@import url('https://fonts.googleapis.com/css2?family=Playfair+Display:wght@700&family=Noto+Sans+JP:wght@300;400&display=swap');

:root {
    /* Base styles */
    --font-heading: 'Playfair Display', serif;
    --font-body: 'Noto Sans JP', sans-serif;
    --transition-speed: 0.5s;

    /* Light Theme (Day) */
    --day-bg: #f0f4f8;
    --day-particle: rgba(255, 192, 203, 0.6);
    --day-text: #333;
    --day-panel-bg: rgba(255, 255, 255, 0.7);
    --day-accent: #87ceeb;
    --day-highlight: #ffb6c1;

    /* Dark Theme (Night) - Default */
    --night-bg: #0a0e1a;
    --night-particle: rgba(0, 255, 255, 0.6);
    --night-text: #e0e0e0;
    --night-panel-bg: rgba(10, 14, 26, 0.7);
    --night-accent: #00ffff;
    --night-highlight: #ff00ff;

    /* Progress Stage Colors */
    --stage-0-hue: 0; /* Default */
    --stage-1-hue: 30; /* Warm shift */
    --stage-2-hue: 60; /* Yellowish */
    --stage-3-hue: 120; /* Greenish */
    --stage-4-hue: 240; /* Purplish */
}

body {
    margin: 0;
    font-family: var(--font-body);
    overflow: hidden;
}

#canvas-wrapper {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: -1;
    background-color: var(--bg-color);
    filter: url(#goo);
    -webkit-filter: url(#goo);
    transition: background-color var(--transition-speed);
}

#background-canvas {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
}

body.day-theme {
    --bg-color: var(--day-bg);
    --particle-color: var(--day-particle);
    --text-color: var(--day-text);
    --panel-bg-color: var(--day-panel-bg);
    --accent-color: var(--day-accent);
    --highlight-color: var(--day-highlight);
}

body.night-theme {
    --bg-color: var(--night-bg);
    --particle-color: var(--night-particle);
    --text-color: var(--night-text);
    --panel-bg-color: var(--night-panel-bg);
    --accent-color: var(--night-accent);
    --highlight-color: var(--night-highlight);
}

/* Progress-based color shift */
body.stage-1 { filter: hue-rotate(var(--stage-1-hue)); }
body.stage-2 { filter: hue-rotate(var(--stage-2-hue)); }
body.stage-3 { filter: hue-rotate(var(--stage-3-hue)); }
body.stage-4 { filter: hue-rotate(var(--stage-4-hue)); }

/* --- Screens --- */
.screen {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    display: flex;
    justify-content: center;
    align-items: center;
    text-align: center;
    opacity: 0;
    visibility: hidden;
    transition: opacity var(--transition-speed), visibility var(--transition-speed);
    z-index: 10;
    backdrop-filter: blur(5px);
}

.screen.visible {
    opacity: 1;
    visibility: visible;
}

.screen-content {
    background: rgba(30, 30, 30, 0.3);
    backdrop-filter: blur(10px) saturate(120%);
    -webkit-backdrop-filter: blur(10px) saturate(120%);
    border: 1px solid rgba(255, 255, 255, 0.1);
    color: var(--text-color);
    padding: 40px;
    border-radius: 15px;
    box-shadow: 0 10px 30px rgba(0,0,0,0.2);
}

#main-app-screen {
    flex-direction: row;
    justify-content: flex-start;
    align-items: stretch;
}

/* --- Controls Panel --- */
#controls-panel {
    width: 350px;
    padding: 20px;
    box-sizing: border-box;
    margin: 20px;
    height: calc(100vh - 40px);
    
    /* Glass Effect */
    background: rgba(30, 30, 30, 0.25);
    backdrop-filter: blur(15px) saturate(150%);
    -webkit-backdrop-filter: blur(15px) saturate(150%);
    border: 1px solid rgba(255, 255, 255, 0.1);
    border-radius: 15px;

    color: var(--text-color);
    display: flex;
    flex-direction: column;
    gap: 20px;
    z-index: 5;
    transition: background-color var(--transition-speed), color var(--transition-speed);
}

body.day-theme #controls-panel, body.day-theme .screen-content {
    background: rgba(255, 255, 255, 0.3);
    border: 1px solid rgba(255, 255, 255, 0.4);
}

/* --- Typography & Buttons --- */
h1, h2 {
    font-family: var(--font-heading);
    color: var(--accent-color);
    font-size: 2em;
    text-shadow: 0 0 10px var(--accent-color);
}

button {
    font-family: var(--font-body);
    font-weight: bold;
    font-size: 1em;
    padding: 12px 24px;
    border-radius: 50px;
    border: 2px solid var(--accent-color);
    background-color: transparent;
    color: var(--accent-color);
    cursor: pointer;
    transition: background-color 0.3s, color 0.3s, transform 0.2s;
}

button:hover {
    background-color: var(--accent-color);
    color: var(--bg-color);
    box-shadow: 0 0 15px var(--accent-color);
    transform: translateY(-2px);
}

/* --- UI Elements --- */
#time-info, #progress-info {
    padding: 15px;
    background: rgba(0,0,0,0.2);
    border-radius: 10px;
}
#current-time {
    font-size: 2em;
    font-weight: bold;
    color: var(--highlight-color);
}
#timer { font-size: 1.2em; }
#counter { font-size: 1.2em; font-weight: bold; }
#comment-box { min-height: 80px; font-style: italic; }

/* --- Custom Music Player --- */
#audio-player { display: none; }
#custom-audio-controls {
    display: flex;
    align-items: center;
    gap: 10px;
}
#play-pause-btn {
    width: 40px;
    height: 40px;
    padding: 0;
    border-radius: 50%;
    display: flex;
    justify-content: center;
    align-items: center;
}
#progress-bar-container {
    flex-grow: 1;
    height: 8px;
    background-color: rgba(0,0,0,0.3);
    border-radius: 4px;
    cursor: pointer;
}
#progress-bar {
    width: 0;
    height: 100%;
    background-color: var(--highlight-color);
    border-radius: 4px;
}
#music-select {
    width: 100%;
    padding: 8px;
    background-color: transparent;
    color: var(--text-color);
    border: 1px solid var(--text-color);
    border-radius: 5px;
}
#music-select option {
    background-color: var(--bg-color);
    color: var(--text-color);
}


/* --- Finale Animation --- */
#controls-panel.celebration-mode * {
    animation-duration: 0.8s;
    animation-iteration-count: infinite;
    animation-timing-function: ease-in-out;
}
#controls-panel.celebration-mode button { animation-name: dance; }
#controls-panel.celebration-mode #current-time { animation-name: dance-scale; }
#controls-panel.celebration-mode #comment { animation-name: dance-color; }

@keyframes dance {
    0%, 100% { transform: rotate(-5deg) translateY(-5px); }
    50% { transform: rotate(5deg) translateY(5px); }
}
@keyframes dance-scale {
    0%, 100% { transform: scale(1); }
    50% { transform: scale(1.1); }
}
@keyframes dance-color {
    0%, 100% { color: var(--highlight-color); }
    50% { color: var(--accent-color); }
}

footer { 
    margin-top: auto; 
    font-size: 0.8em;
    opacity: 0.7;
}