/* ============================================================
   Theme tokens
   ============================================================ */
:root {
    --font-serif: "Fraunces", "Iowan Old Style", "Apple Garamond", Georgia, serif;
    --font-sans: "Inter", -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;

    --max-width: 720px;
    --header-height: 64px;

    --transition-fast: 180ms ease;
    --transition-medium: 320ms ease;

    --radius-sm: 6px;
    --radius-md: 12px;
    --radius-lg: 16px;
}

[data-theme="light"] {
    --color-bg: #fafaf7;
    --color-surface: #f3f1ec;
    --color-text: #1a1a1a;
    --color-text-muted: #5a5a5a;
    --color-border: #e3e0d8;
    --color-accent: #1a1a1a;
    --color-link: #1a1a1a;
    --color-link-hover: #5a5a5a;
}

[data-theme="dark"] {
    --color-bg: #131312;
    --color-surface: #1c1c1a;
    --color-text: #ececea;
    --color-text-muted: #9a9a96;
    --color-border: #2a2a27;
    --color-accent: #ececea;
    --color-link: #ececea;
    --color-link-hover: #b8b8b3;
}

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

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

body {
    font-family: var(--font-sans);
    font-size: 16px;
    line-height: 1.65;
    color: var(--color-text);
    background-color: var(--color-bg);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    transition: background-color var(--transition-medium), color var(--transition-medium);
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

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

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

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

ul {
    list-style: none;
}

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

/* ============================================================
   Header
   ============================================================ */
.site-header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 100;
    height: var(--header-height);
    background-color: color-mix(in srgb, var(--color-bg) 88%, transparent);
    backdrop-filter: saturate(180%) blur(12px);
    -webkit-backdrop-filter: saturate(180%) blur(12px);
    border-bottom: 1px solid var(--color-border);
    transition: background-color var(--transition-medium), border-color var(--transition-medium);
}

.header-inner {
    height: 100%;
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 1.25rem;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 1rem;
}

.site-logo {
    font-family: var(--font-serif);
    font-size: 1.25rem;
    font-weight: 600;
    letter-spacing: -0.01em;
    color: var(--color-text);
}

.site-logo:hover {
    color: var(--color-text-muted);
}

.site-nav {
    display: none;
    margin-left: auto;
}

.nav-list {
    display: flex;
    gap: 1.75rem;
}

.nav-link {
    font-size: 0.9rem;
    font-weight: 500;
    color: var(--color-text-muted);
    position: relative;
}

.nav-link::after {
    content: "";
    position: absolute;
    left: 0;
    right: 0;
    bottom: -4px;
    height: 1px;
    background-color: currentColor;
    transform: scaleX(0);
    transform-origin: left;
    transition: transform var(--transition-fast);
}

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

.nav-link:hover::after {
    transform: scaleX(1);
}

/* Active nav state — no href, distinct color/weight, no underline animation */
.nav-link.is-active,
.mobile-nav-link.is-active {
    color: var(--color-text);
    font-weight: 600;
    cursor: default;
}

.nav-link.is-active::after {
    display: none;
}

.nav-link.is-active:hover {
    color: var(--color-text);
}

.header-actions {
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.lang-flag {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 0.25rem;
    border-radius: var(--radius-sm);
    transition: background-color var(--transition-fast);
}

.lang-flag:hover {
    background-color: var(--color-surface);
}

.lang-flag svg {
    display: block;
    width: 24px;
    height: 16px;
    border-radius: 2px;
    box-shadow: 0 0 0 1px color-mix(in srgb, var(--color-border) 70%, transparent);
}

.theme-toggle {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 36px;
    height: 36px;
    border-radius: var(--radius-sm);
    color: var(--color-text-muted);
    transition: color var(--transition-fast), background-color var(--transition-fast);
}

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

.icon-sun,
.icon-moon {
    display: none;
}

[data-theme="light"] .icon-moon {
    display: block;
}

[data-theme="dark"] .icon-sun {
    display: block;
}

.menu-toggle {
    display: flex;
    flex-direction: column;
    justify-content: center;
    gap: 4px;
    width: 36px;
    height: 36px;
    padding: 8px;
    border-radius: var(--radius-sm);
    transition: background-color var(--transition-fast);
}

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

.menu-toggle span {
    display: block;
    height: 1.5px;
    width: 100%;
    background-color: var(--color-text);
    border-radius: 1px;
    transition: transform var(--transition-fast), opacity var(--transition-fast);
}

.menu-toggle[aria-expanded="true"] span:nth-child(1) {
    transform: translateY(5.5px) rotate(45deg);
}

.menu-toggle[aria-expanded="true"] span:nth-child(2) {
    opacity: 0;
}

.menu-toggle[aria-expanded="true"] span:nth-child(3) {
    transform: translateY(-5.5px) rotate(-45deg);
}

/* Mobile nav */
.mobile-nav {
    border-top: 1px solid var(--color-border);
    background-color: var(--color-bg);
    padding: 1rem 1.25rem 1.5rem;
}

.mobile-nav[hidden] {
    display: none;
}

.mobile-nav-list {
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
}

.mobile-nav-link {
    display: block;
    padding: 0.5rem 0;
    font-size: 1rem;
    color: var(--color-text);
    border-bottom: 1px solid var(--color-border);
}

/* ============================================================
   Main content
   ============================================================ */
.main-content {
    flex: 1;
    max-width: var(--max-width);
    width: 100%;
    margin: 0 auto;
    padding: calc(var(--header-height) + 3rem) 1.25rem 4rem;
}

/* Section reveal animation */
.reveal {
    opacity: 0;
    transform: translateY(24px);
    transition: opacity 700ms ease, transform 700ms ease;
}

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

@media (prefers-reduced-motion: reduce) {
    .reveal {
        opacity: 1;
        transform: none;
        transition: none;
    }
}

/* ============================================================
   Hero
   ============================================================ */
.hero {
    padding: 3rem 0 4rem;
    border-bottom: 1px solid var(--color-border);
}

.hero-title {
    font-family: var(--font-serif);
    font-size: clamp(2.75rem, 8vw, 4.5rem);
    font-weight: 600;
    letter-spacing: -0.025em;
    line-height: 1.05;
    margin-bottom: 1.5rem;
}

.hero-subtitle {
    font-size: 1.05rem;
    line-height: 1.7;
    color: var(--color-text-muted);
    max-width: 36rem;
}

:lang(en) .hero-subtitle {
    max-width: 42rem;
}

/* ============================================================
   App sections (category + card grid) — reusable template
   ============================================================ */
.app-section {
    padding: 3rem 0;
    border-bottom: 1px solid var(--color-border);
}

.app-section:last-of-type {
    border-bottom: none;
}

.app-section-title {
    font-family: var(--font-serif);
    font-size: 1.35rem;
    font-weight: 600;
    letter-spacing: -0.015em;
    color: var(--color-text);
    margin-bottom: 1.5rem;
}

.app-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: 1.25rem;
}

.app-card {
    background-color: var(--color-surface);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-md);
    padding: 1.5rem;
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
    min-height: 180px;
    transition: background-color var(--transition-medium), border-color var(--transition-medium), opacity var(--transition-medium);
}

.app-card.is-disabled {
    opacity: 0.6;
    cursor: not-allowed;
}

.app-card-emoji {
    font-size: 1.75rem;
    line-height: 1;
}

.app-card-title {
    font-family: var(--font-serif);
    font-size: 1.15rem;
    font-weight: 600;
    letter-spacing: -0.01em;
    color: var(--color-text);
}

.app-card-text {
    font-size: 0.95rem;
    color: var(--color-text-muted);
    line-height: 1.6;
    flex: 1;
}

.app-card-cta {
    font-size: 0.75rem;
    color: var(--color-text-muted);
    font-weight: 500;
    letter-spacing: 0.08em;
    text-transform: uppercase;
    margin-top: auto;
}

/* Empty placeholder card — disabled shell, no content */
.app-card--placeholder {
    opacity: 0.45;
    align-items: center;
    justify-content: center;
    min-height: 140px;
}

.app-card-placeholder-mark {
    color: var(--color-text-muted);
    font-size: 1.25rem;
    letter-spacing: 0.2em;
    line-height: 1;
}

/* ============================================================
   Footer
   ============================================================ */
.site-footer {
    border-top: 1px solid var(--color-border);
    padding: 2rem 1.25rem;
    margin-top: 2rem;
    transition: border-color var(--transition-medium);
}

.footer-inner {
    max-width: var(--max-width);
    margin: 0 auto;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 1rem;
}

.footer-copy {
    font-size: 0.85rem;
    color: var(--color-text-muted);
}

.footer-social {
    display: flex;
    gap: 1rem;
}

.footer-social-link {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    color: var(--color-text-muted);
    padding: 0.4rem;
    transition: color var(--transition-fast), opacity var(--transition-fast), transform var(--transition-fast);
}

.footer-social-link:hover {
    color: var(--color-text);
    opacity: 0.75;
    transform: translateY(-2px);
}

.footer-social-link svg {
    width: 24px;
    height: 24px;
    flex-shrink: 0;
    pointer-events: none;
}

/* ============================================================
   Responsive: tablet & up
   ============================================================ */
@media (min-width: 720px) {
    .header-inner {
        padding: 0 2rem;
    }

    .site-nav {
        display: block;
    }

    .menu-toggle {
        display: none;
    }

    .mobile-nav {
        display: none !important;
    }

    .main-content {
        padding-left: 2rem;
        padding-right: 2rem;
    }

    .site-footer {
        padding-left: 2rem;
        padding-right: 2rem;
    }

    .app-grid {
        grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
    }
}