var chapter_list = new Array(
  ["Vol.01 Ch.001: First Storm of Spring","v01/c001"],
  ["Vol.01 Ch.002: Last Storm of Spring","v01/c002"],
  ["Vol.01 Ch.003: Say That I Like It","v01/c003"],
  ["Vol.01 Ch.004: Cute Person","v01/c004"],
  ["Vol.02 Ch.005: Sleep","v02/c005"],
  ["Vol.02 Ch.006: Awakening","v02/c006"],
  ["Vol.02 Ch.007: Midsummer Cinderella","v02/c007"],
  ["Vol.02 Ch.008: Boy's Reason","v02/c008"],
  ["Vol.02 Ch.009: Season ~Moon Flower~ Prologue","v02/c009"],
  ["Vol.03 Ch.010: Season ~ Moonlight~ Postlude","v03/c010"],
  ["Vol.03 Ch.011: Gift","v03/c011"],
  ["Vol.03 Ch.012: Weakness","v03/c012"],
  ["Vol.03 Ch.013: Love and Secret","v03/c013"]
);

var total_chapters = 13;

for (var i = 0; i < chapter_list.length; i++) {
  document.getElementById('top_chapter_list').options[i] = new Option(chapter_list[i][0], chapter_list[i][1]);
  document.getElementById('bottom_chapter_list').options[i] = new Option(chapter_list[i][0], chapter_list[i][1]);
}
document.getElementById('top_chapter_list').value=current_chapter;
document.getElementById('bottom_chapter_list').value=current_chapter;
var current_chapter_index = document.getElementById('top_chapter_list').selectedIndex;