
    }

    .calc-bar-inputs {
        display: flex;
        align-items: center;
        flex-wrap: wrap;
        gap: var(--space-2);
        width: 100%;
    }

    .calc-text {
        font-size: var(--font-size-sm);
        white-space: normal;
    }

    .calc-input {
        width: 85px;
        flex: 1 1 70px;
        min-width: 65px;
        height: 42px;
        font-size: 16px; /* Prevents auto-zoom on iOS */
    }

    .calc-bar-actions {
        display: flex;
        align-items: center;
        gap: var(--space-2);
        width: 100%;
        margin-left: 0;
    }

    .btn-calc {
        flex: 0 0 auto;
        height: 42px;
        padding: 0 var(--space-4);
    }

    .result-box {
        min-width: 0;
        flex: 1 1 auto;
        height: 42px;
        font-size: var(--font-size-base);
    }

    .btn-copy {
        width: 42px;
        height: 42px;
        flex: 0 0 42px;
    }

    .related-row {
        flex-direction: column;
    }

    .related-pill {
        width: 100%;
        justify-content: space-between;
    }

    .footer-row {
        flex-direction: column;
        text-align: center;
    }

    .cookie-content {
        flex-direction: column;
        text-align: center;
    }

    .cookie-text {
        flex-direction: column;
        align-items: center;
    }

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

    /* Sub-page responsive */
    .calc-page-card { padding: var(--space-5); }
    .calc-page-row { flex-direction: column; align-items: stretch; }
    .calc-page-label { min-width: auto; }
    .calc-page-input { width: 100%; font-size: 16px; }
    .calc-page-actions { flex-direction: column; align-items: stretch; }
    .result-page-box { min-width: auto; width: 100%; }
    .result-page-group { flex-direction: column; align-items: stretch; }
}

@media (max-width: 480px) {
    :root {
        --font-size-3xl: 1.35rem;
        --font-size-2xl: 1.15rem;
    }

    .container {
        padding: 0 var(--space-4);
    }

    .logo-text {
        font-size: var(--font-size-sm);
    }

    .calc-row-bar {
        padding: var(--space-3) var(--space-3);
    }

    .calc-bar-inputs {
        gap: 6px;
    }

    .calc-input {
        min-width: 58px;
        padding: var(--space-1) var(--space-2);
        font-size: 16px;
    }

    .calc-text {
        font-size: var(--font-size-xs);
    }

    .btn-calc {
        font-size: var(--font-size-xs);
        padding: 0 var(--space-3);
    }

    .result-box {
        font-size: var(--font-size-sm);
        padding: var(--space-1) var(--space-2);
    }

    .btn-copy {
        width: 38px;
        height: 38px;
    }
}

/* ============================================
   Print Styles
   ============================================ */
@media print {
    .ad-container, .cookie-banner, .header, .toast { display: none !important; }
    body { background: white; color: black; }
    .calc-row-bar { box-shadow: none; border: 1px solid #ddd; break-inside: avoid; }
}

/* ============================================
   Accessibility
   ============================================ */
@media (prefers-reduced-motion: reduce) {
    *, *::before, *::after {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
    }
    html { scroll-behavior: auto; }
}

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