/* button system */

.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 0.75rem;
    padding: 0.85rem 1.75rem;
    font-family: var(--font-mono);
    font-size: 0.8rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.15em;
    cursor: pointer;
    border: 1px solid transparent;
    border-radius: var(--radius-md);
    transition: all 0.4s cubic-bezier(0.16, 1, 0.3, 1);
    text-decoration: none;
    white-space: nowrap;
    position: relative;
    overflow: hidden;
    outline: none;
}

.btn:active {
    transform: scale(0.98);
}

/* primary button - solid black */
.btn-primary {
    background: #111;
    color: #fff;
    border: none;
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.1);
}

.btn-primary:hover {
    background: #000;
    transform: translateY(-3px);
    box-shadow: 0 15px 30px rgba(0, 0, 0, 0.15);
}

.btn-primary .btn-icon {
    display: inline-block;
    transition: transform 0.4s cubic-bezier(0.16, 1, 0.3, 1);
}

.btn-primary:hover .btn-icon {
    transform: translateX(8px) scale(1.1);
}

/* secondary button - glassy/light */
.btn-secondary {
    background: rgba(255, 255, 255, 0.5);
    color: var(--text-color);
    border: 1px solid rgba(0, 0, 0, 0.08);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
}

.btn-secondary:hover {
    background: rgba(0, 0, 0, 0.05);
    border-color: var(--text-color);
    transform: translateY(-3px);
    box-shadow: 0 10px 25px rgba(0, 0, 0, 0.05);
}

/* outline button - transparent */
.btn-outline {
    background: transparent;
    border: 1px solid var(--text-color);
    color: var(--text-color);
}

.btn-outline:hover {
    background: var(--text-color);
    color: #fff;
    transform: translateY(-3px);
    box-shadow: 0 10px 25px rgba(0, 0, 0, 0.1);
}

/* modifier: full width */
.btn-full,
.full-width {
    width: 100% !important;
}

/* modifier: small */
.btn-sm {
    padding: 0.5rem 1.25rem;
    font-size: 0.65rem;
    border-radius: var(--radius-sm);
    letter-spacing: 0.1em;
}

/* color modifiers for outline */
.btn-outline.orange {
    border-color: #c2410c;
    color: #c2410c;
}

.btn-outline.orange:hover {
    background: #c2410c;
    color: #fff;
    border-color: #c2410c;
}

.btn-outline.red {
    border-color: #b91c1c;
    color: #b91c1c;
}

.btn-outline.red:hover {
    background: #b91c1c;
    color: #fff;
    border-color: #b91c1c;
}

.btn-outline.blue {
    border-color: var(--accent-color);
    color: var(--accent-color);
}

.btn-outline.blue:hover {
    background: var(--accent-color);
    color: #fff;
    border-color: var(--accent-color);
}

/* icon enhancement */
.btn-icon-alt {
    background: none;
    border: none;
    cursor: pointer;
    border-radius: 50%;
    padding: 0.5rem;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all 0.3s;
}

.btn-icon-alt:hover {
    background: rgba(0, 0, 0, 0.05);
}

/* scanning ui integration */
/* d-hashing scanning ui */

/* d-hashing scanning ui - premium light */
.ai-scan-container {
    margin-top: 1.5rem;
    padding: 1.5rem;
    background: #f8f9fc;
    /* light premium background */
    border: 1px solid var(--border-color);
    border-radius: 8px;
    font-family: var(--font-mono);
    position: relative;
    overflow: hidden;
    display: none;
    /* hidden by default */
    box-shadow: inset 0 2px 10px rgba(0, 0, 0, 0.02);
}

.ai-scan-container.active {
    display: block;
    animation: fadeInUp 0.5s ease-out;
}

.scan-progress-bar {
    height: 3px;
    background: var(--accent-color);
    width: 0%;
    margin-top: 1rem;
    border-radius: 2px;
    transition: width 0.1s linear;
}

.scanning-line-overlay {
    display: none;
}

@keyframes scanMove {
    from {
        top: -100%;
    }

    to {
        top: 100%;
    }
}

@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(10px);
    }

    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.match-item {
    margin-top: 0.5rem;
    padding-left: 1rem;
    border-left: 1px solid rgb(0, 115, 255);
    opacity: 0;
    animation: fadeInUp 0.4s ease-out forwards;
}

.btn-text {
    background: none;
    border: none;
    font-family: var(--font-mono);
    font-size: 0.85rem;
    text-transform: uppercase;
    cursor: pointer;
    color: var(--muted-text);
    letter-spacing: 0.2em;
    padding: 1rem 2rem;
    transition: all 0.3s ease;
    display: flex;
    align-items: center;
    justify-content: center;
}

.btn-text:hover {
    color: var(--text-color);
    letter-spacing: 0.25em;
    transform: scale(1.05);
}


/* split layout (how it works) */
.split-layout {
    display: flex;
    max-width: 1400px;
    margin: 0 auto;
    gap: 4rem;
}


.split-left {
    flex: 1;
    position: sticky;
    top: 0;
    height: 100vh;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    text-align: center;
    z-index: 10;
}

.split-right {
    flex: 1;
    padding-top: 35vh;
    /* center first card */
    padding-bottom: 50vh;
}

.step-preview {
    max-width: 600px;
    padding: 0;
}

.label-tech {
    font-family: var(--font-mono);
    font-size: 1.3rem;
    color: var(--accent-color);
    display: block;
    text-align: left;
}

.preview-title {
    font-size: clamp(3rem, 7vw, 6rem);
    font-weight: 800;
    line-height: 1.1;
    margin: 1.5rem 0 1.5rem 0;
    text-align: center;
    color: var(--text-color);
    letter-spacing: -0.02em;
}

.preview-desc {
    font-size: clamp(1rem, 1.2vw, 1.25rem);
    color: var(--muted-text);
    max-width: 480px;
    text-align: center;
    line-height: 1.6;
    opacity: 0.9;
    margin: 0 auto;
}



.step-item {
    padding: 3rem;
    background: rgba(255, 255, 255, 0.4);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    border: 1px solid rgba(0, 0, 0, 0.05);
    border-radius: 40px;
    margin-bottom: 5vh;
    opacity: 0.3;
    transform: scale(0.95);
    transition: all 0.8s cubic-bezier(0.16, 1, 0.3, 1);
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.02);
}

.step-item.active {
    opacity: 1;
    transform: scale(1);
    background: rgba(255, 255, 255, 0.9);
    border-color: rgba(0, 78, 204, 0.1);
    box-shadow: 0 40px 80px rgba(0, 50, 150, 0.1);
}

.step-num {
    font-family: var(--font-mono);
    font-size: 0.8rem;
    font-weight: 700;
    color: var(--accent-color);
    letter-spacing: 0.2em;
    margin-bottom: 1.5rem;
    display: block;
}

.step-item h3 {
    font-size: 2.8rem;
    font-weight: 800;
    margin-bottom: 1.5rem;
    letter-spacing: -0.02em;
}

.step-item p {
    font-size: 1.1rem;
    line-height: 1.7;
    color: var(--muted-text);
    max-width: 400px;
}

@keyframes textFadeIn {
    from {
        opacity: 0;
        transform: translateY(10px);
        filter: blur(5px);
    }

    to {
        opacity: 1;
        transform: translateY(0);
        filter: blur(0);
    }
}

/* scroll hint */
.scroll-hint {
    position: relative;
    margin-top: 3rem;
    display: flex;
    flex-direction: column;
    align-items: center;
    text-align: center;
    max-width: 600px;
    width: 100%;
    gap: 1.5rem;
    pointer-events: none;
    transition: opacity 0.5s ease;
}


.hint-text {
    font-family: var(--font-mono);
    font-size: 0.7rem;
    letter-spacing: 0.3em;
    color: var(--accent-color);
    /* reverted to blue */
    font-weight: 500;
    text-transform: uppercase;
}

.hint-line {
    width: 2px;
    height: 70px;
    /* slightly longer */
    background: linear-gradient(to bottom, rgba(0, 78, 204, 0.3), transparent);
    position: relative;
    overflow: hidden;
}

.hint-line::after {
    content: '';
    position: absolute;
    top: -100%;
    left: 0;
    width: 100%;
    height: 100%;
    background: var(--accent-color);
    /* blue flow */
    box-shadow: 0 0 10px var(--accent-color);
    /* glow for visibility */
    animation: hintLineFlow 1.5s cubic-bezier(0.16, 1, 0.3, 1) infinite;
}

@keyframes hintLineFlow {
    0% {
        top: -100%;
    }

    50%,
    100% {
        top: 100%;
    }
}

/*  sources header button - */
.btn-ghost-xs {
    background: none;
    border: none;
    padding: 4px 8px;
    font-size: 11px;
    font-family: var(--font-mono, monospace);
    letter-spacing: 0.08em;
    color: var(--muted-text, #6A7180);
    cursor: pointer;
    opacity: 0.7;
}

.btn-ghost-xs:hover {
    opacity: 1;
}

/*  site footer bar - */
.site-footer-bar {
    display: none;
    align-items: center;
    justify-content: space-between;
    flex-wrap: wrap;
    gap: 6px;
    padding: 7px clamp(1rem, 4vw, 3rem);
    background: var(--bg-color, #f8f9fb);
    border-top: 1px solid var(--border-color);
    font-size: 11px;
    color: var(--muted-text, #6A7180);
    position: relative;
    z-index: 2;
}

.sfb-copy {
    font-family: var(--font-mono, monospace);
}

.sfb-link {
    background: none;
    border: none;
    padding: 0;
    font-size: 12px;
    font-family: var(--font-mono, monospace);
    color: var(--accent-color, #2563EB);
    cursor: pointer;
    text-decoration: underline;
    text-underline-offset: 3px;
}

.sfb-link:hover {
    opacity: 0.75;
}

/*  semantic site footer  */
.site-footer {
    display: none;
    text-align: center;
    padding: 1.25rem clamp(1rem, 4vw, 3rem);
    font-size: 11px;
    font-family: var(--font-mono, monospace);
    color: var(--muted-text, #6A7180);
    border-top: 1px solid var(--border-color);
    background: var(--bg-color, #f8f9fb);
}

.site-footer p {
    margin: 0;
}

/*  sources modal body  */
.sources-modal-box {
    max-width: 740px;
}

.sources-body {
    padding: 0 0.25rem;
    max-height: 60vh;
    overflow-y: auto;
}

.sources-note {
    font-size: 13px;
    line-height: 1.6;
    color: var(--muted-text, #6A7180);
    margin-bottom: 1.5rem;
    padding: 12px 14px;
    background: rgba(37, 99, 235, 0.05);
    border-left: 3px solid var(--accent-color, #2563EB);
    border-radius: 0 6px 6px 0;
}

.sources-body h4 {
    font-size: 11px;
    letter-spacing: 0.15em;
    text-transform: uppercase;
    color: var(--muted-text, #6A7180);
    margin: 1.5rem 0 0.6rem;
}

.sources-table {
    width: 100%;
    border-collapse: collapse;
    font-size: 13px;
    margin-bottom: 0.5rem;
}

.sources-table th {
    text-align: left;
    padding: 6px 10px;
    background: var(--border-color);
    font-weight: 600;
    font-size: 11px;
    letter-spacing: 0.06em;
    text-transform: uppercase;
}

.sources-table td {
    padding: 7px 10px;
    border-bottom: 1px solid var(--border-color);
    vertical-align: top;
}

.sources-table a {
    color: var(--accent-color, #2563EB);
}