/* ==========================================================================
   NASA Page · "Mars dust storm" theme
   Every colour lives here. Change the palette in one minute.
   ========================================================================== */

:root {
    /* Brand palette (the 5 original colours) */
    --rust-900: #3b2f2f;   /* dark cocoa: dark bg / light text */
    --rust-850: #3c2f2f;   /* almost the same cocoa: dark input fields */
    --peach-200: #ffdab9;  /* Mars dust peach: light bg / dark text / glow */
    --rust-600: #6b4226;   /* rust brown: buttons, accents */
    --grey-400: #a9a9a9;   /* regolith grey: secondary text in dark mode */

    /* Tints made from the palette */
    --peach-50: #fff1e4;   /* light card surface */
    --grey-700: #5c5c5c;   /* darker grey: secondary text in light mode (5.1:1) */
    --rust-800: #463837;   /* lighter cocoa: dark card surface */
    --white: #ffffff;
    --peach-300: #f5c49a;  /* warmer peach towards the horizon */
    --rust-950: #2a2020;   /* night sky above Mars */

    /* Light theme tokens (default) */
    --bg: var(--peach-200);
    --surface: var(--peach-50);
    --surface-glass: rgb(255 241 228 / 0.82);
    --field: var(--white);
    --text: var(--rust-900);
    --muted: var(--grey-700);
    --accent: var(--rust-600);
    --accent-soft: rgb(107 66 38 / 0.12);
    --border: rgb(59 47 47 / 0.14);
    --field-border: var(--rust-600);
    --btn-bg: var(--rust-600);
    --btn-text: var(--peach-200);
    --focus: var(--rust-600);
    --shadow: 0 0.6rem 1.6rem rgb(107 66 38 / 0.22);
    --shadow-lift: 0 1rem 2.4rem rgb(107 66 38 / 0.3);
    --hud-bg: rgb(59 47 47 / 0.78);
    --hud-text: var(--peach-200);
    --ripple: rgb(255 218 185 / 0.45);

    /* Live background */
    --sky-top: var(--peach-200);
    --sky-bottom: var(--peach-300);
    --glow-sun: rgb(255 255 255 / 0.75);
    --glow-dust: rgb(107 66 38 / 0.28);
    --dust: var(--rust-600);
    --dust-opacity: 0.35;
    --star-opacity: 0;
    --tracks: rgb(107 66 38 / 0.06);

    /* Type */
    --font-display: "Orbitron", "Segoe UI", sans-serif;
    --font-body: "Inter", system-ui, -apple-system, "Segoe UI", sans-serif;
    --font-mono: "Space Mono", ui-monospace, "Consolas", monospace;

    /* Shape: "mission panel" corners, big + small */
    --r-big: 1.5rem;
    --r-small: 0.35rem;
    --panel-shape: var(--r-big) var(--r-small) var(--r-big) var(--r-small);
    --btn-shape: 0.9rem 0.25rem 0.9rem 0.25rem;

    color-scheme: light;
}

/* Dark theme: same palette, night on Mars */
@media (prefers-color-scheme: dark) {
    :root:not([data-theme="light"]) {
        --bg: var(--rust-900);
        --surface: var(--rust-800);
        --surface-glass: rgb(70 56 55 / 0.84);
        --field: var(--rust-850);
        --text: var(--peach-200);
        --muted: var(--grey-400);
        --accent: var(--peach-200);
        --accent-soft: rgb(255 218 185 / 0.1);
        --border: rgb(255 218 185 / 0.14);
        --field-border: var(--grey-400);
        --btn-bg: var(--peach-200);
        --btn-text: var(--rust-900);
        --focus: var(--peach-200);
        --shadow: 0 0.6rem 1.6rem rgb(0 0 0 / 0.35);
        --shadow-lift: 0 1rem 2.4rem rgb(107 66 38 / 0.55);
        --hud-bg: rgb(59 47 47 / 0.82);
        --ripple: rgb(107 66 38 / 0.4);
        --sky-top: var(--rust-950);
        --sky-bottom: var(--rust-900);
        --glow-sun: rgb(255 218 185 / 0.16);
        --glow-dust: rgb(107 66 38 / 0.6);
        --dust: var(--peach-200);
        --dust-opacity: 0.55;
        --star-opacity: 1;
        --tracks: rgb(255 218 185 / 0.035);
        color-scheme: dark;
    }
}

:root[data-theme="dark"] {
    --bg: var(--rust-900);
    --surface: var(--rust-800);
    --surface-glass: rgb(70 56 55 / 0.84);
    --field: var(--rust-850);
    --text: var(--peach-200);
    --muted: var(--grey-400);
    --accent: var(--peach-200);
    --accent-soft: rgb(255 218 185 / 0.1);
    --border: rgb(255 218 185 / 0.14);
    --field-border: var(--grey-400);
    --btn-bg: var(--peach-200);
    --btn-text: var(--rust-900);
    --focus: var(--peach-200);
    --shadow: 0 0.6rem 1.6rem rgb(0 0 0 / 0.35);
    --shadow-lift: 0 1rem 2.4rem rgb(107 66 38 / 0.55);
    --hud-bg: rgb(59 47 47 / 0.82);
    --ripple: rgb(107 66 38 / 0.4);
    --sky-top: var(--rust-950);
    --sky-bottom: var(--rust-900);
    --glow-sun: rgb(255 218 185 / 0.16);
    --glow-dust: rgb(107 66 38 / 0.6);
    --dust: var(--peach-200);
    --dust-opacity: 0.55;
    --star-opacity: 1;
    --tracks: rgb(255 218 185 / 0.035);
    color-scheme: dark;
}

/* ==========================================================================
   Base
   ========================================================================== */

*,
*::before,
*::after {
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
    scroll-padding-top: 5rem;
}

body {
    margin: 0;
    min-height: 100vh;
    background: var(--bg);
    color: var(--text);
    font-family: var(--font-body);
    font-size: 1rem;
    line-height: 1.6;
    overflow-x: hidden;
    transition: background-color 0.4s ease, color 0.4s ease;
}

img {
    display: block;
    max-width: 100%;
    height: auto;
}

h1,
h2,
h3 {
    font-family: var(--font-display);
    line-height: 1.15;
    margin: 0;
}

:focus-visible {
    outline: 3px solid var(--focus);
    outline-offset: 3px;
    border-radius: 0.25rem;
}

main:focus {
    outline: none;
}

.skip-link {
    position: fixed;
    top: 0.75rem;
    left: 0.75rem;
    z-index: 100;
    padding: 0.6rem 1rem;
    background: var(--btn-bg);
    color: var(--btn-text);
    font-weight: 600;
    border-radius: var(--btn-shape);
    transform: translateY(-200%);
    transition: transform 0.2s ease;
}

.skip-link:focus {
    transform: translateY(0);
}

.link {
    color: var(--accent);
    font-weight: 600;
    text-underline-offset: 0.2em;
}

.link:hover {
    text-decoration-thickness: 2px;
}

.meta {
    font-family: var(--font-mono);
    font-size: 0.85rem;
    color: var(--muted);
    margin: 0;
}

.eyebrow,
.panel__tag {
    font-family: var(--font-mono);
    font-size: 0.8rem;
    letter-spacing: 0.14em;
    text-transform: uppercase;
    color: var(--muted);
    margin: 0 0 0.75rem;
}

/* ==========================================================================
   Live background: Mars dust storm
   ========================================================================== */

.sky {
    position: fixed;
    inset: 0;
    z-index: -1;
    overflow: hidden;
    pointer-events: none;
    background: linear-gradient(to bottom, var(--sky-top), var(--sky-bottom));
    transition: background 0.4s ease;
}

.sky__glow {
    position: absolute;
    border-radius: 50%;
    filter: blur(70px);
    will-change: transform;
}

.sky__glow--sun {
    width: 42vmax;
    height: 42vmax;
    top: -12vmax;
    right: -8vmax;
    background: var(--glow-sun);
    animation: glow-drift-a 28s ease-in-out infinite alternate;
}

.sky__glow--dust {
    width: 60vmax;
    height: 38vmax;
    bottom: -14vmax;
    left: -14vmax;
    background: var(--glow-dust);
    animation: glow-drift-b 36s ease-in-out infinite alternate;
}

/* Soft rover-track texture near the ground */
.sky__tracks {
    position: absolute;
    inset: auto 0 0 0;
    height: 45vh;
    background:
        repeating-linear-gradient(100deg, transparent 0 22px, var(--tracks) 22px 26px),
        repeating-linear-gradient(80deg, transparent 0 40px, var(--tracks) 40px 42px);
    mask-image: linear-gradient(to top, black, transparent);
}

.sky__particles {
    position: absolute;
    inset: 0;
}

/* Dust grain: carried across the screen by the wind */
.dust {
    position: absolute;
    left: 0;
    top: var(--y);
    width: var(--size);
    height: var(--size);
    border-radius: 50%;
    background: var(--dust);
    opacity: 0;
    will-change: transform, opacity;
    animation: dust-wind var(--duration) linear var(--delay) infinite;
}

.dust--blur {
    filter: blur(1.5px);
}

/* Star: only visible at night (dark theme) */
.star {
    position: absolute;
    left: var(--x);
    top: var(--y);
    width: var(--size);
    height: var(--size);
    border-radius: 50%;
    background: var(--peach-200);
    opacity: 0;
    animation: twinkle var(--duration) ease-in-out var(--delay) infinite;
}

@keyframes dust-wind {
    0% {
        transform: translate3d(-5vw, 0, 0);
        opacity: 0;
    }
    10% {
        opacity: var(--dust-opacity);
    }
    50% {
        transform: translate3d(50vw, var(--wobble), 0);
    }
    90% {
        opacity: var(--dust-opacity);
    }
    100% {
        transform: translate3d(105vw, var(--fall), 0);
        opacity: 0;
    }
}

@keyframes twinkle {
    0%,
    100% {
        opacity: 0;
    }
    50% {
        opacity: calc(var(--star-opacity) * var(--peak));
    }
}

@keyframes glow-drift-a {
    to {
        transform: translate3d(-8vw, 6vh, 0) scale(1.12);
    }
}

@keyframes glow-drift-b {
    to {
        transform: translate3d(10vw, -5vh, 0) scale(1.18);
    }
}

/* ==========================================================================
   Top bar
   ========================================================================== */

.topbar {
    position: sticky;
    top: 0;
    z-index: 10;
    display: flex;
    align-items: center;
    gap: 1.5rem;
    padding: 0.75rem clamp(1rem, 4vw, 3rem);
    background: var(--surface-glass);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid var(--border);
}

.brand {
    display: inline-flex;
    align-items: center;
    gap: 0.6rem;
    color: var(--text);
    text-decoration: none;
    font-family: var(--font-display);
    font-weight: 800;
    font-size: 1.1rem;
    letter-spacing: 0.06em;
}

.brand__logo {
    transition: transform 0.6s cubic-bezier(0.34, 1.56, 0.64, 1);
}

.brand:hover .brand__logo {
    transform: rotate(-25deg) scale(1.08);
}

.brand__planet {
    fill: var(--rust-600);
}

.brand__ring {
    fill: none;
    stroke: var(--text);
    stroke-width: 1.6;
}

.brand__crater {
    fill: var(--peach-200);
    opacity: 0.6;
}

.brand__dot {
    color: var(--accent);
    margin: 0 0.1em;
}

.topbar__nav {
    display: flex;
    gap: 1.25rem;
    margin-left: auto;
}

.topbar__nav a {
    position: relative;
    color: var(--text);
    text-decoration: none;
    font-weight: 500;
    font-size: 0.95rem;
}

.topbar__nav a::after {
    content: "";
    position: absolute;
    left: 0;
    right: 0;
    bottom: -0.2rem;
    height: 2px;
    background: var(--accent);
    transform: scaleX(0);
    transform-origin: left;
    transition: transform 0.25s ease;
}

.topbar__nav a:hover::after {
    transform: scaleX(1);
}

.theme-toggle {
    display: grid;
    place-items: center;
    width: 2.75rem;
    height: 2.75rem;
    padding: 0;
    border: 1px solid var(--field-border);
    border-radius: 50%;
    background: var(--surface);
    color: var(--text);
    cursor: pointer;
    transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.theme-toggle:hover {
    transform: translateY(-2px) rotate(15deg);
    box-shadow: var(--shadow);
}

.theme-toggle svg {
    grid-area: 1 / 1;
    fill: none;
    stroke: currentColor;
    stroke-width: 1.8;
    stroke-linecap: round;
    transition: transform 0.4s ease, opacity 0.3s ease;
}

.theme-toggle__moon {
    opacity: 0;
    transform: rotate(-90deg) scale(0.5);
}

:root[data-theme="dark"] .theme-toggle__sun {
    opacity: 0;
    transform: rotate(90deg) scale(0.5);
}

:root[data-theme="dark"] .theme-toggle__moon {
    opacity: 1;
    transform: none;
}

@media (prefers-color-scheme: dark) {
    :root:not([data-theme="light"]) .theme-toggle__sun {
        opacity: 0;
        transform: rotate(90deg) scale(0.5);
    }

    :root:not([data-theme="light"]) .theme-toggle__moon {
        opacity: 1;
        transform: none;
    }
}

/* ==========================================================================
   Layout
   ========================================================================== */

main {
    width: min(72rem, 100% - 2rem);
    margin: 0 auto;
    padding-bottom: 4rem;
}

.hero {
    padding: clamp(3rem, 10vw, 7rem) 0 3rem;
}

.hero__title {
    font-size: clamp(2.2rem, 7vw, 4.75rem);
    font-weight: 800;
    letter-spacing: 0.01em;
    max-width: 14ch;
}

.hero__lead {
    max-width: 38rem;
    margin: 1.25rem 0 2rem;
    font-size: 1.125rem;
    color: var(--text);
}

.hero__actions {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    gap: 1rem 1.5rem;
}

.status {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    margin: 0;
    padding: 0.4rem 0.9rem;
    font-family: var(--font-mono);
    font-size: 0.8rem;
    color: var(--text);
    background: var(--surface-glass);
    border: 1px solid var(--border);
    border-radius: 999px;
}

.status__dot {
    width: 0.6rem;
    height: 0.6rem;
    border-radius: 50%;
    background: var(--muted);
}

.status[data-state="live"] .status__dot {
    background: var(--accent);
    animation: pulse 1.8s ease-out infinite;
}

.status[data-state="demo"] .status__dot {
    background: transparent;
    border: 2px solid var(--accent);
}

@keyframes pulse {
    0% {
        box-shadow: 0 0 0 0 var(--accent-soft), 0 0 0 0 var(--accent);
    }
    100% {
        box-shadow: 0 0 0 0.6rem transparent, 0 0 0 0 transparent;
    }
}

/* Stats */
.stats {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 1rem;
    margin: 3rem 0 0;
    padding: 0;
    list-style: none;
}

.stat {
    padding: 1.25rem 1.25rem 1rem;
    background: var(--surface-glass);
    border: 1px solid var(--border);
    border-left: 4px solid var(--accent);
    border-radius: var(--panel-shape);
    backdrop-filter: blur(6px);
}

.stat__value {
    display: block;
    font-family: var(--font-display);
    font-weight: 800;
    font-size: clamp(1.6rem, 4vw, 2.4rem);
    font-variant-numeric: tabular-nums;
}

.stat__label {
    font-size: 0.9rem;
    color: var(--muted);
}

/* Panels ("mission panels") */
.panel {
    position: relative;
    margin-top: 2rem;
    padding: clamp(1.25rem, 3vw, 2rem);
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: var(--panel-shape);
    box-shadow: var(--shadow);
    transition: transform 0.3s ease, box-shadow 0.3s ease, background-color 0.4s ease;
}

.panel:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-lift);
}

/* Small notch in the top-right corner, like a mission control plate */
.panel::before {
    content: "";
    position: absolute;
    top: 1.1rem;
    right: 1.1rem;
    width: 2.2rem;
    height: 0.35rem;
    border-radius: 999px;
    background: repeating-linear-gradient(90deg, var(--accent) 0 0.35rem, transparent 0.35rem 0.6rem);
    opacity: 0.6;
}

.panel__head {
    margin-bottom: 1.25rem;
}

.panel__title {
    font-size: clamp(1.25rem, 3vw, 1.75rem);
    font-weight: 600;
}

.duo {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 0 2rem;
}

/* Forms */
.controls {
    display: flex;
    flex-wrap: wrap;
    align-items: flex-end;
    gap: 0.75rem;
    margin-bottom: 1.25rem;
}

.field {
    display: flex;
    flex-direction: column;
    gap: 0.3rem;
    min-width: 0;
}

.field--small {
    width: 7.5rem;
}

.field--grow {
    flex: 1 1 12rem;
}

.field label {
    font-size: 0.85rem;
    font-weight: 600;
}

.field__hint {
    font-weight: 400;
    color: var(--muted);
}

.field input,
.field select {
    width: 100%;
    min-height: 2.75rem;
    padding: 0.5rem 0.75rem;
    font: inherit;
    color: var(--text);
    background: var(--field);
    border: 1.5px solid var(--field-border);
    border-radius: 0.6rem 0.2rem 0.6rem 0.2rem;
}

.field input::placeholder {
    color: var(--muted);
}

/* Buttons */
.btn {
    position: relative;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 0.55rem;
    min-height: 2.75rem;
    padding: 0.6rem 1.2rem;
    overflow: hidden;
    font: 600 0.95rem/1 var(--font-body);
    text-decoration: none;
    border: 1.5px solid var(--btn-bg);
    border-radius: var(--btn-shape);
    cursor: pointer;
    box-shadow: var(--shadow);
    transition: transform 0.18s ease, box-shadow 0.18s ease, background-color 0.3s ease;
}

.btn--primary {
    background: var(--btn-bg);
    color: var(--btn-text);
}

.btn--ghost {
    background: transparent;
    color: var(--text);
    border-color: var(--field-border);
    box-shadow: none;
}

.btn:hover {
    transform: translateY(-3px);
    box-shadow: var(--shadow-lift);
}

.btn:active {
    transform: translateY(1px);
    box-shadow: none;
}

.btn[disabled] {
    cursor: progress;
    opacity: 0.8;
}

.btn__icon {
    flex: none;
    fill: none;
    stroke: currentColor;
    stroke-width: 1.8;
    stroke-linecap: round;
    stroke-linejoin: round;
    transition: transform 0.5s cubic-bezier(0.34, 1.56, 0.64, 1);
}

/* Theme-matching micro effects */
.btn:hover .icon-wheel,
.btn.is-loading .icon-wheel {
    animation: spin 0.9s linear infinite;
}

.btn:hover .icon-rocket {
    transform: translate(3px, -3px) rotate(-8deg);
}

.btn.is-loading .icon-rocket {
    animation: lift-off 0.8s ease-in infinite;
}

.btn:hover .icon-spark,
.btn.is-loading .icon-spark {
    transform: rotate(90deg) scale(1.15);
}

.btn:hover .icon-dice {
    transform: rotate(180deg);
}

.btn:hover .icon-telescope {
    transform: rotate(-12deg);
}

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

@keyframes lift-off {
    0% {
        transform: translate(0, 0);
        opacity: 1;
    }
    70% {
        transform: translate(10px, -10px);
        opacity: 0;
    }
    71% {
        transform: translate(-8px, 8px);
        opacity: 0;
    }
    100% {
        transform: translate(0, 0);
        opacity: 1;
    }
}

.ripple {
    position: absolute;
    width: 12px;
    height: 12px;
    margin: -6px 0 0 -6px;
    border-radius: 50%;
    background: var(--ripple);
    pointer-events: none;
    animation: ripple 0.6s ease-out forwards;
}

@keyframes ripple {
    from {
        transform: scale(0);
        opacity: 1;
    }
    to {
        transform: scale(28);
        opacity: 0;
    }
}

/* Viewfinder: image frame with rover-camera corner brackets */
.viewfinder {
    position: relative;
    margin: 0;
}

.viewfinder img {
    width: 100%;
    aspect-ratio: 16 / 10;
    object-fit: cover;
    background: var(--accent-soft);
    border-radius: 1rem 0.25rem 1rem 0.25rem;
    transition: opacity 0.4s ease, filter 0.4s ease;
}

.viewfinder.is-loading img {
    opacity: 0.35;
    filter: sepia(0.6) blur(2px);
}

.viewfinder::before {
    content: attr(data-hud);
    position: absolute;
    top: 0.75rem;
    left: 0.75rem;
    z-index: 1;
    padding: 0.2rem 0.55rem;
    font-family: var(--font-mono);
    font-size: 0.7rem;
    letter-spacing: 0.12em;
    color: var(--hud-text);
    background: var(--hud-bg);
    border-radius: 0.3rem;
}

.viewfinder::after {
    content: "";
    position: absolute;
    inset: 0.5rem 0.5rem auto auto;
    width: 1.5rem;
    height: 1.5rem;
    border-top: 2px solid var(--peach-200);
    border-right: 2px solid var(--peach-200);
    border-radius: 0 0.3rem 0 0;
    opacity: 0.85;
}

.viewfinder figcaption {
    margin-top: 0.75rem;
}

/* APOD layout */
.apod {
    display: grid;
    grid-template-columns: minmax(0, 1.4fr) minmax(0, 1fr);
    gap: 1.75rem;
    align-items: start;
}

.apod__media img,
.apod__media iframe {
    aspect-ratio: 4 / 3;
}

.apod__media iframe {
    display: block;
    width: 100%;
    border: 0;
    border-radius: 1rem 0.25rem 1rem 0.25rem;
}

.apod__heading {
    font-size: 1.35rem;
    font-weight: 600;
    margin-bottom: 0.4rem;
}

.apod__explanation {
    max-height: 18rem;
    overflow-y: auto;
    margin: 1rem 0;
    padding-right: 0.5rem;
    color: var(--text);
}

/* Footer */
.footer {
    padding: 2rem 1rem 3rem;
    text-align: center;
    background: var(--surface-glass);
    border-top: 1px solid var(--border);
}

.footer p {
    margin: 0.3rem 0;
}

/* Scroll reveal (only when JS is running) */
.js .reveal {
    opacity: 0;
    transform: translateY(24px);
    transition: opacity 0.7s ease, transform 0.7s ease;
}

.js .reveal.is-visible {
    opacity: 1;
    transform: none;
}

/* ==========================================================================
   Responsive
   ========================================================================== */

@media (max-width: 860px) {
    .apod,
    .duo {
        grid-template-columns: 1fr;
    }

    .topbar__nav {
        display: none;
    }

    .theme-toggle {
        margin-left: auto;
    }
}

@media (max-width: 560px) {
    .stats {
        grid-template-columns: 1fr;
    }

    .controls .btn {
        flex: 1 1 auto;
    }

    .field:not(.field--small) {
        flex: 1 1 100%;
    }

    .field--small {
        flex: 1 1 6rem;
    }
}

/* ==========================================================================
   Reduced motion: no particles, no movement, static glow stays
   ========================================================================== */

@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;
    }

    .sky__particles {
        display: none;
    }

    .js .reveal {
        opacity: 1;
        transform: none;
    }
}