:root {
    --bg-color: #000000;
    --card-bg: #15171e;
    --card-bg-active: #1f222b;
    --accent: #ffae00;
    --accent-dim: #996900;
    --text-main: #e0e0e0;
    --text-muted: #757a85;
    --border-color: #2f323b;
    --font-stack: "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
    --ease-out-quint: cubic-bezier(0.23, 1, 0.32, 1);
}

body.physics-page {
    background-color: var(--bg-color);
    color: var(--text-main);
    font-family: var(--font-stack);
    overflow: hidden;
    height: 100vh;
    width: 100vw;
}

html.physics-page {
    height: 100%;
    overflow-x: hidden !important;
    overflow-y: hidden !important;
}

html.physics-inline-open {
    height: 100%;
    overflow-x: hidden !important;
    overflow-y: hidden !important;
}

body.physics-inline-open {
    overflow: hidden;
}

.course-view.physics-inline-active {
    padding-bottom: 0;
}

.course-view.physics-inline-active #course-content #app-container,
.course-view.physics-inline-active .course-content-shell #app-container {
    padding-bottom: 0;
}

body.physics-page #app-container,
body.physics-page .lecture-track-container {
    padding-bottom: 0;
}

.course-content-shell.physics-inline {
    background-color: var(--bg-color);
    color: var(--text-main);
    font-family: var(--font-stack);
    overflow: visible;
}

:where(body.physics-page *) {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
    user-select: none;
}

:where(#app-container, #app-container *) {
    box-sizing: border-box;
}

#app-container {
    color: var(--text-main);
    font-family: var(--font-stack);
}

:where(#app-container *) {
    margin: 0;
    padding: 0;
    user-select: none;
}

.screen-vignette,
.noise-overlay,
.bg-grid-plane {
    display: none;
}

#app-container {
    position: relative;
    width: 100%;
    height: 100%;
    z-index: 10;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: flex-start;
    padding: 2rem 1.5rem 3rem;
    overflow: visible;
    max-width: 1400px;
    margin: 0 auto;
}

/* When injected into the home inline viewer, center and lift the block */
#course-content #app-container,
.course-content-shell #app-container {
    width: 100%;
    max-width: 1100px;
    margin: -180px auto 0;
    padding: 0;
    transform: none;
    align-items: center;
}

/* Hard center alignment when embedded in the inline viewer */
.course-content-shell #app-container .ui-layer {
    width: 100%;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: flex-start;
}

.course-content-shell #app-container .mission-carousel-stage {
    width: 100%;
    max-width: 1100px;
    margin: 0 auto;
}

.course-content-shell #app-container .lecture-track-container {
    width: 100%;
    max-width: 1100px;
    margin: 0 auto;
}

/* Lift and center the back arrow in the inline viewer */
.course-content-shell #course-back {
    top: 90px;
    left: 50%;
    transform: translateX(-50%);
}

.ui-layer {
    width: 100%;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 1rem;
}

.mission-carousel-stage {
    position: relative;
    width: min(92vw, 1400px);
    max-width: 1400px;
    min-height: 470px;
    display: flex;
    align-items: center;
    justify-content: center;
    margin-top: 2.4rem;
    top: 14px;
    transform: translateY(18px);
    overflow: visible;
    margin-left: auto;
    margin-right: auto;
}

.card-container {
    position: relative;
    width: 100%;
    height: 100%;
    padding-top: 18px;
}

.course-rail {
    position: relative;
    width: 100%;
    height: 100%;
    padding: 12px 8px 6px;
}

.rail-top,
.rail-heading,
.rail-title,
.rail-meta,
.rail-controls,
.rail-btn {
    display: none;
}

.deck-window {
    position: relative;
    width: 100%;
    overflow: visible;
    min-height: 420px;
}

.deck-window.is-locked {
    pointer-events: none;
}

.course-deck {
    --card-width: min(26vw, 320px);
    --card-height: calc(var(--card-width) * 1.35);
    position: relative;
    width: 100%;
    height: calc(var(--card-height) + 30px);
    perspective: 1200px;
    transform-style: preserve-3d;
    transition: transform 0.7s var(--ease-out-quint);
    will-change: transform, opacity;
}

.course-card {
    position: relative;
    position: absolute;
    left: 50%;
    top: 0;
    width: var(--card-width);
    min-width: 230px;
    height: var(--card-height);
    aspect-ratio: 0.707;
    background: #0b0b0b;
    border: 1px solid #1c1c1c;
    border-radius: 14px;
    padding: 18px 18px 18px;
    overflow: hidden;
    box-shadow: 0 14px 36px rgba(0, 0, 0, 0.55);
    transition: transform 0.65s var(--ease-out-quint), box-shadow 0.45s, border-color 0.4s, opacity 0.4s, background 0.4s;
    cursor: pointer;
    color: var(--text-main);
    backface-visibility: hidden;
    transform: var(--pose);
}

.course-card::after {
    content: "";
    position: absolute;
    inset: -1px;
    border-radius: 14px;
    background: none;
    opacity: 0;
    transition: opacity 0.3s;
    pointer-events: none;
}

.course-card:hover {
    border-color: var(--accent);
    background: #0f0f0f;
    box-shadow: 0 14px 36px rgba(0, 0, 0, 0.55);
    transform: var(--pose) translateY(-4px);
}

.course-card:hover::after {
    opacity: 0;
}

.course-card.active {
    border-color: var(--accent);
    background: #0e0e0e;
    box-shadow: 0 22px 60px rgba(0, 0, 0, 0.8), 0 0 0 1px rgba(255, 174, 0, 0.35);
}

.card-chip {
    font-size: 0.7rem;
    letter-spacing: 1.5px;
    color: var(--accent);
    margin-bottom: 10px;
    font-weight: 400;
    text-transform: uppercase;
    font-family: var(--font-stack);
}

.card-heading {
    font-size: 1.6rem;
    font-weight: 800;
    line-height: 1.2;
    color: var(--text-main);
    margin-bottom: 6px;
    text-transform: uppercase;
}

.card-sub {
    font-size: 0.9rem;
    color: var(--text-muted);
    margin-bottom: 12px;
}

.card-visual {
    width: 100%;
    aspect-ratio: 1 / 1;
    border: none;
    border-radius: 12px;
    background: transparent;
    margin-bottom: 10px;
    position: relative;
    overflow: hidden;
}

.card-visual.has-image {
    background-color: transparent;
    background-position: center;
    background-size: contain;
    background-repeat: no-repeat;
}

.card-visual::before {
    content: "";
    position: absolute;
    inset: -40%;
    background: none;
    opacity: 0;
    transform: none;
}

@media (max-width: 900px) {
    .mission-carousel-stage {
        min-height: 430px;
    }

    .deck-window {
        min-height: 390px;
    }

    .course-deck {
        --card-width: min(70vw, 260px);
        --card-height: calc(var(--card-width) * 1.35);
        height: calc(var(--card-height) + 24px);
    }
}

@media (max-width: 520px) {
    .mission-carousel-stage {
        min-height: 400px;
    }

    .deck-window {
        min-height: 360px;
    }

    .course-deck {
        height: calc(var(--card-height) + 16px);
    }
}

.lecture-track-container {
    width: min(90vw, 1400px);
    max-width: 1400px;
    margin: 0 auto;
    display: flex;
    flex-direction: column;
    align-items: stretch;
    justify-content: flex-start;
    padding-top: 0.6rem;
    padding-bottom: 2rem;
    position: relative;
}

.track-label {
    font-size: 0.6rem;
    letter-spacing: 3px;
    color: var(--accent);
    margin-bottom: 1rem;
    text-transform: uppercase;
    opacity: 0.9;
    padding: 0 2px;
    display: inline-block;
    align-self: center;
}

.course-lock-note {
    position: absolute;
    top: 0;
    left: 50%;
    z-index: 5;
    margin: 0;
    max-width: 640px;
    width: min(90vw, 640px);
    padding: 12px 16px;
    border-radius: 12px;
    border: 1px dashed #2a2a2a;
    background: rgba(10, 10, 10, 0.65);
    text-align: center;
    pointer-events: none;
    transform: translate(-50%, -90%);
}

.course-lock-message {
    display: block;
    font-size: 0.85rem;
    color: var(--text-muted);
    line-height: 1.4;
}

.lecture-track {
    display: grid;
    grid-template-columns: repeat(10, minmax(150px, 1fr));
    gap: 18px;
    width: 100%;
    position: relative;
    align-items: stretch;
    justify-items: stretch;
    justify-content: center;
}

@media (max-width: 1200px) {
    .lecture-track {
        grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
    }
}

.tech-module {
    position: relative;
    width: auto;
    max-width: 100%;
    min-height: 150px;
    height: auto;
    background: #0b0b0b;
    border: 1px solid #1c1c1c;
    border-radius: 10px;
    display: flex;
    flex-direction: column;
    justify-content: space-between;
    padding: 16px 18px;
    cursor: pointer;
    transition: transform 0.2s cubic-bezier(0.23, 1, 0.32, 1), border-color 0.2s, background 0.2s;
    opacity: 0;
    transform: translateY(10px);
    overflow: hidden;
    box-shadow: none;
}

.tech-module.visible {
    animation: moduleReveal 0.4s forwards;
}

.tech-module:hover {
    background: #0f0f0f;
    border-color: var(--accent);
    transform: translateY(-4px);
}

.tech-module:hover .status-dot {
    background: var(--accent);
}

.tech-module:hover .module-action {
    opacity: 1;
}

.tech-module:active {
    transform: translateY(-1px);
}

.module-corner {
    display: none;
}

.module-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 8px;
}

.module-id {
    font-size: 0.55rem;
    color: #8a8a8a;
    letter-spacing: 1px;
    font-weight: 700;
}

.status-dot {
    width: 6px;
    height: 6px;
    background: #444;
    border-radius: 50%;
    transition: background 0.3s;
}

.module-content {
    display: flex;
    flex-direction: column;
    gap: 4px;
}

.module-code {
    font-family: monospace;
    font-size: 0.65rem;
    color: var(--accent-dim);
}

.module-title {
    font-size: 1rem;
    font-weight: 800;
    color: var(--text-main);
    line-height: 1.2;
}

.module-footer {
    display: flex;
    justify-content: space-between;
    align-items: flex-end;
    margin-top: auto;
    font-size: 0.7rem;
    color: var(--text-muted);
    padding-top: 10px;
    border-top: 1px solid #141414;
}

.module-action {
    display: none;
}

@keyframes moduleReveal {
    to {
        opacity: 1;
        transform: translateY(0) scale(1);
    }
}

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

@keyframes fadeIn {
    to {
        opacity: 1;
    }
}

/* Module detail modal */
.module-modal-overlay {
    display: none;
    position: fixed;
    inset: 0;
    background: rgba(0, 0, 0, 0.82);
    backdrop-filter: blur(2px);
    z-index: 3200;
    align-items: center;
    justify-content: center;
    padding: 28px 20px;
    color: var(--text-main);
    font-family: var(--font-stack);
}

.module-modal-overlay,
.module-modal-overlay * {
    box-sizing: border-box;
}

.module-modal-overlay * {
    user-select: none;
}

.module-modal-overlay.visible {
    display: flex;
    animation: moduleModalFadeIn 0.3s ease-in-out forwards;
}

.module-modal-overlay.closing {
    animation: moduleModalFadeOut 0.3s ease-in-out forwards;
}

.module-modal-card {
    position: relative;
    width: min(760px, 88vw);
    background: #0b0b0b;
    border: 1px solid #1c1c1c;
    border-radius: 16px;
    box-shadow: none;
    padding: 20px 20px 20px 20px;
    animation: moduleModalPopOut 0.4s var(--ease-out-quint);
}

.module-modal-overlay.closing .module-modal-card {
    animation: moduleModalPopIn 0.3s ease-in forwards;
}

.module-modal-close {
    position: absolute;
    top: 14px;
    right: 14px;
    width: 38px;
    height: 38px;
    border-radius: 10px;
    border: 1px solid #1c1c1c;
    background: #0b0b0b;
    color: #c9c9c9;
    cursor: pointer;
    font-size: 1.2rem;
    line-height: 1;
    transition: border-color 0.2s ease, color 0.2s ease, transform 0.2s ease;
}

.module-modal-close:hover {
    color: var(--accent);
    border-color: var(--accent);
    transform: translateY(-1px);
}

.module-modal-content {
    display: grid;
    grid-template-columns: 1fr 1.15fr;
    gap: 20px;
    align-items: stretch;
}

.module-modal-media {
    background: transparent;
    border: none;
    border-radius: 14px;
    padding: 0;
    display: flex;
    align-items: stretch;
    justify-content: stretch;
}

.module-media-placeholder {
    width: 100%;
    aspect-ratio: 1 / 1;
    border-radius: 12px;
    border: 1px dashed #1c1c1c;
    background: #0b0b0b;
    box-shadow: none;
}

.module-modal-info {
    display: flex;
    flex-direction: column;
    gap: 10px;
    min-height: 100%;
}

.module-modal-difficulty {
    font-size: 0.75rem;
    letter-spacing: 2.4px;
    color: var(--accent);
    font-weight: 500;
    text-transform: uppercase;
}

.module-modal-title {
    font-size: 1.85rem;
    font-weight: 800;
    color: var(--text-main);
    line-height: 1.2;
}

.module-modal-description {
    font-size: 0.98rem;
    color: var(--text-muted);
    line-height: 1.6;
    margin-top: 4px;
}

.module-modal-actions {
    margin-top: auto;
    display: flex;
    justify-content: flex-end;
}

.module-initiate-btn {
    background: var(--accent);
    color: #0b0b0b;
    border: none;
    border-radius: 12px;
    padding: 12px 20px;
    font-weight: 800;
    letter-spacing: 1.2px;
    cursor: pointer;
    box-shadow: none;
    transition: background-color 0.1s ease;
}

.module-initiate-btn:hover {
    background: #ffd34d;
}

.module-initiate-btn:active {
    background: var(--accent-dim);
}

@media (max-width: 860px) {
    .module-modal-content {
        grid-template-columns: 1fr;
    }

    .module-modal-card {
        padding: 20px 18px 20px 18px;
    }

    .module-modal-close {
        top: 10px;
        right: 10px;
    }
}

@keyframes moduleModalFadeIn {
    from {
        opacity: 0;
    }
    to {
        opacity: 1;
    }
}

@keyframes moduleModalFadeOut {
    from {
        opacity: 1;
    }
    to {
        opacity: 0;
    }
}

@keyframes moduleModalPopOut {
    0% {
        opacity: 0;
        transform: scale(0.94) translateY(6px);
    }
    100% {
        opacity: 1;
        transform: scale(1) translateY(0);
    }
}

@keyframes moduleModalPopIn {
    0% {
        opacity: 1;
        transform: scale(1) translateY(0);
    }
    100% {
        opacity: 0;
        transform: scale(0.9) translateY(6px);
    }
}