/* ==========================================================
   ACMOBOOK UI SYSTEM
   Shared presentation layer — buttons, cards, forms,
   typography, spacing, loading, accessibility
========================================================== */

/* ----------------------------------------------------------
   SPACING SCALE
---------------------------------------------------------- */

:root {
    --space-1: 4px;
    --space-2: 8px;
    --space-3: 12px;
    --space-4: 16px;
    --space-5: 20px;
    --space-6: 24px;
    --space-8: 32px;
    --space-10: 40px;
    --space-12: 48px;
    --space-16: 64px;
    --space-20: 80px;

    /* Typography */
    --font-xs: 0.75rem;
    --font-sm: 0.875rem;
    --font-base: 1rem;
    --font-lg: 1.125rem;
    --font-xl: 1.25rem;
    --font-2xl: 1.5rem;
    --font-3xl: 1.875rem;
    --font-4xl: 2.25rem;
    --font-5xl: 3rem;

    --leading-tight: 1.25;
    --leading-normal: 1.5;
    --leading-relaxed: 1.75;

    /* Focus ring */
    --focus-ring: 0 0 0 3px rgba(108, 99, 255, 0.35);
    --focus-ring-offset: 2px;

    /* Touch target minimum */
    --touch-min: 44px;
}

/* ----------------------------------------------------------
   SKIP LINK (accessibility)
---------------------------------------------------------- */

.skip-to-content {
    position: absolute;
    top: -100%;
    left: var(--space-4);
    z-index: 1000000;
    padding: var(--space-3) var(--space-5);
    background: var(--primary, #6C63FF);
    color: #fff;
    font-weight: 600;
    font-size: var(--font-sm);
    border-radius: var(--radius-sm, 12px);
    text-decoration: none;
    transition: top 0.2s ease;
}

.skip-to-content:focus {
    top: var(--space-4);
    outline: none;
    box-shadow: var(--focus-ring);
}

/* ----------------------------------------------------------
   SITE MAIN LAYOUT
---------------------------------------------------------- */

.site-main {
    min-height: calc(100vh - var(--header-height, 90px));
    padding-top: var(--space-4);
}

@media (min-width: 768px) {
    .site-main {
        padding-top: var(--space-6);
    }
}

@media (min-width: 992px) {
    .site-main {
        padding-top: var(--space-8);
    }
}

/* ----------------------------------------------------------
   PAGE HERO (static / content pages)
---------------------------------------------------------- */

.acmo-page-hero {
    background: linear-gradient(180deg, #fff 0%, var(--background, #F8FAFC) 100%);
    padding: var(--space-12) 0 var(--space-10);
    border-bottom: 1px solid var(--border, #E2E8F0);
    margin-bottom: var(--space-10);
}

.acmo-page-hero h1 {
    font-size: clamp(1.75rem, 4vw, 2.75rem);
    font-weight: 800;
    color: var(--text, #0F172A);
    letter-spacing: -0.02em;
    line-height: var(--leading-tight);
    margin-bottom: var(--space-4);
}

.acmo-page-hero .acmo-page-lead {
    font-size: var(--font-lg);
    color: var(--muted, #64748B);
    line-height: var(--leading-relaxed);
    max-width: 640px;
}

.acmo-page-content {
    padding-bottom: var(--space-16);
}

.acmo-page-content .content {
    font-size: var(--font-base);
    line-height: var(--leading-relaxed);
    color: var(--text-light, #334155);
}

.acmo-page-content .content h2,
.acmo-page-content .content h3 {
    color: var(--text, #0F172A);
    font-weight: 700;
    margin-top: var(--space-8);
    margin-bottom: var(--space-4);
}

.acmo-page-content .content h2 {
    font-size: var(--font-2xl);
}

.acmo-page-content .content h3 {
    font-size: var(--font-xl);
}

.acmo-page-content .content p {
    margin-bottom: var(--space-4);
}

.acmo-page-content .content ul,
.acmo-page-content .content ol {
    margin-bottom: var(--space-4);
    padding-left: var(--space-6);
}

.acmo-page-content .content li {
    margin-bottom: var(--space-2);
}

.acmo-page-content .content a {
    color: var(--primary, #6C63FF);
    text-decoration: underline;
    text-underline-offset: 3px;
}

.acmo-page-content .content a:hover {
    color: var(--primary-dark, #5648F5);
}

/* ----------------------------------------------------------
   BUTTONS
---------------------------------------------------------- */

.acmo-btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: var(--space-2);
    min-height: var(--touch-min);
    padding: 0 var(--space-6);
    font-size: var(--font-sm);
    font-weight: 600;
    line-height: 1;
    border-radius: var(--radius-sm, 12px);
    border: 2px solid transparent;
    cursor: pointer;
    text-decoration: none;
    transition: transform var(--transition-fast, 0.18s),
                box-shadow var(--transition-fast, 0.18s),
                background var(--transition-fast, 0.18s),
                color var(--transition-fast, 0.18s);
    white-space: nowrap;
}

.acmo-btn:focus-visible {
    outline: none;
    box-shadow: var(--focus-ring);
}

.acmo-btn:disabled,
.acmo-btn.is-loading {
    opacity: 0.6;
    pointer-events: none;
    cursor: not-allowed;
}

.acmo-btn-primary {
    background: var(--gradient-primary, linear-gradient(135deg, #6C63FF, #06B6D4));
    color: #fff;
    box-shadow: 0 8px 24px rgba(108, 99, 255, 0.25);
}

.acmo-btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 14px 32px rgba(108, 99, 255, 0.35);
}

.acmo-btn-secondary {
    background: var(--surface, #fff);
    color: var(--text, #0F172A);
    border-color: var(--border, #E2E8F0);
}

.acmo-btn-secondary:hover {
    border-color: var(--primary, #6C63FF);
    color: var(--primary, #6C63FF);
    transform: translateY(-1px);
}

.acmo-btn-ghost {
    background: transparent;
    color: var(--primary, #6C63FF);
}

.acmo-btn-ghost:hover {
    background: var(--primary-light, #EEF2FF);
}

.acmo-btn-sm {
    min-height: 36px;
    padding: 0 var(--space-4);
    font-size: var(--font-xs);
}

.acmo-btn-lg {
    min-height: 52px;
    padding: 0 var(--space-8);
    font-size: var(--font-base);
    border-radius: var(--radius-md, 16px);
}

/* ----------------------------------------------------------
   CARDS
---------------------------------------------------------- */

.acmo-card {
    background: var(--surface, #fff);
    border: 1px solid var(--border-light, #EDF2F7);
    border-radius: var(--radius-md, 16px);
    padding: var(--space-6);
    box-shadow: var(--shadow-sm, 0 8px 24px rgba(15, 23, 42, 0.06));
    transition: transform var(--transition, 0.3s),
                box-shadow var(--transition, 0.3s);
}

.acmo-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-md, 0 18px 40px rgba(15, 23, 42, 0.08));
}

.acmo-card-flat {
    box-shadow: none;
}

.acmo-card-flat:hover {
    box-shadow: var(--shadow-sm);
}

/* ----------------------------------------------------------
   FORMS
---------------------------------------------------------- */

.acmo-form-group {
    margin-bottom: var(--space-5);
}

.acmo-label {
    display: block;
    font-size: var(--font-sm);
    font-weight: 600;
    color: var(--text, #0F172A);
    margin-bottom: var(--space-2);
}

.acmo-input,
.acmo-select,
.acmo-textarea {
    display: block;
    width: 100%;
    min-height: var(--touch-min);
    padding: var(--space-3) var(--space-4);
    font-size: var(--font-base);
    font-family: inherit;
    color: var(--text, #0F172A);
    background: var(--surface, #fff);
    border: 1.5px solid var(--border, #E2E8F0);
    border-radius: var(--radius-sm, 12px);
    transition: border-color var(--transition-fast, 0.18s),
                box-shadow var(--transition-fast, 0.18s);
}

.acmo-textarea {
    min-height: 120px;
    resize: vertical;
}

.acmo-input::placeholder,
.acmo-textarea::placeholder {
    color: var(--muted, #64748B);
}

.acmo-input:focus,
.acmo-select:focus,
.acmo-textarea:focus {
    outline: none;
    border-color: var(--primary, #6C63FF);
    box-shadow: var(--focus-ring);
}

.acmo-input.is-invalid,
.acmo-textarea.is-invalid {
    border-color: var(--danger, #EF4444);
}

.acmo-form-hint {
    font-size: var(--font-xs);
    color: var(--muted, #64748B);
    margin-top: var(--space-2);
}

.acmo-form-error {
    font-size: var(--font-xs);
    color: var(--danger, #EF4444);
    margin-top: var(--space-2);
}

/* ----------------------------------------------------------
   LOADING STATES
---------------------------------------------------------- */

.acmo-spinner {
    display: inline-block;
    width: 20px;
    height: 20px;
    border: 2.5px solid rgba(108, 99, 255, 0.2);
    border-top-color: var(--primary, #6C63FF);
    border-radius: 50%;
    animation: acmo-spin 0.7s linear infinite;
}

.acmo-spinner-lg {
    width: 36px;
    height: 36px;
    border-width: 3px;
}

@keyframes acmo-spin {
    to { transform: rotate(360deg); }
}

.acmo-skeleton {
    background: linear-gradient(90deg, #f1f5f9 25%, #e2e8f0 50%, #f1f5f9 75%);
    background-size: 200% 100%;
    animation: acmo-shimmer 1.4s ease infinite;
    border-radius: var(--radius-xs, 8px);
}

.acmo-skeleton-text {
    height: 14px;
    margin-bottom: var(--space-2);
}

.acmo-skeleton-title {
    height: 24px;
    width: 60%;
    margin-bottom: var(--space-3);
}

.acmo-skeleton-avatar {
    width: 48px;
    height: 48px;
    border-radius: 50%;
}

.acmo-skeleton-card {
    height: 200px;
    border-radius: var(--radius-md, 16px);
}

@keyframes acmo-shimmer {
    0% { background-position: 200% 0; }
    100% { background-position: -200% 0; }
}

.acmo-loading-overlay {
    position: absolute;
    inset: 0;
    display: flex;
    align-items: center;
    justify-content: center;
    background: rgba(255, 255, 255, 0.75);
    backdrop-filter: blur(4px);
    border-radius: inherit;
    z-index: 10;
}

/* ----------------------------------------------------------
   ANIMATIONS (scroll reveal)
---------------------------------------------------------- */

.fade-up,
.fade-left,
.fade-right,
.zoom-in {
    opacity: 0;
    transition: opacity 0.6s ease, transform 0.6s ease;
}

.fade-up {
    transform: translateY(28px);
}

.fade-left {
    transform: translateX(-28px);
}

.fade-right {
    transform: translateX(28px);
}

.zoom-in {
    transform: scale(0.94);
}

.fade-up.show,
.fade-left.show,
.fade-right.show,
.zoom-in.show {
    opacity: 1;
    transform: none;
}

/* ----------------------------------------------------------
   FOCUS & ACCESSIBILITY
---------------------------------------------------------- */

:focus-visible {
    outline: none;
    box-shadow: var(--focus-ring);
}

button:focus-visible,
a:focus-visible,
input:focus-visible,
select:focus-visible,
textarea:focus-visible {
    outline: none;
    box-shadow: var(--focus-ring);
}

.visually-hidden {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
    border: 0;
}

/* ----------------------------------------------------------
   REDUCED MOTION
---------------------------------------------------------- */

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

    .fade-up,
    .fade-left,
    .fade-right,
    .zoom-in {
        opacity: 1;
        transform: none;
    }

    .acmo-card:hover,
    .acmo-btn-primary:hover,
    .acmo-btn-secondary:hover {
        transform: none;
    }
}

/* ----------------------------------------------------------
   TABLET UTILITIES
---------------------------------------------------------- */

@media (min-width: 768px) and (max-width: 991.98px) {
    .tablet-stack {
        flex-direction: column !important;
    }

    .tablet-full {
        width: 100% !important;
    }
}

/* ----------------------------------------------------------
   DARK MODE TOKENS (opt-in via data-theme)
---------------------------------------------------------- */

[data-theme="dark"] {
    --background: #0F172A;
    --surface: #1E293B;
    --surface-2: #334155;
    --text: #F1F5F9;
    --text-light: #CBD5E1;
    --muted: #94A3B8;
    --border: #334155;
    --border-light: #1E293B;
    --primary-light: rgba(108, 99, 255, 0.15);
}

[data-theme="dark"] body {
    background: var(--background);
    color: var(--text);
}

[data-theme="dark"] .acmo-card {
    background: var(--surface);
    border-color: var(--border);
}

[data-theme="dark"] .acmo-input,
[data-theme="dark"] .acmo-textarea,
[data-theme="dark"] .acmo-select {
    background: var(--surface-2);
    border-color: var(--border);
    color: var(--text);
}

[data-theme="dark"] .acmo-page-hero {
    background: linear-gradient(180deg, var(--surface) 0%, var(--background) 100%);
}

[data-theme="dark"] .acmo-skeleton {
    background: linear-gradient(90deg, #1e293b 25%, #334155 50%, #1e293b 75%);
    background-size: 200% 100%;
}

/* ----------------------------------------------------------
   MARKETPLACE EMPTY STATE
---------------------------------------------------------- */

.mkt-empty-state {
    text-align: center;
    padding: var(--space-12) var(--space-6);
    background: #fff;
    border: 1px dashed #E2E8F0;
    border-radius: 20px;
}

.mkt-empty-state__icon {
    width: 64px;
    height: 64px;
    margin: 0 auto var(--space-4);
    display: grid;
    place-items: center;
    border-radius: 50%;
    background: rgba(108, 99, 255, 0.1);
    color: var(--primary, #6C63FF);
    font-size: 1.5rem;
}

.mkt-empty-state__title {
    font-size: var(--font-xl);
    font-weight: 700;
    margin-bottom: var(--space-2);
}

.mkt-empty-state__text {
    color: #64748B;
    max-width: 420px;
    margin: 0 auto var(--space-5);
}

.mkt-btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-height: var(--touch-min);
    padding: 0 var(--space-5);
    border-radius: 12px;
    font-weight: 600;
    text-decoration: none;
    transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.mkt-btn--primary {
    background: var(--primary, #6C63FF);
    color: #fff;
}

.mkt-btn--outline {
    border: 1px solid #E2E8F0;
    color: #0F172A;
    background: #fff;
}

.mkt-btn:hover {
    transform: translateY(-1px);
}

/* ----------------------------------------------------------
   ERROR PAGES
---------------------------------------------------------- */

.acmo-error-page {
    min-height: 60vh;
    display: grid;
    place-items: center;
    padding: var(--space-12) var(--space-4);
}

.acmo-error-page__inner {
    max-width: 560px;
    text-align: center;
}

.acmo-error-page__code {
    font-size: clamp(3rem, 8vw, 5rem);
    font-weight: 800;
    line-height: 1;
    color: rgba(108, 99, 255, 0.2);
    margin-bottom: var(--space-2);
}

.acmo-error-page__icon {
    font-size: 2rem;
    color: var(--primary, #6C63FF);
    margin-bottom: var(--space-4);
}

.acmo-error-page__title {
    font-size: var(--font-3xl);
    font-weight: 700;
    margin-bottom: var(--space-3);
}

.acmo-error-page__text {
    color: #64748B;
    margin-bottom: var(--space-6);
}

.acmo-error-page__actions {
    display: flex;
    flex-wrap: wrap;
    gap: var(--space-3);
    justify-content: center;
}