/* ============================================
   Shelly Device Selector — 3-Step Wizard
   Inspired by shelly.com design language
   ============================================ */

:root {
    --color-primary: #0066FF;
    --color-primary-dark: #0052CC;
    --color-primary-light: #E8F0FE;
    --color-primary-glow: rgba(0, 102, 255, 0.12);
    --color-accent: #00C853;
    --color-accent-light: #E8F8EF;
    --color-dark: #0D1B2A;
    --color-dark-secondary: #1B2E44;
    --color-text: #1A1A2E;
    --color-text-secondary: #5A6577;
    --color-text-tertiary: #8892A4;
    --color-bg: #F7F8FC;
    --color-white: #FFFFFF;
    --color-border: #E2E6EF;
    --color-border-light: #F0F2F7;

    --radius-sm: 8px;
    --radius-md: 12px;
    --radius-lg: 16px;
    --radius-full: 9999px;

    --shadow-sm: 0 1px 3px rgba(13, 27, 42, 0.06);
    --shadow-md: 0 4px 12px rgba(13, 27, 42, 0.08);
    --shadow-lg: 0 8px 30px rgba(13, 27, 42, 0.1);
    --shadow-glow: 0 0 0 3px var(--color-primary-glow);

    --transition-fast: 150ms ease;
    --transition-normal: 250ms ease;
    --font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
}

*, *::before, *::after { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; -webkit-font-smoothing: antialiased; }
body {
    font-family: var(--font-family);
    color: var(--color-text);
    background: var(--color-bg);
    line-height: 1.6;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

/* ============================================
   Header
   ============================================ */
.header {
    border-bottom: 1px solid var(--color-border);
    position: sticky;
    top: 0;
    z-index: 100;
    backdrop-filter: blur(12px);
    background: rgba(255, 255, 255, 0.92);
}
.header-inner {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 24px;
    height: 56px;
    display: flex;
    align-items: center;
    justify-content: space-between;
}
.header-nav {
    display: flex;
    align-items: center;
    gap: 10px;
}
.logo {
    display: flex;
    align-items: center;
    gap: 12px;
}
.logo-svg {
    height: 22px;
    width: auto;
    color: var(--color-dark);
}
.logo-divider {
    width: 1px;
    height: 20px;
    background: var(--color-border);
}
.logo-subtitle {
    font-size: 13px;
    font-weight: 500;
    color: var(--color-text-secondary);
}

/* ─── Language Selector ──────────────────────── */
.lang-selector {
    position: relative;
}
.lang-btn {
    display: flex;
    align-items: center;
    gap: 6px;
    padding: 6px 12px;
    border: 1px solid var(--color-border);
    border-radius: var(--radius-full);
    background: var(--color-white);
    font-size: 12px;
    font-weight: 600;
    font-family: var(--font-family);
    color: var(--color-text-secondary);
    cursor: pointer;
    transition: all var(--transition-fast);
}
.lang-btn:hover {
    border-color: var(--color-text-tertiary);
    background: var(--color-bg);
}
.lang-flag { font-size: 16px; }
.lang-code { letter-spacing: 0.05em; }
.lang-dropdown {
    position: absolute;
    top: calc(100% + 6px);
    right: 0;
    background: var(--color-white);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-md);
    box-shadow: var(--shadow-lg);
    min-width: 160px;
    overflow: hidden;
    display: none;
    z-index: 200;
}
.lang-dropdown.open { display: block; }
.lang-option {
    display: flex;
    align-items: center;
    gap: 8px;
    width: 100%;
    padding: 10px 16px;
    border: none;
    background: none;
    font-size: 13px;
    font-weight: 500;
    font-family: var(--font-family);
    color: var(--color-text);
    cursor: pointer;
    transition: background var(--transition-fast);
}
.lang-option:hover { background: var(--color-bg); }
.lang-option.active {
    background: var(--color-primary-light);
    color: var(--color-primary);
    font-weight: 600;
}
.lang-option span { font-size: 16px; }

/* ─── Reset Button ───────────────────────────── */
.btn-reset {
    display: flex;
    align-items: center;
    gap: 6px;
    padding: 6px 14px;
    border: 1px solid var(--color-border);
    border-radius: var(--radius-full);
    background: var(--color-white);
    color: var(--color-text-secondary);
    font-size: 12px;
    font-weight: 500;
    font-family: var(--font-family);
    cursor: pointer;
    transition: all var(--transition-fast);
}
.btn-reset:hover {
    border-color: var(--color-text-tertiary);
    color: var(--color-text);
    background: var(--color-bg);
}

/* ============================================
   Hero
   ============================================ */
.hero {
    background: linear-gradient(135deg, var(--color-dark) 0%, var(--color-dark-secondary) 100%);
    color: var(--color-white);
    padding: 40px 24px 32px;
    text-align: center;
    position: relative;
    overflow: hidden;
}
.hero::before {
    content: '';
    position: absolute;
    top: -50%;
    right: -20%;
    width: 500px;
    height: 500px;
    background: radial-gradient(circle, rgba(0, 102, 255, 0.15) 0%, transparent 70%);
    pointer-events: none;
}
.hero-inner {
    position: relative;
    z-index: 1;
    max-width: 600px;
    margin: 0 auto 32px;
}
.hero h1 {
    font-size: 28px;
    font-weight: 700;
    letter-spacing: -0.02em;
    margin-bottom: 8px;
    line-height: 1.2;
}
.hero p {
    font-size: 15px;
    color: rgba(255, 255, 255, 0.65);
}

/* ─── Steps Indicator ────────────────────────── */
.hero-steps {
    display: flex;
    align-items: center;
    justify-content: center;
    position: relative;
    z-index: 1;
    max-width: 500px;
    margin: 0 auto;
}
.step {
    display: flex;
    align-items: center;
    gap: 8px;
    opacity: 0.4;
    transition: opacity var(--transition-normal);
}
.step.active { opacity: 1; }
.step.completed { opacity: 0.7; }
.step-number {
    width: 32px;
    height: 32px;
    border-radius: 50%;
    border: 2px solid rgba(255, 255, 255, 0.3);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 13px;
    font-weight: 600;
    transition: all var(--transition-normal);
}
.step.active .step-number {
    background: var(--color-primary);
    border-color: var(--color-primary);
}
.step.completed .step-number {
    background: var(--color-accent);
    border-color: var(--color-accent);
}
.step span {
    font-size: 13px;
    font-weight: 500;
}
.step-line {
    width: 48px;
    height: 2px;
    background: rgba(255, 255, 255, 0.15);
    margin: 0 12px;
}

/* ============================================
   Main
   ============================================ */
.main {
    flex: 1;
    max-width: 1200px;
    width: 100%;
    margin: 0 auto;
    padding: 36px 24px 80px;
}
.step-content {
    display: none;
    animation: fadeInUp 0.35s cubic-bezier(0.16, 1, 0.3, 1);
}
.step-content.active { display: block; }
@keyframes fadeInUp {
    from { opacity: 0; transform: translateY(12px); }
    to { opacity: 1; transform: translateY(0); }
}
.section-header {
    text-align: center;
    margin-bottom: 32px;
}
.section-header h2 {
    font-size: 22px;
    font-weight: 700;
    letter-spacing: -0.02em;
    margin-bottom: 6px;
    color: var(--color-dark);
}
.section-header p {
    font-size: 14px;
    color: var(--color-text-secondary);
}

/* ============================================
   Use Case Grid (Step 1)
   ============================================ */
.usecase-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
    gap: 12px;
}
.usecase-card {
    background: var(--color-white);
    border: 2px solid var(--color-border);
    border-radius: var(--radius-lg);
    padding: 20px 16px;
    cursor: pointer;
    transition: all var(--transition-normal);
    display: flex;
    flex-direction: column;
    align-items: flex-start;
    gap: 8px;
    position: relative;
}
.usecase-card:hover {
    border-color: var(--color-primary);
    box-shadow: var(--shadow-md), var(--shadow-glow);
    transform: translateY(-2px);
}
.usecase-card.selected {
    border-color: var(--color-primary);
    background: var(--color-primary-light);
    box-shadow: var(--shadow-glow);
}
.usecase-card.selected::after {
    content: '';
    position: absolute;
    top: 10px;
    right: 10px;
    width: 22px;
    height: 22px;
    background: var(--color-primary);
    border-radius: 50%;
    background-image: url("data:image/svg+xml,%3Csvg width='12' height='12' viewBox='0 0 24 24' fill='none' xmlns='http://www.w3.org/2000/svg'%3E%3Cpolyline points='20 6 9 17 4 12' stroke='white' stroke-width='3' stroke-linecap='round' stroke-linejoin='round'/%3E%3C/svg%3E");
    background-repeat: no-repeat;
    background-position: center;
    background-size: 12px;
}
.usecase-icon {
    width: 40px;
    height: 40px;
    border-radius: var(--radius-sm);
    background: var(--color-bg);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 20px;
}
.usecase-card.selected .usecase-icon {
    background: rgba(0, 102, 255, 0.12);
}
.usecase-card h3 {
    font-size: 14px;
    font-weight: 600;
    color: var(--color-dark);
    line-height: 1.3;
}
.usecase-card p {
    font-size: 12px;
    color: var(--color-text-secondary);
    line-height: 1.4;
}

/* ============================================
   Filters (Step 2)
   ============================================ */
.filters-container {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(340px, 1fr));
    gap: 16px;
    margin-bottom: 32px;
}
.filter-group {
    background: var(--color-white);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-lg);
    padding: 20px;
    transition: opacity var(--transition-normal);
}
.filter-group.filter-hidden { display: none; }
.filter-group-header {
    display: flex;
    align-items: center;
    gap: 10px;
    margin-bottom: 14px;
}
.filter-group-icon {
    width: 32px;
    height: 32px;
    border-radius: var(--radius-sm);
    background: var(--color-primary-light);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 16px;
    flex-shrink: 0;
}
.filter-group-header h3 {
    font-size: 13px;
    font-weight: 600;
    color: var(--color-dark);
}
.filter-group-header p {
    font-size: 11px;
    color: var(--color-text-tertiary);
    margin-top: 1px;
}
.filter-options {
    display: flex;
    flex-wrap: wrap;
    gap: 6px;
}
.filter-chip {
    display: inline-flex;
    align-items: center;
    gap: 4px;
    padding: 6px 14px;
    border: 1.5px solid var(--color-border);
    border-radius: var(--radius-full);
    background: var(--color-white);
    font-size: 12px;
    font-weight: 500;
    font-family: var(--font-family);
    color: var(--color-text-secondary);
    cursor: pointer;
    transition: all var(--transition-fast);
    white-space: nowrap;
}
.filter-chip:hover {
    border-color: var(--color-primary);
    color: var(--color-primary);
    background: var(--color-primary-light);
}
.filter-chip.active {
    border-color: var(--color-primary);
    background: var(--color-primary);
    color: var(--color-white);
}
.chip-check {
    display: none;
    width: 14px;
    height: 14px;
    align-items: center;
    justify-content: center;
}
.filter-chip.active .chip-check {
    display: inline-flex;
}
.filter-chip.active .chip-check svg { stroke: var(--color-white); }
.filter-chip.filter-unavailable {
    display: none;
}

/* ============================================
   Buttons
   ============================================ */
.step-actions {
    display: flex;
    justify-content: center;
    gap: 12px;
    margin-top: 36px;
}
.btn {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 11px 26px;
    border-radius: var(--radius-full);
    font-size: 14px;
    font-weight: 600;
    font-family: var(--font-family);
    cursor: pointer;
    transition: all var(--transition-fast);
    border: 2px solid transparent;
}
.btn:disabled {
    opacity: 0.4;
    cursor: not-allowed;
    transform: none !important;
}
.btn-primary {
    background: var(--color-primary);
    color: var(--color-white);
    border-color: var(--color-primary);
}
.btn-primary:hover:not(:disabled) {
    background: var(--color-primary-dark);
    border-color: var(--color-primary-dark);
    box-shadow: var(--shadow-md);
    transform: translateY(-1px);
}
.btn-count {
    font-size: 12px;
    opacity: 0.8;
}
.btn-secondary {
    background: var(--color-white);
    color: var(--color-text);
    border-color: var(--color-border);
}
.btn-secondary:hover {
    border-color: var(--color-text-tertiary);
    background: var(--color-bg);
}
.btn-outline {
    background: transparent;
    color: var(--color-text-secondary);
    border-color: var(--color-border);
}
.btn-outline:hover {
    border-color: var(--color-text-tertiary);
    color: var(--color-text);
    background: var(--color-white);
}

/* ============================================
   Results Summary (Step 3)
   ============================================ */
.results-summary {
    display: flex;
    flex-wrap: wrap;
    gap: 6px;
    justify-content: center;
    margin-bottom: 28px;
}
.summary-tag {
    display: inline-flex;
    align-items: center;
    gap: 5px;
    padding: 5px 12px;
    background: var(--color-primary-light);
    color: var(--color-primary);
    border-radius: var(--radius-full);
    font-size: 11px;
    font-weight: 600;
}

/* ============================================
   Results Grid (Step 3) — Product Cards
   ============================================ */
.results-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: 16px;
}
.result-card {
    background: var(--color-white);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-lg);
    overflow: hidden;
    transition: all var(--transition-normal);
    display: flex;
    flex-direction: column;
}
.result-card:hover {
    box-shadow: var(--shadow-lg);
    transform: translateY(-2px);
    border-color: var(--color-primary);
}

/* ─── Product Image ──────────────────────────── */
.result-card-image {
    width: 100%;
    height: 180px;
    background: linear-gradient(135deg, #f8f9fd 0%, #eef1f8 100%);
    display: flex;
    align-items: center;
    justify-content: center;
    overflow: hidden;
}
.result-card-image img {
    max-width: 70%;
    max-height: 150px;
    object-fit: contain;
    transition: transform var(--transition-normal);
}
.result-card:hover .result-card-image img {
    transform: scale(1.05);
}
.result-card-image.img-error {
    background: linear-gradient(135deg, var(--color-primary-light) 0%, #dce6f8 100%);
}
.img-placeholder {
    font-size: 36px;
    font-weight: 800;
    color: var(--color-primary);
    opacity: 0.3;
    letter-spacing: -0.02em;
}

/* ─── Card Body ──────────────────────────────── */
.result-card-body {
    padding: 18px;
    flex: 1;
    display: flex;
    flex-direction: column;
}
.result-card-series {
    font-size: 10px;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.08em;
    color: var(--color-primary);
    margin-bottom: 3px;
}
.result-card-name {
    font-size: 16px;
    font-weight: 700;
    color: var(--color-dark);
    letter-spacing: -0.02em;
    line-height: 1.3;
    margin-bottom: 14px;
}

/* ─── Specs Grid ─────────────────────────────── */
.result-card-specs {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 8px;
    padding: 12px 0;
    border-top: 1px solid var(--color-border-light);
}
.spec-item { display: flex; flex-direction: column; gap: 1px; }
.spec-item.spec-wide { grid-column: 1 / -1; }
.spec-label {
    font-size: 10px;
    font-weight: 500;
    color: var(--color-text-tertiary);
    text-transform: uppercase;
    letter-spacing: 0.05em;
}
.spec-value {
    font-size: 12px;
    font-weight: 600;
    color: var(--color-dark);
}

/* ─── Tags ───────────────────────────────────── */
.result-card-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 4px;
    margin-top: 10px;
}
.tag {
    padding: 2px 8px;
    border-radius: var(--radius-full);
    font-size: 10px;
    font-weight: 500;
    line-height: 1.6;
}
.tag-green { background: var(--color-accent-light); color: #1B7A3D; }
.tag-blue { background: var(--color-primary-light); color: var(--color-primary); }
.tag-gray { background: var(--color-bg); color: var(--color-text-secondary); }

/* ─── IDs ────────────────────────────────────── */
.result-card-ids {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
    margin-top: 10px;
    padding-top: 10px;
    border-top: 1px solid var(--color-border-light);
}
.id-item {
    font-size: 10px;
    color: var(--color-text-tertiary);
    font-variant-numeric: tabular-nums;
}
.id-label {
    font-weight: 700;
    color: var(--color-text-secondary);
    margin-right: 2px;
}

/* ─── KB Link ────────────────────────────────── */
.result-card-link {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    margin-top: 14px;
    padding-top: 12px;
    border-top: 1px solid var(--color-border-light);
    font-size: 13px;
    font-weight: 600;
    color: var(--color-primary);
    text-decoration: none;
    transition: color var(--transition-fast);
}
.result-card-link:hover {
    color: var(--color-primary-dark);
}

/* ─── Solution Guide Banner ──────────────────── */
.solution-guide {
    display: flex;
    align-items: center;
    gap: 16px;
    margin-top: 24px;
    padding: 20px 24px;
    background: linear-gradient(135deg, var(--color-accent-light) 0%, #d4f5e0 100%);
    border: 1px solid #b8e8c8;
    border-radius: var(--radius-lg);
}
.guide-icon {
    width: 44px;
    height: 44px;
    border-radius: var(--radius-md);
    background: rgba(0, 200, 83, 0.15);
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
    color: #1B7A3D;
}
.guide-content {
    flex: 1;
}
.guide-title {
    font-size: 14px;
    font-weight: 700;
    color: #1B7A3D;
    margin-bottom: 2px;
}
.guide-desc {
    font-size: 13px;
    color: #2D6A3E;
}
.guide-link {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    padding: 8px 18px;
    background: #1B7A3D;
    color: var(--color-white);
    border-radius: var(--radius-full);
    font-size: 13px;
    font-weight: 600;
    font-family: var(--font-family);
    text-decoration: none;
    white-space: nowrap;
    transition: all var(--transition-fast);
}
.guide-link:hover {
    background: #155F2F;
    box-shadow: var(--shadow-md);
    transform: translateY(-1px);
}

/* ─── No Results ─────────────────────────────── */
.no-results {
    display: flex;
    flex-direction: column;
    align-items: center;
    text-align: center;
    padding: 60px 24px;
    color: var(--color-text-tertiary);
}
.no-results svg { margin-bottom: 16px; opacity: 0.3; }
.no-results h3 {
    font-size: 18px;
    font-weight: 600;
    color: var(--color-text-secondary);
    margin-bottom: 8px;
}
.no-results p { font-size: 14px; }

/* ============================================
   Footer
   ============================================ */
.footer {
    background: var(--color-dark);
    color: rgba(255, 255, 255, 0.5);
    padding: 24px;
    text-align: center;
    margin-top: auto;
}
.footer-inner { max-width: 600px; margin: 0 auto; }
.footer p { font-size: 12px; line-height: 1.6; }
.footer-disclaimer { margin-top: 6px; font-size: 11px; }
.footer a { color: var(--color-primary); text-decoration: none; }
.footer a:hover { text-decoration: underline; }

/* ============================================
   Responsive
   ============================================ */
@media (max-width: 768px) {
    .hero h1 { font-size: 22px; }
    .hero { padding: 28px 20px 24px; }
    .step span { display: none; }
    .step-line { width: 32px; }
    .usecase-grid {
        grid-template-columns: repeat(auto-fill, minmax(150px, 1fr));
        gap: 10px;
    }
    .usecase-card { padding: 16px 14px; }
    .usecase-icon { width: 36px; height: 36px; font-size: 18px; }
    .filters-container { grid-template-columns: 1fr; }
    .results-grid { grid-template-columns: 1fr; }
    .main { padding: 24px 16px 60px; }
    .solution-guide {
        flex-direction: column;
        text-align: center;
    }
    .step-actions {
        flex-direction: column-reverse;
        align-items: stretch;
    }
    .btn { justify-content: center; }
}

@media (max-width: 480px) {
    .header-inner { padding: 0 16px; }
    .logo-subtitle, .logo-divider { display: none; }
    .usecase-grid { grid-template-columns: 1fr 1fr; }
    .hero h1 { font-size: 20px; }
    .result-card-image { height: 140px; }
}