/* ===============================================
   AIRMI - AI Risk Management Institute
   Design System v2.0 — Premium Institutional
   =============================================== */

/* ===== CSS Custom Properties ===== */
:root {
    --navy-900: #0D1B2A;
    --navy-800: #1B2D45;
    --navy-700: #1B3A5C;
    --navy-600: #2E5077;
    --navy-500: #4A7A9B;
    --navy-400: #6B9DC2;
    --gold-600: #9A7B2F;
    --gold-500: #C4930A;
    --gold-400: #D4A83A;
    --gold-300: #E8C96A;
    --gold-200: #F2DFA0;
    --warm-50: #FAFAF8;
    --warm-100: #F5F4F2;
    --warm-200: #E8E6E3;
    --warm-300: #D1CEC9;
    --warm-400: #A8A29E;
    --warm-500: #78716C;
    --text-primary: #1A1A1A;
    --text-secondary: #4A5568;
    --text-tertiary: #718096;

    --font-heading: 'Noto Serif JP', 'Yu Mincho', serif;
    --font-body: 'Noto Sans JP', 'Hiragino Kaku Gothic ProN', sans-serif;
    --font-en: 'Inter', -apple-system, sans-serif;
}

/* ===== Base Styles ===== */
@media (prefers-reduced-motion: no-preference) {
    html {
        scroll-behavior: smooth;
    }
}

body {
    font-family: var(--font-body);
    font-feature-settings: "palt" 1;
    letter-spacing: 0.02em;
    line-height: 1.8;
    overflow-x: hidden;
    color: var(--text-primary);
    background-color: #fff;
}

h1, h2, h3, h4, h5, h6 {
    font-family: var(--font-heading);
    letter-spacing: 0.04em;
    line-height: 1.3;
}

/* ===== Signature Element: Hex Pattern ===== */
.hex-pattern {
    background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='56' height='100' viewBox='0 0 56 100'%3E%3Cpath d='M28 66L0 50L0 16L28 0L56 16L56 50L28 66L28 100' fill='none' stroke='%23C4930A' stroke-width='0.5'/%3E%3Cpath d='M28 0L28 34L0 50L0 84L28 100L56 84L56 50L28 34' fill='none' stroke='%23C4930A' stroke-width='0.5'/%3E%3C/svg%3E");
    background-size: 56px 100px;
}

/* ===== Section Divider ===== */
.section-divider {
    width: 64px;
    height: 3px;
    background: linear-gradient(90deg, var(--gold-500), var(--gold-300));
    border-radius: 2px;
}

/* ===== EN Label ===== */
.en-label {
    font-family: var(--font-en);
    font-size: 0.75rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.2em;
    color: var(--gold-500);
}

/* ===== Header Styles ===== */
#header {
    transition: background-color 0.4s ease, box-shadow 0.4s ease, padding 0.3s ease;
}

#header.scrolled {
    background-color: var(--navy-900) !important;
    box-shadow: 0 2px 8px -1px rgba(13, 27, 42, 0.15);
    padding-top: 0.5rem;
    padding-bottom: 0.5rem;
}

#header.scrolled .nav-link {
    color: var(--warm-200) !important;
}

#header.scrolled .nav-link:hover {
    color: var(--gold-400) !important;
}

#header.scrolled .nav-cta {
    background-color: var(--gold-500) !important;
    color: var(--navy-900) !important;
}

/* Nav link hover underline */
.nav-link {
    position: relative;
    transition: color 0.3s ease;
}

.nav-link::after {
    content: '';
    position: absolute;
    bottom: -4px;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--gold-500);
    transition: width 0.3s ease;
}

.nav-link:hover::after {
    width: 100%;
}

/* Mobile Menu */
#mobile-menu {
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.4s cubic-bezier(0.4, 0, 0.2, 1);
}

#mobile-menu.show {
    max-height: 500px;
}

/* ===== Card Styles ===== */
.card {
    background: #fff;
    border-radius: 4px;
    box-shadow: 0 2px 12px -2px rgba(13, 27, 42, 0.08);
    transition: transform 0.35s cubic-bezier(0.4, 0, 0.2, 1), box-shadow 0.35s ease;
}

.card:hover {
    transform: translateY(-6px);
    box-shadow: 0 12px 32px -4px rgba(13, 27, 42, 0.12);
}

.card--bordered {
    border-top: 3px solid var(--navy-700);
}

.card--gold-bordered {
    border-top: 3px solid var(--gold-500);
}

.card--dark {
    background: rgba(255, 255, 255, 0.04);
    border: 1px solid rgba(255, 255, 255, 0.08);
    -webkit-backdrop-filter: blur(8px);
    backdrop-filter: blur(8px);
}

/* Service card */
.service-card {
    transition: transform 0.3s ease, border-color 0.3s ease;
    border-left: 3px solid transparent;
}

.service-card:hover {
    border-left-color: var(--gold-500);
    transform: translateX(4px);
}

/* ===== Button Styles ===== */
.btn-primary {
    background-color: var(--gold-500);
    color: var(--navy-900);
    font-weight: 700;
    transition: background-color 0.3s ease, transform 0.3s ease, box-shadow 0.3s ease;
    border-radius: 4px;
}

.btn-primary:hover {
    background-color: var(--gold-400);
    transform: translateY(-2px);
    box-shadow: 0 8px 20px -4px rgba(196, 147, 10, 0.3);
}

.btn-secondary {
    background: transparent;
    color: var(--warm-200);
    border: 1px solid rgba(255, 255, 255, 0.2);
    font-weight: 700;
    transition: background-color 0.3s ease, border-color 0.3s ease;
    border-radius: 4px;
}

.btn-secondary:hover {
    background: rgba(255, 255, 255, 0.05);
    border-color: rgba(255, 255, 255, 0.4);
}

.btn-dark {
    background-color: var(--navy-700);
    color: #fff;
    font-weight: 700;
    transition: background-color 0.3s ease, transform 0.3s ease, box-shadow 0.3s ease;
    border-radius: 4px;
}

.btn-dark:hover {
    background-color: var(--navy-800);
    transform: translateY(-2px);
    box-shadow: 0 8px 20px -4px rgba(27, 58, 92, 0.3);
}

/* ===== Animation: 8 Unique Reveal Types ===== */

/* 1: Slide up */
[data-reveal="up"] {
    opacity: 0;
    transform: translateY(40px);
    transition: opacity 0.7s cubic-bezier(0.4, 0, 0.2, 1), transform 0.7s cubic-bezier(0.4, 0, 0.2, 1);
}
[data-reveal="up"].revealed {
    opacity: 1;
    transform: translateY(0);
}

/* 2: Slide from left */
[data-reveal="left"] {
    opacity: 0;
    transform: translateX(-50px);
    transition: opacity 0.7s cubic-bezier(0.4, 0, 0.2, 1), transform 0.7s cubic-bezier(0.4, 0, 0.2, 1);
}
[data-reveal="left"].revealed {
    opacity: 1;
    transform: translateX(0);
}

/* 3: Slide from right */
[data-reveal="right"] {
    opacity: 0;
    transform: translateX(50px);
    transition: opacity 0.7s cubic-bezier(0.4, 0, 0.2, 1), transform 0.7s cubic-bezier(0.4, 0, 0.2, 1);
}
[data-reveal="right"].revealed {
    opacity: 1;
    transform: translateX(0);
}

/* 4: Scale in */
[data-reveal="scale"] {
    opacity: 0;
    transform: scale(0.9);
    transition: opacity 0.6s cubic-bezier(0.4, 0, 0.2, 1), transform 0.6s cubic-bezier(0.4, 0, 0.2, 1);
}
[data-reveal="scale"].revealed {
    opacity: 1;
    transform: scale(1);
}

/* 5: Fade + unblur */
[data-reveal="unblur"] {
    opacity: 0;
    filter: blur(8px);
    transition: opacity 0.8s ease, filter 0.8s ease;
}
[data-reveal="unblur"].revealed {
    opacity: 1;
    filter: blur(0);
}

/* 6: Clip reveal */
[data-reveal="clip"] {
    clip-path: inset(0 0 100% 0);
    transition: clip-path 0.8s cubic-bezier(0.4, 0, 0.2, 1);
}
[data-reveal="clip"].revealed {
    clip-path: inset(0 0 0 0);
}

/* 7: Stagger children */
[data-reveal="stagger"] > * {
    opacity: 0;
    transform: translateY(30px);
    transition: opacity 0.5s cubic-bezier(0.4, 0, 0.2, 1), transform 0.5s cubic-bezier(0.4, 0, 0.2, 1);
}
[data-reveal="stagger"].revealed > *:nth-child(1) { transition-delay: 0s; }
[data-reveal="stagger"].revealed > *:nth-child(2) { transition-delay: 0.06s; }
[data-reveal="stagger"].revealed > *:nth-child(3) { transition-delay: 0.12s; }
[data-reveal="stagger"].revealed > *:nth-child(4) { transition-delay: 0.18s; }
[data-reveal="stagger"].revealed > *:nth-child(5) { transition-delay: 0.24s; }
[data-reveal="stagger"].revealed > *:nth-child(6) { transition-delay: 0.3s; }
[data-reveal="stagger"].revealed > *:nth-child(7) { transition-delay: 0.36s; }
[data-reveal="stagger"].revealed > *:nth-child(8) { transition-delay: 0.42s; }
[data-reveal="stagger"].revealed > * {
    opacity: 1;
    transform: translateY(0);
}

/* 8: Hero text reveal */
.hero-reveal > * {
    opacity: 0;
    transform: translateY(30px);
    transition: opacity 0.8s cubic-bezier(0.4, 0, 0.2, 1), transform 0.8s cubic-bezier(0.4, 0, 0.2, 1);
}
.hero-reveal.revealed > *:nth-child(1) { transition-delay: 0.1s; }
.hero-reveal.revealed > *:nth-child(2) { transition-delay: 0.3s; }
.hero-reveal.revealed > *:nth-child(3) { transition-delay: 0.5s; }
.hero-reveal.revealed > *:nth-child(4) { transition-delay: 0.7s; }
.hero-reveal.revealed > *:nth-child(5) { transition-delay: 0.9s; }
.hero-reveal.revealed > * {
    opacity: 1;
    transform: translateY(0);
}

/* ===== Reduced Motion ===== */
@media (prefers-reduced-motion: reduce) {
    [data-reveal],
    [data-reveal] > *,
    .hero-reveal > *,
    .card {
        transition: none !important;
        animation: none !important;
        opacity: 1 !important;
        transform: none !important;
        filter: none !important;
        clip-path: none !important;
    }
}

.no-js [data-reveal],
.no-js [data-reveal] > *,
.no-js .hero-reveal > * {
    opacity: 1;
    transform: none;
    filter: none;
    clip-path: none;
}

/* ===== FAQ Accordion ===== */
.faq-item .faq-question i.fa-chevron-down {
    transition: transform 0.3s ease;
}

.faq-item .faq-question.active i.fa-chevron-down {
    transform: rotate(180deg);
}

.faq-answer {
    max-height: 0;
    overflow: hidden;
    padding-top: 0;
    padding-bottom: 0;
    transition: max-height 0.4s ease-out, padding-top 0.3s ease-out, padding-bottom 0.3s ease-out;
}

.faq-answer.show {
    max-height: 1000px;
    padding-top: 0.25rem;
    padding-bottom: 1.5rem;
}

/* ===== Scroll to Top ===== */
#scroll-top {
    display: flex;
    opacity: 0;
    visibility: hidden;
    transition: opacity 0.3s ease, visibility 0.3s ease, transform 0.3s ease;
}

#scroll-top:hover {
    transform: translateY(-3px);
}

#scroll-top.show {
    opacity: 1;
    visibility: visible;
}

/* ===== CTA Gradient ===== */
.gradient-cta {
    background: linear-gradient(135deg, var(--gold-600) 0%, var(--gold-500) 50%, var(--gold-400) 100%);
}

/* ===== Scrollbar ===== */
::-webkit-scrollbar {
    width: 8px;
}

::-webkit-scrollbar-track {
    background: var(--warm-100);
}

::-webkit-scrollbar-thumb {
    background: var(--navy-700);
    border-radius: 4px;
}

::-webkit-scrollbar-thumb:hover {
    background: var(--navy-800);
}

/* ===== Section Spacing ===== */
section {
    scroll-margin-top: 80px;
}

/* ===== Counter ===== */
.counter {
    font-variant-numeric: tabular-nums;
    font-family: var(--font-en);
}

/* ===== Print ===== */
@media print {
    header, footer, #scroll-top {
        display: none;
    }
    section {
        page-break-inside: avoid;
    }
}

/* ===== Accessibility ===== */
.sr-only {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
    border-width: 0;
}

a:focus-visible,
button:focus-visible {
    outline: 3px solid var(--gold-500);
    outline-offset: 2px;
}

/* ===== Responsive Typography ===== */
@media (max-width: 640px) {
    h1 { font-size: 1.875rem; line-height: 1.2; }
    h2 { font-size: 1.5rem; line-height: 1.3; }
    h3 { font-size: 1.25rem; line-height: 1.4; }
}

/* ===== Certification Badge ===== */
@keyframes badge-glow {
    0%, 100% { box-shadow: 0 0 20px rgba(196, 147, 10, 0.15); }
    50% { box-shadow: 0 0 40px rgba(196, 147, 10, 0.3); }
}

.badge-glow {
    animation: badge-glow 3s ease-in-out infinite;
}

/* ===== Responsive Images ===== */
img {
    max-width: 100%;
    height: auto;
}

/* ===== Governance Card ===== */
.governance-card {
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.governance-card:hover {
    box-shadow: 0 12px 32px -4px rgba(13, 27, 42, 0.12);
    transform: translateY(-4px);
}

/* ===== Criteria Item ===== */
.criteria-item {
    transition: background-color 0.3s ease, transform 0.3s ease;
}

.criteria-item:hover {
    background-color: var(--warm-50);
    transform: translateX(4px);
}

/* ===== End of Design System v2.0 ===== */