/**
 * Structural layout shell — skin-agnostic grid, uses CSS variables from active skin.
 */

.sdc-shell {
    width: 100%;
    max-width: var(--sdc-shell-max, 72rem);
    margin-inline: auto;
    padding-inline: var(--sdc-shell-pad, clamp(1rem, 4vw, 2.5rem));
}

.sdc-shell--wide {
    max-width: 80rem;
}

.sdc-shell--narrow {
    max-width: 42rem;
}

/* Swiss hero zone */
.sdc-hero-zone {
    position: relative;
    background-color: var(--background-primary, #fff);
    background-image:
        linear-gradient(var(--sdc-grid-line, rgba(0, 0, 0, 0.06)) 1px, transparent 1px),
        linear-gradient(90deg, var(--sdc-grid-line, rgba(0, 0, 0, 0.06)) 1px, transparent 1px);
    background-size: 24px 24px;
    padding-block: clamp(2rem, 6vw, 4rem) clamp(1.5rem, 4vw, 3rem);
}

.sdc-hero-zone__inner {
    display: flex;
    flex-direction: column;
    align-items: center;
    text-align: center;
    gap: clamp(1rem, 3vw, 1.75rem);
}

.sdc-hero__headline {
    margin: 0;
    font-family: var(--font-family-display, inherit);
    font-size: clamp(2rem, 5.5vw, 3.75rem);
    font-weight: 800;
    line-height: 1.05;
    letter-spacing: -0.04em;
    color: var(--text-primary, #0a0a0a);
    max-width: 18ch;
}

.sdc-hero__accent {
    text-decoration: underline;
    text-decoration-color: var(--sdc-accent, var(--primary-color, #e11d1d));
    text-decoration-thickness: 0.12em;
    text-underline-offset: 0.08em;
}

.sdc-hero__sub {
    margin: 0;
    max-width: 38rem;
    font-size: clamp(0.9375rem, 2vw, 1.125rem);
    line-height: 1.6;
    color: var(--text-secondary, #525252);
}

.sdc-hero__actions {
    display: flex;
    flex-wrap: wrap;
    gap: 0.75rem;
    justify-content: center;
    align-items: center;
}

.sdc-hero__cta {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
    padding: 0.875rem 1.5rem;
    font-size: 0.75rem;
    font-weight: 700;
    letter-spacing: 0.06em;
    text-transform: uppercase;
    text-decoration: none;
    border-radius: var(--border-radius, 4px);
    transition: transform 0.15s ease, background 0.15s ease;
    border: 1px solid transparent;
    cursor: pointer;
    font-family: inherit;
}

.sdc-hero__cta--primary {
    background: var(--sdc-accent, var(--primary-color, #e11d1d));
    color: #fff;
    border-color: var(--sdc-accent, var(--primary-color, #e11d1d));
}

.sdc-hero__cta--primary:hover {
    background: var(--primary-color-dark, #b91c1c);
    color: #fff;
    transform: translateY(-1px);
}

.sdc-hero__cta--secondary {
    background: transparent;
    color: var(--sdc-ink, #0a0a0a);
    border-color: var(--sdc-ink, #0a0a0a);
}

.sdc-hero__cta--secondary:hover {
    background: var(--background-secondary, #f5f5f5);
    color: var(--sdc-ink, #0a0a0a);
}

.sdc-hero__cta svg {
    flex-shrink: 0;
}

/* Stats bar */
.sdc-stats {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: clamp(1rem, 3vw, 2rem);
    width: 100%;
    max-width: 48rem;
    margin-top: 0.5rem;
    padding-top: clamp(1rem, 3vw, 2rem);
    border-top: 1px solid var(--border-light, #e5e5e5);
}

.sdc-stats__item {
    text-align: center;
}

.sdc-stats__value {
    display: block;
    font-size: clamp(1.5rem, 4vw, 2.25rem);
    font-weight: 800;
    letter-spacing: -0.03em;
    color: var(--text-primary, #0a0a0a);
    line-height: 1.1;
}

.sdc-stats__label {
    display: block;
    margin-top: 0.35rem;
    font-size: 0.6875rem;
    font-weight: 600;
    letter-spacing: 0.08em;
    text-transform: uppercase;
    color: var(--text-tertiary, #737373);
}

/* Interactive sandbox */
.sdc-sandbox {
    width: 100%;
    max-width: 40rem;
    margin-top: clamp(1.5rem, 4vw, 2.5rem);
    text-align: left;
}

.sdc-sandbox__window {
    background: var(--background-elevated, #fff);
    border: 1px solid var(--sdc-ink, #0a0a0a);
    box-shadow: var(--shadow-md, 6px 6px 0 #0a0a0a);
    border-radius: var(--border-radius, 4px);
    overflow: hidden;
}

.sdc-sandbox__chrome {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0.625rem 1rem;
    border-bottom: 1px solid var(--border-light, #e5e5e5);
    background: var(--background-secondary, #fafafa);
}

.sdc-sandbox__dots {
    display: flex;
    gap: 0.375rem;
}

.sdc-sandbox__dot {
    width: 0.625rem;
    height: 0.625rem;
    border-radius: 50%;
    border: 1px solid rgba(0, 0, 0, 0.15);
}

.sdc-sandbox__dot--red { background: #ff5f57; }
.sdc-sandbox__dot--yellow { background: #febc2e; }
.sdc-sandbox__dot--green { background: #28c840; }

.sdc-sandbox__meta {
    font-family: var(--font-family-mono, monospace);
    font-size: 0.625rem;
    letter-spacing: 0.06em;
    color: var(--text-tertiary, #737373);
    text-transform: uppercase;
}

.sdc-sandbox__body {
    padding: 1.25rem 1.25rem 1rem;
}

.sdc-sandbox__header {
    display: flex;
    align-items: flex-start;
    justify-content: space-between;
    gap: 1rem;
    margin-bottom: 1rem;
}

.sdc-sandbox__title {
    margin: 0;
    font-size: 0.9375rem;
    font-weight: 700;
    color: var(--text-primary, #0a0a0a);
}

.sdc-sandbox__progress {
    font-size: 0.625rem;
    font-weight: 700;
    letter-spacing: 0.06em;
    text-transform: uppercase;
    color: var(--text-tertiary, #737373);
    white-space: nowrap;
}

.sdc-sandbox__tasks {
    list-style: none;
    margin: 0 0 1rem;
    padding: 0;
    display: flex;
    flex-direction: column;
    gap: 0.625rem;
}

.sdc-sandbox__task {
    display: grid;
    grid-template-columns: auto 1fr auto;
    align-items: center;
    gap: 0.75rem;
    padding: 0.625rem 0;
    border-bottom: 1px solid var(--border-light, #e5e5e5);
}

.sdc-sandbox__task:last-child {
    border-bottom: none;
}

.sdc-sandbox__task input[type="checkbox"] {
    width: 1.125rem;
    height: 1.125rem;
    accent-color: var(--sdc-accent, #e11d1d);
    cursor: pointer;
}

.sdc-sandbox__task-label {
    font-size: 0.875rem;
    color: var(--text-primary, #0a0a0a);
    cursor: pointer;
}

.sdc-sandbox__task.is-done .sdc-sandbox__task-label {
    color: var(--text-muted, #a3a3a3);
    text-decoration: line-through;
}

.sdc-sandbox__tag {
    font-size: 0.5625rem;
    font-weight: 700;
    letter-spacing: 0.06em;
    text-transform: uppercase;
    padding: 0.25rem 0.5rem;
    border-radius: 2px;
    border: 1px solid var(--border-light, #e5e5e5);
    color: var(--text-secondary, #525252);
    background: var(--background-secondary, #f5f5f5);
}

.sdc-sandbox__tag--due {
    background: var(--sdc-accent, #e11d1d);
    border-color: var(--sdc-accent, #e11d1d);
    color: #fff;
}

.sdc-sandbox__add {
    display: flex;
    gap: 0.5rem;
    margin-bottom: 1rem;
}

.sdc-sandbox__input {
    flex: 1;
    min-width: 0;
    padding: 0.625rem 0.75rem;
    font-size: 0.875rem;
    border: 1px solid var(--border-light, #e5e5e5);
    border-radius: var(--border-radius-small, 2px);
    background: var(--background-secondary, #f5f5f5);
    font-family: inherit;
}

.sdc-sandbox__input:focus {
    outline: 2px solid var(--sdc-ink, #0a0a0a);
    outline-offset: 0;
}

.sdc-sandbox__add-btn {
    padding: 0.625rem 1rem;
    font-size: 0.6875rem;
    font-weight: 700;
    letter-spacing: 0.06em;
    text-transform: uppercase;
    background: var(--sdc-ink, #0a0a0a);
    color: #fff;
    border: none;
    border-radius: var(--border-radius-small, 2px);
    cursor: pointer;
    font-family: inherit;
}

.sdc-sandbox__footer {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 0.75rem;
    flex-wrap: wrap;
    padding-top: 0.75rem;
    border-top: 1px solid var(--border-light, #e5e5e5);
}

.sdc-sandbox__collab-label {
    font-size: 0.6875rem;
    font-weight: 600;
    color: var(--text-secondary, #525252);
}

.sdc-sandbox__avatars {
    display: flex;
    margin-left: 0.5rem;
}

.sdc-sandbox__avatar {
    width: 1.75rem;
    height: 1.75rem;
    border-radius: 50%;
    border: 2px solid #fff;
    margin-left: -0.5rem;
    background: linear-gradient(135deg, #d4d4d4, #a3a3a3);
    font-size: 0.625rem;
    display: flex;
    align-items: center;
    justify-content: center;
    color: #fff;
    font-weight: 700;
}

.sdc-sandbox__avatar:first-child {
    margin-left: 0;
}

.sdc-sandbox__remove {
    font-size: 0.6875rem;
    font-weight: 600;
    color: var(--sdc-accent, #e11d1d);
    background: none;
    border: none;
    cursor: pointer;
    font-family: inherit;
    padding: 0;
}

/* Features grid (maps to build-scale / learning paths) */
.sdc-features {
    padding-block: clamp(2.5rem, 6vw, 4rem);
    background: var(--background-primary, #fff);
}

.sdc-features__header {
    display: grid;
    grid-template-columns: 1fr;
    gap: 1.5rem;
    margin-bottom: clamp(2rem, 5vw, 3rem);
}

@media (min-width: 768px) {
    .sdc-features__header {
        grid-template-columns: 1fr 1fr;
        align-items: end;
    }
}

.sdc-features__eyebrow {
    display: block;
    font-size: 0.6875rem;
    font-weight: 700;
    letter-spacing: 0.12em;
    text-transform: uppercase;
    color: var(--sdc-accent, #e11d1d);
    margin-bottom: 0.75rem;
}

.sdc-features__title {
    margin: 0;
    font-size: clamp(1.75rem, 4vw, 2.5rem);
    font-weight: 800;
    letter-spacing: -0.03em;
    line-height: 1.1;
    color: var(--text-primary, #0a0a0a);
}

.sdc-features__lead {
    margin: 0;
    font-size: 1rem;
    line-height: 1.65;
    color: var(--text-secondary, #525252);
}

.sdc-features__grid {
    display: grid;
    grid-template-columns: 1fr;
    border: 1px solid var(--sdc-ink, #0a0a0a);
}

@media (min-width: 768px) {
    .sdc-features__grid {
        grid-template-columns: repeat(3, 1fr);
    }
}

.sdc-features__col {
    padding: clamp(1.25rem, 3vw, 2rem);
    border-bottom: 1px solid var(--sdc-ink, #0a0a0a);
}

@media (min-width: 768px) {
    .sdc-features__col {
        border-bottom: none;
        border-right: 1px solid var(--sdc-ink, #0a0a0a);
    }

    .sdc-features__col:last-child {
        border-right: none;
    }
}

.sdc-features__col:last-child {
    border-bottom: none;
}

.sdc-features__index {
    display: block;
    font-size: 0.6875rem;
    font-weight: 700;
    letter-spacing: 0.08em;
    text-transform: uppercase;
    color: var(--sdc-accent, #e11d1d);
    margin-bottom: 1rem;
}

.sdc-features__col-title {
    margin: 0 0 0.75rem;
    font-size: 1.25rem;
    font-weight: 700;
    color: var(--text-primary, #0a0a0a);
}

.sdc-features__col-text {
    margin: 0 0 1.5rem;
    font-size: 0.9375rem;
    line-height: 1.6;
    color: var(--text-secondary, #525252);
}

.sdc-features__bar {
    display: block;
    width: 2.5rem;
    height: 4px;
    background: var(--sdc-ink, #0a0a0a);
}

/* Responsive */
@media (max-width: 640px) {
    .sdc-stats {
        grid-template-columns: 1fr;
        gap: 1.25rem;
    }

    .sdc-hero__actions {
        flex-direction: column;
        width: 100%;
    }

    .sdc-hero__cta {
        width: 100%;
    }
}

/* Non-Swiss skins: hide shell-only blocks */
body:not(.sdc-layout-swiss) .sdc-hero-zone,
body:not(.sdc-layout-swiss) .sdc-stats,
body:not(.sdc-layout-swiss) .sdc-sandbox,
body:not(.sdc-layout-swiss) .sdc-features--standalone {
    display: none;
}